System for draining and analyzing body fluid and assessing health

Abstract

To provide a system for draining and analyzing body fluid and for assessing health conditions.SOLUTION: A system comprise: a drainage tube in fluid communication with an opening near a distal end of a catheter or at a distal end; a pump in fluid communication with the drainage tube and configured to apply a negative pressure to the drainage tube; a valve configured for a unidirectional flow and in fluid communication with the drainage tube; a pressure interface configured to be in fluid communication with the drainage tube; and a control part communicating with the pump. The control part is configured to actuate the pump to apply the negative pressure for clearing an airlock from the drainage tube, to monitor a quantity of urine from the patient over a predetermined period of time and to determine an intra-abdominal pressure on the basis of a measurement value received from a pressure interface, and may determine a risk of acute kidney injury on the basis of a change in a quantity of urine and a change in a pressure of the intra-abdominal pressure.SELECTED DRAWING: Figure 10A

Description

[Technical field]

[0001] The present invention relates to the field of medical devices, in particular to devices for assisting in bladder emptying, measuring urine volume and various urine parameters such as oxygen tension, urine conductance and urine specific gravity, monitoring renal function, analyzing urine parameters including urine volume, including the presence of infection, and tracking and / or controlling fluid administration.The present invention further relates to medical devices capable of sensing physiological data based on sensors integrated into catheters configured to be present in either the urinary tract, gastrointestinal tract, rectal location, preperitoneal, pleural space, or other body cavities. Incorporation by Reference

[0002] All publications and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference. [Background technology]

[0003] It is estimated that 10% of hospitalized and long-term care patients have an indwelling urinary catheter. Most critically ill patients receive one, and hourly monitoring of urine output is routine procedure in the ICU. The amount of urine produced is an indicator of fluid status and renal function. However, many sources of error can lead to erroneous measurement of this important indicator.

[0004] The most common device used for bladder drainage is the Foley catheter. The configuration of a flexible tube with a fixation balloon and small holes so that urine can drain through a central lumen has changed little since its introduction. However, it has been found that the current Foley catheter configuration can leave a large residual volume in the bladder, for example, more than 50 mL in a supine patient. See Non-Patent Document 1. In one study, the average residual volume was 96 mL in the ICU and 136 mL in a general ward. See Non-Patent Document 2. Large amounts of residual urine are also often found in the drainage tube connecting the Foley catheter to the drainage bag and elsewhere in the drainage system.

[0005] Residual urine in the bladder and drainage tube occurs because a large air bubble (airlock) forms in the tube, blocking the flow of urine from the bladder to the drainage bag. As a result, it is a routine procedure for nurses to manipulate the drainage tube before measuring the voided volume, which helps to empty the tube. In the ICU, where measurements are taken hourly, this becomes a very repetitive and inaccurate task. There is a need for more accurate automated urine volume measurements.

[0006] Additionally, within the urine collection system, there is an opportunity to measure and analyze urinary parameters.

[0007] In addition to improving urinary volume measurement and urinary parameter analysis, the drainage catheter itself offers untapped opportunities to sense, collect, and analyze additional patient parameters.

[0008] Also, many types of medical devices are configured to control the treatment and / or maintenance of a patient. For example, respirators, among others, can control the patient's breathing rate, volume, and / or gas mixture. IVs (intravenous delivery) can deliver fluids and / or other substances, such as drugs, to the patient. Other devices include those that can deliver medications or perform other actions. These types of medical devices can be tightly controlled with various settings, etc. A nurse or other practitioner can view various patient parameters and adjust the settings of the medical treatment device accordingly. There is a need for a control that automatically or semi-automatically uses the patient's parameters to control the settings of the medical treatment device. [Prior art documents] [Non-patent literature]

[0009] [Non-Patent Document 1] Fallis, Wendy M. Indwelling Foley Catheters Is the Current Design a Source of Erroneous Measurement of Urine Output? Critical Care Nurse 25.2 (2005): 44-51. [Non-Patent Document 2] Garcia et al., Traditional Foley Drainage Systems-Do They Drain the Bladder?, J Urol. 2007 Jan; 177(1):203-7; discussion 207. Summary of the Invention [Problem to be solved by the invention]

[0010] Foley-type catheters, being commonplace, low cost, and easily placed by medical personnel, can be used as a means to improve or add functionality to Foley-type catheters to derive important diagnostic information. The technology disclosed herein delivers highly resolved and previously unavailable diagnostic information, such as could be obtained from a Foley-type catheter with intraperitoneal pressure (and other) sensing capabilities.

[0011] In addition, the development of an airlock has been found to significantly distort intraperitoneal pressure measurements. In addition, a non-empty bladder can also adversely affect intravesical pressure measurements. The techniques disclosed herein also provide for the detection and elimination of airlocks in intraperitoneal pressure measurements or other settings, as well as more complete bladder drainage. [Means for solving the problem]

[0012] The technology disclosed herein seeks to more effectively drain the bladder, prevent and thereby eliminate airlocks in the drainage tube, and improve the accuracy of measuring urine volume in an automated manner. The disclosed technology also contemplates incorporating additional measurements of urine including oxygen tension, conductance, and specific gravity, gas pressure, turbidity, infection, sediment, etc., to improve monitoring of fluid status, renal function, and other important patient parameters.

[0013] The disclosed technology also relates to a Foley-type catheter for sensing physiological data from a patient's bladder and / or urinary tract, including, inter alia, data collected by high fidelity pressure sensing and conversion to a signal suitable for processing. In some embodiments, the pressure sensing Foley-type catheter may further enable sensing of temperature and clinically significant analytes. Examples of physiological parameters (temporal measurements and trends of values ​​over time) that a sensing Foley catheter system may measure include urine volume, respiratory rate, heart rate, heart rate variability, stroke volume, stroke volume variability, intra-abdominal pressure (IAP), tissue oxygenation, tissue gas volume, pulse transit time, pulmonary blood volume variability, body temperature, blood volume, and other patient parameters.

[0014] A drainage assembly configured to prevent negative pressure buildup according to one embodiment may generally include an elongate catheter having a first end configured for insertion into a body cavity. The catheter may have at least one opening near or at the first end in fluid communication with a catheter lumen formed therein, a drainage lumen in fluid communication with a second end of the catheter, a reservoir in fluid communication with the drainage lumen, and a venting mechanism in fluid communication with the drainage lumen and the positive pressure lumen. A valve may be disposed within the venting mechanism and configured to maintain a closed position until a first pressure level within the drainage lumen falls to a second pressure level such that the valve moves to an open position. A vent may also be disposed in fluid communication with the valve, the venting mechanism configured to inhibit wetting of the vent from fluid within the drainage lumen; and a controller in communication with the reservoir configured to determine an amount of fluid collected within the reservoir.

[0015] In another embodiment, the drainage assembly may be configured to prevent the buildup of negative pressure and generally includes an elongate catheter having a first end configured for insertion into a body cavity, the catheter having at least one opening near or at the first end in fluid communication with a catheter lumen formed therein. The drainage lumen may be in fluid communication with a second end of the catheter and may include a positive pressure lumen in fluid communication with the drainage lumen, a reservoir in fluid communication with the drainage lumen, and a venting mechanism coupled to the drainage lumen, the venting mechanism configured to inhibit venting from fluid in the drainage lumen. The controller may be in communication with the reservoir, the controller configured to determine the amount of fluid collected in the reservoir, and may further include a valve configurable between a closed position and an open position, the valve configured to move from the closed position to the open position when a first pressure level applied to the valve drops to a second pressure level.

[0016] Certain patient parameters that may be measured and / or determined by the disclosed technology are influenced by and / or impact the treatment of a patient with a medical treatment device. For example, a patient's urine volume, respiratory rate, heart rate, stroke volume, stroke volume variability, intra-abdominal pressure (IAP), tissue oxygenation, tissue gas volume, body temperature, blood volume, and other patient parameters are influenced by and / or impact the medical treatment. Examples of medical treatments that may be controlled by a medical device include respiratory rate and content controlled by a respirator, IV rate and content controlled by an IV drip controller, drug delivery controlled by a drug delivery device or IV controller, urine volume controlled by a urine volume pump, ascites volume controlled by a drain pump, and other treatments controlled by other medical treatment devices.

[0017] A system for analyzing bodily fluids according to one embodiment generally includes an elongate catheter having an expandable balloon disposed near or at a distal end of the catheter and further defining one or more openings proximate the balloon, a venting mechanism coupled to a proximal end of the catheter, the venting mechanism configured to allow air to pass therethrough when a negative pressure is applied to the venting mechanism, a first lumen coupled to the venting mechanism and in fluid communication with the one or more openings, a second lumen in fluid communication with the balloon, a reservoir coupled to a proximal end of the first lumen and in fluid communication with the one or more openings, and a controller configured to connect to the reservoir and programmed to control pressure in the first lumen, the controller further programmed to monitor urine output received from a patient into the reservoir and determine an intraperitoneal pressure of the patient based in part on changes in pressure in the balloon, and the controller further configured to store patient data.

[0018] In one exemplary method for analyzing one or more body parameters from a patient, the method generally includes placing an elongate catheter having an expandable balloon disposed near or at a distal end of the catheter within a body cavity at least partially filled with bodily fluid, receiving urine through one or more openings defined along the catheter proximate to the balloon, further receiving bodily fluid into a reservoir disposed outside the body cavity and in fluid communication with the one or more openings via a fluid lumen, evacuating air via a venting mechanism in communication with the fluid lumen when a negative pressure is applied to the fluid lumen, analyzing the amount of urine received in the reservoir via a controller programmed to control the negative pressure to the venting mechanism, determining an intra-abdominal pressure of the patient based in part on the change in pressure in the balloon, and storing one or more parameters of patient data via the controller.

[0019] Some embodiments of the sensing Foley catheter system include a loop controller that receives one or more pieces of data related to patient parameters and uses this information to control one or more medical treatment devices. The loop controller may be integral with either the device that measures the patient parameters, or the medical treatment devices, or both.

[0020] A pressure measuring balloon on a catheter, such as that disclosed in International Patent Application No. PCT / US14 / 44565 entitled Sensing Foley Catheter, is one example of a device for measuring patient parameters (herein incorporated by reference in its entirety). Additional embodiments are disclosed herein. The sensing Foley catheter system includes a pressure measuring balloon and / or other sensors, and may further have the capability to measure urine volume and contents to determine patient parameters such as urine output rate, IAP, respiratory rate, heart rate, stroke volume, tissue oxygenation, urine composition, temperature, and other patient parameters.

[0021] Other parameters that may be measured and / or determined via a sensing Foley-type catheter include urine specific gravity and pulse pressure variation, which may be used to assist in the control of medical treatment devices such as ventilators and / or fluid and / or hydration devices.

[0022] Urine specific gravity is a measure of the number and weight of solute particles in urine. A typical range is around 1.010 to 1.030. A higher reading may indicate dehydration or other conditions. A lower reading may indicate fluid overload or other conditions. Measurements may be taken by multiple sensors on a sensing Foley catheter. Measurements may indicate that the patient needs more fluid (in the case of dehydration) or less (in the case of fluid overload). Measurements may also indicate changes in ventilation parameters, infusion of medication, etc.

[0023] Pulse pressure variation can be a predictor of fluid responsiveness for medical treatment devices such as ventilators and / or fluid infusion devices. A sensing Foley catheter can record the pressure waveform and the controller can identify maximum and minimum pressure pulses that coincide with the respiratory cycle. The controller can calculate the variability in pulse pressure. Pulse pressure variation helps determine whether a particular patient will respond to fluid therapy. Pulse pressure variation can also be used by the controller to control therapy in a feedback loop. If the pulse pressure variation is high, the patient may need more fluid. If the pulse pressure variation is low, less fluid may be needed.

[0024] A sensing Foley catheter system can measure cardiac activity via pressure sensing in the bladder. A sensing Foley catheter can measure respiratory activity as well as cardiac activity, and the patient's respiratory and heart rates may have similar frequencies, so that the patient's respiratory measurements may distort the cardiac measurements. To overcome this problem, some embodiments of the controller may pause the respirator at the end of one or more inspiration points and / or pause the respirator at the end of one or more expiration points (for only a few seconds each time, e.g., 1-3 seconds, or e.g., 1-4 seconds) so that the cardiac waveform can be captured without respiratory distortion. Capturing detailed cardiac waveforms in this manner allows the controller to determine stroke volume variation (SVV), which is useful for detecting sepsis and preventing fluid overload. In an alternative embodiment, the patient may be asked to hold their breath at the inspiration and / or expiration points.

[0025] In another embodiment, a catheter system may generally include a catheter having at least one opening near or at a distal end of the catheter, a barb in fluid communication with a proximal end of the catheter, a drainage tube in fluid communication with the at least one opening, and a vent tube in fluid communication with the barb. A one-way valve may be disposed in-line with the vent tube at a location proximal to the barb, and a controller may be in communication with the one-way valve, the controller being programmed to apply a negative pressure to the drainage tube, which opens the one-way valve to allow fluid to pass through the vent tube.

[0026] In another embodiment, a method for draining fluid may generally include placing a catheter system adjacent to a subject's body, the catheter system having a catheter with at least one opening near or at a distal end of the catheter, a barb in fluid communication with a proximal end of the catheter, and a drainage tube in fluid communication with the at least one opening. A control in communication with the one-way valve may be activated with the one-way valve disposed in-line with the vent tube and in fluid communication with the barb, the one-way valve further disposed at a location proximal to the barb. Negative pressure is applied to the drainage tube, which opens the one-way valve and allows fluid to pass through the vent tube.

[0027] In another embodiment, a system for assessing a patient's health status may generally include a drainage tube configured to be in fluid communication with at least one opening disposed near or at a distal end of a catheter, a pump in fluid communication with the drainage tube and configured to apply negative pressure to the drainage tube, and a valve configured for unidirectional flow and in fluid communication with the drainage tube. A controller may be in communication with the pump, the controller configured to operate the pump to apply negative pressure to clear the airlock from the drainage tube. The controller may be configured to monitor urine volume from the patient for a first predetermined period above the urine volume threshold and for a second predetermined period below the urine volume threshold, and the controller may be further configured to determine a risk of acute kidney injury (AKI) when the urine volume below the urine volume threshold exceeds the second predetermined period.

[0028] In another embodiment, a method for assessing a patient's health generally includes receiving a urinary output from a patient via a catheter having at least one opening at a proximal or distal end of the catheter, applying a negative pressure to a drainage tube in fluid communication with the at least one opening until an airlock is cleared from the drainage tube, monitoring the urinary output via a controller for a first predetermined period of time above a urinary output threshold, and further monitoring the urinary output for a second predetermined period of time below the urinary output threshold. Additionally, the method may include determining a risk of AKI when the urinary volume below the urinary volume threshold exceeds a second predetermined period of time. [Brief description of the drawings]

[0029] [Figure 1] FIG. 1 illustrates a sensing Foley-type catheter according to one embodiment. [Diagram 2] FIG. 2 is a diagram showing an example of respiratory rate detection data. [Diagram 3] FIG. 3 shows a detailed view of the respiratory profile. [Figure 4] FIG. 4 is a diagram showing an example of detected data of heart rate and relative cardiac output. [Diagram 5] FIG. 5 illustrates data related to relative cardiac output sensing during leg raising exercise in humans. [Figure 6] FIG. 6 is a diagram showing an example of peritoneum detection data. [Figure 7] FIG. 7 is a diagram showing an example of peritoneum detection data. [Figure 8] FIG. 8 is a diagram showing the relationship between intraperitoneal pressure, respiratory wave pressure, and cardiac pressure. [Figure 9] FIG. 9 is a flow diagram of one embodiment of the method of the present invention. [Figure 10A] FIG. 10A illustrates a sensing Foley catheter according to one embodiment. [Figure 10B] FIG. 10B is a detailed view showing the airlock relief mechanism and fluid collection and analysis system of FIG. 10A. [Figure 10C] FIG. 10C illustrates disposable components of a sensing Foley catheter system according to one embodiment. [Figure 11A] FIG. 11A illustrates various embodiments of a sensing Foley catheter system. [Figure 11B] FIG. 11B illustrates various embodiments of a sensing Foley catheter system. [Figure 11C] FIG. 11C illustrates various embodiments of a sensing Foley catheter system. [Figure 11D] FIG. 11D illustrates a vent tube according to one embodiment. [Figure 11E] FIG. 11E illustrates a catheter system in which the vent lumen is in direct fluid communication with a fluid collection bag according to one embodiment. [Figure 11F] FIG. 11F is a graphical representation of the valve opening cycle. [Figure 12A] FIG. 12A illustrates an alternative sensing Foley catheter system. [Figure 12B]FIG. 12B illustrates an alternative sensing Foley catheter system. [Figure 13] FIG. 13 illustrates an alternative sensing Foley catheter. [Figure 14A] FIG. 14A illustrates a collapsible drainage tube within a kink-resistant tube according to one embodiment of the present invention. [Figure 14B] FIG. 14B illustrates a collapsible drainage tube within a kink-resistant tube according to one embodiment of the present invention. [Figure 15] FIG. 15 illustrates an example of a elimination mechanism for a sensing Foley catheter system. [Figure 16] FIG. 16 illustrates an example of a elimination mechanism for a sensing Foley catheter system. [Figure 17] FIG. 17 illustrates a sensing Foley catheter system with a drainage tube having a gas sampling lumen according to one embodiment. [Figure 18] FIG. 18 illustrates an active vent system including a vent and a pump. [Figure 19] FIG. 19 illustrates a sensing Foley catheter system further comprising a vent for pressure relief and sterilization according to one embodiment. [Figure 20] FIG. 20 illustrates a sensing Foley catheter system with a pressure relief vent and a pressure relief valve according to one embodiment. [Figure 21] FIG. 21 illustrates a urine collection container, urine collection chamber, or urine collection cassette that may be included in a sensing Foley catheter system to detect bacteria, blood, and / or other substances in urine using UV / light spectroscopy, according to one embodiment. [Figure 22A] FIG. 22A is a diagram showing various absorption wavelengths of light for E. coli, red blood cells, and plasma in urine. [Figure 22B] FIG. 22B illustrates a display according to one embodiment. [Figure 23]FIG. 23 illustrates a cassette including baffles or flaps according to one embodiment. [Figure 24] FIG. 24 is a graph depicting a method for priming a pressure balloon in accordance with some embodiments. [Diagram 25] FIG. 25 is a graph depicting a method for priming a pressure balloon in accordance with some embodiments. [Figure 26] FIG. 26 is a flow chart of possible logic in various embodiments of the present invention. [Figure 27] FIG. 27 is a flow chart of possible logic in various embodiments of the present invention. [Figure 28] FIG. 28 illustrates a flow chart of possible logic in various embodiments of the present invention. [Figure 29] FIG. 29 illustrates a sensing Foley catheter system with loop control in a patient environment according to one embodiment. [Diagram 30] FIG. 30 illustrates a sensing Foley catheter system with loop control in a patient environment according to one embodiment. [Diagram 31] FIG. 31 illustrates a sensing Foley catheter system with loop control in a patient environment according to one embodiment. [Diagram 32] FIG. 32 illustrates a sensing Foley catheter system with loop control in a patient environment according to one embodiment. [Diagram 33] FIG. 33 shows details of a loop control section with possible input parameters and output actions. [Diagram 34] FIG. 34 is a plot of ultrasonic and pressure measurements of volumetric divergence. [Diagram 35] FIG. 35 illustrates a distal end of a sensing Foley catheter according to one embodiment. [Diagram 36] FIG. 36 illustrates a filter in a balloon according to one embodiment. [Figure 37]FIG. 37 illustrates a filter within a balloon with the balloon inflated according to one embodiment. [Figure 38] FIG. 38 illustrates a filter within a balloon with the balloon deflated according to one embodiment. [Figure 39] FIG. 39 illustrates a filter within a balloon according to one embodiment. [Diagram 40] FIG. 40 illustrates a filter within a balloon according to one embodiment. [Diagram 41] FIG. 41 illustrates a filter within a balloon according to one embodiment. [Diagram 42] FIG. 42 illustrates a filter in a balloon according to one embodiment. [Diagram 43] FIG. 43 illustrates a filter within a balloon according to one embodiment. [Diagram 44] FIG. 44 illustrates a filter in a balloon according to one embodiment. [Diagram 45] FIG. 45 illustrates a filter in a balloon according to one embodiment. [Diagram 46] FIG. 46 illustrates a filter in a balloon according to one embodiment. [Figure 47] FIG. 47 illustrates a balloon having multiple access lumens according to one embodiment. [Figure 48] FIG. 48 illustrates an embodiment of a balloon. [Figure 49] FIG. 49 illustrates an embodiment of a balloon. [Figure 50] FIG. 50 illustrates various embodiments of balloon catheters having gas permeable membranes. [Figure 51] FIG. 51 illustrates various embodiments of balloon catheters having gas permeable membranes. [Figure 52] FIG. 52 illustrates various embodiments of balloon catheters having gas permeable membranes. [Figure 53] FIG. 53 illustrates various embodiments of balloon catheters having gas permeable membranes. [Figure 54] FIG. 54 shows a control unit for measuring the amount of gas via a balloon catheter. [Figure 55] FIG. 55 is a schematic diagram showing a gas measuring catheter / control unit system. [Figure 56] FIG. 56 is a schematic diagram showing a gas measuring catheter / control unit system. [Figure 57A] FIG. 57A shows an embodiment of a gas measurement attachment. [Figure 57B] FIG. 57B shows an embodiment of a gas measurement attachment. [Figure 58A] FIG. 58A is a table listing parameter combinations that allow possible signatures for identifying acute renal failure and UTI based on patient parameters. [Figure 58B] FIG. 58B is a table listing parameter combinations that allow possible signatures for distinguishing between acute kidney injury, sepsis, and acute respiratory distress syndrome based on patient parameters. [Figure 59] FIG. 59 shows the pressure signature curve within the urine collection chamber during clearance of the airlock. [Figure 60] FIG. 60 is a block diagram illustrating a data processing system that may be used in any embodiment of the present invention. [Figure 61] FIG. 61 illustrates alternative wavelengths that can be used to distinguish red blood cells and / or plasma / white blood cells. [Figure 62] FIG. 62 shows urine volume data immediately after administration of a diuretic. [Figure 63A] FIG. 63A illustrates that the smaller diameter lumen can be compared to the larger diameter lumen of the vent / filter region. [Figure 63B] FIG. 63A shows the small diameter lumen, while FIG. 63B shows the larger lumen of the vent / filter area. [Figure 64] FIG. 64 shows a curved barb region. [Figure 65]FIG. 65 illustrates a sensing Foley catheter system with a vent tube according to one embodiment. [Figure 66] FIG. 66 illustrates a sensing Foley catheter system with separate positive pressure vent tubes. [Figure 67] FIG. 67 is an enlarged view of the barb region of FIG. [Figure 68] FIG. 68 illustrates the barb regions of various embodiments of a sensing Foley catheter system. [Figure 69] FIG. 69 illustrates the barb regions of various embodiments of a sensing Foley catheter system. [Figure 70] FIG. 70 illustrates the barb regions of various embodiments of a sensing Foley catheter system. [Figure 71] FIG. 71 illustrates the barb regions of various embodiments of a sensing Foley catheter system. [Figure 72] FIG. 72 illustrates the barb regions of various embodiments of a sensing Foley catheter system. [Figure 73A] FIG. 73A illustrates the barb regions of various embodiments of a sensing Foley catheter system. [Figure 73B] FIG. 73B illustrates the barb regions of various embodiments of the sensing Foley catheter system. [Figure 74] FIG. 74 illustrates the barb regions of various embodiments of a sensing Foley catheter system. [Fig. 75A] FIG. 75A illustrates the barb regions of various embodiments of a sensing Foley catheter system. [Fig. 75B] FIG. 75B illustrates the barb regions of various embodiments of the sensing Foley catheter system. [Figure 76] FIG. 76 illustrates the barb regions of various embodiments of a sensing Foley catheter system. [Figure 77A]FIG. 77A illustrates the barb regions of various embodiments of a sensing Foley catheter system. [Fig. 77B] FIG. 77B illustrates the barb regions of various embodiments of a sensing Foley catheter system. [Figure 78] FIG. 78 illustrates the barb regions of various embodiments of a sensing Foley catheter system. [Figure 79] FIG. 79 illustrates the barb regions of various embodiments of a sensing Foley catheter system. [Figure 80A] FIG. 80A illustrates the barb regions of various embodiments of a sensing Foley catheter system. [Figure 80B] FIG. 80B illustrates the barb regions of various embodiments of a sensing Foley catheter system. [Figure 81] FIG. 81 illustrates the barb regions of various embodiments of a sensing Foley catheter system. [Fig. 82A] FIG. 82A illustrates the barb regions of various embodiments of a sensing Foley catheter system. [Fig. 82B] FIG. 82B illustrates the barb regions of various embodiments of a sensing Foley catheter system. [Figure 83] FIG. 83 illustrates the barb regions of various embodiments of a sensing Foley catheter system. [Figure 84] FIG. 84 illustrates the barb regions of various embodiments of a sensing Foley catheter system. [Figure 85] FIG. 85 illustrates the barb regions of various embodiments of a sensing Foley catheter system. [Figure 86] FIG. 86 illustrates the barb regions of various embodiments of a sensing Foley catheter system. [Figure 87] FIG. 87 illustrates a sensing Foley catheter system with an internal vent tube according to one embodiment. [Figure 88]FIG. 88 illustrates a sensing Foley catheter system with an internal vent tube according to one embodiment. [Figure 89] FIG. 89 illustrates a sensing Foley catheter system with an internal vent tube and a positive pressure tube according to one embodiment. [Figure 90] FIG. 90 illustrates a sensing Foley catheter system with an internal vent tube according to one embodiment. [Figure 91A] FIG. 91A illustrates a sensing Foley catheter system with an internal vent tube according to one embodiment. [Figure 91B] FIG. 91B illustrates a sensing Foley catheter system with an internal vent tube according to one embodiment. [Fig. 91C] FIG. 91C illustrates a sensing Foley catheter system with concentric vent and drainage lumens. [Fig. 91D] FIG. 91D illustrates a sensing Foley catheter system with concentric vent and drainage lumens. [Figure 92A] FIG. 92A illustrates several embodiments of the drainage lumen. [Fig. 92B] FIG. 92B illustrates several embodiments of the drainage lumen. [Figure 93A] FIG. 93A shows an alternative example of a drainage lumen. [Figure 93B] FIG. 93B shows an alternative drainage lumen. [Figure 93C] FIG. 93C shows an alternative drainage lumen. [Figure 93D] FIG. 93D shows an alternative drainage lumen. [Figure 93E] FIG. 93E shows an alternative example of a drainage lumen. [Figure 94A] FIG. 94A illustrates an embodiment of a sensing Foley catheter system in which the pressure sensors are on a separate catheter. [Figure 94B] FIG. 94B illustrates an embodiment of a sensing Foley catheter system in which the pressure sensors are on a separate catheter. [Fig. 94C] FIG. 94C illustrates an embodiment of a sensing Foley catheter system in which the pressure sensors are on a separate catheter. [Figure 95A] FIG. 95A illustrates an embodiment of a sensing Foley catheter system with a bubble reduction mechanism. [Figure 95B] FIG. 95B illustrates an embodiment of a sensing Foley catheter system with a bubble reduction mechanism. [Figure 95C] FIG. 95C illustrates an embodiment of a sensing Foley catheter system with an air bubble reduction mechanism. [Figure 96A] FIG. 96A illustrates an embodiment of a sensing Foley catheter system with a bubble reduction mechanism. [Figure 96B] FIG. 96B illustrates an embodiment of a sensing Foley catheter system with an air bubble reduction mechanism. [Figure 96C] FIG. 96C illustrates an embodiment of a sensing Foley catheter system with an air bubble reduction mechanism. [Figure 96D] FIG. 96D illustrates an embodiment of a sensing Foley catheter system with an air bubble reduction mechanism. [Figure 97A] FIG. 97A illustrates an embodiment of a sensing Foley catheter system with a bubble reduction mechanism. [Figure 97B] FIG. 97B illustrates an embodiment of a sensing Foley catheter system with an air bubble reduction mechanism. [Figure 97C] FIG. 97C illustrates an embodiment of a sensing Foley catheter system with an air bubble reduction mechanism. [Fig. 97D] FIG. 97D illustrates an embodiment of a sensing Foley catheter system with an air bubble reduction mechanism. [Figure 98A] FIG. 98A illustrates an embodiment of a sensing Foley catheter system with a bubble reduction mechanism. [Figure 98B] FIG. 98B illustrates an embodiment of a sensing Foley catheter system with a bubble reduction mechanism. [Figure 98C] FIG. 98C illustrates an embodiment of a sensing Foley catheter system with an air bubble reduction mechanism. [Figure 98D] FIG. 98D illustrates an embodiment of a sensing Foley catheter system with an air bubble reduction mechanism. [Figure 99A] FIG. 99A illustrates an embodiment of a sensing Foley catheter system with a bubble reduction mechanism. [Figure 99BC] FIG. 99BC illustrates an embodiment of a sensing Foley catheter system with an air bubble reduction mechanism. [Figure 100A] FIG. 100A illustrates an embodiment of a sensing Foley catheter system with a bubble reduction mechanism. [Figure 100B] FIG. 100B illustrates an embodiment of a sensing Foley catheter system with a bubble reduction mechanism. [Figure 100C] FIG. 100C illustrates an embodiment of a sensing Foley catheter system with an air bubble reduction mechanism. [Figure 101A] FIG. 101A illustrates an embodiment of a sensing Foley catheter system with a bubble reduction mechanism. [Figure 101B] FIG. 101B illustrates an embodiment of a sensing Foley catheter system with a bubble reduction mechanism. [Figure 101C] FIG. 101C illustrates an embodiment of a sensing Foley catheter system with complex flow paths within a urine collection reservoir. [Figure 101D] FIG. 101D illustrates an embodiment of a sensing Foley catheter system with complex flow paths within a urine collection reservoir. [Figure 101E] FIG. 101E illustrates an embodiment of a sensing Foley catheter system with complex flow paths within a urine collection reservoir. [Figure 102]FIG. 102 shows a pressure waveform and its disappearance using a pressure balloon. [Figure 103] FIG. 103 shows sample clinical data illustrating how an electrocardiogram can be used to remove noise from a cardiac signal. [Figure 104] FIG. 104 shows sample clinical data to illustrate stroke volume variability analysis using model waveforms. [Figure 105A] FIG. 105A illustrates cassette-side components of the sealing mechanism for several lumens between the cassette and controller / monitor in accordance with one embodiment. [Figure 105B] FIG. 105B illustrates cassette-side components of the sealing mechanism for several lumens between the cassette and controller / monitor in accordance with one embodiment. [Fig. 106] FIG. 106 illustrates components of the control side of the embodiment of the sealing mechanism shown in FIGS. 105A and 105B. [Figure 107A] FIG. 107A illustrates an embodiment of a lumen connection sealing mechanism between the cassette and the control unit. [Figure 107B] FIG. 107B illustrates an embodiment of a lumen connection sealing mechanism between the cassette and the control unit. [Figure 108] FIG. 108 illustrates an embodiment of a lumen connection sealing mechanism on the rear surface of the cassette. [Fig. 109] FIG. 109 is a cross-sectional view showing the lumen connection sealing mechanism on the rear surface of the cassette. [Figure 110] FIG. 110 is a dimensional diagram showing cassette-side components of a sealing mechanism for sealing some of the lumens between the cassette and the controller / monitor in accordance with one embodiment. [Figure 111] FIG. 111 is a force diagram showing cassette-side components of a sealing mechanism for sealing some lumens between the cassette and controller / monitor in accordance with one embodiment. [Figure 112]FIG. 112 illustrates an embodiment that includes a venting mechanism that can be added to any urinary drainage system that includes a sampling port. [Figure 113] FIG. 113 illustrates an embodiment including a pump / biasing member. [Fig. 114] FIG. 114 illustrates an embodiment in which the drainage tube includes a coiled or compressed section. [Fig. 115A] FIG. 115A illustrates a barb including a tube seating feature according to one embodiment. [Fig. 115B] FIG. 115B illustrates a barb including a tube seating feature according to one embodiment. [Fig. 116A] FIG. 116A shows an example of a possible method for predicting risk of kidney damage earlier than the RIFLE criteria. [Fig. 116B] FIG. 116B shows an example of a possible method for predicting risk of kidney damage earlier than the RIFLE criteria. [Figure 116C] FIG. 116C shows an example of a possible method for predicting risk of kidney damage earlier than the RIFLE criteria. [Fig. 116D] FIG. 116D shows an example of a possible method for predicting risk of kidney damage earlier than the RIFLE criteria. [Figure 116E] FIG. 116E shows an example of a possible method for predicting risk of kidney damage earlier than the RIFLE criteria. [Fig. 117A] FIG. 117A illustrates a sensing Foley system including a peristaltic pump according to one embodiment. [Fig. 117B] FIG. 117B illustrates a sensing Foley system including a peristaltic pump according to one embodiment. [Fig. 117C] FIG. 117C illustrates a sensing Foley system including a peristaltic pump according to one embodiment. [Fig. 118A] FIG. 118A illustrates an example screenshot of an embodiment disclosed herein. [Fig. 118B]FIG. 118B is a diagram illustrating an example screenshot of an embodiment disclosed herein. [Fig. 118C] FIG. 118C illustrates an exemplary screenshot of an embodiment disclosed herein. [Fig. 119A] FIG. 119A illustrates a sensing Foley catheter system including analysis and recording of various urinary parameters according to one embodiment. [Fig. 119B] FIG. 119B illustrates a sensing Foley catheter system including analysis and recording of various urinary parameters according to one embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0030] A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention are utilized, and the accompanying drawings of which:

[0031] Preferred embodiments of the invention are described in detail herein. However, alternative embodiments of the various elements of the device are possible. Examples of these embodiments are provided below, but the scope of the invention is not limited to these particular configurations.

[0032] Sensing Foley Catheter

[0033] 1 is a diagram illustrating a sensing Foley catheter and some of its elements according to one embodiment. The catheter may be understood to have various portions depending on its location when inserted into a human subject, such as a proximal portion that remains outside the subject, a central or urethral portion that remains, and a distal or urethrovesical portion that remains.

[0034] Various internal lumens traverse the length of the catheter 102, such as air or fluid lumens that communicate with the bladder retention balloon 104 and retention balloon port 118. The urinary drainage lumen has one or more distal openings 106 in the bladder portion of the catheter and an opening at the proximal end 114 of the catheter. The urinary drainage lumen may also be connected to a urinary drainage tube that conveys urine to a urine collection container. The urinary drainage tube may be separate from the sensing Foley catheter or may be integral with the sensing Foley catheter. In some embodiments, the drainage tube lumen and distal opening in the bladder also serve as an infusion conduit through which medicinal agents may be infused or heated or cooled fluids may be infused. One or more analyte sensors (not shown) or one or more temperature sensors (not shown) may be located on the catheter, either in the urethral or bladder-dwelling portion of the catheter. Electrical or optical fiber leads may be positioned within the lumen to allow communication of sensing signals between a distally positioned sensor and a proximal portion of the catheter for subsequent further communication to a data processing device or controller.

[0035] An inflatable pressure sensing balloon 108 (or a pressure sensing membrane disposed across the opening) may be disposed at or near the distal end of the catheter. Pressure sensing balloon or pressure sensing membrane embodiments may be understood as constituting a pressure interface having a distal facing surface exposed to pressure from within the bladder and a proximal facing surface exposed to the proximal fluid column. The pressure sensing balloon or membrane is in fluid communication with a fluid column or lumen that is in fluid communication with a pressure port 116 at or near the proximal end of the catheter. Fluid column (filled with a fluid, either liquid or gas) embodiments may constitute a dedicated lumen or a shared lumen.

[0036] In some embodiments, the temperature sensor may be at or near the distal end of the catheter. The temperature port 110 may include a temperature communication wire 112 that connects the temperature sensor to a display, connector and / or controller.

[0037] 1 shows the proximal end of the catheter consisting of multiple individual ports, it is noted that some or all of the ports may be integrated into a single port or, alternatively, may be integrated into a urinary drainage line that runs to a urinary drainage system and / or control. Other lumens and / or ports may also be present.

[0038] Pressure-based physiological parameters that the sensing Foley catheter system may sense and / or determine via the controller based on the sensed parameters may illustratively include peritoneal pressure, respiratory rate, and heart rate, relative pulmonary tidal volume profile, cardiac output, relative cardiac output, and absolute stroke volume. Some embodiments of the Foley catheter may further comprise any of a temperature sensor, one or more analyte sensors, electrodes, and paired light sources and sensors. As described above, further comprising embodiments may provide other forms of physiological data, such as, for example, blood pressure, oxygen saturation, pulse oximetry, EKG, and capillary filling pressure.

[0039] Embodiments of a sensing Foley catheter may sense any one or more of a number of clinically relevant parameters, including but not limited to the following examples: urine pH, urine oxygen content, urine nitrate content, respiratory rate, heart rate, bladder or urethral wall perfusion pressure, temperature within the bladder or urethra, electrocardiogram via a sensor on the bladder wall or urethra, respiratory volume, respiratory pressure, peritoneal pressure, urine glucose, blood glucose via the urethral and / or bladder mucosa, urine protein, urine hemoglobin, blood pressure. While in some embodiments the catheter may sense multiple parameters, in some embodiments it may be limited to only a single number of parameters for a focused application (e.g., respiratory rate in a patient in respiratory distress).

[0040] The disclosed technology captures high-resolution time series profiles (pressure as a function of time) of peritoneal pressure from within the bladder, which can be converted and processed into individual pressure profiles that can be assigned to specific physiological sources, including peritoneal pressure, respiratory rate, and heart rate. By tracking the pressure profiles with a sufficiently rapid sampling rate, as provided by the present technology, the pressure profiles can be further decomposed and / or analyzed into relative pulmonary tidal volume, cardiac output, relative cardiac output, and absolute stroke volume.

[0041] Thus, aspects of the disclosed technology relate to the fidelity and resolution of a pressure signal generated in response to changes in pressure within the bladder that reflect the pressure profile within the peritoneal cavity, which pressure profile includes cumulative input from the physiological sources described above. Aspects of the technology further relate to the fidelity and resolution of the transfer of the pressure signal to a highly resolved electrical signal. Aspects of the technology further relate to processing the entire electrical signal profile, which is a surrogate for the pressure profile within the peritoneal cavity, into component profiles that can be assigned to physiological sources.

[0042] The sensitivity of an inflated balloon as a pressure sensor is a function of the differential pressure across the balloon membrane as a baseline condition. The balloon is most sensitive to pressure when the baseline differential pressure is close to zero. As the baseline differential pressure increases, the sensitivity of the pressure sensing balloon decreases. Thus, the disclosed technology provides an automated priming method that minimizes differential pressure while maintaining the balloon inflated.

[0043] To effectively capture a physiological pressure profile, the profile must be sampled at a rate sufficient to resolve the inherent frequency of change in the profile. This consideration is based on the Nyquist-Shannon sampling theorem, which states that to resolve events that execute at a frequency of B cycles / sec, a sampling frequency of at least 2B samples / sec is required. As applied to physiological pressure cycles, for example, a heart rate of 70 beats / min requires a sampling rate of at least 140 samples / min to effectively capture the cycle. This relationship is the basis for aspects of the disclosed technology that define the sampling rates specifically required to capture physiological pressure cycles such as relative pulmonary tidal volume, cardiac output, relative cardiac output, and absolute stroke volume.

[0044] Embodiments of the present technology include pressure interfaces such as those represented by balloons with either compliant or non-compliant membranes.

[0045] Expandable pressure-sensing balloons may assume one or more of at least two basic forms, compliant or non-compliant, per embodiment of the technology. In compliant balloon types, commonly likened to conventional party balloons, the pressure-sensitive balloon is formed from or includes a compliant membrane. Thus, the surface area of ​​the membrane expands or contracts as a function of the inflation of the balloon. The compliant nature of the membrane determines the various characteristics of the balloon at various inflation levels of the balloon. When inflated, the balloon, if unconstrained, maintains a substantially constant or preferred shape as determined by the mandrel on which the balloon is formed. As the balloon expands from a minimum volume to a maximum volume, the membrane of the balloon maintains a predetermined level of tension. Within the compliant nature of the compliant membrane, an increase in pressure during inflation causes an expansion in volume. Although a balloon may generally be considered compliant in part in that its shape corresponds to spatial constraints that may be encountered during expansion or inflation, a balloon may have a preferred or inherent shape that inhibits the level of shape compliance or conformance that a non-compliant balloon would exhibit.

[0046] In a non-compliant balloon, the inflatable pressure-sensing balloon is formed from or includes a non-compliant or substantially non-compliant membrane. Thus, the membrane surface area does not expand or contract in response to the degree of inflation / pressurization of the balloon. A non-compliant pressure-sensing balloon is generally likened to a conventional Mylar® balloon. The membrane's non-compliance generally determines the different characteristics of the balloon at the various inflation levels of the balloon. As the balloon expands from its minimum volume to near its maximum volume, the membrane of the balloon becomes flexible and sagging occurs. Inflation of a non-compliant balloon occurs by smoothing the wrinkles and folds of the membrane outward. Contraction or compression of a non-compliant balloon generally occurs by wrinkles and folds directed inward. When a non-compliant balloon is fully inflated (or substantially inflated) without being in a restricted space, the balloon assumes a preferred or unique shape as determined by the shape of the membrane or fabric of the balloon. However, in the partially inflated state, the balloon is generally very pliable and conformable, generally assuming any shape dictated by the confined space.

[0047] An expandable pressure sensing balloon according to an embodiment of the present technology may also include features of both the two basic forms of compliance and non-compliance. In these embodiments, the membrane may include compliant and non-compliant regions. This hybrid type of balloon will generally behave in a manner that elicits behavioral aspects of both compliant and non-compliant balloons, as described above. Additionally, a compliant balloon may be formed with a membrane that is not of homogenous composition or thickness. In such embodiments, regions of different thickness or composition may have various degrees of compliance, thus affecting the behavior of these regions during inflation of the balloon. In still other embodiments, the compliance of the membrane may have a bias or polarity that tends to allow compliance in one or more directions and not allow compliance in one or more other directions.

[0048] An embodiment of the sensing Foley catheter includes a device that utilizes a very small pressure lumen for air transmission. Pressure readings using lumen inner diameters of 3 mm, 1 mm, and 0.5 mm are measured. Little degradation of the signal was observed when the air lumen diameter was reduced from 3 mm to 1 mm to 0.5 mm.

[0049] These data demonstrate the suitability of using embodiments of the pressure transmission system in small diameter pediatric catheters, down to sizes as small as 4F. In this embodiment, the tip of the catheter can likewise be made lower profile than the remainder of the catheter to allow for consistent diameter reduction with the addition of a pressure sensing balloon. Thus, the catheter of the present invention is uniquely suited for pediatric indications where there is a dire need for better and less invasive monitoring methods. In another embodiment, the retention balloon itself can be used as the pressure balloon to minimize the number of lumens required. In one embodiment, the retention balloon is used in its fully inflated state and is used only to track macro trends in IAP. In another embodiment, the retention balloon is only slightly inflated to increase the balloon sensitivity to small changes in pressure. In this embodiment, micro parameters such as heart rate, relative stroke volume, relative cardiac output, respiratory rate, and relative tidal volume can be measured more finely. Also, the smaller pressure lumen allows for larger catheter space to be available for other technologies, such as sensors.

[0050] In embodiments of the sensing Foley catheter in which a retention balloon is used as a pressure balloon, the pressure measured in the retention balloon is offset by the pressure required to just inflate the balloon large enough to function as a retention balloon. As a result, the inflation pressure, and the pressure due to the retention balloon being in contact with the inner surface of the bladder, must be subtracted from the pressure measurement. In this way, smaller pressure changes may be tracked similarly to those measured by a separate pressure balloon. The offset of the inflation pressure may be determined by measuring the pressure in the retention balloon when it is first inserted into the patient, by measuring the inflation pressure of the retention balloon outside the patient, or by other means. The retention balloon may be filled with a fluid, air, or any other suitable gas.

[0051] Embodiments of the disclosed technology may include those in which the pressure sensor is a mechanical pressure sensor, for example using fiber optics, strain gauge, magnetic, resonant, and / or other suitable technologies.

[0052] 2 illustrates an example of respiratory rate sensing data from a human subject provided by a sensing Foley catheter system according to one embodiment. During this test period, the subject performs the following respiratory sequence: (1) breath hold at end of expiration, (2) Valsalva, (3) hyperventilation, (4) Valsalva, (5) breath hold at end of expiration.

[0053] Figure 3 shows a detailed portion of a normal breathing period in a breathing profile similar to that of Figure 2. Note that the pressure curve clearly shows the peaks of breathing and therefore the breathing rate can be determined, and the peaks of the heart rate and therefore the heart rate can be determined.

[0054] 4 shows an example of heart rate and relative cardiac output sensing data from a human subject, as provided by a sensing Foley catheter system according to one embodiment, showing simultaneously and independently measured electrocardiogram tracings. The graph clearly shows that the peaks in heart rate are consistent with the heart rate as measured by the sensing Foley catheter.

[0055] FIG. 5 illustrates data relating to relative cardiac output sensing during human leg-raising exercise where cardiac output increases as indicated by an increase in cardiac pulse amplitude.

[0056] The data shown in Figures 6 and 7 were obtained from a study conducted with Yorkshire pigs under an IACUC-approved protocol. Figure 6 illustrates an example of peritoneal sensing data focused on respiratory rate from a pig, as provided by a sensing Foley catheter system according to an embodiment. Figure 7 illustrates an example of a pig study showing the ability of a sensing Foley catheter system according to an embodiment to detect intraperitoneal hypertension. In this study, the peritoneal cavity was accessed with a 5 mm tenami trocar. The trocar was then attached to a bag of 5 L of emulsified Ringer's solution via a peristaltic pump, and the solution was infused at a rate of approximately 1 L per minute. Fluid flow was discontinued once a pressure of approximately 20 mmHg was obtained, at which point there was no net fluid flow into or out of the cavity.

[0057] FIG. 8 shows a schematic arrangement of intra-abdominal pressure, respiratory pressure wave pressure and cardiac pressure as a two-dimensional plot of pressure (in mmHg on a logarithmic scale) versus frequency (Hz). It can be seen that there is an inverse correlation between pressure and frequency, and that the various physiological pressure-related parameters occupy different sectors when arranged in this way. The distinctness of both these pressure and / or frequency profiles allows the embodiment of the method as disclosed herein to decompose a single overall pressure profile over time into distinct sub-profiles according to their physiological origin. The intra-abdominal pressure measurements may be analyzed in a frequency range of about 0 Hz to about 0.5 Hz. The respiratory pressure measurements may be analyzed in a frequency range of about 0.25 Hz to about 0.75 Hz. The cardiac pressure measurements may be analyzed in a frequency range of about 0.75 Hz to about 3.0 Hz. The intra-abdominal pressure measurements may be analyzed in an amplitude range of about 5 mmHg to about 30 mmHg. Respiratory pressure measurements may be analyzed over an amplitude range of about 0.5 mmHg to about 5 mmHg. Cardiac pressure measurements may be analyzed over an amplitude range of about 0 mmHg to about 0.5 mmHg. The sampling frequency, i.e., the frequency at which the pressure measurements are taken, is preferably about twice the resolution frequency. For example, the sampling frequency may be about 0 Hz to about 1 Hz for intra-abdominal pressure measurements, about 0.5 Hz to about 1.5 Hz for respiratory pressure measurements, and about 1.5 Hz to about 6 Hz for cardiac pressure measurements.

[0058] 9 is a flow diagram of a method for monitoring pressure dynamically occurring in the peritoneal cavity as waves of varying frequency and amplitude sensed from within the bladder according to one embodiment. Via a pressure interface, a high fidelity pressure profile is generated and transmitted proximally through the fluid column. More proximally, a pressure transducer converts the high fidelity pressure waves into high fidelity electrical signals indicative of the frequency and amplitude of the pressure. The generated high fidelity electrical signals are processed by a controller to generate data subsets reflecting components in the overall pressure profile that are attributable to specific physiological sources such as peritoneal pressure, respiratory rate, heart rate, relative cardiac output, patient movement or activity, etc.

[0059] Detection Foley Catheter System

[0060] 10A illustrates an embodiment of an airlock elimination ring mechanism and a sensing Foley catheter used in conjunction with a fluid collection and analysis system, both of which benefit from eliminating or reducing airlocks in the urinary drainage line.

[0061] The sensing Foley catheter 1000 is similar to the sensing Foley catheter shown in FIG. 1. The sensing Foley catheter is shown in use in the bladder 1014. Note that some of the ports at the proximal end of the catheter shown in FIG. 1 are combined in the embodiment shown in FIG. 10A. Also shown here is a urinary drainage tube 1001. The urinary drainage tube may be combined with the sensing Foley catheter or may be a separate item. The urinary drainage tube 1001 and / or the sensing Foley catheter may include a vent barb (or barbs) 1016, or the vent barb may be a separate item. An airlock elimination mechanism and fluid collection and analysis system 1002 are also shown here in fluid communication with the urinary drainage tube 1001, which is in fluid communication with the sensing Foley catheter 1000. The airlock elimination mechanism and fluid collection and analysis system includes a base / control unit 1018, a fluid collection bag 1020, and a reservoir or cassette 1022. The combination of the sensing Foley catheter 1000, the urinary drainage tube 1001, and the airlock elimination mechanism and fluid collection and analysis system 1002 is also referred to herein as a sensing Foley catheter system. The sensing Foley catheter, urinary drainage line, and reservoir / cassette may be disposable and sold as a unit. This disposable assembly is shown in FIG. 10D, which includes the sensing Foley catheter 1000, the urinary drainage tube 1001 (including a vent barb), and the reservoir / cassette 1022.

[0062] The vent barb 1016 may include one or more vents 1006, similar to the urine sampling port 1004. In this embodiment, the vents 1006 are preferably formed from a gas permeable but liquid impermeable membrane, such as a hydrophobic membrane. One example of such an exemplary vent is a PTFE (polytetrafluoroethylene), ePTFE (expanded PTFE), or Versapor (registered trademark, manufactured by Pall Corporation, Port Washington, NY) membrane, although other materials may be used. The vents may allow air to enter the system when negative pressure is applied to the drainage tube, and may allow air to exit when an airlock occurs in the drainage tube creating positive pressure. Such a mechanism prevents suction trauma, for example, at the bladder wall. The vents 1006 may incorporate a one-way valve that prevents air from exiting the drainage line, or may incorporate a one-way valve that prevents air from entering the drainage line. In a preferred embodiment, a one-way valve is used to prevent air from exiting the drainage line, but allows air to enter the drainage line via the vent 1006. In this manner, the valve also prevents urine from contacting the vent 1006.

[0063] The urinary drainage tube 1001 may include multiple lumens including a pressure lumen 1010, a temperature lumen 1008, and a urine lumen 1012. The pressure lumen 1010 is in fluid communication with the pressure sensing balloon 108 as well as a pressure transducer interface 1026 of the control unit 1018. The temperature lumen 1008 also communicates with a temperature sensor (not shown) in the sensing Foley catheter and a temperature connector port 1024 in the control unit. The urine lumen 1012 is in fluid communication with one or more openings 1006 and a urine reservoir or cassette 1022.

[0064] The disposable measurement reservoir, urine collection container, chamber, or cassette component 1022 is configured to fit into the cassette mount, base, or control unit 1018 and interface with the components of the control unit. The control unit pump interface (back of the cassette pump interface 1148) connects to the pump 1134, which connects to the cassette pump interface 1148 on the disposable cassette member. The pump is configured to generate a vacuum inside the cassette member, which is then transferred to the urine drainage lumen of the drainage line. Preferably, the urine collection container / cassette is rigid so that it maintains a constant volume when the pump applies negative pressure. The level of negative pressure applied may be monitored by a pressure sensor. During airlock clearance, the pressure follows a sign curve as shown in FIG. 59. As suction is applied, the pressure decreases, eventually reaching an inflection point as the urine meniscus passes the lowest point of the drainage tube. At this point, less suction is required to continue to clear the airlock, so the pump power can be reduced to minimize the amount of suction transferred to the bladder after the airlock is fully cleared. In a large container without this pressure sensing capability, for example, a substantial negative pressure would be transferred to the bladder after the airlock is cleared and before the container equilibrates to atmosphere. The controller pressure interface (back of the cassette pressure interface 1150) connects to a pressure measurement device, such as a pressure transducer, and connects to the cassette pressure interface 1150. The pressure measurement device is configured to measure a volume of bodily fluid, such as urine, based on the pressure exerted on the pressure measurement device, which may be a pressure transducer. The ultrasonic transducer interface 1130 also provides a urine volume measurement. The ultrasonic measurement may be used in conjunction with a pressure measurement, or either one may be used to measure the amount of volume of bodily fluid, such as urine. The active pinch valve 1132 is configured to connect to the cassette outlet tube. The pinch valve is for controlling the emptying of the cassette container, and the pinch valve is controlled by the controller to release the urine / fluid when the urine volume reaches a predetermined volume in the cassette, as measured by pressure and / or ultrasonic measurements.The amount of urine in the cassette is measured, and when a certain amount is reached, the amount is put into the urine drainage bag 1020 via a pinch valve, and the urine in the cassette is emptied. For example, the cassette may be emptied when the amount of urine in the cassette reaches about 50 mL. Alternatively, the cassette may be emptied when the amount of urine in the cassette reaches about 40 mL. Alternatively, the cassette may be emptied when the amount of urine in the cassette reaches about 30 mL. Alternatively, the cassette may be emptied when the amount of urine in the cassette reaches about 20 mL. Alternatively, the cassette may be emptied when the amount of urine in the cassette reaches about 10 mL. In this manner, the amount of urine output can be accurately measured over time.

[0065] In some embodiments, a capacitive micromachined ultrasonic transducer (CMUT) may be used to measure the urine volume in the cassette. This allows for a cheaper ultrasonic transducer that can cover the entire bottom of the cassette and / or one or more sides of the cassette. This may eliminate problematic cassette tilt.

[0066] Emptying of the cassette may be increased or accelerated by pressurizing the cassette during the emptying process.

[0067] Alternatively, the controller may utilize a set time between emptying of the cassette and measure the amount of urine in the cassette immediately prior to emptying. Alternatively, the controller may empty the cassette upon an event such as an airlock release caused by activation of a pump. For example, the controller may periodically set an airlock release cycle, then measure the amount of urine in the cassette, and then empty the cassette.

[0068] For example, the controller may control the pinch valve to empty the reservoir / cassette when the urine volume reaches approximately 50 ml. Alternatively, the controller may control the pinch valve to empty the reservoir / cassette hourly after measuring the urine volume in the cassette. Alternatively, the controller may control the pinch valve to empty the reservoir / cassette during or after a urine drainage event, such as running a pump. Alternatively, the controller may control the pinch valve to empty the reservoir / cassette using a combination of these triggers.

[0069] Other technologies for measuring urine volume may be used in addition to or instead of pressure and / or ultrasound, including pressure-based, resistive, capacitive, ultrasonic, or optical based technologies. Two or more technologies may be used so that measurements can be compared to one another to improve the accuracy of the volume measurement. Two or more volume measurements made by one or more technologies may be used for redundancy, or for backup, or in conjunction with one another to obtain a more accurate urine volume measurement.

[0070] For example, the camera may be used to recognize the fluid / air interface to measure the fluid level in the reservoir. The known dimensions of the reservoir can then be used by the control to calculate the fluid volume. The camera may also be used to identify the fluid / air interface and the edges of the reservoir to measure the tilt of the system. The control may calculate the angle between them to measure the tilt of the system. If this angle is changing rapidly over time, the control may determine that the system is moving, such as when a patient is moving between rooms. The control may signal an alert when a particular condition is detected by the camera / control. For example, a high tilt alert, a motion alert, a detection alert (when blood, air bubbles, or other conditions are detected in the urine), etc. In situations where the urine reservoir / system is placed on a horizontal surface, the tilt may approach 90 degrees. In such a situation, the control may determine that the reservoir is placed on its side and may not be functionally emptying, or that there is an increased likelihood of urine backflow into the drainage tube. The controller may automatically shut down certain functional aspects of the system, such as clearing the drain line, emptying the reservoir, etc. The controller may automatically put the system into a "dam foley mode" in which the urine drainage flow path bypasses the cassette and drains directly into the bag. Additionally or alternatively, the controller may shut down certain valves, such as the valve between the reservoir and the drainage tube.

[0071] A number of bed hooks 1116 are for hooking the control to a bed or other device, etc., if desired. They can also be used to hook the control to a portable device for patient transport. A number of collection bag hooks / holes 1102 are for attaching a drainage bag in which the urine / fluids are ultimately collected after passing through the pinch valve. The collection bag hooks 1102 may be configured to take a strain measurement such that the weight of the fluid in the bag can be determined, providing another method for measuring the volume of the fluid in the bag. For example, a piezoelectric transducer may be used. Specific gravity measurements may also be used by the control to determine useful volume measurements based on weight and specific gravity.

[0072] The screen 1110 is for displaying information including current urine / fluid volume status, system status, etc. The screen 1110 may also be a touch screen and receives input including settings, screen display changes, menu changes, etc. The pressure port 1026 connects to the bladder pressure line 1010 which, if used, measures bladder pressure using a sensing Foley catheter. Alternatively, the pressure port may be located in the cassette mount under the cassette 1022 or elsewhere in the control / base. The temperature in port 1024 connects to a thermistor / temperature sensor which measures body temperature via the sensing Foley catheter via lumen 1008 or by other means. The temperature output port 1122 is for sending any temperature measurements to an external device and / or monitor. The adapter port 1124 is for adapting the control to other devices, such as in the case of an RFID adapter. This can be used to activate any additional / advanced features such as measuring IAP, respiratory rate, heart rate, cardiac output, or any other parameter measurable by a sensing Foley catheter. This allows additional parameters to be enabled and paid for by the hospital only if that information is desired. Activation of advanced features may also be controlled, for example, by the use of different disposable components. Alternatively, advanced features may be enabled by software upgrades purchased as part of the disposable or separately. Software upgrades may be delivered over the air, by USB dongle, by microSD card, by EPROM card, or by other suitable techniques. Data for each patient and / or aggregated patients may also be stored by the control unit. Patient data may be stored in memory, USB, microSD card, EPROM card, hard disk, etc. Patient data may be transferred wirelessly or via a wired connection to another storage device, such as a server on the Internet or an intranet. Patient data may be anonymized.Patient data, such as a patient ID, may be stored in the RFID adapter so that data specific to a particular patient is recognized by the control unit and associated with the disposables used by that patient. The RFID adapter may be located on a disposable of the system, such as cassette 1022, or other location where a disposable interfaces with a non-disposable. Additionally, all patient data collected may be stored in the RFID adapter, allowing different monitors to be used with the same patient without switching out the disposable portion of the system.

[0073] A power LED / indicator 1114 indicates whether the power is on or off. An error LED / indicator 1112 is an indicator if any errors have occurred within the system. Details of the error may be displayed on the screen 1110, but the indicator 1112 alerts the user that an error exists. The indicator may also incorporate a sound or other alert.

[0074] Port 1108 is for downloading, uploading, software upgrades, connecting to other devices, such as integration with an Electronic Medical Record (EMR) system. Port 1108 may be a USB port or other suitable port. SD® port 1106 is for data download. Power port 1104 is for connecting the control to a power source, such as a wall, to provide power to the control.

[0075] The urine / fluid drainage bag 1020 includes one-way valves 1136 connected to the overflow tube 1138 and outflow tube 1140 to prevent urine / fluid from exiting the drainage bag once collected. These valves also prevent air from entering the urine collection container 1022 so that when the pump 1134 is pulling a vacuum, the vacuum acts on the drainage tube but not the bag. In a preferred embodiment, a single valve is used for both the overflow tube and the outflow tube. The mounting hook / hole 1102 allows the drainage bag 1020 to be removably attached to the control unit 1018. The vent 1142 may be a hydrophobic or other vent that allows air or gas to exit the drainage bag but does not allow fluid to exit the drainage bag. This prevents excess air and potential pressure from building up in the bag, which allows for efficient filling of the drainage bag. The progressive markings 1144 indicate a somewhat crude measurement of the amount of fluid in the bag as fluid is collected. An outflow valve 1146 may be used to empty the bag of fluid / urine. Preferably, the valve is easily operable by one person. The collection bag hook 1102, if configured as a strain measuring element, may also force an alarm to sound when the bag reaches full capacity and needs to be emptied. An alarm may also sound if the bag is subjected to unnecessary excessive force, for example, when the bag is pulled while moving the patient or gets caught on an obstacle. Weight, or mass, may also be used to determine if the bag is full, for example, using a weigh scale. Alternatively or additionally, pressure measurements in the reservoir / cassette may be used to determine when the bag is full.

[0076] An overflow barrier 1137 is shown in the urine collection container / reservoir / cassette 1022. The overflow barrier is generally at a height above the level at which the controller empties the cassette. For example, if the controller empties the cassette when the fluid volume reaches 50 ml, the overflow barrier will reach a height above the 50 ml volume. For example, the overflow barrier may be about 5-10 mm above the empty volume. Alternatively, the overflow barrier may be about 10-20 mm above the empty volume. Alternatively, the overflow barrier may be about 20-30 mm above the empty volume. Alternatively, the overflow barrier may be about 30-40 mm above the empty volume. Alternatively, the overflow barrier may be about 40-50 mm above the empty volume. Alternatively, the overflow barrier may be about 50-100 mm above the empty volume. The path between the urine collection area 1135 and the overflow area 1139 may be direct, as shown here, or it may be more tortuous or complex, as shown in Figures 101B-101E.

[0077] The patient's temperature is measured using a thermistor / temperature sensor placed inside the patient's body. This temperature may be passed through a control unit for display on a third party device. Figure 10B shows that a parallel potentiometer may be used to reduce errors in the temperature measurement before the temperature measurement is transferred to an external display or device.

[0078] The drainage bag can be made of a suitable material such as clear vinyl. The one-way valve can be made of a suitable material such as vinyl. The hydrophobic vent can be made of ePTFE, Versapor®, or other suitable material. The outflow valve can be made of PVC, PC, or other suitable material.

[0079] Pressure measurements from the sensing Foley catheter may be used to activate a pump so that the drainage tube is emptied. For example, when the pressure sensed in the bladder exceeds a preset number, the pump may be engaged to move urine more quickly through the drainage tube.

[0080] The control / base and / or reservoir / cassette may include an accelerometer, or other sensor, to determine when the control / cassette is level and when it is not. An alarm may sound if the control / cassette is not level. Alternatively, urine volume measurements may be adjusted to account for different angles within the system.

[0081] The bottom of the urine reservoir in the cassette may have rounded edges and may be configured such that urine empties completely from the cassette when the pinch valve is opened.

[0082] In some embodiments, the control / monitor may be integrated into the bed itself.

[0083] FIG. 10C is a detailed view showing the airlock relief mechanism and fluid collection and analysis system 1002. The screen 1110 displays a user interface including patient parameters, as well as a touch screen or other control function. The heart rate area 1152 indicates the patient's heart rate as determined by the controller based on measurements of intravesical pressure sensed by the sensing Foley catheter. The respiration rate area 1154 indicates the patient's respiration rate as determined by the controller based on measurements of intravesical pressure sensed by the sensing Foley catheter. The core body temperature area 1156 indicates the patient's core body temperature as sensed by a temperature sensor in the sensing Foley catheter or otherwise sensed. The urine volume area 1158 indicates the patient's current and / or average urine volume as determined by the controller based on urine volume measurements measured by a pressure measuring device connected to the pressure interface 1150 and / or the ultrasound transducer interface 1130. The sepsis index area 1160 indicates the patient's likelihood of sepsis as determined by the controller based on one or more collected and / or calculated patient parameters. For example, determining sepsis risk may take into account factors such as body temperature, abnormal heart rate, abnormal respiratory rate, and / or urine output. Trends in these parameters may also be used in assessing risk. For example, decreased urine output, increased heart rate, and increased or decreased body temperature may be indicative of sepsis.

[0084] Other risk assessments may be determined by the controller and displayed in addition to or instead of the sepsis index. These include risk assessments for acute kidney injury, urinary tract infection, intra-abdominal hypertension, abdominal compartment syndrome, infection risk, sepsis, acute respiratory distress syndrome (ARDS), etc. FIG. 58A shows, for example, sample risk algorithms for acute kidney injury and urinary tract infection. FIG. 58B shows sample risk algorithms for acute kidney injury, sepsis, and acute respiratory distress syndrome. Measured urine parameters may include conductance, specific gravity, urine volume, presence or absence of infection, presence or absence of bacteria, presence or absence of white blood cells, oxygen tension, etc.

[0085] Graphical indicators 1162 show historical data for any of these areas. For example, a user may be able to toggle the graphical display by touching the screen to display patient history such as urine volume, temperature, heart rate, respiratory rate, sepsis index, risk of acute kidney injury, urinary tract infection, intra-abdominal hypertension, abdominal compartment syndrome, infection risk, or any other suitable parameter. The historical time frame may be all-time, daily, hourly, or any time period set by the user. Risk factors that are out of range and therefore at increased risk may be automatically displayed here or elsewhere on the display. Alerts and / or ranges may be set by the user and may include absolute values ​​or trends over time. For example, an increase in core temperature of 2 degrees or more over a particular time frame may be visually displayed and / or an audible alarm may be sounded.

[0086] FIG. 11A shows a sensing Foley catheter system (including airlock relief mechanism, fluid drainage, collection and analysis system / control) according to an embodiment similar to that shown in FIG. 10A, in which the vent 1180 is located on the control 1018 or reservoir / cassette 1022, rather than on the vent barb (or barbs) 1182. In this embodiment, the vent 1180 is in fluid communication with the urinary drainage lumen 1012 via a vent lumen 1184 that fluidly connects to the urinary lumen 1012 at the barb 1182. In this embodiment, the barb design is simplified and the drainage tube simply has an additional lumen compared to the embodiment shown in FIG. 10A. The vent may be located anywhere in the system, and the fluid interface with the urinary lumen may be located anywhere in the system as well.

[0087] FIG. 11B illustrates a sensing Foley catheter system according to an embodiment similar to that shown in FIG. 11A. In this embodiment, a gas permeable vent / filter is incorporated into the cassette 1022 and / or control unit 1018. The vent lumen may pass along the drainage tube 1012 from the barb 1182 into the vent tube 1184. The vent lumen may terminate externally to the cassette and / or control unit, or may pass through the cassette and possibly the control unit as shown here, incorporating a gas permeable vent / filter 1180. FIG. 11B further illustrates a valve 1186. The valve may be a one-way valve that allows the flow of fluid (e.g., atmospheric pressure) through the vent lumen, through the barb or other location along the drainage tube or Foley catheter, or through the base / control unit 1018 into the drainage tube. The valve prevents fluids, such as urine and / or air, from flowing through the vent tube and potentially reaching the filter. The valve may be passive, as shown here, or may be actively controlled by the control. The valve may be located anywhere in the vent lumen, including in the barb, or anywhere along the vent tube, anywhere in the cassette, anywhere in the control, or anywhere outside of the control, e.g., anywhere on the non-patient side of the control.

[0088] In some embodiments, the valve is actively controlled via the controller by controlling the negative pressure in the drainage tube. The valve may be opened by the controller pulling negative pressure in the drainage tube lumen of the drainage tube, and the valve may be closed by the controller reducing the vacuum applied to the drainage tube (i.e., applying less negative pressure, applying zero pressure, or applying a slight positive pressure to the drainage tube lumen). Since the drainage lumen of the catheter and the drainage tube are in fluid communication with the lumen of the vent tube, the negative pressure applied to the drainage tube also acts on the lumen of the vent tube, and the valve opens when the differential pressure across the valve exceeds the crack pressure of the valve. The valve may be closed again by reducing the vacuum applied to the drainage lumen, thereby reducing the differential pressure across the valve to a pressure below the crack pressure of the valve. In this way, the controller can actively control the opening and closing of the valve in the vent tube, even when the valve itself is a passive valve.

[0089] In some embodiments, the controller may actively open the valve periodically, e.g., on a regular schedule. This is shown graphically in FIG. 11F. For example, the controller may open the valve at least every 30 minutes (represented by T1), keep the valve open for at least 15 seconds (represented by T2), and then close the valve for another 30 minutes before the cycle begins again. The difference between the vacuum applied to open the valve and the vacuum applied to keep the valve closed is represented by DIFF in the diagram. DIFF is greater than the valve crack differential pressure. Alternatively, T1 may be at least 60 minutes. Alternatively, T1 may be at least 20 minutes. Alternatively, T1 may be at least 10 minutes. Alternatively, T1 may be at least 5 minutes. Alternatively, T2 may be at least 5 seconds. Alternatively, T2 may be at least 10 seconds. Alternatively, T2 may be at least 20 seconds. Alternatively, T2 may be at least 30 seconds.

[0090] Although FIG. 11F shows the valve closing pressure at a negative pressure, the valve closing pressure may be zero or may be a positive pressure.

[0091] The length of the cycle may alternatively be variable, where T1 and / or T2 are determined as a function of the urine output flow rate. The cycle may alternatively be based on the system detecting an airlock in the drainage tube. This may be done by measuring the pressure in the system, for example the vacuum pressure in the drainage tube or the pressure at the barb.

[0092] In some embodiments, the valve 1186 may be disposed without a filter. In some embodiments, a filter may be between the drainage lumen and the valve 1186.

[0093] In some embodiments, the vent tube 1184 is integral with the drainage tube 1012 along all or a portion of the length of the drainage tube.

[0094] The valve may be a duckbill valve, umbrella valve, ball valve, dome valve, Belleville valve, cross slit valve, X-fragm valve, or any other valve suitable for medical applications. The valve may have a very low crack pressure or a higher crack pressure, but generally will be between zero and the amount of negative pressure being pulled by the vacuum pump.

[0095] 11C illustrates a sensing Foley catheter system according to an embodiment similar to that shown in FIG. 11B. In this embodiment, the vent tube includes a portion of the lumen having a smaller diameter between the barb and the valve. The smaller inner diameter tubing between the barb and the valve creates a column of air between the valve and the barb, which generally prevents urine from entering the vent tube when the vent tube valve is closed. When the vent tube valve is open, fluid flow is generally in the opposite direction (i.e., into the drainage tube lumen), which may further prevent urine from entering the vent tube.

[0096] FIG. 11D illustrates an example of a vent tube with different diameter sections. A first section 1188 is the section closest to the patient and has an inner diameter ID1 and a length L1. In this embodiment, a valve 1186 allows fluid to flow only generally from right to left, as shown by the dashed arrows. A second section 1190 is further away from the patient and has an inner diameter ID2 and a length L2. In some embodiments, L1 is smaller than L2 and ID1 is smaller than ID2. In some embodiments, ID1 is smaller than ID2, but the lengths may be different or the same. L1+L2 may be approximately the same length as the drainage tube.

[0097] In some embodiments, ID1 may be about 1.8-2.0 mm. In some embodiments, ID1 may be about 1.6-1.8 mm. In some embodiments, ID1 may be about 1.4-1.6 mm. In some embodiments, ID1 may be about 1.2-1.4 mm. In some embodiments, ID1 may be about 1.0-1.2 mm. In some embodiments, ID1 may be about 0.8-1.0 mm. In some embodiments, ID1 may be about 0.5-0.8 mm. In some embodiments, ID1 may be about 0.2-5 mm. In some embodiments, ID1 may be less than about 1 mm. In some embodiments, ID1 may be less than about 2 mm. In some embodiments, ID1 may be less than about 3 mm. In some embodiments, ID1 may be less than about 4 mm. In some embodiments, ID1 may be less than about 2 mm. Preferably, ID1 is small enough to hold the siphon for all or a portion of its length.

[0098] In some embodiments, the ID2 may be about 1.8-2.0 mm. In some embodiments, the ID2 may be about 1.6-1.8 mm. In some embodiments, the ID2 may be about 1.4-1.6 mm. In some embodiments, the ID2 may be about 1.2-1.4 mm. In some embodiments, the ID2 may be about 1.0-1.2 mm. In some embodiments, the ID2 may be about 0.8-1.0 mm. In some embodiments, the ID2 may be about 0.5-0.8 mm. In some embodiments, the ID2 may be about 0.2-5 mm. In some embodiments, the ID2 may be less than about 4 mm. In some embodiments, the ID2 may be less than about 5 mm. In some embodiments, the ID2 may be less than about 6 mm. In some embodiments, the ID2 may be greater than about 2 mm. In some embodiments, the ID2 may be greater than about 3 mm. In some embodiments, the ID2 may be greater than about 4 mm. In some embodiments, the ID2 may be greater than about 5 mm. In some embodiments, the ID2 may be greater than about 6 mm.

[0099] In some embodiments, L1 may be less than about 5 cm. In some embodiments, L1 may be less than about 10 cm. In some embodiments, L1 may be about 5-10 cm. In some embodiments, L1 may be about 10-20 cm. In some embodiments, L1 may be about 20-30 cm. In some embodiments, L1 may be about 30-50 cm. In some embodiments, L1 may be greater than about 50 cm. In some embodiments, L1 may be greater than about 1 cm. In some embodiments, L1 may be greater than about 2 cm. In some embodiments, L1 may be greater than about 5 cm. In some embodiments, L1 may be greater than about 10 cm.

[0100] In some embodiments, L2 may be about 50 to 150 cm.

[0101] In some embodiments, ID1 and ID2 may be the same.

[0102] 11E illustrates a catheter system according to an embodiment in which the vent lumen 1184 is in direct fluid communication with the fluid collection bag 1020. In this embodiment, a control including sensing functionality may or may not be present. In this embodiment, an airlock is avoided by the vent lumen venting the urinary drainage lumen 1012 using a vent 1142 in the fluid collection bag. Additionally or alternatively, the vent may be anywhere along the vent lumen. The vent lumen may extend the length of some or all of the drainage lumen. The urinary drainage lumen is fluidly connected to the drainage bag at a connection point 1192, which may include a valve 1136. The vent lumen connects to the drainage bag at a connection point 1194. The fluid collection bag 1020 of this embodiment, and potentially other embodiments, may include a rigid or semi-rigid portion 1196 to ensure that the fluid collection bag does not collapse around the connection point 1194. This embodiment may or may not include a valve 1186. The vent tube 1184 may be incorporated into the drainage tubing system or may be an add-on piece that connects at or near the barb of the Foley catheter at the connection point 1194 on the drainage bag.

[0103] FIG. 12A shows a sensing Foley catheter system according to an embodiment similar to that shown in FIG. 10A, but in contrast to the system shown in FIG. 10A, does not utilize a pressure balloon. Instead, the pressure in the bladder is measured via a urinary lumen (or other lumen) in the sensing Foley catheter. In this embodiment, the pressure lumen 1202 is connected to a vent 1204 or to another part of the system outside the patient's body and is in fluid communication with the drainage / urinary lumen of the catheter, at least periodically. In this embodiment, the sensing Foley catheter system can be used in combination with any standard Foley catheter. It is noted that any embodiment of the sensing Foley catheter system can be used in combination with a standard Foley catheter. The system shown in FIG. 12A may use a standard Foley catheter without the pressure lumen 1202 if intravesical pressure measurement is not desired.

[0104] In some embodiments of the sensing Foley system, intraperitoneal pressure can be measured using a standard or off-the-shelf Foley catheter. In this way, the controller can use a standard Foley catheter and still incorporate IAP measurements into the analysis. In some embodiments, the controller can activate a pump to introduce air or gas bubbles into the drainage line of the Foley catheter. By measuring the pressure in the drainage line via a pressure sensor, the controller can determine the point at which the gas / air bubbles leave the Foley catheter and enter the bladder. The pressure required to push the column of fluid containing the bubbles into the drainage line increases until the bubbles leave the drainage line. The pressure at which the bubbles leave the Foley catheter is equal to the intraperitoneal pressure. The fluid column can be solid or intermittent. The IAP measurement sequence can be performed periodically by the controller. This can be done before performing an airlock clearance or after performing an airlock clearance. The IAP measurement can also be performed manually by physically looking at the pressure on a gauge similar to a blood pressure cuff. The vent tube can be closed before performing this type of IAP measurement. The gas may be sterile and / or may be sterilized during transport, for example via ultraviolet light in the barb area.

[0105] In some embodiments of the sensing Foley system, an irrigation lumen may be included in the Foley catheter, or a separate irrigation catheter having an irrigation lumen may be used to irrigate the bladder. In these embodiments, the control unit of the sensing Foley system may be in communication with the irrigation pump such that the amount of irrigation fluid may be subtracted from the measured fluid volume to accurately measure urine volume (which does not include irrigation fluid).

[0106] In embodiments in which a standard Foley catheter is used in combination with a sensing Foley system, a specialized clamp can be used to clamp one or more lumens of the drainage tube without clamping the urinary drainage lumen of the drainage tube. The clamp may be configured to align the clamping mechanism with the drainage tube, for example, to close the pressure lumen but not the drainage lumen of the drainage tube.

[0107] 12B illustrates a sensing Foley catheter system according to an embodiment that does not include measurement of IAP or temperature, note that in this embodiment there is still an anti-airlock feature.

[0108] Figure 13 illustrates a sensing Foley catheter system according to an embodiment similar to that shown in Figure 12A. In this embodiment, a valve 1302 may be utilized to periodically close the pressure lumen 1202 to the urinary drainage lumen. The valve can be opened by a controller or manually when pressure measurements are to be made and closed again by a controller or manually when bladder pressure measurements are not required.

[0109] 10A, 10C, 11, and 12 show embodiments of a sensing Foley catheter system that includes a vent near the patient end of the drainage tube that allows air to enter the drainage tube if negative pressure occurs due to a siphon in the drainage tube, or a pumping mechanism, or both. Without a vent / filter, such negative pressure can lead to aspiration trauma, such as trauma caused to the mucosal lining of the bladder. Note that these embodiments are distinct from devices in which one or more vents allow air to exit but not enter the drainage tube.

[0110] The urinary drainage lumen preferably has an inner diameter of less than about 0.25 inches (about 6.35 mm) so that liquid within the lumen maintains circumferential contact with the lumen, thereby forming a seal and allowing liquid to advance when the pump mechanism is actuated. Multiple drainage lumens may be provided to prevent flow blockage in the event of a pump mechanism failure. In these embodiments, the drainage lumen is preferably generally empty, which may require continuous actuation of the pump mechanism. Alternatively, the pump mechanism may be actuated before taking a volume measurement to ensure that all liquid is drained, thereby reducing the power requirements of the device.

[0111] Some embodiments of the sensing Foley catheter system include detecting a pressure spike in the drainage line while the pressure in the body organ is constant; and generating negative pressure through the drainage line using a pump until the pressure in the drainage line equals the pressure in the body organ.

[0112] In one embodiment, the vent has a resistance to air flow that is greater than the resistance to liquid flow from the patient, so that any accumulation of liquid within the patient's body is purged into the drainage line before air enters through the vent. For example, in the case of urinary drainage, a full bladder will empty into the drainage line before air enters through the vent, so long as the resistance to air flow through the vent is greater than the resistance of urine flowing through the patient's catheter. However, the vent preferably has the least possible resistance to air flow while meeting this requirement, in order to minimize aspiration trauma.

[0113] In another embodiment, the vent provides very little resistance to airflow so that the bladder is further protected from aspiration, and the controller pump operates to clear the airlock at more frequent intervals, for example, every 1 minute, 5 minutes, or 10 minutes, to keep the drainage line clear of urine. Once the pump is running, it continues to run until it detects that no more urine is being discharged, which indicates that the bladder is completely emptied. Alternatively, the pump may run for a set period of time, for example, about 30 seconds, about 1 minute, about 3 minutes, about 5 minutes, or about 10 minutes. The controller pump may be inactive during the airlock clearance interval, or may generate a "background vacuum" (a pressure less negative than the airlock clearance pressure) during the airlock clearance interval.

[0114] The pump mechanism used may be any suitable mechanism including, but not limited to, a peristaltic pump, a diaphragm pump, a vane pump, an impeller pump, a centrifugal pump, or other suitable pump. The pump may be powered from a wall outlet, a battery, human power, or other suitable source. In some embodiments, the vacuum ranges from about 0 to about -50 mmHg. Alternatively, the negative pressure may be provided by a wall vacuum that is often present in a patient room. The pump mechanism may include a peristaltic-like pump or suction applied directly to a urine collection container. The pump may be located on the patient side of the drainage reservoir, or preferably, the pump may be located on the non-patient side of the drainage reservoir / cassette such that the drainage reservoir is between the patient and the pump. To function properly, the pump should preferably be capable of generating a negative pressure equal to the maximum fluid column height in the drainage tube, which may be half the length of the drainage tube. For a urinary drainage tube with a maximum length of 60 inches (approximately 1.52 meters), the maximum negative pressure required is approximately 30 inches H2O (approximately 0.762 meters H2O), or 56 mmHg.

[0115] Other techniques may be used to force urine through the tubes and / or systems including pulsating mechanical, vibratory acoustic, thermal, vibratory, pinching, rolling, or electromagnetic stimulation to induce movement of the drainage line and / or fluid therein. In some embodiments, the rolling stimulation includes sequential compression of multiple lumens such that the lumens are not all compressed at the same time.

[0116] In another embodiment, the airlock is eliminated by a collapsible drainage tube residing within a more rigid kink-resistant tube. FIG. 14A shows such an embodiment in its uncollapsed form. An inner collapsible drainage tube 1402 is inside an outer kink-resistant tube 1404. FIG. 14B shows an embodiment in which the inner collapsible tube is collapsed. Periodically, the drainage tube is collapsed, such as by applying positive pressure to the space between the collapsible tube and the kink-resistant tube, or negative pressure to the inside of the collapsible tube. The collapse of the drainage tube subsequently directs urine away from the patient and toward the urine collection container.

[0117] In another embodiment, the drainage lumen relief ring mechanism includes a tube with an inner diameter of less than about 0.25 inches (about 6.35 millimeters) so that air pockets cannot migrate up the length of the tube. This is due to surface tension in the smaller tube, which prevents fluid movement when one end of the tube is closed to the atmosphere (as in the bladder). In this way, the drainage tube always remains full, and because urine is incompressible, an equal amount of urine must leave the drainage tube for every amount of urine produced. In another embodiment, the inner diameter is less than 0.125 inches (3.175 millimeters). In another aspect, the drainage tube acts as a siphon, applying a small and safe amount of vacuum to the bladder. Alternatively, in a small lumen drainage tube, air can be allowed to periodically enter the lumen of the tube through a vent / valve. Negative pressure from a pump may facilitate this. Negative pressure from the pump can facilitate urine flow into the collection reservoir, thereby preventing airlock.

[0118] The use of small diameter tubing also results in less residual urine volume in the drainage tube compared to the prior art. A smaller residual volume is preferred because urine can move more quickly from the patient's bladder to the urine collection container. This rate of transport is important for measuring recently produced urine. This is especially important for patients with a low urine production rate because it takes more time for urine to be transported from the bladder to the urine collection container. For example, for a patient secreting only 10 mL / hour using a standard drainage tube (approximately 40 mL residual volume), the measurement of urine in the urine collection container will lag behind the true urine output by 4 hours. In contrast, with smaller tubes (such as tubes with approximately 5 mL residual volume), the measurement will lag behind the true output by only 30 minutes. In some embodiments utilizing small diameter lumens, with or without vents / valves, a pump is not required to provide negative pressure to the drainage line.

[0119] FIG. 15 shows an embodiment of a device suitable for drainage of chest tubes or other drainage tubes that applies constant negative pressure to the patient. These embodiments are suitable for draining urine from the bladder as well as body fluids from other cavities. Any of the elements disclosed in connection with chest tube drainage can also be applied to bladder drainage or other body cavity drainage. Fluids are drained from the patient's body via a drainage lumen 1585 that connects to a urine collection container 1582. Drainage is assisted by pulling negative pressure on the urine collection container 1582, for example by attaching a suction tube 1583 to a hospital wall suction. Suction can be applied in other ways, such as with a pump as disclosed elsewhere herein. Air enters the drainage lumen 1585 via a valve 1584 that has a crack pressure equal to the desired negative pressure. By selecting the correct crack pressure (e.g., -15 mmHg to 0 mmHg, or -10 mmHg), the pressure applied to the patient will remain at this pressure as long as the hospital wall suction / pump can generate sufficient suction at the urine collection container 1582. Preferably, the drainage lumen or lumens used to drain the chest tube are as large as possible while still maintaining a siphon. Suitable inner diameters include, but are not limited to, about ¼ inch, about 5 / 16 inch, or about ⅜ inch.

[0120] FIG. 16 shows another embodiment of the device suitable for draining chest tubes or other drainage tubes applying constant negative pressure to the patient. Fluid is removed from the patient via a drainage lumen 1688 and negative pressure is applied using a pumping mechanism 1686. A pressure sensor 1687 is provided in the drainage tube at the patient end to measure the pressure applied to the patient. The measurements taken by the sensor 1687 are sent back to a controller controlling the pumping mechanism 1686, and the pressure generated by the pumping mechanism 1686 is adjusted to keep the pressure at the sensor 1687 (and the patient) at a desired level. The pressure sensor 1687 may also be located elsewhere in the system. This sensor may also be used to passively monitor the pressure at the patient end of the tube to provide the physician with information about the level of suction being applied. In FIG. 16, the pump is on the patient side of the drainage reservoir, however, alternatively, the pump may be on the opposite side of the drainage reservoir such that the drainage reservoir is between the patient and the pump.

[0121] In another embodiment of the invention used for chest tube drainage, the volume of drained fluid is measured to provide the physician with information regarding the status of chest tube drainage. This measurement can be accomplished by any suitable means, particularly those described herein for measuring urine volume.

[0122] In addition to eliminating the airlock, some of the airlock elimination configurations detailed above have been found to effectively clear deposits and clots from the urinary drainage line. These issues plague current urinary drainage tubes, especially those with smaller lumens, and monitoring techniques in urinary drainage bags, and the present invention provides an advancement in the art by automating the clearance of these urination-blocking debris and clots. This feature is particularly useful when used in combination with pressure sensing, either at the balloon at the tip of the Foley or in fluid communication with the bladder. This allows for monitoring of pressure and vacuum within the bladder, allowing for more aggressive pumping based on actual bladder pressure until the clot / obstruction is cleared. Without this pressure / vacuum sensing, pumping of fluid in the drainage tube could result in clinical sequelae to the bladder, such as suction trauma, due to the bladder mucosa being exposed to excessive vacuum.

[0123] In another embodiment shown in Figure 17, a gas sampling lumen 1790 runs the length of the drainage tube and terminates in a gas permeable but liquid impermeable filter 1791 that remains in contact with the urine, with the meniscus 1792 of the lumen 1790 further from the patient than the filter. If measurement of oxygen, carbon dioxide, or any other gas is desired, air within the gas sampling lumen 1790 is drawn into the base 1789 of the drainage device for analysis. This configuration allows accurate gas analysis to be performed even in device embodiments that admit air into the drainage line, such as those shown in Figures 10-16.

[0124] As shown in FIG. 18, the active vent system is comprised of a vent 1802, a drainage line 1804, a urine collection container 1806, and a pump 1808. The vent side of the drainage line is connected to the patient. In one embodiment, the fluid to be drained is urine and is connected to a urinary catheter. Fluid flows from the patient through the drainage line and is collected in the urine collection container. The pump in this embodiment draws a vacuum on the urine collection container rather than acting directly on the drainage line. The pump promotes drainage by drawing negative pressure on the urine collection container, forcing the fluid through the drainage line. The urine collection container is preferably rigid to maintain a constant volume when the pump applies negative pressure. The vent on the patient side of the drainage tube is preferably a vent that allows the passage of gas (preferably air) but prevents the passage of liquids. The vent thereby prevents the patient from being subjected to substantial negative pressure by allowing atmospheric pressure into the system. Such a mechanism prevents suction trauma, for example on the bladder wall.

[0125] The pump of this embodiment may be any suitable pump for pumping gas, including but not limited to a peristaltic pump, a diaphragm pump, or a centrifugal pump. To function properly, the pump is preferably capable of generating a negative pressure equal to the maximum liquid column height in the drainage tube, which may be half the length of the drainage tube. For a urinary drainage tube with a maximum length of 60 inches (about 1.52 meters), the maximum negative pressure required is about 30 inches H2O (about 0.762 meters H2O), or 56 mmHg.

[0126] As shown in FIG. 19, an active vent system for draining bodily fluids may include additional vents. One such vent, vent 1962, may be located at the urine collection container, allowing air to escape from the urine collection container. This prevents pressure build-up as new fluid enters the container by ensuring that each volume of fluid entering the system is offset by an equal volume of air leaving the system. Another such vent, 1964, may be located between the urine collection container and the pump. This vent allows gas (preferably air) to pass through but prevents liquids from passing through, thereby preventing bacteria and viruses from passing in and out of the urine collection container and drainage tube. Preferably, this vent is sterile grade, meaning that the air passing through is considered sterile. A vent (not shown) may or may not be present at the patient end of the drainage line.

[0127] As shown in FIG. 20, pressure offset may be achieved with a single vent on the urine collection container. In this case, the vent, vent 2072, may be between the urine collection container and the pump as before, but an additional valve 2074 allows air to escape from the urine collection container in the presence of positive pressure. This valve is preferably a one-way valve that allows air to leave the system but not enter it. When the pump is activated, the one-way valve closes and air must be drawn from the urine collection container, creating a negative pressure in the urine collection container and promoting fluid flow through the drainage line. There may or may not be a vent at the patient end of the drainage line (not shown).

[0128] Infectious disease detection

[0129] FIG. 21 illustrates an embodiment of a urine collection container, chamber, or cassette that may be included in a detection Foley catheter system to detect bacteria, blood, and / or other substances in urine using UV / light / Raman spectroscopy. The cassette 2100 includes a container wall 2102, preferably rigid. Urine 2106 is collected in the cassette. An overflow area 2104 allows excess urine to drain from the cassette if urine is collected too quickly or if there is any obstacle to emptying the cassette or obstacle to emptying fast enough (e.g., in high urine flow situations). The cassette 2100 may include an optically transparent portion 2110, preferably incorporated into the outer wall of the cassette, and a reflective portion 2112, preferably on or incorporated into the inner wall of the cassette. By "optically transparent" in this context, it is meant that light of one or more required analysis wavelengths can be transmitted through the optically transparent portion. Preferably, the optically transparent portion is formed of a material that can transmit ultraviolet light, such as polymethylmethacrylate, polystyrene, acrylic, quartz, and the like. The wall thickness may need to be thin enough to allow transmission of one or more suitable UV wavelengths through the optically transparent portion. For example, the optically transparent portion may have a thickness of about 0.5 mm to about 0.7 mm. Alternatively, the optically transparent portion may have a thickness between about 0.5 mm and about 0.6 mm. Alternatively, the optically transparent portion may have a thickness between about 0.6 mm and about 0.7 mm. Alternatively, the optically transparent portion may have a thickness less than about 0.7 mm.

[0130] The UV / light transceiver 2108 transmits the appropriate wavelength of UV or other wavelength of light through the urine in the cassette via the optically transparent portion 2110 to a reflector 2112 in the cassette. The UV / light transceiver may be incorporated into or connected to the control component of the sensing Foley catheter system. The light is reflected to the UV / light receiver, which transmits the collected data to the control for signal analysis. Two or more wavelengths of UV / light may be analyzed simultaneously or sequentially. Light outside the UV range may be used in addition to light within the UV range. The volume of urine between the physical transmission and reception of light is preferably maximized for a stronger signal reflecting the concentration of one or more substances in the urine. The transceiver may be located as shown in FIG. 21 or in other areas of the cassette. The receiver is at a different location than the transmitter, and a reflector may or may not be required and may or may not be present. As the urine in the cassette is emptied frequently, ultraviolet / light absorption measurements can be collected over time, and increases and / or decreases in the levels of one or more substances in the urine can be tracked over time, in substantially or near real time. Rapid identification of infections, such as urinary tract infections and catheter-associated urinary tract infections (CAUTIs), is particularly important. UV / light sensing may also be performed at other points in the sensing Foley catheter system, including within the drainage tubing, separate sampling areas, etc.

[0131] Infections may be identified by analyzing bacteria, red blood cells, plasma, and / or white blood cells in urine using ultraviolet / light spectroscopy. FIG. 22A illustrates the various wavelengths of absorption of light by E. coli, red blood cells, and plasma in urine. The presence of plasma / white blood cells and / or bacteria in urine are both indicative of infection. The presence of red blood cells may not indicate infection. It is therefore desirable to distinguish between red blood cells and bacteria / plasma / white blood cells in urine. The spectroscopic signature of red blood cells is significantly different from the signatures of bacteria and plasma / white blood cells at a wavelength of approximately 414 nm, so analyzing the absorption of light at this wavelength can separate the red blood cell signal from the bacterial and / or plasma / white blood cell signals to identify infection. At wavelengths of 260 nm and 280 nm, the signatures of plasma and bacteria are different from each other, so these wavelengths can be used to distinguish between plasma and bacteria. However, both plasma and bacteria may be present during an infection.

[0132] Broadband spectral spectroscopy may be used over a continuous wavelength range and over time. The signals may be deconvoluted or demixed to determine the amount of analyte and / or form the basis of features for developing analytical algorithms.

[0133] Other wavelengths and other techniques can also be used to detect various substances in urine or collected / excreted bodily fluids. Ultraviolet / light absorption can also be used to detect turbidity. Dyes, drugs, or reactive substances can also be introduced into the system or coated on the inside of the system, cassette, etc. to react with substances in the urine and aid in the analysis. Any type of sensor can be used to detect the substance or quality of the collected urine, intermittently or continuously, in real time. For example, one or more sensors detecting magnesium in urine can be used to diagnose pre-eclampsia or eclampsia. A lactate sensor can be used to test for lactate (or lactate dehydrogenase) in urine. Identification of lactate in urine can be an early indicator of sepsis. The lactate sensor may include an enzymatic lactate sensor. For example, lactate sensors such as those disclosed in Weber (Weber J., Kumar A., ​​Kumar A., ​​Bhansali S. Novel lactate and pH biosensor for skin and sweat analysis based on single walled carbon nanotubes. Sens. Actuators, B, Chem. 2006;117:308-313) and / or Mo (Mo, JW, Smart, W, Lactate biosensors for continuous monitoring. Front Biosci. 2004 Sep 1;9:3384-91), both of which are incorporated herein by reference in their entirety, can be used.

[0134] Visible wavelengths may also be used. For example, a camera capturing visible light may be used to monitor collected urine over time. Images collected by the camera may be analyzed for color wavelength, turbidity, color intensity, color consistency or inconsistency, and / or intensity and / or turbidity, cloudiness, presence of blood or clots, hemolysis, air bubbles, protein, etc. Images of urine may be taken at virtually any time increment over the course of hours or days, so that the urine can be monitored for the presence or absence of factors indicative of the patient's condition, or for changes that may indicate a change in the patient's condition. For example, conditions that may be identified include dehydration (based on how yellow the urine is), bleeding (based on the presence of blood), protein in the urine (based on air bubbles in the urine), injection (based on cloudiness, air bubbles, color, turbidity, etc.), etc. When using a camera to evaluate characteristics of urine collected over time, it would be important to evaluate small amounts of recently collected urine so that the urine is not diluted with older collected urine. This can provide substantially real-time feedback on the patient's condition. To that end, the camera may be aimed at the urine at the entry point of the cassette 2100, for example, at the bottom of the drainage tube and at the top of the cassette 2100, where the drainage tube connects to the cassette 2100.

[0135] Reference colors may be included in the system, e.g., the cassette, to calibrate the camera to baseline red, blue, and green colors. For example, red, green, and blue reference areas (such as reference stickers with red, green, and blue areas) may be placed near the camera (either inside or outside the cassette) or on opposite sides of the cassette so the camera can see both. The near reference calibrates the camera to the color of no urine, and the far reference will be the same color as seen by the camera through urine.

[0136] Image processing of the images collected by the camera / wavelength detector may be performed by the controller. Possible image processing steps include classification, feature extraction, multi-scale signal analysis, pattern recognition, projection, edge or boundary detection, anisotropic diffusion, hidden Markov models, image editing, image restoration, independent component analysis, linear filtering, neural networks, partial differential equations, pixelation, principal component analysis, self-organizing maps, wavelets, filtering, noise removal, edge enhancement, contrast enhancement, morphology, dilation, erosion, Fourier transform, etc.

[0137] The control unit may issue a warning to the user if the camera detects something outside a preset range, for example, if the urine color is outside the normal range, if the system tilt is outside the acceptable range, if the system tilt angle changes more frequently than a preset frequency, if the urine turbidity is outside the normal range, or if abnormal substances such as blood are detected in the urine.

[0138] In embodiments where a visible wavelength camera is used, a live or semi-live feed of urine in the system may be remotely projected. For example, a view of the urine reservoir / cassette may be projected onto a table, computer, phone, monitor in any room or other location. This feature allows the urine to be hidden in the reservoir and / or urine bag near the patient, which may be more comfortable for the patient and their visitors. That is, real urine near the patient may be hidden or covered with an opaque material and an image feed of the urine may be displayed elsewhere. Urine in any or all of the cassettes, drainage tubes, urine bags, etc. may be hidden with an opaque material.

[0139] 22B illustrates a display 1110 on the controller / monitor 1018 according to one embodiment, which includes current values ​​and past trends for IAP, temperature, urine volume, and urine color. Urine color may be sensed via a camera as disclosed herein. Note that while colors are shown in black, white, and grayscale, actual colors may be displayed, such as yellow, orange, red, etc. Settings 2202 may be available to display different historical ranges of data, such as 1 hour, 6 hours, 12 hours, 24 hours, etc.

[0140] It is noted that in the embodiments disclosed herein, a user interface display on a controller / monitor is shown. However, the display, or components of the display, or the aggregate display may additionally or instead be displayed on a computer, mobile computer, cell phone, tablet, separate monitor / screen, etc. For example, a portion of the display may be displayed on a portable tablet, which may be used separately or docked to the controller / monitor. The tablet, phone, or other device may be synchronized with the controller in close proximity, such as using RFID. The display may display information about an individual patient and / or information about multiple patients, such as at a nurse's station. The display may display data for multiple patients individually or in aggregate. The display may also incorporate multiple different screens, accessible by toggling between the screens. Some screens / displays may require administrator login authentication, such as to adjust settings for a Foley system.

[0141] RFID or other mechanisms may also or instead be used to prevent the use of unauthorized "knock-off" disposable parts of the system. In this way, the controller / monitor can recognize disposable parts as authorized and unauthorized. The system may warn the user or may not function if there are unauthorized disposable parts. Similar ID mechanisms may be used to control elements of the system. For example, a user may pay a subscription fee to access the IAP functionality of the system. The same disposable unit may be used for those who have subscribed to the IAP functionality and those who have not, but the controller may be programmed to reflect the subscription details and the ID mechanism allows disposable IAP functionality for those who have subscribed to the functionality. The ID mechanism may prevent the IAP functionality from functioning for those who have not subscribed to the functionality. Alternatively, the controller may allow the functionality to function only once or a limited number of times for those who have not subscribed to the functionality.

[0142] Drugs or drug residues in collected urine can be detected using a suitable sensor. Other substances or properties of collected urine that can be detected include color, clarity, odor, specific gravity, osmolality, pH, protein, glucose, creatinine, nitrites, leukocyte esterase (WBC esterase), ketones, red or white blood cells, casts, crystals, bacteria, yeast cells, parasites, squamous epithelial cells, and the like.

[0143] CAUTI or infection can be identified and / or reduced by several methods including analyzing urine using spectroscopy, light wavelength analysis, etc., to identify contaminants early, reducing trauma to the bladder caused by suction, reducing urine retention in the bladder, reducing the presence of bacteria or microorganisms by using antimicrobial coatings or embedding materials such as silver, improving the accuracy of intravesical pressure measurements by reducing suction in the bladder, improving the accuracy of urine volume measurements by reducing airlocks in the system and suction in the bladder. A pressure spike due to suction in the bladder may be defined as a pressure measurement of less than about -20 mmHg. Alternatively, a pressure spike caused by suction in the bladder may be defined as a pressure measurement of less than about -10 mmHg to less than about -20 mmHg. Alternatively, a pressure spike caused by suction in the bladder may be defined as a pressure measurement of less than about -10 mmHg.

[0144] CAUTI can also be reduced by using ultraviolet light, or any effective wavelength of light, or radiation, to reduce bacteria in the urine and in the system. The urine may be treated with ultraviolet light, which disinfects the urine in the cassette, or may be treated elsewhere in the system. For example, as shown in FIG. 101A, ultraviolet light may disinfect the urine as it enters the cassette, e.g., at the entry point valve 10104, or within the cassette, or above the cassette, e.g., in the drainage tube above the cassette.

[0145] 23 illustrates a cassette including a baffle or flap 2302 according to one embodiment. The baffle / flap is to prevent urine from seeping along the inner wall of the cassette, as indicated by the dotted arrow. The baffle prevents urine from seeping past the point of the baffle, so that urine will flow back into the measurement reservoir below.

[0146] Priming

[0147] A particularly advantageous aspect of the disclosed technology to achieve high resolution signals capable of monitoring pressure profiles from a particular physiological source (such as peritoneal pressure, respiratory and heart rates, relative pulmonary tidal volume, cardiac output, relative cardiac output, and absolute cardiac stroke volume) relates to regulating and maintaining a balance of pressure on either side of the pressure interface represented by the membrane of the pressure sensing balloon. This balance of pressure may be referred to as a differential pressure. In some embodiments, the preferred differential pressure is at or near zero. In some embodiments, the preferred differential pressure may be a different value. The pressure on the outer surface of the balloon (the surface facing the inner surface of the bladder) varies depending on the physiological state of the patient. The pressure on the inner circumferential surface of the balloon (which is in fluid communication with the fluid column) is subject to degradation due to fluid leakage and incomplete sealing.

[0148] Upon initial insertion of the sensing Foley catheter, external pressure is typically applied to the fluid column and to the pressure interface to a first approximation of the pressure exerted from within the bladder on the pressure interface. The pressure signal measured across the pressure interface has a maximum amplitude when the differential pressure is approximately zero. Thus, the amplitude of the pressure signal can be used to adjust the pressure applied from the fluid column to the pressure interface. This process of applying an appropriate amount of pressure to the interface may be referred to as priming the fluid column or priming the balloon. As discussed above, the pressure on either side of the pressure interface may change, so the fluid column may require repriming or re-adjustment from time to time. The need for re-priming may be monitored by testing for small changes in pressure to achieve a maximum amplitude of the pressure signal profile. Alternatively, priming may occur automatically via the control unit on a periodic basis.

[0149] The disclosed system and method embodiments include automatic pressure adjustment by the controller. Thus, the adjustment system can detect optimal target pressure and volume for inflating the balloon by monitoring the sensed pressure signal and adding or removing air or fluid volume as needed. For example, during catheter insertion, the pressure adjustment circuitry that adjusts the balloon volume and pressure may inflate the balloon until it detects a pressure rate of physiological origin. Upon detecting that rate, the pressure adjustment controller may add or subtract minute amounts of air in a routine or programmed series of steps until the amplitude of the sensed wave is maximized. The control feedback loop between the optimally adjusted pressure (manifested as balloon pressure and volume) and the sensed physiological pressure profile is performed continuously or repeatedly as needed to ensure high fidelity measurement of physiological data. In some embodiments, the automatic pressure adjustment may run in the apparent background while physiological data is transmitted and displayed, while in other embodiments, the system may pause transmission of physiological data during the pressure adjustment sequence.

[0150] An embodiment of the disclosed technology includes a gas delivery system capable of delivering gas in a priming operation, whereby pressure can be applied to a fluid column adjacent to the proximal-facing side of the pressure interface. A gas source, such as compressed air or liquid, is held in a storage tank. Using CO2 as an example, the CO2 is controllably released from the storage tank via a pressure regulator that can step down the pressure in the tank (e.g., a pressure of about 850 psi) to a range of about 1 psi to about 2 psi. The released gas passes through a filter and a pressure relief valve set at about 2.5 psi. The pressure relief valve is a safety feature that prevents gas flow at levels above 2.5 psi in the event of failure of an upstream regulator. The CO2 exiting the pressure relief valve then passes through a first solenoid-controlled fill valve into the catheter line, and ultimately fills the balloon that constitutes the pressure-sensing interface. When the pressure in the balloon rises to 30 mmHg, the first solenoid controlled valve closes. A second solenoid controlled valve, distal to the first valve, acts as a drain valve, which can release pressure from the catheter to the target pressure. Alternatively, the drain valve can be operated until a respiratory waveform is sensed, after which the balloon is optimally primed and the valve is closed. The drain valve can be operably proportionally controlled based on voltage or pulse width modulation (PWM), so that the drain rate is slow enough to reach the target pressure and close the valve before overshooting. Alternatively, a peristaltic pump or other air pump can be utilized to fill the balloon with room air.

[0151] FIG. 24 is a graph illustrating a method for priming a pressure balloon in some embodiments. Here, a small (approximately 0.3 cc) burst of liquid volume is added to a pressure sensing balloon and the pressure inside the balloon is measured. A small volume burst of fluid is introduced until the measured pressure inside the balloon settles to a stable pressure 2401. This transition is shown at inflection point 2402. Volume bursts are introduced past this point until the measured pressure begins to increase rapidly (e.g., when the slope 2404 of the curve is greater than approximately 2 mmHg / 10 ms). This inflection point is shown at 2406. At this point, the pressure inside the balloon drops to around or slightly above the stable pressure 2401. This pressure represents the prime pressure measurement pressure in some embodiments. This process is also illustrated in the flow chart of FIG. 27.

[0152] Alternatively, priming the pressure balloon may include pressurizing the pressure balloon well above zero mmHg, then removing a small amount of air / gas / fluid and monitoring the pressure of the pressure balloon. The pressure of the pressure balloon will stabilize or plateau as it approaches the optimal primed pressure. To determine this optimal pressure, a pressure measurement is taken as the small amount of air is removed from the pressure balloon, and if the subsequent pressure measurements are essentially the same (within about 2 mmHg of each other), the balloon is at the optimal primed pressure. If the two subsequent measurements are not essentially equivalent, the pressure balloon is repressurized well above zero mmHg and the process is repeated. The pressure measurement taken when the small amount of air is removed from the pressure balloon may take between about 5 seconds and about 15 seconds to compensate for the effects of breathing on the pressure measurement. In some embodiments, the pressure signal may require a short stabilization period after the small amount of air / gas / fluid is removed from the pressure balloon before a pressure measurement is taken.

[0153] The small volume burst of fluid may be about 0.2 cc to about 0.4 cc. The small volume burst of fluid may be about 0.1 cc to about 0.5 cc. The small volume burst of fluid may be up to about 0.5 cc. The small volume burst of fluid may be up to about 1.0 cc.

[0154] FIG. 25 shows a graph depicting a method for priming a pressure balloon in some embodiments. This method is similar to the method depicted in FIG. 24, except that the pressure in the pressure sensing balloon is raised more smoothly without the burst depicted in FIG. 24. A volume of fluid is added to the pressure sensing balloon and the pressure in the balloon is measured. The balloon pressure is raised until the pressure measured in the balloon settles to a stable pressure 2505. This transition is shown at inflection point 2506. The balloon pressure rises beyond this point until the measured pressure begins to rise sharply (e.g., when the slope 2510 of the curve is greater than about 2 mmHg / 10 ms). This inflection point is shown at 2508. At this point, the pressure in the balloon drops to around or slightly above the stable pressure 2505. This pressure represents the optimal or prime pressure in some embodiments. This process is also depicted in the flow chart of FIG. 28.

[0155] FIG. 26 is a flow chart of a balloon priming process of a particular embodiment of the invention. An embodiment of the disclosed system and method includes automatic pressure adjustment by the controller. Thus, the adjustment system can detect an optimal target pressure and volume for inflating the balloon by monitoring the sensed pressure signal and adding or removing an amount of air as needed. For example, during catheter insertion, the pressure adjustment circuit, which adjusts the balloon volume and pressure, inflates the balloon until it detects a pressure rate of physiological origin. Upon detecting that rate, the pressure adjustment controller adds or subtracts minute amounts of air or fluid (approximately 0.3 cc) in a routine sequence until the amplitude of the sensed wave is maximized. The control feedback loop between the optimally adjusted pressure (manifested as balloon pressure and volume) and the sensed physiological pressure profile is performed continuously or repeatedly as needed to ensure high fidelity measurement of physiological data. In some embodiments, the automatic pressure adjustment may be performed in the apparent background while physiological data is transmitted and displayed, while in other embodiments, the system may pause transmission of physiological data during the pressure adjustment sequence.

[0156] The amount of trace air or fluid may be about 0.2 cc to about 0.4 cc. The amount of trace air or fluid may be about 0.1 cc to about 0.5 cc. The amount of trace air or liquid may be up to about 0.5 cc. The amount of trace air or liquid may be up to about 1.0 cc.

[0157] In some embodiments, priming of the balloon may be based on characteristics of the system. The pressure balloon may be inflated once, twice or more times to characterize the system including the ultrasound transducer, the pressure pump, resistance in the system, the pressure balloon, etc. The pressure balloon may be pressurized over a range of pressures to determine the characteristics of the particular system at that time. This information is then used to optimize the inflation pressure of the pressure balloon.

[0158] Loop Control Section

[0159] Certain patient parameters measured by the sensing Foley catheter system, and by other means, can affect and / or influence the treatment of the patient via the medical treatment device.

[0160] The loop control may be integrated with the control of the sensing Foley catheter system (either in the same device or in a separate device) to interpret patient parameters and control the patient's medical treatment.

[0161] For example, IAP may be used to control intravenous fluid infusion rates. If IAP becomes too high, the infusion rate can be reduced or stopped until IAP returns to an acceptable range. IAP in combination with relative stroke volume and / or stroke volume variability (variability in the magnitude of heartbeats seen, for example, in the bladder during the respiratory cycle) may allow for better control of intravenous fluid or blood product infusion, with IAP as an indicator of fluid overload and an increase in relative stroke volume and a decrease in stroke volume variability as indicators of the need for additional fluid. Urine volume may further be added to the control loop to provide an indication that fluid status has been restored with return of urine volume. Heart rate may be used in combination with respiratory rate to control infusion of medications (type of medication, infusion rate, frequency, dosage, etc.). In this way, medications may be used to guide the patient to a more stable state as determined by the heart and respiratory rate. IAP and respiratory rate may also be used to control mechanical ventilators or respirators. As the IAP rises, the positive end-expiratory pressure (PEEP) delivered by the mechanical ventilator should also rise to overcome this pressure. Indicators that ventilation is inadequate are found in tissue oxygenation and / or spontaneous breathing rate, which is seen as the underlying signal for mechanical ventilation. This signal may be extracted during mechanical ventilation, or preferably the loop controller may pause the mechanical ventilator to allow for more precise and accurate sensing of the underlying respiratory rate / respiratory drive. This IAP, tissue oxygenation and / or respiratory rate may be used to alert the provider of a worsening patient condition and / or to automatically adjust ventilator settings including respiratory rate, PEEP, %O2 inspiration and other settings. In an ideal scenario, these parameters can be used by the loop controller to monitor and control therapy in a manner informed by machine learning and algorithmic adjustments. These are just a few examples, but many combinations exist. One or more parameters can be used to control one or more therapy devices.

[0162] 29 illustrates a loop control in a patient environment according to one embodiment. In this example, the loop control receives patient parameter input from a sensing Foley catheter 2902. The sensing Foley catheter resides in the patient's bladder 2904 and includes a retention balloon 2908 and a pressure sensing balloon 2910. The sensing Foley catheter may include other sensors as disclosed herein.

[0163] The sensing Foley catheter 2902 includes a retention balloon inflation lumen, a pressure balloon sensing lumen, and a urine lumen. The pressure sensing balloon 2910 is connected to the pressure sensing lumen which is connected to a pressure transducer 2920 which may be incorporated into a control unit 2928. The urine lumen is connected to a urine output tube 2912. The urine output tube empties into a urine reservoir 2914 which may be connected to a urinary volume measuring device 2916 or may be incorporated into the control unit as disclosed herein. Additionally, urine output may be controlled by a urine pump 2918 which may be located on the urine drainage tube, may be incorporated into the control unit, or may be located on the non-patient side of the control unit as disclosed elsewhere herein.

[0164] The patient is shown with a respiratory mask 2922, which is fed by a respiratory tube 2924. The flow and composition of respiratory gas is controlled by a respirator 2926.

[0165] The loop control unit 2928 is connected to the urinary flow measurement device 2916, the urinary pump 2918, the pressure transducer 2920, and the respirator 2926 via corresponding connectors 2930, 2932, 2934, 2936. The connectors may be either wired or wireless. Alternatively, in this and other embodiments, some or all of the urinary flow measurement device 2916, the urinary pump 2918, and / or the pressure transducer 2920 may be incorporated into the control unit 2928.

[0166] In this example, the loop controller 2928 can receive patient parameter inputs from the urinary flow measurement device 2916 and the pressure transducer 2920 and use the information provided by these parameters to control the urine pump 2918 and the respirator 2926. Some parameters that the loop controller may receive from the sensing Foley catheter include IAP, respiratory rate, heart rate, stroke volume, tissue oxygenation, tissue perfusion pressure, temperature, urine analytes, urine output, and other parameters, including those disclosed herein.

[0167] For example, if the loop controller receives parameter information indicating that the patient's IAP is elevated, the loop controller may control the respirator irrigation rate, pressure, or other parameters. The loop controller may incorporate data from one or more input parameters to control one or more therapeutic medical devices. For example, based on the received elevated IAP parameter and abnormal tissue oxygenation parameter, the loop controller may control the output of the respirator 2926 and also control the urine output rate by controlling the urine pump 2918.

[0168] The loop controller continues to monitor one or more parameters of the patient and adjusts one or more therapeutic medical devices accordingly. When the patient parameters normalize, the control of the therapeutic medical device is adjusted accordingly such that the feedback loop controlled by the loop controller is a closed loop. The loop can also be manually adjusted as needed, in which case the loop may be an open loop or a semi-closed loop.

[0169] FIG. 30 illustrates another example of a loop control device in a patient environment. In this example, the patient has an intravenous (IV) line 3002 in a vein in the arm. An intravenous (IV) fluid bag 3004 is elevated to drip and / or receive IV fluid into the patient via the IV line 3002. A valve 3006 controls the flow rate of IV fluid to the patient by allowing free flow, restricting flow, or stopping the flow of fluid. Here, the valve 3006 is controlled by the loop controller 2928 via a connection 3008. The IV fluid bag 3004 may contain hydration fluid and / or medication. One or more IV infusion bags may be involved, and one or more valves may control the one or more IV infusion bags. The loop controller may control the flow and contents of one or more IV fluids to the patient based on patient parameters received by the loop controller.

[0170] 31 illustrates another example of a loop control in a patient environment. In this example, a fluid drainage line 3102 is inserted into the abdomen of a patient. Fluid from the abdomen may flow from the patient to a receptacle 3104. The flow of fluid may be controlled by a pump 3106 controlled by the loop control 2928 via a connection 3108. The loop control may control the flow of fluid from the patient to the receptacle 3104 via the pump 3106 based on received patient parameters. For example, if the IAP is abnormally high, the loop control may increase or begin the rate of fluid removal from the patient by controlling the pump 3106.

[0171] FIG. 32 illustrates another example of a loop control in a patient environment. In this example, a patient has an intravenous (IV) line 3202 in a vein in the arm. A drug infusion device 3204 controls the flow of medication to the patient via the IV line 3202. More than one drug infusion device may be used, where the drug infusion device 3204 is controlled by the loop control 2928 via a connection 3206. The drug infusion device 3204 may include any suitable fluid and / or medication. The loop control may control the flow and content of one or more medications to the patient based on patient parameters received by the loop control.

[0172] Although these examples show some of the medical treatment devices that can be controlled by the loop control unit, any type of medical treatment device can be used.

[0173] FIG. 33 is a detailed diagram showing the loop control. The loop control 2928 can receive one or more patient parameter inputs from a sensing Foley catheter or other device. These inputs include, but are not limited to, urine output volume and rate, pressure profile from the bladder, and sensor information from a sensing Foley catheter or other device. The pressure profile information from the bladder can be further analyzed to determine IAP, respiratory rate, heart rate, stroke volume, sepsis index, acute kidney injury (AKI) index, and other patient parameters. This analysis may be performed within the loop control 2928 or within a separate control connected to the loop control by either a wired or wireless connection. The connection may be via a network such as the Internet, an intranet, a WAN, a LAN, etc., or may be local, such as via Bluetooth, Wi-Fi, etc.

[0174] The loop controller receives one or more inputs and analyzes the data to determine if control of the medical treatment device needs to be altered. The one or more medical treatment devices may be controlled to bring the patient parameters into a target range. Once the patient target range is achieved, the loop controller may return the controlled one or more medical treatment devices to a standard condition. The standard condition may vary from medical treatment device to medical treatment device and from patient to patient. The target ranges of the patient parameters may likewise vary from patient to patient and from patient to patient condition. For example, the target range for respiration rate may be different depending on whether the patient is sedated or not.

[0175] In embodiments of the present technology, the infusion rate of intravenous fluids or medications may be automatically adjusted based on feedback from sensed cardiac output or respiratory rate. In one such embodiment, a patient-controlled analgesia pump may be deactivated if the respiratory rate is too low. Respiratory distress can be fatal in this group, and this safeguard could prevent overdose. An automated feedback system may also be effective in high-volume resuscitation procedures, where fluid infusion is adjusted based on intraperitoneal pressure, and an alarm and slower infusion rate in response to increased intraperitoneal pressure can prevent intraperitoneal compartment syndrome. Yet another automated feedback function may provide feedback directly to the ventilator system to provide optimal pressure of ventilation gas. In settings with increased abdominal pressure, typical ventilator settings may not provide adequate breaths for the patient. Automatic adjustment of ventilator settings based on intraperitoneal pressure feedback from this embodiment can effectively provide optimal patient ventilation. Also, embodiments of the present technology may be applied as a correction in the application or understanding of other diagnostic measurements. For example, central venous pressure may be dramatically distorted in situations of increased intraperitoneal pressure. Direct access to these data by the central venous pressure reporting system allows for automatic correction and accurate reporting of this important physiological parameter.Embodiments of the present technology may also be used in a variety of other ways to automate therapy, including infusion of fluids that may further include active agents such as pressors or diuretics, in response to increases or decreases in cardiac output or other parameters.

[0176] Other inputs and outputs to the loop control may include nutrition provided via feeding tube or intravenously, wound drainage, waste discharge, wound drainage, chest drainage, sweat, exhaled steam output, etc. Sweat may be assessed by measuring body temperature, ambient temperature, ambient humidity, or, in the case of ventilated patients, inspired air temperature, humidity. Alternatively or additionally, a skin sweat sensor may be used.

[0177] In addition to directly controlling one or more medical treatment devices, the loop control 2928 may sound alarms including audible alarms, email alarms, text alarms, pager alarms, etc. The loop control 2928 may also provide outputs to other systems for system integration, such as outputting information to an electronic health record (EHR) or other data archiving system, or other system. The loop control 2928 may also receive inputs from various EHR, EMR, or other systems.

[0178] A medical treatment may be administered to the patient as a result of the data collected and / or analyzed by the sensing Foley catheter system. This treatment may be a medication that is automatically administered via a loop control unit or may be administered manually via traditional medication methods, i.e. orally, via injection, etc.

[0179] Further medical diagnoses may be made based on the results of the sensing Foley catheter system.

[0180] specific gravity

[0181] Urine specific gravity may be measured by manometric and ultrasonic measurements using a sensing Foley catheter. Figure 34 is a plot showing how ultrasonic and manometric measurements of volume diverge with liquid density. The liquid being measured is a synthetic urine concentrate with a specific gravity of around 1.100.

[0182] For a liquid with a specific gravity of 1.000, the two measurement techniques are calibrated to provide the same volume measurement. However, as density increases, they begin to diverge. With pressure, increasing density increases the volume measurement because V=A*h and P=ρ*g*h, or V=A*ρ*g / P. With ultrasound, increasing density decreases the volume reading because V=A*(E / ρ)^(1 / 2)*t / 2, where V=A*h, v=h*2 / t, and v=(E / ρ)^(1 / 2). V: Volume A: Cross-sectional area h: height of liquid P: Pressure ρ: liquid density g: gravity V: velocity of sound t: The time it takes for the sound to reflect E: bulk modulus of the liquid

[0183] Simply put, as the liquid becomes denser, the pressure increases, causing its readings to be higher diagonally. At the same time, sound travels more quickly, distorting the ultrasound readings lower. By measuring how much it diverges, the density of the liquid can be measured. This assumes that the temperature is unchanged, but the temperature can also be monitored to correct for temperature fluctuations. Volume measurements by ultrasound and pressure can be made with a sensing Foley catheter, as can temperature measurements. Thus, by using a sensing Foley catheter in combination with a control unit, urine specific gravity can be measured.

[0184] Reduce condensation

[0185] Balloon catheters, especially those that are configured to reside within a human or animal body for a relatively long period of time, may leak over time. For example, a balloon inflated with air or another gas may leak air from the balloon over time. Alternatively, a balloon filled with a liquid may leak liquid over time. And vice versa. A balloon filled with gas or air present in fluids such as urine or blood may leak fluid into the balloon over time. This is especially true if the balloon is inflated at a relatively low pressure.

[0186] A sensing Foley catheter is one example of a balloon that is configured to be inflated at a relatively low pressure for a relatively long period of time. In this example, when the balloon is configured to measure pressure, it is inflated at a relatively low pressure and, as a result, may be manufactured from a relatively flexible and thin-walled material. The low inflation pressure and the flexible and thin-walled balloon material may allow liquid to leak into the balloon over time. Liquid in a pressure measurement balloon may adversely affect very sensitive pressure measurements, especially if the liquid migrates into the catheter lumen where the pressure measurement is made.

[0187] In one embodiment to solve this problem, a very small pore filter, i.e. a hydrophobic filter, is placed between the pressure measurement balloon and the pressure measurement lumen of the catheter. This allows the balloon to be inflated and constantly primed to maintain pressure, and pressure measurements are taken through the catheter lumen. Air and gases can pass through the filter, but fluids cannot.

[0188] Another embodiment involves forming the balloon from a material with low moisture permeability.

[0189] Another embodiment involves refreshing the gas in the balloon by applying alternating vacuum and pressure to the balloon through one lumen or through two or more lumens.

[0190] Another embodiment involves circulating the gas within the balloon by having two or more lumens access the balloon: one lumen may be used to introduce gas into the balloon and another lumen may be used to withdraw gas from the balloon.

[0191] Alternative embodiments include using a desiccant in the balloon, the balloon lumen, a gas supply to the balloon, or any combination thereof.

[0192] FIG. 35 illustrates the distal end of a Foley-type balloon catheter that may benefit from condensation reduction. In this example, the balloon catheter is configured to be placed in a patient's bladder to aid in the drainage of urine from the bladder. The catheter has a retention balloon 3506 that secures the catheter within the bladder. The catheter shaft 3502 includes multiple lumens for the catheter. An opening 3504 allows urine within the bladder to drain through the catheter and out the proximal end of the catheter (not shown). An opening 3508 allows for inflation and deflation of the retention balloon. A pressure sensing balloon 3510 inflates and deflates through an opening 3512. The pressure sensing balloon 3510 transmits pressure signals from within the bladder through a pressure lumen in the catheter shaft to a pressure transducer proximal to the proximal end of the catheter.

[0193] Under certain circumstances, over time, fluid may leak into the pressure balloon 3510. Additionally, fluid may migrate from within the pressure balloon 3510 through the openings 3512 and into the catheter shaft 3502. Fluid within the pressure lumen can adversely affect pressure measurements from the pressure balloon. As a result, it is desirable to prevent fluid from migrating from within the pressure balloon through the openings 3512 and, if possible, reduce the amount of fluid entering the pressure balloon.

[0194] FIG. 36 illustrates a filter within a balloon according to one embodiment. The filter 3602 resides between the interior of the balloon 3510 and the pressure lumen of the interior of the catheter at the opening 3512. The filter 3602 is preferably formed of a material that allows gas to pass through but not fluids. For example, the filter can be formed of a hydrophobic membrane such as Versapor®, PTFE, ePTFE, etc. The filter can be formed of a polymer such as Nylon®, or other suitable material. The pore size can be about 3 microns, about 5 microns, about 0.2 microns to about 5 microns, about 5 microns to about 10 microns. The thickness of the filter can be in the range of about 6 mils (about 0.1524 millimeters) to about 12 mils (about 0.3048 millimeters). Alternatively, the thickness of the filter can be in the range of about 1 mil (about 0.0254 millimeters) to about 6 mils (about 0.1524 millimeters). The size of the pores is related to the sensitivity of the balloon. For example, a filter with a pore size of 5 micrometers may be suitable for a balloon inflated to about 5 mmHg to about 20 mmHg, and may provide the ability to sense differential pressures to a resolution range of 0.01 mmHg. If the sensitivity of the pressure measured through the pressure balloon is low, a smaller pore filter may be used. If the sensitivity of the pressure measured through the pressure balloon needs to be high, a larger pore filter may be used.

[0195] 36 illustrates a filter in the form of a tube that surrounds and completely covers the catheter shaft at an opening 3512. The filter may be attached at its ends to the catheter shaft using any suitable adhesive or other means, such as heat shrink. The seal between the filter and the catheter is ideally gas impermeable, so that gas entering or leaving the balloon 3510 through the opening 3512 must pass through the filter 3602.

[0196] 37 shows another embodiment of the invention, which includes a smaller catheter shaft with a filter mounted within a balloon. The catheter shaft 3704 within the balloon is smaller in diameter than the catheter shaft 3706 that is not under the balloon. This prevents the diameter of the inflated balloon from increasing due to the bulk of the filter 3702.

[0197] FIG. 38 shows the embodiment shown in FIG. 37 with the balloon deflated, and it can be seen that by reducing the diameter of the catheter shaft below the balloon area, significant inflation of the balloon catheter is prevented.

[0198] 39 illustrates an under-balloon filter according to another embodiment. The filter 3902 in this embodiment does not extend completely around the catheter shaft, but instead is a flat or curved filter piece that is adhered to the catheter shaft via adhesive or other suitable means. The adhesive preferably seals the filter all around its edges without encroaching on the balloon inflation / deflation / pressure measurement opening 3512.

[0199] FIG. 40 illustrates a short length filter 4002 according to another embodiment.

[0200] FIG. 41 illustrates a balloon catheter with a filter according to another embodiment. In this embodiment, the balloon catheter has two lumens in fluid communication with the balloon. The filter 4102 covers the opening 4104, but the opening 4106 is not covered. In this embodiment, the openings 4104 and 4106 may each access separate lumens of the catheter or may access the same lumen. In embodiments where they access separate lumens, balloon inflation, deflation, and pressure measurements may be performed through either lumen. For example, pressure measurements may be made through the lumen in fluid communication with the opening 4106 until the accumulation of liquid in the lumen adversely affects the pressure measurements. At this point, the pressure transducer may be switched to the lumen in fluid communication with the opening 4104 so that pressure measurements may be made through the lumen without liquid.

[0201] Alternatively, pressure measurements may be taken through the lumen in fluid communication with opening 4106 until accumulation of liquid in the lumen adversely affects the pressure measurements. At this point, gas may be introduced into the lumen in fluid communication with opening 4106 to clear the lumen of fluid. At the same time, gas may be withdrawn from the balloon through the lumen in communication with opening 4104. In this manner, liquid is cleared from the lumen in communication with opening 4106 and pressure measurements may be resumed through that lumen. This line clearing procedure can be programmed to occur periodically.

[0202] Figure 41 shows two balloon openings 4104, 4106 on different sides of the catheter with a filter 4102 covering only one opening. Alternatively, Figure 42 shows a similar embodiment to Figure 41, except that two openings 4204, 4206 may be side-by-side such that a filter 4202 covers only one of the openings.

[0203] 43 illustrates an embodiment of the present invention in which a filter 4302 covers a larger opening 4304. A larger opening may be desirable to obtain more accurate pressure readings from the balloon. Additionally, the addition of filter 4302 may allow for a larger opening due to the extra conformity that the filter, and perhaps its adhesive means, provides to the area of ​​the catheter surrounding the opening 4304.

[0204] Figure 44 illustrates an embodiment of the present invention in which a filter 4402 is attached to a catheter shaft via a heat shrink tubing segment 4404. This provides an air-tight seal between the filter and the catheter while ensuring that the catheter opening 4406 remains clear.

[0205] FIG 45 shows an embodiment similar to FIG 44 in which the catheter shaft is lowered under the balloon area. This allows the balloon to be deflated without causing a bulge in the catheter to which the filter is attached. The filter 4502 is attached to the catheter shaft via a heat shrink tubing segment 4504. This allows for an air tight seal between the filter and the catheter while ensuring that the opening in the catheter remains clear.

[0206] FIG. 46 illustrates an embodiment of the present invention in which a filter 4602 is attached inside the opening of the catheter.

[0207] FIG. 47 illustrates an embodiment of the invention in which the balloon has two access lumens 4702 and 4704. In this embodiment, the balloon catheter has two lumens in fluid communication with the balloon. In this embodiment, the openings 4702 and 4704 may each access a separate lumen of the catheter or may access the same lumen. In embodiments in which they access separate lumens, balloon inflation, deflation, and pressure measurements may be performed through either lumen. For example, pressure measurements may be taken through the lumen in fluid communication with opening 4702 until accumulation of liquid in the lumen adversely affects the pressure measurements, or for a set period of time. At this point, gas may be introduced into the lumen in fluid communication with opening 4702 to clear the lumen of fluid. At the same time, gas may be withdrawn from the balloon through the lumen in fluid communication with opening 4704. The reverse is also true, i.e., fluid may be introduced into the lumen in fluid communication with opening 4704 and removed from the lumen in fluid communication with opening 4702. In this manner, liquid may be cleared from the lumen communicating with opening 4702 and pressure measurements may be resumed through that lumen. This line clearing procedure can be programmed to occur periodically. Although openings 4702, 4704 are shown opposite one another here, the openings may also be staggered.

[0208] Figures 48 and 49 show two different pressure balloon configurations, although any suitable configuration and / or shape may be used. Depending on the balloon material, the balloon may be manufactured differently. Some materials lend themselves to blow molding, while others lend themselves to dip molding. Other manufacturing techniques, such as resistive heat sealing, may be used as well. Figure 48 shows an example of a blow molded balloon. Figure 49 shows an example of a dip molded balloon.

[0209] Some examples of materials from which the balloon may be made include urethane, polyurethane, polyethylene, nylon, polyvinylidene fluoride, or any other suitable polymer or other material, or any combination of materials.

[0210] Balloon coatings may also be utilized to reduce the fluid permeability of the balloon, examples of such coatings include poly(p-xylylene) polymers, or parylene.

[0211] In some embodiments, it may be desirable to prevent any water vapor from entering the pressure balloon. In these embodiments, a water or fluid impermeable material may be used for the balloon. Some of the materials described herein are suitable. In addition, biaxially oriented polyethylene terephthalate (BoPET), often sold under the trade name Mylar®, may be used. Metallized polymers or other suitable materials may also be used.

[0212] In some embodiments, the sensing Foley-type catheter is configured to report the presence of water droplets or other obstructions in the air-filled lumen (e.g., pressure lumen) and then treat or resolve the water droplets. In particular, in a hypothermic environment, moisture in the air lumen may condense and form obstructive water droplets. Water droplets in an air-filled lumen (or air bubbles in a water-filled lumen) may disrupt or complicate the pressure signal due to the surface tension of the water. Thus, the pressure transmission lumen in some embodiments of the disclosed technology may include hydrophilic elements (e.g., a coating on the wall of the lumen itself, or hydrophilic fibers extending the length of the lumen, etc.) to direct moisture away from the lumen in order to maintain a continuous, uninterrupted air channel. In some embodiments, a hygroscopic composition (e.g., silica gel) may be used along the air insufflation line or within the air insufflation lumen itself to capture water or humidity. In some embodiments, a hygroscopic composition may be included in the catheter so that the air insufflation circuit does not need to be serviced to replace this material.

[0213] In some embodiments, dry air or gas may be used within the pressure lumens and pressure balloons to prevent moisture accumulation.

[0214] In some embodiments, hydrophobic or hydrophilic coatings may be used on the pressure lumen and / or the pressure balloon.

[0215] Gas Content

[0216] Another embodiment involves measuring the relative oxygen or other gas content of urine or tissue using a hydrophobic filter or membrane as an interface with the urine in the bladder or the mucosal lining of the urethra.

[0217] In some embodiments of the sensing Foley catheter, it is desirable to measure gas-containing tissue and / or urine, or changes in gas content over time. Gases that may be of interest include oxygen, carbon dioxide, nitrogen, gases associated with anesthesia, or other gases. In some embodiments, the membrane is permeable to gases but not to liquids, for example, a hydrophobic membrane, or other suitable membrane may be used. The pore size of the hydrophobic membrane may be about 5 micrometers. Alternatively, the pore size of the hydrophobic membrane may be about 3 micrometers to about 7 micrometers.

[0218] 50 illustrates a sensing Foley catheter with an oxygen permeable membrane. A retention balloon 5002 is in fluid communication with an inflation / deflation port 5010. Urine flows through the catheter through an opening 5004 and out a port 5012 that is in fluid communication with the opening 5004. A pressure sensing balloon 5006 is in fluid communication with a lumen 5014. A gas permeable membrane 5008 covers an opening at the distal end of the catheter that is in fluid communication with a lumen 5016.

[0219] Figure 51 illustrates a sensing Foley catheter with an oxygen permeable membrane similar to that shown in Figure 50, except that a membrane 5108 is between the pressure sensing balloon 5106 and the retention balloon 5102. The opening 5104 for urine may be located anywhere distal to the retention balloon 5102.

[0220] Figure 52 illustrates a sensing Foley catheter according to one embodiment in which a membrane 5204 is incorporated into a gas sensing balloon 5202. In this illustration, the gas sensing balloon 5202 is distal to a pressure sensing balloon 5206, however, another embodiment is shown in Figure 53 in which this is not the case. The gas sensing balloon 5202 may be formed from silicone, polymer, or any other suitable material.

[0221] The membrane material may be similar to the hydrophobic membrane material described in other embodiments herein. The membrane is permeable to gas, i.e., one or more specific gases, but not to liquids such as urine. In this manner, gas can pass through the membrane into the catheter to measure the gas content of the tissue and / or urine, and / or changes in gas content over time. Measured gases include gases such as oxygen, nitrogen, and carbon dioxide.

[0222] The catheter may be placed within the patient's body such that the membrane is in either the bladder or the urethra. Although the membrane is shown here on a sensing Foley catheter having a pressure sensing balloon, the gas permeable membrane may be placed on any intraluminal catheter, including catheters residing within blood vessels or other body cavities. The membrane may be in direct or indirect contact with fluids, gases, or body tissue.

[0223] 54 illustrates a control that controls the measurement of oxygen or one or more other gases. The control is typically located outside the patient's body and connected to the catheter via a port, such as a port that connects to lumen 5016. The control may also control the pressure sensing function, etc., of a sensing Foley catheter, or may be a separate control.

[0224] Here, gas measurement control 5402 is shown along with a representation of a catheter 5404 and a gas transfer membrane 5406. Gas measurement control 5402 includes an air or gas inlet 5408, an air or gas exhaust 5410, a pump 5412, an oxygen or other type sensor 5414, and a check valve 5416.

[0225] In this embodiment, a pump 5412 periodically pushes a small amount of air, or other gas, through the tubing and into the catheter. The air passes through a membrane "window" 5406, and the oxygen content of the air varies based on the oxygen content of the mucosal lining (if the gas transfer membrane is in the urethra) or urine (if the gas transfer membrane is in the bladder). Further downstream (back into the gas measurement control box 5402), a fiber optic or other type of oxygen sensor is used to measure the percentage of oxygen in the air. The pump may only run for a short period of time to allow time for the air in the system to equilibrate with the tissues / fluids.

[0226] The check valve 5416 helps prevent the air passing through the system from mixing with outside air or air from previous measurement intervals.

[0227] There may be cases where the measured oxygen, or other gas content is very low. The measurements may indicate either absolute or relative gas levels. For example, the measurements of the gas measurement control may indicate the relative oxygen content in the patient over time to indicate changes in the patient's condition.

[0228] FIG. 55 is a schematic diagram illustrating how the gas measurement control interacts with a catheter to measure the gas content of urine or patient tissue. Catheter 5502 includes a urine drainage lumen 5504 and gas measurement lumens 5506, 5508, which are in fluid communication with a gas transfer membrane 5510. Lumen 5506 contains air or other gas entering the catheter, and lumen 5508 contains air or other gas exiting the catheter after a carrier gas has passed through the gas transfer membrane. The level of oxygen or other gas in the exiting gas is measured to determine the oxygen level or changes in oxygen level in the patient's urine and / or tissue. Incoming gas measurement lumen 5506 may be open to the atmosphere or other source, or may be a closed system such that gas in lumens 5506 and 5508 is continuously circulated such that changes in gas content may be easily determined over time. That is, air or gas inlet 5408 and air or gas exhaust 5410 in FIG. 54 may be fluidly connected to one another.

[0229] If the incoming gas measurement lumen 5506 is open to atmosphere, the pump may be run intermittently so that the gas in the gas measurement lumen has more time to equilibrate across the membrane surface, resulting in a higher intermittent concentration of the measurement gas, which allows for more sensitive measurements.

[0230] The pump can be run continuously or intermittently, whether the system is closed or open, but more sensitive measurements will be obtained when the system is run intermittently in open mode. In closed system mode, trends will become more apparent as the measurement gas in the system equilibrates with the gas levels in the urine, body fluids, or tissues being measured.

[0231] In this embodiment, the urine lumen and the gas measurement lumen are separate, however, a gas transport membrane may also be located between the urine lumen and the gas measurement lumen, as shown in FIG 56, where the gas transport membrane 5602 is in fluid communication with the urine lumen.

[0232] 57A and 57B show an embodiment of a gas measurement add-on member. The gas measurement member 5702 may be inserted between the sensing Foley catheter 1000, or any Foley catheter, and the urinary drainage tube 1001, or any urinary drainage tube. The gas measurement member 5702 includes a hydrophobic filter 5704, which may be formed from materials disclosed elsewhere herein. The gas inlet lumen 5706 and the gas outlet lumen 5708 allow gas to pass over the filter 5704, which is in gas communication with the urine in the drainage system. Air or gas in the vicinity of the filter 5704 is very quickly equilibrated with the gas in the urine in the drainage system. FIG. 57B shows the path of air flow across the filter 5704. The gas outlet lumen 5708 is in fluid communication with a control (not shown here) that analyzes the gas in the lumen for one or more gases of interest. The gas inlet lumen 5706 may be open to atmosphere, another gas, or may be in a closed loop with the gas outlet lumen 5708 in the control. The control may be the same control that measures urine volume as described elsewhere herein, or it may be a separate control. The lumens 5706, 5708 may be integrated into the drainage tube 1001 or may be separate. The gas measuring member 5702 may be a separate member as shown here, or may be integrated into the vent barb 1016. The gas measuring member 5702 may alternatively be located anywhere in the system.

[0233] Detecting / determining specific symptoms

[0234] FIG. 58A shows a table listing combinations of parameters that allow fingerprints or labels (combinations of parameters) for different indicators of AKI (prerenal, intrinsic, and obstructive). In addition, there may be fingerprints or labels for the timing of parameter changes, which may also determine the cause of AKI (e.g., it is plausible that some parameters change more quickly in intrinsic AKI caused by glomerulonephritis versus intrinsic AKI caused by acute tubular necrosis). This multi-parameter approach may facilitate the selection of effective therapies for treating AKI, since effective therapies differ depending on the cause of AKI (e.g., recombinant alkaline phosphatase is effective for treating intrinsic (septic) AKI, but not for treating non-septic AKI).

[0235] FIG. 58B is a table listing parameter combinations that allow fingerprints or signs (combinations of parameters) for different indicators of sepsis, AKI, and acute respiratory distress syndrome (ARDS). These signs include increases, decreases, or both in various patient parameters such as urine volume, heart rate, respiratory rate, temperature, stroke volume, and abdominal perfusion pressure. Abdominal perfusion pressure is the mean arterial pressure (MAP) minus the intraperitoneal pressure (IAP). The mean arterial pressure is equal to the diastolic pressure (DP) plus 1 / 3 the pulse pressure (PP). (Pulse pressure is equal to the systolic pressure minus the diastolic pressure) In short, MAP=DP+1 / 3PP.

[0236] Other patient parameters may be used. One, some, or all of the relevant parameters may be used by the control unit to communicate a diagnosis and / or risk to a user or another device. The patient parameters captured by the sensing Foley catheter system may be used by themselves or in combination with parameters obtained elsewhere, such as information from an electrocardiogram, a blood pressure measuring device, or an EMR.

[0237] The sensing Foley catheter system monitors real-time, automatic, and precise physiological parameters for early detection of various disease states. Real-time multivariate (point values) and time series (trend) analysis of these high frequency data streams may be utilized to inform machine learning-based models to develop sensitive physiological markers for early onset of sepsis (or other disease state determinations). This allows for earlier diagnosis and intervention, improving clinical outcomes. The markers associated with data related to physiological changes occurring before and / or during the onset of a particular disease state can be continuously refined using machine learning via artificial neural networks to strengthen relevant parameters, weaken less relevant parameters, and build or break connections. This allows the controller to utilize algorithms to distinguish disease states from one another and normal pathology from other pathologies.

[0238] In some embodiments of the present invention, urine volume may be measured immediately after administering a diuretic to the patient. This type of test can be a strong indicator of whether an AKI patient will progress to a more severe stage and / or die. If the patient's urine volume increases after administration of a diuretic, this indicates that the patient is less likely to progress to a more severe stage of AKI. If the patient's urine volume does not increase significantly after administration of a diuretic, this indicates that the patient is more likely to progress to a more severe stage of AKI. According to the present invention, urine volume can be measured quickly and accurately in real time. Therefore, a response to a diuretic can be detected more quickly (within minutes instead of hours) than with conventional urine measurement techniques.

[0239] The test can be automated with a controller that provides a controlled dose of diuretic and then monitors urine output over minutes or hours, preferably only minutes. The diuretic administered can be furosemide or other suitable loop diuretic or other diuretic. Diuretic can be administered and data collected as disclosed in Chawla LS, Davison DL, Brasha-Mitchell E, Koyner JL, Arthur JM, Tumlin JA, Shaw AD, Trevino S, Kimmel PL, Seneff MG. Development and standardisation of a furosemide stress test to predict the severity of acute kidney injury. Crit Care. 2013 Sep 20;17(5):R207, which is incorporated herein by reference in its entirety.

[0240] In addition to detecting AKI, the present invention can detect urinary tract infections (UTIs), as indicated by decreased oxygen tension, decreased carbon dioxide levels, increased specific gravity, and relatively stable urine volume and conductance. By combining urinary markers to create a UTI fingerprint, UTIs can be detected in the absence, and potentially even in the presence, of AKI. The UTI fingerprint can alert a physician to the presence of a UTI.

[0241] In addition to detecting AKI and UTI using the described parameters, these parameters can be used in combination with measurements of intra-abdominal pressure (IAP), respiratory rate (RR), heart rate (HR), cardiac output (CO), relative stroke volume (RSV), temperature (Temp), pulse pressure (PP), urinary conductance (UC), urine volume (UO) and / or stroke volume (SV), which are already used to detect conditions such as intra-abdominal hypertension (IAH), abdominal compartment syndrome (ACS) and sepsis. The addition of IAP, RR, HR, CO, RSV, Temp, PP, UC, UO and / or SV measurements to the algorithms described herein increases the sensitivity and specificity of detecting AKI or UTI. Meanwhile, the addition of measurements obtained by the present invention to the IAP, RR, HR, CO, RSV, Temp, PP, UC, UO and / or SV measurement algorithms may increase the sensitivity and specificity of detecting IAH, ACS or sepsis. Other clinical applications include trauma and burn treatment.

[0242] In addition to absolute measurements of IAP, RR, HR, CO, RSV, Temp, PP, UC, UO, gas concentrations and / or SV, trend data of these parameters may also be used to detect IAH, ACS, sepsis or other conditions. For example, the slope of the values ​​of these parameters over time and / or the variability of the values ​​of the parameters over time may be used. Another example of using data trends is using pulse pressure waveform analysis and pulse wave velocity (or pulse transit time). Pulse wave transit time may be measured by capturing a cardiac signal, such as an electrocardiogram, from leads on a sensing Foley catheter and / or other locations and measuring the time it takes for the pulse wave pressure signal to travel to the bladder. Multiple parameters and / or parameter trends may be used to determine the presence of IAH, ACS, sepsis or other conditions.

[0243] Examples of uses for trend data include:

[0244] -Decreasing UO with stable vitals (or not) may indicate acute kidney injury. Decreasing stroke volume may indicate renal ischemia. A sudden increase in urine output with stable vitals may indicate toxic acute kidney injury.

[0245] -Increasing respiratory rate with decreasing stroke volume may indicate pulmonary embolism, hemorrhage, or other volume reduction.

[0246] An increased respiratory rate in the presence of stable vitals may indicate impending airway obstruction.

[0247] - Decreased respiratory rate in the presence of stable other parameters may indicate a narcotic overdose, which is a major problem in patient-controlled analgesics.

[0248] - Elevated intraabdominal pressure (IAP) and increased urinary output in the presence of stable stroke volume may be indicators of impending fluid overload.

[0249] The increase in IAP and the decrease in cardiac output associated with a decrease in UO may be indicative of cardiopulmonary insufficiency, which may be due to fluid overload or sepsis.

[0250] The present invention can be used in various hospital settings (e.g., emergency room, operating room, intensive care unit, ward). At any time, the device can be used to monitor the progression of AKI, whether it is improving or declining. The algorithm alerts the physician to new cases of AKI or changes in the status of AKI. The device may be placed before kidney damage occurs (e.g., in patients undergoing cardiac surgery to detect if kidney damage begins during surgery) to detect the onset of AKI. It may be placed when there is already damage to the kidney to determine the extent of the damage at that time. The device may also be used to monitor the response of treatment / intervention (e.g., renal replacement therapy, fluid resuscitation, etc.).

[0251] Alternative Embodiments

[0252] In embodiments of the present technology, patient movement may be reported in the detection or diagnosis of seizure disorders. In this embodiment, pressure fluctuations may trigger an electroencephalogram or recording device to allow monitoring of intense periods during suspected seizure episodes. Additionally or alternatively, pressure, acoustic or other sensors may be used to detect peristalsis, patient movement, seizure activity, patient tremors, cough frequency, cough severity, sleep duration, sleep quality, vocalization detection, patient compliance (movement or lack thereof) and alert medical personnel that the patient is not moving and needs to turn or roll over. This movement related information may also be relayed to devices such as hypothermia devices, drug delivery devices, etc. to control or mitigate seizure activity, tremors and / or coughing.

[0253] In some embodiments, the sensing Foley-type catheter is configured to report the presence of water droplets or other obstructions in the air-filled lumen (e.g., pressure lumen) and then treat or resolve the water droplets. In particular, in a hypothermic environment, moisture in the air lumen may condense and form obstructive water droplets. Water droplets in an air-filled lumen (or air bubbles in a water-filled lumen) may disrupt or complicate the pressure signal due to the surface tension of the water. Thus, the pressure transmission lumen in some embodiments of the disclosed technology may include hydrophilic elements (e.g., a coating on the wall of the lumen itself, or hydrophilic fibers extending the length of the lumen, etc.) to direct moisture away from the lumen in order to maintain a continuous, uninterrupted air channel. In some embodiments, a hygroscopic composition (e.g., silica gel) may be used along the air insufflation line or within the air insufflation lumen itself to capture water or humidity. In some embodiments, a hygroscopic composition may be included in the catheter so that the air insufflation circuit does not need to be serviced to replace this material.

[0254] In some embodiments of the disclosed technology, air may be intermittently (automatically) injected and extracted into the pressure sensing balloon so that the balloon is in a constant optimally primed state, as described in more detail above. In the case of wicking fibers or hydrophilic coatings in the lumen, air extraction can also help remove and capture any water from the air line. In the example of a liquid-filled lumen, having hydrophilic fibers or a hydrophilic coating on the inside of the pressure lumen provides a similar advantage in that this lumen can handle air bubbles. In this example, air bubbles can distort the signal, but the surface tension of the air-water interface is dissipated by the hydrophilic coating in the catheter lumen.

[0255] Additionally, in the case of liquid and / or air filled lumens, custom extrusions and lumen shapes can also be used to prevent blockage. In some embodiments of the present technology, for example, a Foley type catheter may have a lumen that is star-shaped in cross-section. Such lumens are generally immune to blockage by water droplets because the droplets tend to clump on themselves and displace from the hydrophobic walls. This action tends to disable the filling of the cross-sectional space, allowing air channels around the droplets to remain patent and communicate to the sensor. The same logic applies to air bubbles in water in a hydrophilic star-shaped water lumen. In this example, the hydrophilic liquid clings to the walls, allowing a continuous water column in the center of the lumen with no air bubbles. The same is true if a hydrophobic liquid is placed in a hydrophobic lumen. In some embodiments, the catheter may include an air channel and a sensor integrated within the catheter itself or within the fluid lumen that can send pressure back to the sensor.

[0256] The drainage tube may be a multi-lumen tube to accommodate a urinary drainage line, a pressure lumen, and a thermocouple wire, with one end connected to the barb and the other end connected to the control unit.

[0257] The Foley catheter may be extruded with BaSO4 and may be affixed with radiopaque markers for fluoroscopic monitoring.

[0258] The thermistor located at the tip of the catheter may be fixed in place using a number of extrusion profiles and assembly techniques.

[0259] In some embodiments, the sensing Foley catheter can include a blood pressure sensing element that can take any of several forms. In one embodiment, the blood pressure sensing element includes a pressure delivery balloon (either a separate dedicated balloon or a balloon in fluid communication with the device retaining balloon or the pressure sensing balloon) that can be optically analyzed when inflated to determine at what pressure the blood vessels in the bladder or urethra are blanked and blood flow is stopped. This approach reads the perfusion pressure of the tissue adjacent to the pressure delivery balloon, such reading reflects both systemic blood pressure and vascular resistance. The perfusion pressure device of this embodiment can be used for early detection or monitoring of various acute or emergency medical conditions such as sepsis, shock, hemorrhage, etc., and can be particularly advantageous in detecting these conditions early. In predicting sepsis, an embodiment of the present invention can receive white blood cell count information to better predict sepsis.

[0260] Other modalities may be used to detect tissue being blanked or ischemic as well, with a common methodological aspect being the intermittent expansion within a lumen, cavity or body tissue to constrict the vasculature.Embodiments of this device and associated methods can also be used to detect perfusion pressure in other regions of the body using intermittently expandable members and optically detect blood flow or the presence of blood.

[0261] Tissue perfusion information may be provided by sensors placed on the shaft of the catheter to contact the urethral wall when the catheter is in place. These sensing techniques may include microdialysis, pyruvate, lactate, pO2, pCO2, pH, perfusion index, near infrared spectroscopy, laser Doppler flowmetry, urethral capnography, and orthogonal polarization spectroscopy. Any of these tests may be performed on the urine or the bladder wall itself to generate a measurement of tissue perfusion.

[0262] Another embodiment of the sensing Foley catheter system includes a relief ring mechanism according to one embodiment that includes a device and / or port for positive air flow near the beginning of the drainage line. The positive air flow encourages drainage by forcing urine into the drainage line. The positive air flow device may include a one-way valve at the end of the urinary catheter that allows urine to flow only toward the urine collection device and prevents air from entering the catheter.

[0263] In some embodiments, the urine clearing mechanism includes a coating on the inside of the urinary drainage tube to reduce surface tension and facilitate drainage, hi one aspect, the coating is a hydrophobic polymer, including but not limited to PTFE or FEP.

[0264] In yet another embodiment, the relief ring mechanism includes a tubular hydrophobic vent filter that can be inserted into the drainage lumen of the device to allow air to escape throughout its length. Segmented hydrophobic vents can also be incorporated at set intervals to ensure air is expelled from the tube as it passes through these areas. In this embodiment, the hydrophobic vents are spaced at least 1-2 feet apart to prevent submersion of the vent in urine. By providing redundancy, the multiple vents / filters prevent failure of one filter / vent due to its submersion. In an ideal configuration, the vents would be PTFE or ePTFE material and secured to the tube with barbs or grommets at intervals for ease of manufacture. In an alternative embodiment, the vents take the form of slits or spirals through the length of the drainage tube, allowing air to escape the tube at any point. This prevents position dependency of the drainage tube in preventing and / or eliminating airlocks.

[0265] In an alternative embodiment, air lock is prevented by an expandable drainage tube that prevents air pockets from forming in the higher parts of the tube and urine from collecting in the lower parts. The expandable tube can prevent this by keeping the tube as straight as possible between the urinary catheter and the urine collection bag. In one aspect, the expandable drainage tube is configured with multiple telescopic sections that can expand or collapse to accommodate the distance from the patient to the collection bag. In another aspect, the drainage tube is pleated to form an accordion, allowing it to expand or collapse or deform as needed. In yet another aspect, the tube is coiled. In yet another aspect, the drainage tube is retractable by a spring coil that wraps the tube around a wheel to the appropriate length.

[0266] Relative cardiac output and relative tidal volume may also be calculated based on the deflection of the pressure sensor and / or other force gauge. If sampled at a sufficient frequency (e.g., 1 Hz or higher), respiratory motion can be quantified in a relative manner to the amplitude of motion during catheter placement. Larger motion is generally associated with heavier breathing and higher peritoneal pressure in settings where the baseline drifts upwards. Small peaks on the oscillating respiratory wave caused by the beating heart may be tracked similarly using faster sampling rates (e.g., 5 Hz or higher), and the amplitude of this wave may be used to measure relative cardiac output in settings of known stable peritoneal pressure, absolute stroke volume and / or cardiac output in settings of relatively constant peritoneal pressure.

[0267] Intra-abdominal or bladder pressure sensed by one embodiment of the disclosed technology may be used to sense the level of patient movement (e.g., as it may vary between substantially no movement and high levels of movement) and report the level of movement to a medical professional. Short bursts of peaks and valleys in bladder pressure activity may serve as a proxy for body movement in that such a bladder pressure profile is a strong indicator that the patient is using their abdominal muscles, for example, to sit up or get out of bed. This embodiment may be particularly beneficial for patients at risk of falling. In the case of a patient at risk of falling, a medical professional may be notified that the patient is sitting down and respond accordingly. Alternatively, the device may be used to report patient inactivity and / or lack of patient movement.

[0268] Multiple pulse oximetry elements allow for the determination of blood oxygen concentration or blood oxygen saturation, and the elements can be placed anywhere along the urethral length of the catheter. In some embodiments, one or more sensors are placed within the tube of the device to ensure close proximity to the urethral mucosa. This technique allows a medical professional to decompress the bladder with a urethral catheter and repeatedly and accurately obtain pulse oximetry data. The power source for the pulse oximetry may be incorporated within the urine collection receptacle or may be incorporated within the catheter itself. In some embodiments, the pulse oximeter is reusable and the catheter interface is disposable; in this arrangement, the pulse oximeter is reversibly attached to the disposable catheter and removed when oxygen measurements are no longer desired. An embodiment of the sensing Foley catheter may include an optically clear or sufficiently clear channel for the oximetry signal, such as a fiber optic cable, a transparent window, and an interface for a reusable oximeter. This method and device for urethral pulse oximetry may be used in combination with any of the other embodiments detailed herein, or may be used alone.

[0269] To prevent infection, antimicrobial coatings or materials impregnated with antimicrobial compounds may be used on the sensing Foley catheter. Examples of antimicrobial coatings / materials include silver, silver citrate, parylene, or other suitable materials.

[0270] Pulmonary blood volume variation may also be determined by a sensing Foley catheter system to aid in the assessment of the presence or risk of heart failure. A decrease in left ventricular function may result in an increase in pulmonary blood volume (PBV) or a decrease in pulmonary blood volume variation. PBV variation is defined as the change in PBV over time during the cardiac cycle. PBV may be determined as the product of cardiac output and pulmonary transit time (PTT). Cardiac output may be determined as the product of stroke volume and heart rate, where stroke volume is the area under the flow-time curve for one cardiac cycle. Pulse transit time may be obtained by looking at the delay between the QRS complex of the electrocardiogram and the appearance of the signal in the bladder. The electrocardiogram signal may be obtained from separate electrocardiogram leads, leads incorporated into the sensing Foley catheter, leads incorporated into the catheter insertion kit, or elsewhere. An electrocardiogram lead would also be able to read the electrocardiogram signal from within the urine, anywhere in the system. Two leads may be used to more accurately measure pulse transit time.

[0271] It has been shown that stroke volume, ejection fraction, and PBV variability are reduced after myocardial infarction, with the greatest changes observed in PBV variability. Therefore, determining PBV variability and identifying a decrease in PBV variability may be a strong indicator of heart failure or the risk of heart failure.

[0272] Data collected by the sensing Foley catheter system may be stored in a database and analyzed for trends or other uses. The data may include clinical data and / or device data. For example, data may be collected from multiple patients and aggregated anonymously to better treat, monitor, or predict future patient behavior. For example, data collected over time related to heart rate, respiratory rate, temperature infection, etc. may be aggregated by the control unit and analyzed to find trends, such as relationships between various parameters and outcomes. For example, a particular trend in temperature, alone or in combination with other parameters, may be a predictor of infection, development of sepsis, ARDS and / or AKI. FIG. 58 shows some well-known examples, but other, currently unknown trends may emerge from the aggregated patient data.

[0273] Data collected by the sensing Foley catheter system may be integrated with an electronic health record (EHR) or electronic medical record (EMR) and / or other systems. Data collected by the sensing Foley catheter system control unit may interface directly or indirectly with the EMR / EHR system. Data such as patient demographic and medical history data from the EMR / EHR may also be integrated with the sensing Foley catheter system.

[0274] Data Processing System Example

[0275] FIG. 60 is a block diagram illustrating a data processing system that may be used in any embodiment of the present invention. For example, system 6000 may be used as part of a controller, as shown in some embodiments herein. Although FIG. 60 illustrates various components of a computer system, it is not intended to represent a particular architecture or manner of interconnecting the components, and thus such details are not germane to the present invention. It will also be understood that network computers, handheld computers, mobile devices, tablets, mobile phones, and other data processing systems having fewer components, or perhaps more components, may also be used in conjunction with the present invention.

[0276] As shown in Figure 60, one embodiment of a data processing system, computer system 6000, includes a bus or interconnect 6002 coupled to one or more microprocessors 6003 and ROM 6007, volatile RAM 6005, and non-volatile memory 6006. The microprocessor 6003 is coupled to a cache memory 6004. The bus 6002 interconnects these various components together and also interconnects these components 6003, 6007, 6005, 6006 to a display controller and display devices 6008, as well as input / output (I / O) devices 6010, such as mice, keyboards, modems, network interfaces, printers, and other devices known in the art.

[0277] Typically, input / output devices 6010 are coupled to the system via an input / output control 6009. Volatile RAM 3605 is typically implemented as dynamic RAM (DRAM), which requires continuous power to refresh or maintain data in memory. Non-volatile memory 6006 is typically a magnetic hard drive, a magnetic optical drive, an optical drive, or a DVD-RAM or other type of memory system that maintains data after power is removed from the system. Typically, non-volatile memory will also be random access memory, although this is not required.

[0278] While FIG. 60 illustrates the non-volatile memory as a local device directly coupled to the remaining components of the data processing system, the present invention may utilize non-volatile memory that is remote from the system; for example, a network storage device coupled to the data processing system through a network interface, such as a modem or an Ethernet interface. The bus 6002 may include one or more buses connected to each other through various bridges, controllers, and / or adapters, as is known in the art. In one embodiment, the I / O controller 6009 includes a USB (Universal Serial Bus) adapter for controlling USB peripherals. Alternatively, the I / O controller 6009 may include an IEEE-1394 adapter, also known as a FireWire adapter, for controlling FireWire devices.

[0279] Some of the preceding detailed descriptions are presented in terms of algorithms and symbolic representations of operations on data bits within a computer memory. These algorithmic descriptions and representations are the method used by those skilled in the data processing arts to most effectively convey the substance of their work to others skilled in the art. An algorithm is here, and generally, conceived to be a self-consistent sequence of operations leading to a desired result. The operations are those requiring physical manipulations of physical quantities.

[0280] It should be borne in mind, however, that all of these and similar terms are to be associated with the appropriate physical quantities and are merely convenient labels applied to these quantities. As is apparent from the above discussion, unless specifically stated otherwise, throughout this specification and in the following claims, discussions utilizing terms such as those set forth in the appended claims will be understood to refer to the acts and processes of a computer system, or similar electronic computing device, which manipulate and transform data represented as physical (electronic) quantities in the registers and memory of the computer system into other data similarly represented as physical quantities in the memory or registers of the computer system, or other such information storage, transmission, or display device.

[0281] The illustrated techniques may be implemented using code and data stored and executed in one or more electronic devices. Such electronic devices may store and communicate (internally and / or with other electronic devices over a network) code and data using computer-readable media, such as non-transitory computer-readable storage media (e.g., magnetic disks; optical disks; random access memory; read-only memory; flash memory devices; phase-change memory) and transitory computer-readable transmission media (e.g., electrical, optical, acoustical or other forms of propagated signals-carrier waves, infrared signals, digital signals, etc.).

[0282] The processes or methods depicted in the foregoing figures may be performed by processing logic comprised of hardware (e.g., circuitry, dedicated logic, etc.), firmware, software (e.g., embodied on a non-transitory computer-readable medium), or a combination of both. Although the processes or methods are described above with respect to several sequential operations, it should be understood that some of the described operations may be performed in a different order. Additionally, some operations may be performed in parallel rather than sequentially.

[0283] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the medical field. Although specific methods, devices, and materials are described in this application, methods and materials similar or equivalent to those described herein can be used in the practice of the present invention. Although several embodiments of the present invention have been described in detail and with the aid of figures, such figures are for clarity of understanding only and are not intended to be limiting. Various terms have been used herein to convey an understanding of the present invention, but it will be understood that the meaning of these various terms extends to common linguistic or grammatical variations. Furthermore, while some theoretical considerations may have been advanced to provide an understanding of the present technology, the appended claims of the present invention are not bound by such theories. Moreover, any one or more features of any embodiment of the present invention may be combined with any one or more other features of any other embodiment of the present invention without departing from the scope of the present invention. It is still further understood that the present invention is not limited to the embodiments described for illustrative purposes, but is defined only by a fair reading of the claims appended to the patent application, including the full scope of equivalence to which each element is entitled.

[0284] Some embodiments of the sensing Foley catheter system include sterilizing the urine collection chamber itself or other components of the system using ultraviolet light, or light of an appropriate wavelength. The ultraviolet light source may shine ultraviolet light directly through the wall of the urine collection chamber, or alternatively, the ultraviolet light source may be located inside the urine collection chamber. The ultraviolet light source may be used to sterilize the urine collection chamber when the chamber is empty, full, or partially full. The ultraviolet light source may be used to sterilize the urine as it enters the urine collection chamber. The ultraviolet sterilization process may be continuous or intermittent. The ultraviolet light source may be located anywhere within the sensing Foley catheter system. Ultraviolet light, or other wavelengths of light, may be used within the bladder.

[0285] Spectroscopy - Spectrophotometry

[0286] Some embodiments of the sensing Foley catheter system include using light wavelengths ranging from about 520 nm to about 650 nm to distinguish between bacteria, red blood cells, and / or plasma / white blood cells. See the area inside the oval in FIG. 61.

[0287] Some embodiments of the sensing Foley catheter system include combining spectrophotometry to identify white blood cells and bacteria in combination with identifying a decrease in pO2 and / or an increase in CO2 to identify infection.

[0288] In some embodiments of the sensing Foley catheter system, the controller includes filtering the urine volume data to compensate for increased urine volume immediately following administration of a diuretic. Generally, urine volume increases immediately following administration of a diuretic. However, in certain circumstances, it is beneficial to essentially ignore data of increased urine volume associated with administration of a diuretic. The controller of the sensing Foley catheter system can automatically ignore urine volume data associated with administration of a diuretic by identifying the shape of the urine volume curve associated with administration of a diuretic and subtracting and / or ignoring data associated with this increase. Identification of the shape of the curve may be by slope, length of increase, amplitude of increase, shape, etc. Subtraction of diuretic-induced urine volume data may be beneficial in determining or predicting the onset of AKI. See FIG. 62. For example, if urine volume rises above about 2000 mL / hr (peak), the controller may recognize that this is a situation in which a diuretic has been administered.

[0289] The increase in urine volume due to administration of a diuretic can be distinguished from the increase in urine volume due to clamping or other obstruction of the urinary drainage tube and / or Foley catheter. In a situation where the drainage lumen is clamped, the urine volume before the increase will be substantially zero or very low, e.g., less than 5 ml / hour. In contrast, in a situation where a diuretic is administered, the urine volume immediately before administration of the diuretic may be very low, but will likely be greater than zero, e.g., greater than about 5 ml / hour. In addition, in a situation where the drainage lumen is clamped, the increase in urine volume after the drainage lumen is unclamped will be relatively short, e.g., about 30 seconds to about 5 minutes. In contrast, in a situation where a diuretic is administered, the increase in urine volume will be longer, e.g., about 30 minutes to about 2 hours. In addition, in a situation where the drainage lumen is clamped, the urine volume after the drainage lumen is unclamped will likely be less than about 1000 mL. Conversely, in a situation where a diuretic has been administered, the urine volume following administration of the diuretic would likely be greater than about 1000 ml. Any or all of these factors may be used by the controller to analyze the urine output over time curve to determine when a diuretic has been administered and to subtract the increased urine output due to the diuretic from the urine volume presented to the user.

[0290] In this manner, the controller may automatically determine when to administer a diuretic. Alternatively, the user interface of the controller may include a button or other user input device (e.g., touch screen, voice control, etc.) to indicate that a diuretic has been administered. The controller will then look for increased urine volume and subtract the increased urine volume due to the diuretic from the urine volume data presented to the user.

[0291] Some embodiments of the sensing Foley catheter system include a controller that determines abdominal perfusion pressure (APP). APP is defined as the difference between mean arterial pressure and intraperitoneal pressure (IAP). Mean arterial pressure can be determined in a conventional manner and combined with the controller's determination of IAP to determine APP. The controller is further capable of automatically altering infusion of fluids and / or pressor / vasopressor to increase or decrease blood pressure.

[0292] Prevents filters / vents from getting wet

[0293] Some embodiments of the sensing Foley catheter system include one or more vents and / or filters to prevent negative pressure from building up in the Foley catheter and causing aspiration trauma to the bladder. Filters / vents may also be located at the junction of the Foley catheter and the drainage tube or elsewhere, such as in the urine collection receptacle or within the lumen of the drainage tube or Foley catheter itself, as described below.

[0294] The filter / vent in some embodiments is configured to repel fluids, i.e., from hydrophobic materials. However, despite the use of hydrophobic materials, the filter / vent is susceptible to wetting by fluids, especially urine. In some embodiments, the filter / vent includes a larger lumen, i.e., lumen area, in which the filter / vent is located to reduce the possibility of fluid 6302 filling the lumen due to surface tension of the fluid. FIG. 63A shows a small diameter lumen, while FIG. 63B shows a larger diameter lumen in the vent / filter area. Note that if the vent / filter 6304 is facing up or outward, a smaller lumen may still wet the filter / vent with fluid 6202, while a larger lumen may reduce the possibility of wetting the filter / vent.

[0295] In embodiments where the filter / vent is located at or near the junction of the Foley catheter and the drainage tubing, the area under or near the filter / vent may be taped to the patient's leg to stabilize the Foley catheter once it is in place. The larger lumen tubing helps prevent wetting of the filter / vent in such situations, especially if the vent / filter is oriented away from the leg and thus away from the patient. In some embodiments, the vent barb may be configured such that the vent / filter faces outward when the barb or barb area is taped to the patient's leg. For example, the barb may be curved or attached to a curved base to better attach and orient to the patient's leg 6402 as shown in FIG.

[0296] In some embodiments, the barb area may be elongated, for example between 6 inches and 12 inches, so that the vent / filter can be easily positioned in a location and manner that keeps the vent / filter from getting wet while being positioned further away from the patient.

[0297] In some embodiments, the vent / filter may be located at multiple points around the diameter of the drainage lumen or at other points within the barb. Alternatively, the vent may surround all or most of the circumference of the lumen. In these embodiments, a reinforcing cuff or other structure may surround the vent to provide structural integrity to the lumen. The filter / vent may be located along the length of the drainage tube.

[0298] The embodiment shown in Fig. 65 will also prevent wetting of the vent / filter. This embodiment includes a vent tube 6502 having an inner lumen that connects to a drainage lumen 6504 near the barb area 6506 and is vented to atmosphere or other air / gas / fluids via one or more filters / vents 6508 along the vent tube and / or near the other end. The filters / vents may be within the urine collection receptacle as shown in Fig. 65 or may be located elsewhere, such as separate from the urine collection receptacle.

[0299] The vent lumen may be incorporated alongside or within the urinary drainage lumen. The vent lumen may alternatively be separate from the drainage tube lumen and connected to the drainage tube lumen, for example, at the vent tube / drainage tube junction near the barb region 6506.

[0300] The embodiment depicted in Figure 66 shows a sensing Foley catheter system comprising a positive pressure vent tube 6602 having an inner lumen in fluid communication with a urinary drainage lumen 6604 and a pump 6606. The positive pressure vent tube may include a filter 6612 anywhere along its length, in-line or otherwise. The positive pressure vent tube may include a vent at either end of the tube, may include a vent anywhere along the tube, or may include multiple vents.

[0301] Instead of pulling negative pressure into the urinary drainage lumen and pumping positive pressure to atmosphere, the pump returns positive pressure to the urinary drainage lumen through the positive pressure tube. Alternatively, different pumps may be used for negative and positive pressure. In this manner, a precise negative or positive pressure may be controlled at the junction 6608 between the urinary drainage lumen and the positive pressure vent tube. Preferably, the pressure in the junction 6608 is slightly negative or neutral to prevent backflow of fluid into the Foley catheter. For example, the pressure in the junction may be maintained at approximately 0 mmHg. Alternatively, the pressure in the junction may be maintained at approximately -2 mmHg. An optional regulator 6610 may control the negative pressure relative to the positive pressure by magnitude, timing, etc. For example, the regulator (controlled by the control unit) may implement a slight delay so that negative pressure is first pulled on the urinary drainage line and then, at a set time or when a certain negative pressure is achieved, positive pressure is applied to the positive pressure tube to complete the positive pressure tube / drainage tube junction. This allows the net pressure at the positive pressure tube / drainage tube junction to be positive, preventing urine from flowing into the bladder instead of out of it. An optional regulator may be in the form of a vent with specific dimensions (lower surface area or denser filter material for higher resistance, larger surface area or looser filter material for lower resistance). The positive pressure vent tube may be connected to the urinary drainage lumen through a valve, such as an umbrella valve, that has a set crack pressure.

[0302] Alternatively, the positive pressure tube may be pressurized with compressed sterile fluid / gas / air.

[0303] In addition, the normal filling and emptying of the bladder may be duplicated by precisely controlling the negative pressure acting on the bladder. For example, a neutral or zero pressure may be maintained or a slight positive pressure may be maintained at the base of the Foley for a period of time to allow the bladder to fill normally. Then, after a set time has elapsed or after a predetermined pressure (i.e., the pressure required to maintain neutral pressure at the base of the Foley catheter) has been reached, the pressure may be reduced to allow the bladder to empty or empty. This process may be controlled by a controller that controls the pressure regulator to repeat the process to emulate the normal filling and emptying of the bladder.

[0304] In some embodiments, a valve may be used at the base of the Foley catheter to better control the pressure in that area, including the pressure (negative or positive) exerted on the bladder.

[0305] It is noted that the positive pressure tube embodiments may be used in combination with any of the sensing Foley catheter system embodiments, including those having different filter / vent structures than those shown herein. In addition, any of the anti-airlock embodiments may be used in combination with regular, i.e., non-sensing, Foley catheters, or other catheters or drainage tubes.

[0306] 67-86 are expanded views of barb region X of FIG. 66 to show examples of different embodiments of this region.

[0307] In the embodiment shown in FIG. 67, a valve 6702, such as an umbrella valve with a set crack pressure, is shown between the lumen of the positive pressure vent tube 6602 and the urinary drainage lumen 6604. The valve may be a one-way valve. A vent 6704 is shown between the positive pressure vent tube and atmosphere. There are also configurations where only a vent or only a valve is present. An opening 6706 is in fluid communication with the urinary drainage lumen 6604 and a chamber 6714 (with the valve 6702 periodically blocking fluid communication to the chamber). The chamber 6714 is in fluid communication with the lumen of the positive pressure vent tube 6602. Periodically or continuously, positive pressure is applied via the positive pressure lumen 6602 and / or negative pressure is applied to the urinary drainage lumen 6604. When the crack pressure of the valve 6702 is exceeded, fluid, preferably gas, flows through the valve 6702, through the opening 6706, and through the lumen of the urinary drainage lumen 6604. This serves both to clear the line of an airlock or any blockages, and to clear the chamber 6714 of any fluid, thereby reducing the chance of the vent 6704 becoming wet. It also helps to clear the vent 6704 if it does get wet. The crack pressure of the valve 6702 is the pressure difference between the positive pressure lumen 6602 and the urinary drainage lumen 6604. When the pressure in the urinary drainage lumen falls below the pressure in the positive pressure lumen by the crack pressure, the valve opens, allowing fluid to flow from the positive pressure lumen, through the chamber, through the opening 6706, and through the drainage lumen. For example, the crack pressure may be less than about 1 mmHg. Alternatively, the crack pressure may be less than about 2 mmHg. Alternatively, the crack pressure may be less than about 3 mmHg.Alternatively, the crack pressure may be less than about 4 mmHg.Alternatively, the crack pressure may be less than about 5 mmHg.Alternatively, the crack pressure may be less than about 10 mmHg.

[0308] The pressure in the urinary drainage lumen may be periodically or continuously about -5 mmHg. Alternatively, the pressure in the urinary drainage lumen may be periodically or continuously about -7 mmHg. Alternatively, the pressure in the urinary drainage lumen may be periodically or continuously about -10 mmHg. Alternatively, the pressure in the urinary drainage lumen may be periodically or continuously about -15 mmHg. Alternatively, the pressure in the urinary drainage lumen may be periodically or continuously about -20 mmHg. Alternatively, the pressure in the urinary drainage lumen may be periodically or continuously about -25 mmHg. Alternatively, the pressure in the urinary drainage lumen may be periodically or continuously about -30 mmHg.

[0309] The positive pressure in the positive pressure lumen may be about 5 mmHg periodically or continuously. Alternatively, the positive pressure in the positive pressure lumen may be about 7 mmHg periodically or continuously. Alternatively, the positive pressure in the positive pressure lumen may be about 10 mmHg periodically or continuously. Alternatively, the positive pressure in the positive pressure lumen may be about 15 mmHg periodically or continuously. Alternatively, the positive pressure in the positive pressure lumen may be about 20 mmHg periodically or continuously. Alternatively, the positive pressure in the positive pressure lumen may be about 25 mmHg periodically or continuously. Alternatively, the positive pressure in the positive pressure lumen may be about 30 mmHg periodically or continuously.

[0310] Vents may also or alternatively be present at other points along the positive pressure vent tube, such as near a pump or as part of a pressure regulator. A second vent / valve assembly 6708 is shown at the barb in FIG. 67, but this second vent / valve assembly may or may not be present. An optional thermistor 6710 and optional pressure lumen 6712 are also shown. The positive pressure vent tube may alternatively be exposed to atmospheric pressure. Valves or additional valves may be present anywhere in the system, including in the positive pressure tube 6602 or in the reservoir.

[0311] FIG. 68 illustrates a vent 6802, a valve 6804, and a barb region including a small cross-sectional area 6806 according to one embodiment, where the cross-sectional area is large enough to allow free flow of air / gas from the vent to the urinary drainage lumen, but small enough to prevent the flow of liquids into the vent. For example, the constriction 6806 may be less than about 1 mm in diameter. Alternatively, the constriction may be less than about 2 mm in diameter. Alternatively, the constriction may be less than about 3 mm in diameter. Alternatively, the constriction may be less than about 4 mm in diameter. The length of the constriction may be about 1-5 mm. Alternatively, the length of the constriction may be about 5-30 mm. The embodiment illustrated in FIG. 68 may or may not include a positive pressure tube, although the drawings are shown without the positive pressure tube (i.e., exposed to atmosphere). This embodiment may or may not include a valve. This and any of the embodiments may be incorporated into the barb or may be separate components that can be added to the barb (via a sampling or other port) or elsewhere in the system (e.g., along the drainage tube, preferably in the 1 / 3 of the drainage tube closest to the patient).

[0312] FIG. 69 illustrates a barb region according to one embodiment including a vent 6902 and a vent tube 6904 of sufficient length to allow free flow of air / gas from the vent to the urinary drainage lumen, but prevent liquid flow into the vent. For example, the vent tube portion 6904 may be about 1-10 mm in diameter and about 1-10 cm in length. For example, the vent tube portion 6904 may be greater than about 2 cm in length. Alternatively, the vent tube portion 6904 may be greater than about 4 cm in length. Alternatively, the vent tube portion 6904 may be greater than about 10 cm in length. The embodiment illustrated in FIG. 69 may or may not include a positive pressure tube, but is shown here without the positive pressure tube. This embodiment may or may not include a valve.

[0313] FIG. 70 illustrates a barb region according to one embodiment including a vent 7002 and an elongated serpentine vent tube 7004 that allows free flow of air / gas from the vent to the urinary drainage lumen, but is sufficiently serpentine to prevent liquid flow into the vent. For example, the vent tube portion 7004 may be a coil. The embodiment shown in FIG. 70 may or may not include a positive pressure tube, but is shown here without a positive pressure tube. This embodiment may or may not include a valve.

[0314] FIG. 71 illustrates a barb region according to one embodiment that includes a vent 7102 and a small vent tube 7104 that is sufficiently serpentine to allow free flow of air / gas from the vent to the urinary drainage lumen but prevent liquid flow into the vent. For example, the vent tube portion 7104 may be a tube with a baffle, or mesh, on the inner lumen. The embodiment shown in FIG. 71 may or may not include a positive pressure tube, but is shown here without one. This embodiment may or may not include a valve.

[0315] FIG. 72 illustrates a barbed region according to one embodiment including a vent 7202 and a vent tube 7204. In this embodiment, the vent tube is in fluid communication with the positive pressure tube 7206, and the vent 7202 is aligned with the positive pressure lumen such that fluid under positive pressure passes through / across the vent and into the drainage lumen via opening 7208. Here, the vent tube 7204 is shown coiled to help prevent urine backflow into the vent tube, but the vent tube 7204 may be of any configuration including a straight tube or a lumen incorporated into the barbed region. The vent 7202 is shown here near the junction of the vent tube 7204 and the positive pressure tube 7206, but the vent may be located anywhere along the positive pressure lumen, including near the pump / cassette, or near the opening to the drainage lumen 7208. This embodiment may or may not include a valve.

[0316] 73A and 73B show a barbed region according to one embodiment including a vent 7302 and a small vent tube 7304 that allows free flow of air / gas from the vent to the urinary drainage lumen, but has enough tortuosity to prevent liquid flow to the vent. Additionally, the vent end of the vent tube 7304 may be configurable, bendable, or deformable so that it can be oriented upward after the barbed region is secured to the patient's leg. Having the vent end of the vent tube facing upward reduces the chance of the vent being exposed to liquid. For example, the vent tube portion 7304 may be a substantially flattened coil. The embodiment shown in FIG. 73 may or may not include a positive pressure tube, but is shown here without the positive pressure tube. This embodiment may or may not include a valve 7306.

[0317] FIG. 74 illustrates a barb area according to one embodiment including multiple vents 7402 and optional valve 7404. Having multiple vents reduces the chances that all of the vents will be wet with urine. The multiple vents may be in any suitable configuration including lines, circles, etc. The multiple vents may be on one side of the barb or may partially or completely surround the barb. For example, two vents may be included, three vents may be included, four vents may be included, five vents may be included, six vents may be included, seven vents may be included, eight vents may be included, nine vents may be included, or ten vents may be included. The embodiment shown in FIG. 74 may or may not include a positive pressure tube, but is shown without the positive pressure tube in the drawings. This embodiment may or may not include a valve.

[0318] FIG. 75A illustrates a barb region according to an embodiment that does not rely on vents, although it may still include one or more vents. In this embodiment, the positive pressure tube 7502 is in fluid communication with the urinary drainage lumen via opening 7504. Additionally, a valve, preferably a pressure sensitive valve 7506, is between opening 7504 and the drainage catheter and is in fluid communication with a positive pressure source via opening 7510. The valve 7506 is depicted in FIG. 75A as an inflatable valve, such as an annular balloon (also shown in FIG. 75B). The valve 7506 may be inflated via the same pressure source connected to the positive pressure tube 7502 or via a separate pressure source. The valve 7506 may be in fluid communication with the lumen of the positive pressure tube 7502 as shown here, or may be inflated via a separate positive pressure lumen.

[0319] In this embodiment, valve 7506 closes when positive pressure is cyclically applied to the drainage lumen via positive pressure tube 7502. Closing the valve prevents air or positive pressure from reaching the bladder and also allows positively pressurized fluid (gas or liquid) to purge the drainage lumen. When the positive pressure in the positive pressure tube is reduced, the valve opens and urine again drains from the bladder. A slight positive pressure may be maintained in the positive pressure tube to counteract the negative pressure in the urinary drainage line. If more pressure is needed to clear the line of the airlock, valve 7506 is closed during the higher pressure flush.

[0320] Figure 76 shows an embodiment similar to that shown in Figure 75, but in this embodiment, valve 7602 is a passive mechanical valve. Valve 7602 is normally in a flat or open position. If the positive pressure in the positive pressure tube is higher than any negative pressure in the drainage lumen, the valve will automatically close to prevent fluid / positive pressure from being transferred to the patient's Foley catheter / bladder.

[0321] Alternatively, a venturi may be used to control the negative and positive pressures seeping into the barb area, similar to an automobile carburetor.

[0322] 77A and 77B show another embodiment that uses a more active valve system. This embodiment includes a suction chamber 7702, a compliant portion 7704, a patient-side valve 7706, a drainage-side valve 7708, a drainage lumen inlet 7710, and pressure lines 7712, 7714, 7716, 7718.

[0323] In the passive or open position, both the patient side valve 7706 and the drainage side valve 7708 are open, i.e., the balloon / bladder is not inflated, allowing urine to pass freely from the drainage catheter 7722, through the drainage lumen 7720 of the barb, and through the drainage tube 7724. In the open position, the compliant portion 7704 is in a neutral position. In the event of an occlusion event such as an airlock, or periodically to prevent occlusion, the drainage side valve 7708 is closed by applying pressure, such as a pressurized fluid (gas or liquid) via pressure line 7716. The compliant portion 7704 is inflated by applying negative pressure via pressure line 7718. The pressure line 7714 remains neutral or closed. The pressure line 7712 remains neutral, closed, or negative to pull the valve 7706 all the way down. In this configuration, the compliant portion 7704 can be expanded to effectively apply negative pressure to the drainage catheter while blocking fluid flow to the drainage line 7724. This configuration is shown in Figure 77A.

[0324] In the configuration of Fig. 77A, the pressure drop lasts for a short period of time, for example, about 0.5 to 1 second, or about 1 to 3 seconds, or about 3 to 5 seconds. The patient valve 7706 is then closed by applying a positive pressure to the pressure line 7712, and the drainage valve is opened by reducing the pressure in the pressure line 7716 to neutral or applying a negative pressure to the pressure line 7716. The volume of the compliant portion 7704 is reduced by increasing the pressure in the pressure line 7718 to neutral or applying a positive pressure to the pressure line 7718. A positive pressure may also be applied to the pressure line 7714. This configuration is shown in Fig. 77B. In this configuration, the fluid in the drain lumen 7720 and drainage line 7724 can be flushed with fluid (gas / liquid) by positive pressure applied via pressure line 7714 and / or by the reduced volume of the conformable portion 7704, effectively flushing urine through the drainage line. After flushing, the system is returned to the neutral position with both the patient-side valve 7706 and the drainage-side valve 7708 open and the conformable portion 7704 in the neutral position.

[0325] FIG. 78 shows an embodiment similar to that shown in FIG. 72, but with a positive pressure vent tube 7802 rather than a separate vent tube. A vent 7804 is in fluid communication with and aligned to the lumen of the positive pressure vent tube 7802. The vent 7804 is also in fluid communication with the barb region of the urinary drainage lumen 7808 and is connected to the region 7808 by an opening 7806. Fluid / air / gas under positive pressure is passed across the vent 7804, through the opening 7806, and into the region 7808 which is in fluid communication with the drainage lumen. That is, the positive pressure fluid / air / gas passes across the filter to the interior of the barb. Wetting of the vent 7804 is prevented by controlling the positive pressure in the positive pressure tube and across the vent 7804, as well as the negative pressure of the drainage lumen. In some embodiments, the pressure in the barb area of ​​the urinary drainage lumen 7808 is close to about zero. The vent 7804 may be anywhere along the length of the positive pressure vent tube 7802. The embodiment shown in FIG. 78 may or may not include a one-way valve between the filter and the opening. Positive pressure fluid / air / gas may pass through the vent continuously, intermittently, sporadically, etc. Positive pressure fluid / air / gas may pass through the vent as a stream or as puffs or pulses.

[0326] Filters throughout the system may be cleaned using pressure, whether at the barb, positive pressure tube, vent tube, reservoir, or elsewhere. For example, a puff of pressurized air or gas may be used across the filter to clean the filter if it is wet or to prevent the filter from wetting. Alternatively, a steady or intermittent flow of air or gas may be used.

[0327] FIG. 79 illustrates an embodiment in which the area in the barb that is in fluid communication with the urinary drainage lumen has a larger volume. Fluid 7902, such as urine, flows from the drainage catheter into a large reservoir 7904, which then flows into the urinary drainage lumen. The reservoir 7904 is large enough that it is unlikely to be completely filled with liquid. The volume of the reservoir that is not filled with liquid will fill with air or gas. A one-way valve 7908 may also be present. Since the reservoir 7904 will always have some air / gas in it, the vent 7906 may be positioned so that it rarely comes into contact with the urine / fluid in the reservoir. That is, the vent may be on the side of the air bubbles in the reservoir. Two or more vents may be provided to ensure that at least one vent is always in fluid communication with the gas bubbles in the reservoir. In some embodiments, the volume of the reservoir 7904 may be larger than the volume of the lumen of the drainage tube.

[0328] 80A and 80B show an embodiment in which the vent area is very large. The vent 8002 is shown here to be a large flat circle or disk, but the vent may be any shape and size. The vent may be flat or may be curved, wrapping around the barb area. In the embodiment shown, one opening 8004 and one-way valve 8006 are shown, but other embodiments may have two or more openings, and may or may not have a valve. In some embodiments, the vent may be approximately 1 cm. 2 In some embodiments, the filter surface may be greater than about 2 cm. 2 In some embodiments, the filter surface may be greater than about 3 cm to about 4 cm. 2 Alternatively, in some embodiments, the filter surface is about 2 to about 4 cm 2 Alternatively, in some embodiments, the filter surface is about 4 to about 6 cm 2 Alternatively, in some embodiments, the filter surface is about 6 to about 10 cm 2 It is.

[0329] FIG. 81 illustrates an embodiment having a replaceable vent. The replaceable vent 8102 is shown here in an embodiment having a positive pressure tube 8104 and a one-way valve 8106, however, there may be embodiments without the positive pressure tube and / or valve. The replaceable vent 8102 may be removed and replaced via an attachment mechanism such as a luer lock, snap lock, slide-in lock, press fit, or any other suitable mechanism. Replacement of the vent may be done periodically, such as once a day, or as needed, such as when the control alerts the user that the vent is no longer functioning properly, or when the user notices that the vent has not functioned for a long time. The vent may contain urine-sensitive chemicals or components of urine that change color to indicate that it is wet. For example, pH-sensitive paper, or other chemical or attribute-sensitive paper, may be used for a replaceable vent that changes color to be visible to the user. The replaceable vent may be disposable.

[0330] 82A and 82B show an embodiment in which the filter is flexible. In this embodiment, the filter 8202 may be flexible or deformable, i.e., concave / convex, or loose in its housing, and the movement of the flexible filter 8202 may help to unclog the filter if it is wet or contaminated. The movement of the filter may be controlled by positive pressure via the positive pressure tube 8204, negative pressure via the urinary drainage lumen, negative pressure via the valve 8206, or any single or combination of these. Some embodiments may further include a mechanical mechanism for agitating, shaking, vibrating, flexing, and / or moving the filter 8202. FIG. 82A shows an example of an embodiment in which the filter is concave due to, for example, negative pressure in the urinary drainage lumen. FIG. 82B shows a similar example after positive pressure is applied to the vent via the positive pressure tube 8204. The pressure in the vent housing 8208 may be controlled by the crack pressure of a one-way valve, or by the relative negative and positive pressures in the urinary drainage lumen and in the positive pressure tube. In a similar embodiment, there may be cases where the filter is not flexible, but the pressure is controlled in the vent housing 8208 in a similar manner that keeps the filter dry.

[0331] Alternatively, the filter (flexible or otherwise) may be mechanically wiped or scrubbed, either manually or automatically. Alternatively, the filter may contain chemicals, such as enzymatic cleaners, that inhibit protein adhesion and / or accumulation. Alternatively, the filter may contain agents that inhibit biofilms, such as antibacterial agents.

[0332] FIG. 83 illustrates an embodiment with multiple stacked filters. Filters of different pore sizes may be stacked and used. For example, a coarse pore filter 8304 may protect the fine pore filter 8302 from getting wet. The coarse pore filter 8304 may be placed between the fluid / urine and the fine pore filter 8302. In this configuration, the fluid / urine must pass through the coarse filter 8304 to contact the fine filter 8302. More than two filters may be stacked in this manner, and either graduated pore sizes, or similar pore sizes, or any pore size may be used. For example, finer pore filters may be stacked further away from the urine / liquid. Alternatively, one or more coarse pore filters of the same or different pore sizes may be placed between the urine / liquid and the fine pore filter. There may or may not be a one-way valve. The pore size of the coarse pore filter 8304 may be about 10 micrometers. Alternatively, the pore size of the coarse pore filter 8304 can be from about 10 to about 20 micrometers. Alternatively, the pore size of the coarse pore filter 8304 can be from about 10 to about 30 micrometers.

[0333] FIG. 84 illustrates an embodiment in which a continuous positive pressure is exerted on the barb area by the fluid in the positive pressure tube 8402. The positive pressure tube is under a substantially constant positive pressure such that fluid (preferably air / gas) is continually passing through the opening 8404. The positive pressure exerted on the fluid in the interior 8406 of the barb is controlled so that the fluid does not backflow into the urinary drainage catheter. That is, the negative pressure exerted on the fluid in the interior 8406 is always greater than or approximately equal to the positive pressure exerted on the fluid in the interior 8406. The positive pressure may be controlled with a controller and / or may be controlled by the size of the opening 8404, for example, by sizing the opening 8404 very small. For example, the diameter of the opening 8404 may be less than about 1 mm. Alternatively, the diameter of the opening 8404 may be less than about 2 mm. Alternatively, the diameter of the opening 8404 may be less than about 3 mm. Alternatively, the diameter of the opening 8404 may be less than about 4 mm.

[0334] FIG. 85 illustrates an embodiment having an accordion shaped vent. The vent 8502 in this embodiment is shaped like an accordion. The vent may be compressed in the direction of the double headed arrow. This compression may clear any blockages / wetness in the vent. Compression may be done manually, automatically / mechanically, and / or using pressure (negative and / or positive) within the vent area.

[0335] FIG. 86 illustrates an embodiment with a single vent and multiple openings. In this embodiment, two or more small openings 8602 separate the urinary drainage lumen from the vent 8604. The small openings prevent fluids from contacting the vent 8604. The multiple openings may act as redundancy, so if one or more openings become clogged, the others remain open. The openings may also be used to control the passage of air / gas / fluids through the vent 8604 - the more holes, the less resistance to air flow, and the fewer holes, the more resistance to air flow.

[0336] Any of the embodiments herein may include a physiological pressure measurement or may be used without a physiological pressure measurement. For example, the system shown in Figures 67-86 and other embodiments does not include a thermistor or a pressure lumen and can be used in combination with a standard Foley catheter.

[0337] In some embodiments, pressure may be measured at the positive pressure tube / drainage tube junction. Alternatively, pressure may be measured at the sensing Foley catheter / drainage tube junction, or at the area of ​​the barb. Pressure may be measured at any of these locations by incorporating an additional tube or lumen in fluid communication with the pressure tube / drainage tube junction, or in fluid communication with the area of ​​the barb at one end and in fluid communication with a pressure sensor or transducer at the other end. For example, this pressure measurement lumen may be in fluid communication with a control unit housing a pressure sensor at one end (sensor side) and in fluid communication with the positive pressure tube / drainage tube junction at the other end (sensing side). There may be a pressure sensitive membrane at the sensing end to prevent urine contamination of the lumen.

[0338] Airlocks may also be detected so that they may be optimally eliminated and / or avoided. Using any of the embodiments herein, the controller may apply a slight positive or negative pressure to the urinary drainage lumen and detect the response. Because air is more compressible than urine, a dampened response may indicate the presence of an airlock, and an undamped response may indicate less airlock. If excessive airlocks are detected, the controller may initiate the elimination of the airlock, for example, by applying negative pressure to the drainage lumen.

[0339] In some embodiments, the valve can be anywhere in the system, including in the positive pressure tubing or in the reservoir.

[0340] The vent tube may be a separate tube from the drainage tube and may be inserted into the drainage lumen or into the Foley catheter. FIG. 87 illustrates a sensing Foley catheter system according to an embodiment in which the vent tube is in the urinary drainage tube. This type of embodiment has the advantage that any standard drainage tube can be used. The vent tube essentially places a vent anywhere in the drainage lumen, either in the drainage tube or in the Foley catheter. The vent tube may be slidably inserted inside the drainage tube and / or Foley catheter and can be moved at any time.

[0341] In the embodiment shown in FIG. 87, the vent tube 8704 may open at one end ("air end" 8708) to a vent / filter 8702 in the urine collection reservoir (open to atmospheric pressure) and at the other end ("urine end" 8710) to be within the urinary drainage lumen 8706. Here, the vent tube is shown terminating within a barb at the base of the Foley catheter, but the vent tube may terminate anywhere within the urinary drainage lumen, including anywhere within the drainage tube or anywhere within the Foley catheter. The vent tube may remain in one location or may be moved within the system to maximize urinary drainage and minimize airlock and bladder damage due to negative pressure within the bladder.

[0342] FIG. 88 illustrates a sensing Foley catheter system according to another embodiment in which a vent tube 8802 has a vent / filter 8804 at the "urine end" of the tube and is open to atmosphere at the "air end" 8806 of the tube. Also, a filter / vent may be provided at both ends. The "air end" of the vent tube may exit the drainage lumen via a Y-arm adapter, stopcock, or other standard method. The "air end" of the vent tube may exit the system from within the urine collection container via a channel or port built into the urine collection container. Again, the vent tube may be used in conjunction with any urine drainage tube, including standard urine drainage tubes.

[0343] FIG. 89 illustrates an embodiment similar to that shown in FIG. 88 with the addition of a positive pressure tube 8902.

[0344] 90, 91A, and 91B are diagrams illustrating a vent tube in different locations within a sensing Foley catheter system. In FIG. 90, the "urinary end" 9002 of the vent tube is only partially within the drainage tube. For example, the vent tube may be inserted through about one-half of the drainage tube. Alternatively, for example, the vent tube may be inserted through about one-third of the drainage tube. Alternatively, for example, the vent tube may be inserted through about two-thirds of the drainage tube. In FIG. 91A, the "urinary end" 9002 of the vent tube is within the Foley catheter. The location of the "urinary end" of the vent tube is determined based on maximizing urinary drainage, minimizing the effect of airlock on urinary drainage, and minimizing negative pressure in the bladder. In Figure 91B, the vent tube is inside the drainage tube and is connected at one end at or near the barb, terminating approximately 6 to 24 inches below the drainage line. The vent tube may or may not include a filter or valve.

[0345] In some embodiments, the vent tube is attached to a sensing Foley catheter system after an initial amount of urine has been drained from the bladder.

[0346] The vent tube may incorporate one or more filters / vents. The vent tube may incorporate one or more cutouts in fluid communication with the inner lumen of the vent tube and ultimately in fluid communication with a vent / filter in the urine collection reservoir or elsewhere. Multiple filters / vents or multiple cutouts may be around the periphery of the vent tube, or along the vent tube, or both. The vent tube may include ultraviolet light directed at the filter, the "urine end," or elsewhere to maintain sterility.

[0347] 91C and 91D show other embodiments where the vent tube is concentric with the urinary drainage lumen. The embodiment shown in FIG. 91C may be similar to the vent and drainage tubes shown in FIG. 87, where the vent tube 8704 is within the drainage lumen 8706. The embodiment shown in FIG. 91D shows an embodiment where the drainage lumen 8706 is within the vent lumen 8704. The vent lumen in any of the embodiments disclosed herein may extend the length of part or the entirety of the drainage lumen.

[0348] The various lumens of the system may be joined to one or more tubular extrusions. The tubes may also be separate, or two or more may be attached to each other to prevent kinking. For example, four tubes may be attached to each other along a substantial portion of their length, including lumens for drainage, venting, temperature and pressure measurement. Alternatively, five tubes may be connected. Tubes may be included for added rigidity. The lumens of the tubes may include reinforcing wires or mandrels for added rigidity. The tubes may be co-extruded or extruded separately and then connected along their length. The lumens may be connected along all or part of their length. For example, the urinary drainage tube, and optionally the vent tube, may be separated from the temperature and pressure tubes at one or more points along the length of the drainage tube. This allows the urinary drainage tube (and optionally the vent tube) to be clamped closed without affecting the temperature and pressure functions of the system.

[0349] 92A and 92B show some possible embodiments of a drainage lumen, such as the drainage lumen 1012 shown in FIG. 10A. FIG. 92A shows a drainage lumen with a collapsible / expandable portion 9202. The portion 9202 may be made of a lower durometer material than the rest of the drainage lumen, allowing it to collapse or expand depending on the internal pressure. The lumen will collapse to a lower internal area / volume at low or negative pressure and expand at higher or positive pressure. Airlock is reduced by such changes in lumen volume at different pressures. This type of lumen may be incorporated into any of the embodiments herein.

[0350] FIG. 92B illustrates a drainage lumen including two lumens according to one embodiment. The inner lumen shown here is a negative pressure / urine drainage lumen 9204. The outer lumen is a positive pressure lumen 9206. An opening 9208 is provided between the two lumens. The opening may or may not include a filter membrane. The two lumens may be concentric as shown here or adjacent. The positive pressure lumen serves essentially the same purpose as the positive pressure vent tube shown elsewhere herein. Constant or periodic negative pressure is applied to the drainage lumen 9204, which in turn applies positive pressure to the positive pressure lumen 9206, thereby clearing the drainage lumen 9204.

[0351] 93A-93E show another example of a drainage lumen. This embodiment also includes a drainage lumen 9302 and a positive pressure lumen 9304. In this embodiment, the positive pressure lumen 9304 is expandable and collapsible. In an expanded state of the positive pressure lumen, it partially or completely blocks the drainage lumen. In a collapsed state of the positive pressure lumen, the drainage lumen is substantially open, allowing fluid to flow freely through the drainage lumen. FIG. 93A shows the drainage lumen in an occluded state near the patient end of the drainage tube. FIG. 93B shows the occluded drainage lumen further away from the patient. FIG. 93C shows the drainage lumen in an open state.

[0352] FIG. 93D is a longitudinal view of the drainage tube in a closed state. FIG. 93E is a longitudinal view of the drainage tube in an open state. In the open state, as shown in FIG. 93C and FIG. 93E, the positive pressure lumen 9304 is in a collapsed state and does not substantially obstruct the drainage lumen 9302, allowing urine to flow freely from the body to the reservoir. In the event of an airlock or other obstruction of the drainage tube, the positive pressure lumen is inflated to force urine / liquid down the drainage tube towards the urine collection reservoir. The patient end 9306 of the positive pressure lumen may be of a larger diameter and / or lower durometer than the reservoir end 9308 of the positive pressure lumen. This allows the patient end of the positive pressure lumen to expand before the reservoir end expands. In this manner, the drainage lumen is first occluded at a point closest to the patient, and then expansion of the remaining portion of the positive pressure lumen fills substantially all of the drainage lumen or fills only a portion of the drainage lumen. The positive pressure lumen may be inflated at either the patient end or the reservoir end of the drainage tube. There may be one or more filters along the length of the drainage lumen.

[0353] Embodiments of the sensing Foley catheter system may include the ability to measure pressure within the bladder via a pressure balloon connected to the Foley catheter or via a pressure balloon or other pressure sensor inserted within the drainage tube and / or drainage lumen of the Foley catheter. See, e.g., Figures 94A-94C.

[0354] 94A-94C illustrate an embodiment of a sensing Foley catheter system in which a pressure sensor is in fluid communication with the urinary lumen of the Foley catheter, but may be on a separate catheter. A Foley style catheter 9402 is shown with a urinary lumen 9404 and a urinary drainage opening 9406. A small pressure sensing catheter 9408 having a pressure sensing balloon 9410 is shown within the urinary drainage lumen of the Foley style catheter. The outer diameter of the pressure sensing catheter is small enough to fit within the urinary drainage lumen of the Foley style catheter. For example, the outer diameter of the pressure sensing catheter may be less than about 4 mm, alternatively, the outer diameter of the pressure sensing catheter may be less than about 3 mm, alternatively, the outer diameter of the pressure sensing catheter may be less than about 2 mm, and alternatively, the outer diameter of the pressure sensing catheter may be less than about 1 mm.

[0355] The pressure sensor on the pressure sensing catheter may be near the distal end of the pressure sensing catheter or anywhere along the length of the catheter. The pressure sensor may be a pressure sensing balloon or any type of pressure sensor, such as a piezoelectric sensor, a mechanical sensor, etc. In the case of a pressure sensing balloon, the inflated balloon may be smaller than the inner diameter of the urinary drainage lumen of the Foley catheter, or the inflated balloon may be large enough to fill the urinary drainage lumen of the Foley catheter.

[0356] The inflated pressure sensing balloon can fill the urinary drainage lumen of the Foley catheter, thereby allowing for better pressure measurements. The pressure sensing balloon can be periodically deflated or partially deflated to allow urine to flow from the bladder through the Foley catheter. Control of the inflation cycle of the pressure sensing balloon can be controlled by a controller of the present invention.

[0357] 94B illustrates a pressure sensing catheter according to an embodiment having both an occlusion balloon 9424 and a pressure sensing balloon 9426. Because the occlusion balloon occludes the urinary drainage lumen, the pressure sensing catheter only senses the pressure between the occlusion balloon and the bladder, thereby providing a more accurate measurement of pressure within the bladder.

[0358] The outer diameter of the inflated pressure sensing balloon may be less than about 5 mm, alternatively, the outer diameter of the pressure sensing catheter may be less than about 4 mm, alternatively, the outer diameter of the pressure sensing catheter may be less than about 3 mm, alternatively, the outer diameter of the pressure sensing catheter may be less than about 2 mm, or alternatively, the outer diameter of the pressure sensing catheter may be less than about 1 mm.

[0359] FIG. 94C illustrates a standard Foley-type catheter having a retention balloon 9412, a urinary drainage opening 9406, a retention balloon port 9414, and a urinary drainage port 9416. An adapter 9418 is shown connected to the urinary drainage port 9416. The adapter 9418 has two ports, a urinary drainage port 9420 and a second urinary lumen port 9422. A pressure sensing catheter 9408 is shown in the urinary lumen port 9422. In this manner, the pressure sensing catheter is in fluid communication with the urinary drainage lumen of the Foley-type catheter. The proximal end of the pressure sensing catheter 9408 is connected to a pressure sensor, such as a pressure transducer, as in other embodiments herein. The pressure sensing catheter 9408 may have only a single lumen, which is the sensing balloon lumen, or may include multiple other lumens. Also, when the pressure sensor of the pressure detection catheter is a mechanical pressure sensor, the pressure detection catheter may not have a lumen, or the pressure detection catheter may be provided with a balloon for sealing the urinary drainage lumen of the Foley-type catheter.

[0360] Alternatively, the pressure sensing catheter may be inserted through the urinary drainage lumen of the drainage tube.

[0361] Pressure measurements may be taken over time using a pressure sensing catheter and analyzed in any manner disclosed herein. To improve pressure measurements, the drainage port 9420 may be periodically closed or occluded. Occlusion of the drainage port 9420 may be done mechanically, using a stopcock or valve, or automatically, for example, using a solenoid valve connected to a control unit. An advantage of this embodiment is that the pressure sensing catheter 9408 can be used in combination with any Foley-type catheter to measure pressure. In addition, the pressure sensing catheter 9408 can be inserted and removed from the Foley-type catheter after the Foley-type catheter has already been placed in the patient's bladder.

[0362] The pressure sensing catheter may be combined with vent tubing as shown in the other figures. In this manner, the pressure sensing, urinary drainage, anti-airlock, and vent components of the sensing Foley catheter system may be used in combination with any standard Foley catheter and drainage tubing. Alternatively, the pressure sensing catheter / vent tubing combination may be used in combination with more specialized Foley catheters and / or drainage tubing.

[0363] In any of the embodiments including any type of airlock elimination mechanism, airlock elimination may be performed continuously, periodically (at regular intervals or on demand), on demand, or when an airlock condition is detected. The airlock elimination mechanism prevents or reduces airlocks. For example, the airlock elimination mechanism may reduce airlocks such that an airlock is eliminated at least every 60 minutes. Alternatively, an airlock may be eliminated at least every 45 minutes. Alternatively, an airlock may be eliminated at least every 30 minutes. Alternatively, an airlock may be eliminated at least every 20 minutes. Alternatively, an airlock may be eliminated at least every 10 minutes. Alternatively, an airlock may be eliminated at least every 5 minutes. Alternatively, an airlock may be eliminated at least every minute.

[0364] In any of the embodiments including a vent or filter or vent tube as part of the barb region or drainage tube, the drainage of fluid (i.e. urine) may be discontinuous or interrupted due to gas / air introduced into the drainage lumen via the vent / filter / vent tube, i.e. the drainage lumen may contain alternating liquid (i.e. urine) and gas.

[0365] In any of the embodiments involving measuring urinary output in real time, real time may mean that the reported urinary output measurement is accurate to within about 1 minute. Alternatively, real time may mean that the reported urinary output measurement is accurate to within about 5 minutes. Alternatively, real time may mean that the reported urinary output measurement is accurate to within about 10 minutes. Alternatively, real time may mean that the reported urinary output measurement is accurate to within about 20 minutes. Alternatively, real time may mean that the reported urinary output measurement is accurate to within about 30 minutes. Alternatively, real time may mean that the reported urinary output measurement is accurate to within about 60 minutes.

[0366] Air bubbles in urine - prevent air bubbles from forming and / or affecting the reading

[0367] In some cases, proteins or other components in the urine can cause excessive bubbles in the drainage lumen and / or urine in the urine collection container, which can cause problems such as wetting of the vent / filter(s), urine ingress into the overflow area of ​​the urine collection container, inaccurate measurements, etc. Some embodiments of the sensing Foley catheter system incorporate an anti-bubble mechanism.

[0368] Some embodiments, such as those incorporating positive pressure tubing, provide precise control of pressure within the urinary drainage. A slight positive pressure can be applied occasionally within the drainage system (i.e., the drainage lumen and / or urine collection chamber) to collapse any existing air bubbles or prevent air bubbles from forming.

[0369] A surfactant, such as silicone, simiticon, or other suitable material, may be added to the system. For example, slowly dissolving silicone capsules may be added to the urine collection reservoir. Alternatively, a surfactant coating may be used on the inside of the drainage lumen and / or the inside of the urine collection container.

[0370] Air bubbles may be eliminated or reduced at the junction of the drain tube and the urine collection container. Several embodiments are shown in Figs. 95A-95C. For example, the base of the drainage tube may be S-drain shaped (like a drain under a sink) and the inner diameter of the drainage tube may expand near the junction with the urine collection container or at other points. The drainage tube may be bulb-shaped or cone-shaped. The drain lumen may be annular, as shown in Fig. 95C. In this embodiment, the fluid is forced to flow down the side of the inclined cone surface to reduce air bubbles, similar to how beer is poured down the side of a glass instead of into the center to reduce bubbles. Here, the bubble reduction element is shown at the base of the drainage tube, but it may be anywhere on the drainage tube or anywhere in the system. In some embodiments, the drainage lumen may be flattened to force the urine to contact a surface again. For example, the urinary drainage lumen may be flattened to less than about 1 mm. The urinary drainage lumen may be flattened to less than about 2 mm. The urinary drainage lumen may be flattened to less than about 3 mm.

[0371] Urine may also be forced to flow to a single point, as shown in the inverted cone embodiment of FIG. 96A. The cone may be angled as shown here, or may be more curved. The cone shape generally transitions from small to large and / or large to small regions. Such and other bubble reduction features may also be present in the urine collection reservoir. For example, an angled baffle may be incorporated into the urine collection reservoir to force the fluid to flow down an angled surface, as shown in FIGS. 96B-96D. The angled surface may extend all the way to the bottom of the urine collection reservoir, or may only extend partially into the urine collection reservoir. Different angles may be used, for example angles from about 10 degrees to about 80 degrees.

[0372] Angled baffles, as shown by the embodiment of Figures 96C and 96D, may also be preferred to improve accuracy of urine volume measurements, especially in critical patient conditions where the patient's urine output is low and continuous measurement of urine output (ml / min or ml / sec) is desired to diagnose the patient's vulnerability to the development of AKI, sepsis, or other conditions. To accurately measure small urine volumes, conical or angled baffles are more accurate because the urine column height is greater for a given urine volume compared to flat-bottomed baffles or cassettes. An ultrasonic or similar transducer on the control unit can more reliably measure the height and provide accurate measurements of urine volume and urine output rate, especially when the patient's kidneys are damaged and producing little urine. Additionally, angled baffles or cassettes (urine collection chambers) are less sensitive to changes in the tilt angle of the control unit for small urine volumes compared to cassettes with flat surfaces, reducing measurement error.

[0373] FIG. 97A illustrates a sensing Foley catheter system according to an embodiment in which the drainage lumen extends into the urine collection container / cassette so that fluid is generally discharged below the fluid level into the collected fluid. The drainage end of the drainage lumen 9722 may be cut at an angle so that the tube is not adjacent to the bottom of the cassette where it may obstruct fluid flow. The angled cut 9724 may be about 45 degrees, about 10-80 degrees, or any suitable angle. Other shapes may be used for the drainage end of the drainage lumen to achieve the same results. For example, FIG. 97B illustrates a drainage lumen where the tube of the drainage lumen is splined at the drainage end. The shape of the spline 9726 may be any shape including rounded, rectangular, triangular, scalloped, etc.

[0374] FIG. 97C illustrates a sensing Foley catheter system according to an embodiment in which the drainage lumen extends into the cassette and includes a flattened region 9728. In this embodiment, the cross-sectional area of ​​the drainage lumen may remain the same, or may be increased or decreased at the flattened region, but preferably at least one dimension is increased to force contact with the increased surface area of ​​the fluid flow. As shown in FIG. 97C, the flattened region may direct the flow downward, or the flattened portion may be angled to contact at least one side of the inner surface of the lumen to force the fluid flow. Alternatively or additionally, an angled baffle may be used, such as baffle 9730 shown in FIG. 97D. The angle of baffle 9730 may be about 45 degrees, about 10-80 degrees, or any suitable angle. An angled baffle or flattened region may be used in combination with any of the drainage tube / lumen structures illustrated herein.

[0375] FIG. 98A illustrates an embodiment of a sensing Foley catheter system with increasing and decreasing drainage lumen area. The valve 9832 may be incorporated into the drainage tube above the cassette, as shown in FIG. 98D, may be incorporated into the cassette, or may be incorporated anywhere along the drainage lumen. The areas above and below the bulb may be substantially the same, as shown in FIG. 98B, or alternatively, the area below the bulb may be smaller than the area above the bulb. The reduced drainage lumen area portion 9834 may be relatively short, for example, portion 9834 may be about 1 mm to 10 mm long. Alternatively, portion 9834 may be about 10 mm to 20 mm long. Alternatively, portion 9834 may be about 10 mm long. FIG. 98C illustrates an embodiment in which the stenosis 9836 includes two or more reduced area fluid drainage lumens. This allows for increased surface contact of the drainage tube lumen without significantly reducing the area of ​​the drainage tube lumen. The constriction 9836 may be used in combination with the valve 9832 or without the valve.

[0376] It is noted that any of the bubble reduction embodiments encompassed herein may be used anywhere within the drainage lumen, including drainage tubes outside the cassette, and drainage tubes / lumens within the cassette. For example, Figure 98D shows an embodiment similar to that shown in Figure 98B where the bulb portion is within the cassette.

[0377] FIG. 99A illustrates a sensing Foley catheter system according to an embodiment in which at least a portion of the drainage lumen is rough enough to cause air bubbles to disperse and / or pop.

[0378] 99B and 99C show another air bubble reduction embodiment. In this embodiment, a grid, or honeycomb, or mesh is provided on the inside of the base of the drainage tube. The mesh helps break up air bubbles and may be compressed periodically to clear the area of ​​fluid and also to help break up air bubbles.

[0379] Alternatively or additionally, a flat mesh may be inserted anywhere in the system, for example at the drainage tube / urine collection container junction.

[0380] In some embodiments, the cassette and / or the drainage lumen may be vibrated continuously or intermittently to break up air bubbles.

[0381] 100A-100C show embodiments incorporating a floating or non-floating plate to compress or break up air bubbles at or near the surface of the urine in the urine collection container. The plate may simply float on the surface and passively rise and fall depending on the amount of urine in the container, or the plate may be actively moved up and down. The plate may also be fixed. The plate may be porous or solid. In embodiments where the plate is on the surface of the fluid, the plate may also be used for urine output measurements. The position of the plate may be identified by ultrasound, visual means (such as a camera), laser, or other techniques. The volume of the fluid in the urine collection container may be determined directly from the position of the fluid, which may be determined by the position of the plate.

[0382] The interior of the cassette may be rectangular or other shaped. For example, the interior sides of the cassette may taper inward toward the bottom so that there is a larger urine top surface relative to the volume of urine in the cassette. This may result in more accurate urine volume measurements with smaller urine volumes.

[0383] Some embodiments may include a volumetric baffle at a set volume mark, e.g., 50 mL. This volumetric baffle may be similar to the baffle 2302 shown in FIG. 23, except that it is at a pre-determined volume position. When the top of the urine volume in the cassette is at or near the urine volume baffle, the ultrasound signal will be stronger than otherwise. For example, the volumetric baffle may be positioned such that when the top of the urine volume is about 50 ml (or other set volume), the top of the urine volume will be at or near the volumetric baffle. The ultrasound signal will be strongest when the two surfaces (urine and volumetric baffle) are close to or touching each other.

[0384] Some embodiments may include a waveguide to help account for overturning of the reservoir. For example, the ultrasonic signal may be directed into a cylinder with flat or curved sides to direct the ultrasonic waves to the surface of the fluid in the reservoir where they will reflect back. The waveguide may extend all or part of the way into the reservoir. The waveguide may extend between the ultrasonic transducer / sensor and the surface of the fluid.

[0385] In some embodiments, the ultrasonic transducer / sensor may be flat, and in some embodiments, the surface of the ultrasonic transducer / sensor may be curved, for example, a convex curve, which helps to spread the ultrasonic signal over more angles, which helps to ensure that some of the angles are reflected from the surface of the fluid in the reservoir.

[0386] Some embodiments include a controller that uses an accelerometer to measure the tilt of the reservoir and then uses the angle of tilt to calculate the volume of fluid remaining in the reservoir (i.e., at the low corner of the reservoir) after fluid has been emptied from the reservoir. This calculated volume remaining in the reservoir can be added to the total urine volume calculation to improve accuracy.

[0387] 101A illustrates a sensing Foley catheter system according to one embodiment that includes valves at both the drainage port 10102 and the entry point 10104 where the drainage tube connects to the urine collection container. This allows the controller to periodically pressurize the urine collection container which can reduce air bubbles and / or assist in draining the urine collection container. This entry port valve may also result in a more accurate measurement of urine output since the controller can stop the flow of urine into the urine collection container during emptying.

[0388] 101B illustrates a urine collection container according to an embodiment that provides a longer and / or more convex / tortuous and / or narrower urine overflow path. Such configurations may make it difficult for air bubbles to flow into the overflow path, resulting in inaccurate urine volume measurements. The overflow path may include one or more path angles greater than 45 degrees.

[0389] FIG. 101c illustrates an embodiment of a urine collection container in which the fluid path (indicated by the dashed arrow) between the urine in the reservoir and the cassette pump interface 1148 is convexly elongated to prevent wetting of the interface 1148. The cassette pump interface 1148 may be gas permeable, liquid impermeable, and may include a filter. The fluid path may be about 6-12 cm long. Alternatively, the fluid path may be between about 3-6 cm long. Alternatively, the fluid path may be longer than about 12 cm. Alternatively, the fluid path may be between about 3 cm and about 6 cm long. Alternatively, the fluid path may be longer than about 20 cm.

[0390] 101D illustrates another embodiment of a urine collection container in which the fluid path (shown in dashed lines) between the urine in the reservoir and the cassette pump interface 1148 is convex and elongated to prevent wetting of the interface 1148. The convex path may include coiled or bundled small diameter tubing 10108 as all or part of the fluid path. Preferably, the convex path is convex in three dimensions.

[0391] 101E illustrates another embodiment of a urine collection container in which the fluid path (shown in dashed lines) between the urine in the reservoir and the cassette pump interface 1148 is convexly elongated to prevent wetting of the interface 1148. This embodiment includes both small diameter tubing 10108 and a convex path molded into the cassette. The convex path may be partially molded, partially tubing, all tubing, or all molded.

[0392] The inner diameter of the small diameter tube 10108 may be about 1.8-2.0 mm. In some embodiments, the ID may be about 1.6-1.8 mm. In some embodiments, the ID may be about 1.4-1.6 mm. In some embodiments, the ID1 may be about 1.2-1.4 mm. In some embodiments, the ID may be about 1.0-1.2 mm. In some embodiments, the ID may be about 0.8-1.0 mm. In some embodiments, the ID may be about 0.5-0.8 mm. In some embodiments, the ID may be about 0.2-5 mm. In some embodiments, the ID may be less than about 4 mm. In some embodiments, the ID may be less than about 3 mm. In some embodiments, the ID may be less than about 2 mm.

[0393] Some embodiments include a drainage tube with a small diameter inner lumen. For example, in some embodiments, the diameter of the inner lumen is about 2 mm. In some embodiments, the diameter of the inner lumen is about 1 mm. In some embodiments, the diameter of the inner lumen is about 3 mm. In some embodiments, the diameter of the inner lumen is less than about 2 mm, and in some embodiments, the diameter of the inner lumen is less than about 1 mm. In some embodiments, the diameter of the inner lumen is less than about 3 mm.

[0394] In some embodiments, the drained urine can be used to "clean" any air bubbles in the drainage tube or urine collection reservoir. Urine can be circulated back into the drainage tube to increase the volume in the drainage tube and also to help "clean" any air bubbles in the tube and / or reservoir. The controller compensates for the regenerated urine when calculating urine output.

[0395] In some embodiments, pressurized air may be introduced into the drainage tube and / or urine collection container. The forced air pops and / or compresses air bubbles and also forces the urine up against the surface of the system, reducing the formation of air bubbles. The cross-sectional area of ​​the drainage tube may decrease, remain the same, or increase as the drainage tube transitions to the flat section.

[0396] horizontalization

[0397] In embodiments where the urine volume is measured in the urine collection container using ultrasound, it is important that the ultrasound has a surface (i.e., the surface of the urine volume) that is approximately 90 degrees away from the ultrasound sensor. Also, if the system is tilted even a few degrees, the ultrasound sensor may not be able to sense the surface of the urine and an accurate urine volume measurement may not be obtained. To compensate for this, the urine collection container or base / control may be attached to the bed via a self-leveling attachment, e.g., mounted on rollers such that gravity automatically levels the base when attached.

[0398] In some embodiments, slight angles in the system are handled by creating a "rough" surface on the urine volume in the urine collection reservoir. The "rough" surface provides multiple angles for ultrasound reflection, some of which are approximately 90 degrees from the ultrasound sensor / transducer. The roughness may be created by bubbling the urine with air or other gases, or by vibrating the urine collection reservoir and / or urine. The vibration may be mechanical, ultrasonic, or the like. A floating plate that floats on the surface of the urine may have a rough, concave, or convex underside. The floating beads remain in the reservoir as the urine is drained because their diameter is too large to exit the reservoir as the urine is drained. To prevent the beads from entering the overflow area, mechanisms such as mesh, constriction, small diameter openings, etc. may be used. In addition, as described above, angled baffles and angled or tapered walled cassettes (or urine collection chambers) may be used to accurately measure urine volume.

[0399] Priming the Pressure Balloon

[0400] A very small amount of air or fluid may be needed primarily to regulate the pressure of the pressure balloon for optimal pressure sensing measurements. For this reason, an air / gas / fluid restrictor may be utilized between the priming fluid and the pressure balloon. The restrictor allows the priming pump to operate with less air for more accurate pressure balloon priming. The restrictor may include a foam insert, a narrowing of the fluid lumen, or any other suitable restrictor.

[0401] General improvements

[0402] In some embodiments, sensors in the bed, patient, sensing Foley catheter system, or elsewhere detect whether the patient is supine or not. Pressure measured in the bladder may rise when the patient is not supine, adversely affecting data for analysis by the controller. As a result, the controller may ignore pressure data collected while the patient is not supine, or may stop collecting pressure data during this time. Alternatively, the pressure measurement itself may be used to detect when the patient is not supine. A sudden increase in pressure, or an increase above a certain threshold, may indicate a state in which the patient is sitting, moving, coughing, etc. Different pressure profiles may indicate different events. Patient turning to prevent bed sores may be tracked in this manner.

[0403] In some embodiments, electrocardiogram measurements obtained via leads attached to the sensing Foley catheter system or obtained independently are used to synchronize the heart rate measured via the intrabladder heart rate with the electrocardiogram.

[0404] In some embodiments, the bed angle may be used by the controller as an input parameter for calculations such as IAP or APP. For example, raising the body angle (raising the patient's head position) leads to an increase in IAP. This increase will be different for healthy and unhealthy patients. As a result, determining the IAP at different bed angles may provide additional information about the patient's health. Also, to temporarily stabilize a patient with a high IAP, the IAP may be lowered by lowering the head position.

[0405] In some embodiments, the sensing Foley catheter has at least one pressure sensor or lumen in fluid communication with an external pressure sensor. This pressure sensor would sense the pressure in the lumen rapidly or at high frequency (ideally faster than 1 Hz) and allow monitoring of physiological signals in the lumen. In some embodiments, the pressure lumen may be manually or automatically pressurized and / or depressurized while the pressure is monitored continuously or intermittently. In embodiments where the pressure lumen includes a pressure balloon, the balloon may be inflated and / or deflated while the pressure exerted by the body on the pressure balloon is monitored. The pressure lumen is capable of transmitting pressure waves from the body cavity, one of which is the cardiac pulsation caused by the inflow of blood into the lumen organ and / or surrounding tissue. Pulsating pressure from cardiac pulsation and / or respiratory motion can be used to measure pulmonary and cardiovascular pressures. In addition, the pressure in the pressure lumen / balloon may be increased above a threshold (i.e., 100 mmHg) and then slowly decreased through the sensing range to determine the origin of the pulse pressure, the vanishing point of the pulse pressure, and / or the relative increase / decrease in pressure pulse size. The origin / vanishing point or relative increase / decrease of the pressure pulsation sensed by the pressure sensor can be correlated with blood pressure, perfusion pressure, mean arterial pressure, stroke volume, stroke volume variation, respiratory effort, pulmonary pressure transmission, and other pulmonary, gastrointestinal, renal, or cardiovascular parameters. This process is similar to a blood pressure cuff, where the pressure in the cuff is increased above the blood pressure and then the pressure in the cuff is slowly decreased until the blood pressure waveform (heartbeat) appears or disappears.

[0406] Figure 102 shows the pressure waveform and its disappearance as the pressure balloon is inflated. Note that above mean arterial pressure, cardiac pulsation is reduced and / or disappeared. From this relative pressure waveform, the mean arterial pressure can be derived if there is sufficient data to correlate the degree of disappearance at the relative pressure points with the mean arterial pressure. Similar uses can be made for pulmonary artery pressure and other pressures detectable within body cavities, such as pulmonary pressure.

[0407] In some embodiments, the pressure sensor / lumen is a capsule, or balloon, or reservoir that can be slowly inflated or filled while pressure is monitored using an external transducer. In some embodiments, the pressure sensor is associated with a urinary catheter, such as a Foley catheter. Alternatively, the pressure sensor may be associated with a nasogastric, orogastric, or rectal tube. In further embodiments, the pressure sensor device and associated pressure augmentation device may be fully implantable. In tissue perfusion embodiments, pressure sensing may be inflated within the urethra or against an intraluminal surface, and pulse oximetry may be performed to sense the blanching and / or perfusion of intraluminal tissue at each pressure to determine tissue perfusion pressure.

[0408] In some embodiments, the catheter can use multiple measured parameters synergistically to improve the quality of the data analysis. In one embodiment, the catheter incorporates a sensor to capture an electrocardiogram signal, either internally, such as through the urethra or bladder, or externally, such as through a sensor placed on the leg or lower back. This signal can be used to synchronize other measured parameters (such as stroke volume) synchronized to the cardiac cycle with the electrical signal, and noise can be removed by taking the average or median signal from many individual samples. In another embodiment, the respiratory signal is used to guide which cardiac pressure signal should be used for stroke volume variability analysis by waiting for a model waveform to appear before performing the analysis.

[0409] FIG. 103 illustrates a method for synchronizing a cardiogenic signal (such as pressure fluctuations in the bladder caused by a pulse in the nearby abdominal aorta) to obtain a clean signal for analysis. If the ECG is captured synchronously with another cardiac signal of interest, the individual samples can be synchronized, for example, using the R wave of the ECG. In this figure, multiple pressure samples are captured and then superimposed using the R wave of the ECG for alignment. A median signal is then calculated by taking the median of all pressure samples at the same time during the cardiac cycle. The average value could also be used. In this way, random noise is filtered out, as an abnormally high value due to noise in one sample is countered by an equally abnormally low value in another sample. As more data points are added, the underlying signal becomes stronger and can be used for analysis. For example, in the pressure signal shown, the peak-to-peak amplitude of the signal can be used to derive the relative stroke volume.

[0410] FIG. 104 illustrates a method for using respiratory pressure signals to inform cardiac pressure signal analysis to determine stroke volume variation (SVV). This method is particularly useful in non-ventilated patients, i.e., patients not using a ventilator. Existing stroke volume measurement techniques, e.g., thermodilution and pulse contour analysis, are limited in their ability to perform measurements of stroke volume variation (variation in stroke volume between inspiration and expiration) due to their blindness to the respiratory cycle. Using intraluminal pressure, such as with a Foley catheter in the bladder, as described herein, is advantageous in that respiratory and cardiac signals can be captured simultaneously (as well as the slower moving intraperitoneal pressure). In this manner, the device of the present invention can discriminate and select respiratory cycles to use for analysis of stroke volume variation because certain characteristics (e.g., respiratory rate, magnitude, etc.) are suitable for appropriate analysis. This figure shows a sample pressure signal captured from the bladder. In the raw pressure signal above, the larger variations are due to breathing and are selected for analysis based on, for example, wave width, amplitude, or peak value. Other characteristics not shown may also be used to define suitable waves, including slope, area under the curve, shape, frequency, pattern, repeatability, etc. A curve amplitude filter may be used, where curves with amplitudes above a certain value may be used and curves below the same value or below a certain other value may not be used in the SVV calculation. The bottom figure shows the same signal after passing through a high pass filter and a low pass filter. The high pass filter leaves the cardiac signal below (dashed line) and the low pass filter leaves the respiratory signal below (solid line). In this example, the difference in cardiac signal strength between the peaks and valleys of the respiratory signal (e.g., peak-to-peak value, etc.) may be used to calculate stroke volume variability.

[0411] Respiratory rate and other parameters may be sensed via a sensing Foley catheter or may be sensed or obtained by any conventional or non-conventional means. Other parameters that may be collected include tidal volume, spirometry, respiratory flow parameters, data collected via spirometry, expiratory effort, inspiratory effort, etc. Any of these parameters may be used to aid in the calculation of stroke volume variability and / or other cardiac parameters.

[0412] The filter used to determine which pressure peaks are used in the SVV calculation may be based on any of the pressure curve parameters disclosed herein. In addition, the SVV calculation itself may be used to determine which pressure curve peaks are used in the calculation. For example, SVV typically falls within a range of about 10%. The systems disclosed herein may include or exclude pressure curve data based on the resulting SVV calculation falling within a particular range of values, such as about 10%.

[0413] The calculation of SVV may also vary from patient to patient. For example, the pressure curve peak filter may be based on amplitude, but the cutoff amplitude may be patient specific and based on the average value of the pressure curve for that patient, or other parameters. Alternatively, the filter may be based on multiple patients, or multiple patients within a particular category, such as a particular disease state.

[0414] The signal and / or SVV calculation may also be filtered for patient movement and / or other artifacts such as coughing, moving, sneezing, etc.

[0415] In addition, a calculated SVV result with very low or absent SVV may be an indication of fluid overload and appropriate treatment may be indicated.

[0416] In some embodiments of the disclosed system, the patient can be prompted to breathe in a particular way. For example, based on the shape of the pressure curve (peak amplitude, frequency, etc.), the system can prompt the patient to breathe deeper, breathe slower, breathe normally, etc. The resulting breathing pressure curve can then be taken into account in the SVV calculation. This type of prompting may be performed by the system if the pressure curve is insufficient to provide an SVV calculation, or for other reasons.

[0417] 105A and 105B are two side views showing the base piece of the sealing mechanism between the cassette and the control. Typically, the base piece shown in 105A and 105B would be connected to the cassette and the pins shown in 106 would be connected to the control. However, the connector may be attached in the reverse manner with the pins connected to the cassette and the base connected to the control. The purpose of the sealing mechanism is not only to connect the lumens in the cassette to the lumens in the control when the cassette is connected to the control, but also to seal the lumens in the cassette when the cassette is disconnected from the control. For example, the cassette may be temporarily disconnected from the monitor / control when a patient is taken to surgery or moved from one room to another. While the cassette is disconnected from the control, it would be desirable to seal the lumens of the cassette to prevent contamination and to prevent urine, liquids or gases from escaping or entering the system.

[0418] For example, lumens such as the pressure balloon lumen (such as pressure transducer interface 1026), vent lumen 1180, cassette pump interface 1148, and / or cassette pressure interface 1150 may have connectors such as these.

[0419] 105A and 105B show the base portion 1050 of the connector. The base portion may be manufactured from a compressible, strong, inert material such as silicone or rubber. The base portion 1050 includes a base head 10504, a base stem 10508, and a base anchor 10502, and a slit 10506 having a length L3. Preferably, the slit 10506 is a single straight slit, but a sharp knife may be used after molding the base to ensure that the slit does not have rounded edges and can seal completely in a relatively relaxed state. When the base 1050 is connected to a lumen, fluid cannot flow through the slit in the base.

[0420] The pin portion 1060 shown in FIG. 106 includes a pin head 10604 and a pin stem 10602 that includes a lumen therethrough. The pin stem 10602 has an outer diameter D3. The pin 1060 fits within a slit 10506 in the base 1050 and, when so positioned, allows fluid to pass through the sealing mechanism. In some embodiments, L3 is approximately the same as D3.

[0421] 107A and 107B show a pin 1060 inserted into a slit 10506 in the base 1050, which allows fluid to flow through the lumen of the pin and through the sealing mechanism.

[0422] 108 illustrates a base portion 1050 of the sealing mechanism on the back of the cassette that is configured to snap into an opening on the control. The base portion of the sealing mechanism shown is connected to a pressure balloon lumen interface 10802, a vent lumen interface 10804, a cassette pump interface 10806, and a cassette pressure interface 10808 (for measuring IAP). Note that all or some of the cassette interfaces may use these types of sealing mechanisms, or none of them. For example, the pressure interface 10808 for measuring IAP does not need to be sealed when the cassette is disconnected and may use a different type of connector.

[0423] FIG. 109 illustrates the operation of the sealing mechanism when the cassette is connected to the control. The cassette 1022 is shown in cross section with one of the sealing mechanisms in place. The base 1050 is attached to the cassette portion and would be sealed and sealed in the absence of the pin 1060. The pin 1060 is connected to the control (not shown) and when the cassette 1022 is snapped into place in the control, the pin 1060 is inserted into a slit in the base 1050, allowing fluid to flow from the control into the cassette and / or from the cassette to the control. The connection may include a filter, shown here as filter 10902.

[0424] Figure 110 shows approximate dimensions of a base 1050 according to one embodiment. These dimensions may vary depending on the application.

[0425] FIG. 111 illustrates some of the forces that are applied to the base 1050 when it is fully mounted in the cassette. These forces are due to the diameter of the mounting hole versus the diameter of the stem 10508, and the thickness of the cassette walls versus the length of the stem 10508. Additionally, when the cassette is attached to the control, compressive forces may press against the base head 10504. These forces tend to enhance the sealing of the base 1050 whether or not the slit has a pin inserted. That is, based on the dimensions and shape of the base, the slit will have a force exerted on it that helps it to stay either closed on itself or closed on the pin. A force is pushing the slit inwards. Also, because the head 10504 is slightly concave (like a mushroom) at the bottom, it tends to widen at the bottom (wide area) and compress at the top (where the slit opening is). This is especially true if the thickness of the cassette walls is greater than the length of the stem 10508.

[0426] In some embodiments, multiple drainage lumens may be used to prevent airlock. The proximal and / or distal openings may be staggered. The lumens may be incorporated into single or multiple tubes, with or without siphoning. For example, two drainage lumens may be used, three drainage lumens may be used, four drainage lumens may be used, five drainage lumens may be used, six drainage lumens may be used, seven drainage lumens may be used, eight drainage lumens may be used, or nine or more drainage lumens may be used.

[0427] In any of the embodiments disclosed herein, the vent tube may be connected to a standard or non-standard Foley catheter by attaching to the sampling port of the Foley catheter, or to a barb near the Foley catheter, or anywhere in the drainage system. See, e.g., FIG. 112.

[0428] FIG. 112 illustrates an embodiment including a venting mechanism / vent tube that can be added to any urinary drainage system that includes a sampling port 1004, or any other suitable port. In this embodiment, the venting mechanism 11200 can turn the sampling port 1004 into a vent for the system to avoid airlocks. The venting mechanism 11200 includes a vent tube 11202 and optionally a valve 11204 and / or a filter 11206. The venting mechanism may also include a needle, or puncture mechanism, or blunt tube 11208 that punctures or opens / accesses the sampling port 1004 and also holds the lumen open in fluid communication with the drainage lumen 1012 to perform the venting function. In this illustration, the sampling port is shown as part of the barb 1016, but the sampling port may be anywhere in the drainage system. Alternatively, any other port or access point may be used. This embodiment can be used with or without a vacuum pump. The vent tube may be rigid, flexible, or bendable. The venting mechanism may include means for suspending the vent tube above the level of the bladder, for example, 1-10 cm. The length of the vent tube may be greater than about 1 cm. Alternatively, the length of the vent tube may be greater than about 2 cm. Alternatively, the length of the vent tube may be greater than about 3 cm. Alternatively, the length of the vent tube may be greater than about 4 cm. Alternatively, the length of the vent tube may be greater than about 5 cm. Alternatively, the length of the vent tube may be greater than about 10 cm. The inner diameter ID of the vent tube may be less than about 5 mm. Alternatively, the ID of the vent tube may be less than about 4 mm. Alternatively, the ID of the vent tube may be less than about 3 mm. Alternatively, the ID of the vent tube may be less than about 2 mm. Alternatively, the vent tube ID may be less than about 1 mm.

[0429] Note that in this view, the vent tube 11202 is shown terminating in the atmosphere, but the vent tube may be connected to a drainage bag as shown in FIG. 11E. If a valve and vent are present, the valve may be between the sampling port and the vent, or the vent may be between the sampling port and the valve. This type of vent mechanism may be implemented at the sampling port after an initial amount of urine has been drained from the bladder. This type of vent mechanism may be incorporated into a strap or patch intended to secure the barb to the patient's leg or other location. The vent mechanism / vent tube of this embodiment may have one or more small diameter sections with lengths as shown in FIG. 11D. For example, a section of the vent tube 11202 may be relatively small diameter and relatively long to prevent urine from traveling through the vent tube and reaching the valve and / or filter.

[0430] Rather than using a puncture mechanism 11208 in conjunction with the sampling port 1004, a puncture mechanism may be used along the tubing of the catheter or drainage tube. Alternatively, a mechanism may be used where the port is normally closed but will accept an add-on vent mechanism / vent tube. For example, a sealing mechanism pin configuration may be used where the base is on the catheter / drainage tube and the pin is part of the vent mechanism / vent tube, or vice versa, as shown in FIGS. 105-111. In some embodiments, the port 1004 may be on an add-on barb or connecting piece that is meant to be placed between the catheter and the drainage tube.

[0431] Any of the vent tube embodiments disclosed herein may additionally or alternatively be used to vent a drainage bag or cassette. For example, bag vent 1142 shown in FIG. 10A may incorporate any of the vent tube configurations. Alternatively, for example, vent 1180 shown in FIG. 11A may incorporate any of ...

Claims

1. 1. A system for assessing a patient's health status, comprising: a drainage tube (1001; 1012) configured to be in fluid communication with at least one opening located near or at the distal end of the catheter (102; 1000); a urine collection reservoir (1022) in fluid communication with the drainage tube (1001; 1012) for receiving a volume of urine from the patient, the urine collection reservoir (1022) being configured to empty when a predetermined volume within the urine collection reservoir (1022) is reached; a controller in communication with the urine collection reservoir (1022), the controller being configured to measure the volume of urine in the urine collection reservoir (1022); Equipped with the controller is configured to monitor the urine volume over a first time period when it is determined that the urine volume from the patient exceeds a urine volume threshold; the control unit is further configured to monitor the urine volume from the patient over a second time period after the first time period and measure a second urine volume over the second time period; The control unit is further configured to determine a risk of acute kidney injury (AKI) when the second urine volume from the second period is below the urine volume threshold and the urine volume from the first period shows a decreasing trend.

2. The system of claim 1 , further comprising a valve configured for unidirectional flow and configured to be in fluid communication with the drainage tube (1001; 1012).

3. 2. The system of claim 1, further comprising a pump (2918; 3106; 6606) in fluid communication with the drainage tube (1001; 1012) and configured to apply negative pressure to the drainage tube (1001; 1012).

4. 4. The system of claim 3, wherein the pump (2918; 3106; 6606) is configured to operate cyclically.

5. 4. The system of claim 3, wherein the control unit is configured to communicate with the pump (2918; 3106; 6606) and to operate the pump (2918; 3106; 6606) to apply negative pressure to eliminate an airlock from the drainage tube (1001; 1012).

6. 6. The system of claim 5, wherein the control unit is further configured to operate the pump (2918; 3106; 6606) to apply the negative pressure at a first level and then at a second level to eliminate an airlock from the drainage tube (1001; 1012).

7. 7. The system of claim 6, wherein the control unit is further configured to operate the pump (2918; 3106; 6606) to apply the negative pressure at the second level immediately after the airlock is cleared from the drainage tube (1001; 1012).

8. 7. The system of claim 6, wherein the control unit is further configured to operate the pump (2918; 3106; 6606) to apply the negative pressure at the second level for a predetermined period of time after the airlock is cleared from the drainage tube (1001; 1012).

9. The system of claim 1 , wherein the control unit is configured to collect the urine volume on at least an hourly basis.

10. The system of claim 1 , wherein the urine volume threshold comprises 0.5 mL / kg / hour.

11. The system of claim 1 , wherein the first period of time is at least three hours.

12. The system of claim 11 , wherein the second period of time is three hours or less.

13. The system of claim 1 , wherein the second period of time is at least one hour.

14. The system of claim 1 , wherein the control unit is further configured to determine the risk of AKI based on the patient's urine volume and weight.

15. The system of claim 1 , wherein the control unit is further configured to determine the risk of AKI based on the patient's urine volume and intra-abdominal pressure.

16. The system of claim 15, wherein the control unit is further configured to determine the risk of AKI based on the urine volume and the intra-abdominal pressure and temperature of the patient.

17. The system of claim 1 , wherein the control unit is further configured to determine the risk of AKI based on the patient's urine volume and heart rate.

18. The system of claim 1 , wherein the control unit is further configured to determine the risk of AKI based on the patient's urine volume and respiratory rate.

Images