Systems, devices, and methods for draining and analyzing bodily fluids

Abstract

To provide a catheter system that prevents the formation of an airlock in a drainage tube, removes the airlock if one is formed, and improves the accuracy of measuring urine volume in an automated manner. [Solution] The catheter system comprises a catheter having at least one opening at or near its distal end, a barb in fluid communication with the proximal end of the catheter, a drainage tube in fluid communication with the at least one opening, an airway tube in fluid communication with the barb, a one-way valve positioned in line with the airway tube and close to the barb, and a controller in communication with the one-way valve, which is controlled by applying negative pressure to the drainage tube to open the one-way valve and allow fluid to pass through the airway tube.

Description

Technical Field

[0003]

[0001] This application claims the benefit of U.S. Provisional Application No. 62 / 448,237, filed Jan. 19, 2017; U.S. Provisional Application No. 62 / 503,209, filed May 8, 2017; and U.S. Provisional Application No. 62 / 563,546, filed Sep. 26, 2017, each of which is hereby incorporated by reference in its entirety. This application is also related to International Patent Application No. PCT / US2011 / 043570, filed Jul. 11, 2011; PCT / US2012 / 028071, filed Mar. 7, 2012; PCT / US2016 / 060365, filed Nov. 3, 2016; PCT / US2015 / 052716, filed Sep. 28, 2015; PCT / US2014 / 044565, filed Jun. 27, 2014; PCT / US2015 / 010530, filed Jan. 7, 2015; and PCT / US2016 / 060365, filed Nov. 3, 2016, and each of these applications is hereby incorporated by reference herein as if each such individual publication or patent application was specifically and individually indicated to be incorporated by reference in such manner.

[0002] The present invention relates to the field of medical devices, particularly devices that assist in bladder emptying, measure various urinary parameters such as urine output and oxygen pressure, urine conductivity and urine specific gravity, monitor kidney function, analyze urinary parameters including urine volume including the presence of infection, and track and / or manage fluid administration. The present invention further relates to medical devices capable of sensing physiological data based on sensors incorporated into catheters adapted to be present in any of the urinary tract, gastrointestinal tract, rectal location, preperitoneal, pleural cavity or other body cavity.

[0003] All publications and patent applications mentioned herein are hereby incorporated by reference herein to the same extent as if each such individual publication or patent application was specifically and individually indicated to be incorporated by reference as such.

Background Art

[0004] It is estimated that 10% of all hospitalized and nursing patients receive an indwelling urinary catheter. Almost all critically ill patients receive one indwelling urinary catheter, and in the ICU, this involves monitoring urine output every hour. The amount of urine produced is an indicator of fluid status and renal function. However, numerous error factors can lead to inaccurate measurements of this important indicator.

[0005] The most common device used to drain fluid from the bladder is the Foley catheter. Since its introduction, the design of the flexible tube with a fixed balloon and a small hole that allows urine to drain through the central lumen has remained largely unchanged. However, current Foley catheter designs have been found to leave a large residual volume in the bladder, for example, more than 50 mL in supine patients. See 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. In one study, the average residual volume was 96 mL in the ICU and 136 mL in general wards. See Garcia et al., Traditional Foley Drainage Systems - Do They Drain the Bladder?, J Urol. 2007 Jan;177(l):203-7;discussion 207. Large amounts of residual urine are often found in the drainage tube connecting the Foley catheter to the drainage bag, or in other locations within the drainage system.

[0006] Residual urine in the bladder and drainage tube is a result of large air bubbles (airlocks) forming inside the tube, obstructing the flow of urine from the bladder to the urination bag. Consequently, it has become a routine procedure for nurses to manipulate the urinary catheter before measuring urine output, which helps to empty the tube. In the ICU, this is a highly repetitive and inaccurate process, as measurements are taken every hour. A more accurate and automated method for measuring urine output is needed.

[0007] Furthermore, the urine collection system includes an opportunity to measure and analyze urine parameters.

[0008] In addition to improving urine output measurement and urine parameter analysis, the urinary drainage catheter itself provides an untapped opportunity for detecting, collecting, and analyzing further patient parameters.

[0009] Furthermore, many types of medical devices are designed to control the treatment and / or maintenance of a patient. For example, ventilators can control, among other things, the patient's respiratory rate, volume, and / or gas mixture. Intravenous delivery (IV) 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 precisely controlled through various settings, etc. Nurses or other practitioners can check various patient parameters and adjust medical device settings accordingly. There is a need for controllers that automatically or semi-automatically control the settings of treatment devices using patient parameters. [Overview of the project] [Means for solving the problem]

[0010] Widely used, low-cost, and easily deployed by medical professionals, Foley catheters can be used as a medium for deriving critical diagnostic information by modifying them and / or by adding functionality to them. The techniques disclosed herein provide highly decomposed and previously unavailable delivery of diagnostic information, which may be derived from Foley catheters equipped with intraperitoneal pressure (and other) sensing capabilities.

[0011] In addition, it has been found that the development of airlocks significantly distorts intraperitoneal pressure measurements. Furthermore, a non-empty bladder can also adversely affect bladder pressure measurements. The techniques disclosed herein provide detection and removal of airlocks during intraperitoneal pressure measurement or other settings, as well as more complete bladder drainage.

[0012] The technology disclosed herein aims to more effectively empty the bladder, prevent the formation of airlocks within the drainage tube and subsequent discharge from the drainage tube, and improve the accuracy of measuring urine volume in an automated manner. The disclosed technology also aims to improve the monitoring of fluid status, renal function, and other important patient parameters by incorporating additional urine measurements, including oxygen pressure, conductance, and specific gravity, gas pressure, turbidity, infection, and sediment.

[0013] The disclosed technology also relates to a Foley catheter for sensing physiological data from a patient's bladder and / or urinary tract, the physiological data including, in particular, data collected by conversion to signals suitable for high-fidelity pressure sensing and processing. In some embodiments, the pressure-sensing Foley catheter may further be capable of sensing clinically important temperature and specimens. Examples of physiological parameters that a sensing Foley catheter system can measure (time-specific measurements and trends over time) include urine volume, respiratory rate, heart rate, heart rate variability, stroke volume, stroke volume variability, intraperitoneal pressure (IAP), tissue oxygenation, tissue gas content, pulse transit time, pulmonary blood volume variability, body temperature, blood content, and other patient parameters.

[0014] One embodiment of a drainage assembly configured to prevent the accumulation of negative pressure may generally comprise an elongated catheter having a first end configured to be inserted into a body cavity. The catheter may have at least one opening at or near the first end that fluidly communicates with a catheter lumen defined through it, a drainage lumen that fluidly communicates with a second end of the catheter, a reservoir that fluidly communicates with the drainage lumen, and a venting mechanism that fluidly communicates with the drainage lumen and the positive pressure lumen. A valve may be positioned within the venting mechanism and configured to remain in a closed position until a first pressure level in the drainage lumen drops to a second pressure level, after which the valve moves to an open position. Alternatively, a vent can be positioned to fluidly communicate with the valve, and the venting mechanism may be configured to prevent wetting of the vent from the fluid in the drainage lumen, and a controller communicating with the reservoir may be configured to determine the amount of fluid collected in the reservoir.

[0015] In another embodiment, the drainage assembly may be configured to prevent the accumulation of negative pressure, generally including an elongated catheter having a first end configured to be inserted into a body cavity, the catheter having at least one opening at or near the end that fluid-communicates with the catheter lumen defined therethrough. The drainage lumen is fluid-communicated with a second end of the catheter, and includes a positive pressure lumen fluid-communicated with the drainage lumen, a reservoir fluid-communicated with the drainage lumen, and a ventilation mechanism connected to the drainage lumen, the ventilation mechanism configured to prevent wetting of the ventilation holes from the fluid in the drainage lumen. A controller may communicate with the reservoir, and the controller may be configured to determine the amount of fluid collected in the reservoir, and may also include a valve configurable between a closed position and an open position, the valve moving from a closed position to an open position when a first pressure level applied to the valve drops to a second pressure level in the reservoir.

[0016] Certain patient parameters that can be measured and / or determined by the disclosed technology may be affected and / or influenced by the treatment of the patient by the medical device. For example, a patient's urine output, respiratory rate, heart rate, stroke volume, stroke volume variability, intraperitoneal pressure (IAP), tissue oxygenation, tissue gas volume, body temperature, blood volume, and other patient parameters may be affected and / or influenced by the medical treatment. Some examples of medical treatment controlled by medical devices include respiratory rate and content controlled by a ventilator, IV rate and content controlled by an IV infusion controller, drug delivery controlled by a drug delivery device or IV controller, ascites volume controlled by a urination pump, drainage pump, and other treatments controlled by other medical devices.

[0017] One embodiment of a system for analyzing body fluids generally comprises an elongated catheter having an expandable balloon located at or near the distal end of the catheter, further defining one or more openings adjacent to the balloon; a proximal end of the catheter; a ventilation mechanism configured to allow air to pass through when negative pressure is applied to the ventilation mechanism; a first lumen connected to the ventilation mechanism and in fluid communication with one or more openings; a second lumen balloon in fluid communication; a reservoir connected to the proximal end of the first lumen and in fluid communication with one or more openings; and a controller configured to connect to the reservoir and programmed to control the pressure in the first lumen, further programmed to monitor urine output received from the patient in the reservoir and determine intra-abdominal pressure, partially based 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 physical parameters from a patient, the method may generally include: positioning an elongated catheter having an expandable balloon located near or distal to the distal end of the catheter in at least a partially filled body lumen; receiving urine from one or more openings defined along the catheter adjacent to the balloon, and further receiving body fluids in a reservoir outside the body lumen, a body fluid fluid lumen in fluid communication with one or more openings; a ventilation mechanism that expels air through a ventilation mechanism in communication with the fluid lumen when negative pressure is applied to the fluid lumen, and analyzing the amount of urine contained in the reservoir via a controller programmed to control the negative pressure; determining the patient's intraperitoneal pressure partially based on changes in pressure within the balloon; and storing one or more parameters of patient data via the controller.

[0019] Some embodiments of a sensing Foley catheter system include a loop controller that receives one or more data points regarding patient parameters and uses this information to control one or more medical treatment devices. The loop controller can be integrated with a device that measures patient parameters, a medical device, or both.

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

[0021] Other parameters that can be measured and / or determined via a sensing Foley catheter include urine specific gravity and pulse pressure variability. These parameters may be used to assist in the control of medical treatment devices such as ventilators and / or infusion and / or hydration devices.

[0022] Urine specific gravity is a measure of the number and weight of solute particles in urine. The normal range is approximately 1.010 to 1.030. Higher readings may indicate dehydration or other conditions. Lower readings may indicate fluid overload or other conditions. Measurements can be performed using a sensing Foley catheter sensor. The results may indicate an increase (in case of dehydration) or decrease (in case of fluid overload) infusion rate to the patient. The results may also indicate changes in ventilation parameters or drug infusion.

[0023] Pulse pressure variability can be a predictor of fluid responsiveness to medical devices such as ventilators and / or fluid infusion systems. Sensing Foley catheters can record pressure waveforms, and controllers can identify maximum and minimum pressure pulses that coincide with the respiratory cycle. Controllers can calculate pulse pressure variability. Pulse pressure variability helps determine whether a particular patient will respond to fluid therapy. Controllers can also use pulse pressure variability to control the treatment of the feedback loop. If pulse pressure variability is large, the patient may need more fluid. If pulse pressure variability is low, less fluid will be needed.

[0024] A sensing Foley catheter system can measure cardiac activity via pressure sensing within the bladder. While the sensing Foley catheter can measure both respiratory and cardiac activity, patient respiratory measurements can distort cardiac measurements because a patient's respiratory rate and heart rate frequency may be similar to each other. To overcome this problem, some embodiments of the controller pause the ventilator at the end of one or more inspiratory points and / or at the end of one or more expiratory points (each time, for only a few seconds, e.g., 1-3 seconds, or e.g., 1-4 seconds), thereby capturing cardiac waveforms without respiratory distortion. By capturing detailed cardiac waveforms in this manner, the controller can determine stroke volume variability (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 inspiratory and / or expiratory points.

[0025] In another embodiment, the catheter system may generally comprise a catheter having at least one opening near or at the distal end of the catheter, a barb communicating fluidly with the proximal end of the catheter, a drainage tube communicating fluidly with at least one opening, and a vent tube communicating fluidly with the barb. A one-way valve may be positioned proximal to the barb, in line with the vent tube, and a controller may communicate with the one-way valve, which is programmed to apply negative pressure to the drain, causing the one-way valve to open and the fluid to pass through the vent tube.

[0026] In another embodiment, one way to drain fluid generally involves placing near or distal to the proximal end of a catheter having at least one opening near or distal to the distal end of the catheter, a catheter system having a barb in fluid communication with the proximal end of the catheter and a drainage tube in fluid communication with the at least one opening, near the body of the subject. A controller in communication with a one-way valve can be actuated when the one-way valve is aligned with the ventilation tube and in fluid communication with the barb, and the one-way valve is further positioned proximal to the barb. Applying a negative pressure to the drainage tube causes the one-way valve to open and fluid to pass through the ventilation tube.

[0027] The novel features of the invention are set forth. A better understanding of the features and advantages of the invention will be obtained by reference to the following detailed description which sets forth illustrative embodiments in which the principles of the invention are utilized, and to the appended drawings.

Brief Description of the Drawings

[0028] [Figure 1] FIG. 1 shows an embodiment of a sensing Foley catheter. [Figure 2] FIG. 2 shows an example of respiratory rate sensing data. [Figure 3] FIG. 3 shows a detailed portion of a respiratory profile. [Figure 4] FIG. 4 shows an example of heart rate and relative cardiac output sensing data. [Figure 5] FIG. 5 shows data regarding relative cardiac output sensing during a human leg lift exercise. [Figure 6] FIG. 6 shows an example of peritoneal sensing data. [Figure 7] FIG. 7 shows an example of peritoneal sensing data. [Figure 8] FIG. 8 shows the relationship between intra-abdominal pressure, respiratory wave pressure, and cardiac pressure. [Figure 9] FIG. 9 provides a flowchart of an embodiment of the method. [Figure 10A] FIG. 10A shows an embodiment of a sensing Foley catheter system. [Figure 10B] Figure 10B shows the temperature logic used in controllers of several embodiments. [Figure 10C] Figure 10C shows a detailed diagram of the airlock cleaning mechanism and fluid collection and analysis system shown in Figure 10A. [Figure 10D] Figure 10D shows disposable components of an embodiment of a sensing Foley catheter system. [Figure 11A] Figure 11A shows various embodiments of the sensing Foley catheter system. [Figure 11B] Figure 11B shows various embodiments of the sensing Foley catheter system. [Figure 11C] Figure 11C shows various embodiments of the sensing Foley catheter system. [Figure 11D] Figure 11D shows an embodiment of a vent pipe. [Figure 11E] Figure 11E shows another embodiment of the sensing Foley catheter system. [Figure 11F] Figure 11F shows a graph of the valve opening cycle. [Figure 12A] Figure 12A shows another embodiment of the sensing Foley catheter system. [Figure 12B] Figure 12B shows another embodiment of the sensing Foley catheter system. [Figure 13] Figure 13 shows another embodiment of the sensing Foley catheter system. [Figure 14A] Figure 14A shows an embodiment of a foldable drainage tube located within a torsion-resistant tube. [Figure 14B] Figure 14B shows an embodiment of a foldable drainage tube located within a torsion-resistant tube. [Figure 15] Figure 15 shows an example of a cleaning mechanism for a sensing Foley catheter system. [Figure 16] Figure 16 shows an example of a cleaning mechanism for a sensing Foley catheter system. [Figure 17] Figure 17 shows an embodiment of a sensing Foley catheter system equipped with a drainage tube having a gas sampling lumen. [Figure 18] Figure 18 shows an active ventilation system equipped with vents and a pump. [Figure 19] Figure 19 shows an embodiment of a sensing Foley catheter system with additional vents for pressure relief and sterility. [Figure 20] Figure 20 shows an embodiment of a sensing Foley catheter system equipped with a pressure relief vent and a relief valve. [Figure 21] Figure 21 shows an embodiment of a collection container, chamber, or cassette that may be included in a sensing Foley catheter system for detecting bacteria, blood, and / or other substances in urine using UV / optical spectroscopy. [Figure 22] Figure 22 shows the various absorption wavelengths of E. coli, red blood cells, and plasma in urine. [Figure 23] Figure 23 shows an embodiment of a cassette including a baffle or flap. [Figure 24] Figure 24 shows graphs illustrating pressure balloon priming methods in several embodiments. [Figure 25] Figure 25 shows graphs illustrating pressure balloon priming methods in several embodiments. [Figure 26] Figure 26 shows flowcharts of possible logic in various embodiments of the present invention. [Figure 27] Figure 27 shows flowcharts of possible logic in various embodiments of the present invention. [Figure 28] Figure 28 shows flowcharts of possible logic in various embodiments of the present invention. [Figure 29] Figure 29 shows an embodiment of a sensing Foley catheter system with a loop controller in a patient environment. [Figure 30]Figure 30 shows an embodiment of a sensing Foley catheter system with a loop controller in a patient environment. [Figure 31] Figure 31 shows an embodiment of a sensing Foley catheter system with a loop controller in a patient environment. [Figure 32] Figure 32 shows an embodiment of a sensing Foley catheter system with a loop controller in a patient environment. [Figure 33] Figure 33 shows details of the loop controller with possible input parameters and output actions. [Figure 34] Figure 34 shows the plots of ultrasonic and pressure measurements of volume divergence. [Figure 35] Figure 35 shows the distal end of an embodiment of a sensing Foley catheter. [Figure 36] Figure 36 shows an embodiment of the filter inside the balloon. [Figure 37] Figure 37 shows an embodiment of a filter inside an inflated balloon. [Figure 38] Figure 38 shows an embodiment of the filter inside a deflated balloon. [Figure 39] Figure 39 shows an embodiment of the filter inside the balloon. [Figure 40] Figure 40 shows an embodiment of the filter inside the balloon. [Figure 41] Figure 41 shows an embodiment of the filter inside the balloon. [Figure 42] Figure 42 shows an embodiment of the filter inside the balloon. [Figure 43] Figure 43 shows an embodiment of the filter inside the balloon. [Figure 44] Figure 44 shows an embodiment of the filter inside the balloon. [Figure 45] Figure 45 shows an embodiment of the filter inside the balloon. [Figure 46] Figure 46 shows an embodiment of the filter inside the balloon. [Figure 47]Figure 47 shows an embodiment of a balloon equipped with multiple access lumens. [Figure 48] Figure 48 shows an embodiment of the balloon. [Figure 49] Figure 49 shows an embodiment of the balloon. [Figure 50] Figure 50 shows various embodiments of a balloon catheter equipped with a gas-permeable membrane. [Figure 51] Figure 51 shows various embodiments of a balloon catheter equipped with a gas-permeable membrane. [Figure 52] Figure 52 shows various embodiments of a balloon catheter equipped with a gas-permeable membrane. [Figure 53] Figure 53 shows various embodiments of a balloon catheter equipped with a gas-permeable membrane. [Figure 54] Figure 54 shows a controller for measuring gas content via a balloon catheter. [Figure 55] Figure 55 is a schematic diagram of the gas measurement catheter / controller system. [Figure 56] Figure 56 is a schematic diagram of the gas measurement catheter / controller system. [Figure 57A] Figure 57A shows an embodiment of the gas measurement add-on component. [Figure 57B] Figure 57B shows an embodiment of the gas measurement add-on component. [Figure 58A] Figure 58A shows a table listing parameter combinations that enable potential features for identifying acute kidney injury and UTIs based on patient parameters. [Figure 58B] Figure 58B shows a table listing parameter combinations that enable possible signs for identifying acute kidney injury, sepsis, and acute respiratory distress syndrome based on patient parameters. [Figure 59] Figure 59 shows the pressure characteristic curve inside the collection chamber during airlock clearance. [Figure 60]Figure 60 is a block diagram of a data processing system that can be used in any embodiment of the present invention. [Figure 61] Figure 61 shows alternative wavelengths that can be used to distinguish between red blood cells and / or plasma / white blood cells. [Figure 62] Figure 62 shows urine output data immediately after administration of a diuretic. [Figure 63A] Figure 63A shows how smaller diameter lumens can be compared to larger diameter lumens in the vent / filter region. [Figure 63B] Figure 63B shows how smaller diameter lumens can be compared to larger diameter lumens in the vent / filter region. [Figure 64] Figure 64 shows the curved barb region. [Figure 65] Figure 65 shows an embodiment of a sensing Foley catheter system equipped with a vent tube. [Figure 66] Figure 66 shows a sensing Foley catheter system with a separate positive pressure vent tube. [Figure 67] Figure 67 shows a magnified view of the barb region in Figure 66. [Figure 68] Figure 68 shows the barb regions of various embodiments of the sensing Foley catheter system. [Figure 69] Figure 69 shows the barb regions of various embodiments of the sensing Foley catheter system. [Figure 70] Figure 70 shows the barb regions of various embodiments of the sensing Foley catheter system. [Figure 71] Figure 71 shows the barb regions of various embodiments of the sensing Foley catheter system. [Figure 72] Figure 72 shows the barb regions of various embodiments of the sensing Foley catheter system. [Figure 73A] Figure 73A shows the barb regions of various embodiments of the sensing Foley catheter system. [Figure 73B]Figure 73B shows the barb regions of various embodiments of the sensing Foley catheter system. [Figure 74] Figure 74 shows the barb regions of various embodiments of the sensing Foley catheter system. [Figure 75A] Figure 75A shows the barb regions of various embodiments of the sensing Foley catheter system. [Figure 75B] Figure 75B shows the barb regions of various embodiments of the sensing Foley catheter system. [Figure 76] Figure 76 shows the barb regions of various embodiments of the sensing Foley catheter system. [Figure 77A] Figure 77A shows the barb regions of various embodiments of the sensing Foley catheter system. [Figure 77B] Figure 77B shows the barb regions of various embodiments of the sensing Foley catheter system. [Figure 78] Figure 78 shows the barb regions of various embodiments of the sensing Foley catheter system. [Figure 79] Figure 79 shows the barb regions of various embodiments of the sensing Foley catheter system. [Figure 80A] Figure 80A shows the barb regions of various embodiments of the sensing Foley catheter system. [Figure 80B] Figure 80B shows the barb regions of various embodiments of the sensing Foley catheter system. [Figure 81] Figure 81 shows the barb regions of various embodiments of the sensing Foley catheter system. [Figure 82A] Figure 82A shows the barb regions of various embodiments of the sensing Foley catheter system. [Figure 82B] Figure 82B shows the barb regions of various embodiments of the sensing Foley catheter system. [Figure 83]Figure 83 shows the barb regions of various embodiments of the sensing Foley catheter system. [Figure 84] Figure 84 shows the barb regions of various embodiments of the sensing Foley catheter system. [Figure 85] Figure 85 shows the barb regions of various embodiments of the sensing Foley catheter system. [Figure 86] Figure 86 shows the barb regions of various embodiments of the sensing Foley catheter system. [Figure 87] Figure 87 shows an embodiment of a sensing Foley catheter system equipped with an internal ventilation tube. [Figure 88] Figure 88 shows an embodiment of a sensing Foley catheter system equipped with an internal ventilation tube. [Figure 89] Figure 89 shows an embodiment of a sensing Foley catheter system equipped with an internal vent tube and a positive pressure tube. [Figure 90] Figure 90 shows an embodiment of a sensing Foley catheter system equipped with an internal ventilation tube. [Figure 91A] Figure 91A shows an embodiment of a sensing Foley catheter system equipped with an internal ventilation tube. [Figure 91B] Figure 91B shows an embodiment of a sensing Foley catheter system equipped with an internal ventilation tube. [Figure 92A] Figure 92A shows several embodiments of the drainage lumen. [Figure 92B] Figure 92B shows several embodiments of the drainage lumen. [Figure 93A] Figure 93A shows another embodiment of the drainage lumen. [Figure 93B] Figure 93B shows another embodiment of the drainage lumen. [Figure 93C] Figure 93C shows another embodiment of the drainage lumen. [Figure 93D] Figure 93D shows another embodiment of the drainage lumen. [Figure 93E]Figure 93E shows another embodiment of the drainage lumen. [Figure 94A] Figure 94A shows an embodiment of a sensing Foley catheter system in which the pressure sensor is located on a separate catheter. [Figure 94B] Figure 94B shows an embodiment of a sensing Foley catheter system in which the pressure sensor is located on a separate catheter. [Figure 94C] Figure 94C shows an embodiment of a sensing Foley catheter system in which a pressure sensor is located on a separate catheter. [Figure 95A] Figure 95A shows an embodiment of a sensing Foley catheter system equipped with a bubble reduction mechanism. [Figure 95B] Figure 95B shows an embodiment of a sensing Foley catheter system equipped with a bubble reduction mechanism. [Figure 95C] Figure 95C shows an embodiment of a sensing Foley catheter system equipped with a bubble reduction mechanism. [Figure 96A] Figure 96A shows an embodiment of a sensing Foley catheter system equipped with a bubble reduction mechanism. [Figure 96B] Figure 96B shows an embodiment of a sensing Foley catheter system equipped with a bubble reduction mechanism. [Figure 96C] Figure 96C shows an embodiment of a sensing Foley catheter system equipped with a bubble reduction mechanism. [Figure 96D] Figure 96D shows an embodiment of a sensing Foley catheter system equipped with a bubble reduction mechanism. [Figure 97A] Figure 97A shows an embodiment of a sensing Foley catheter system equipped with a bubble reduction mechanism. [Figure 97B] Figure 97B shows an embodiment of a sensing Foley catheter system equipped with a bubble reduction mechanism. [Figure 97C] Figure 97C shows an embodiment of a sensing Foley catheter system equipped with a bubble reduction mechanism. [Figure 97D]Figure 97D shows an embodiment of a sensing Foley catheter system equipped with a bubble reduction mechanism. [Figure 98A] Figure 98A shows an embodiment of a sensing Foley catheter system equipped with a bubble reduction mechanism. [Figure 98B] Figure 98B shows an embodiment of a sensing Foley catheter system equipped with a bubble reduction mechanism. [Figure 98C] Figure 98C shows an embodiment of a sensing Foley catheter system equipped with a bubble reduction mechanism. [Figure 98D] Figure 98D shows an embodiment of a sensing Foley catheter system equipped with a bubble reduction mechanism. [Figure 99A] Figure 99A shows an embodiment of a sensing Foley catheter system equipped with a bubble reduction mechanism. [Figure 99B] Figure 99B shows an embodiment of a sensing Foley catheter system equipped with a bubble reduction mechanism. [Figure 99C] Figure 99C shows an embodiment of a sensing Foley catheter system equipped with a bubble reduction mechanism. [Figure 100A] Figure 100A shows an embodiment of a sensing Foley catheter system equipped with a bubble reduction mechanism. [Figure 100B] Figure 100B shows an embodiment of a sensing Foley catheter system equipped with a bubble reduction mechanism. [Figure 100C] Figure 100C shows an embodiment of a sensing Foley catheter system equipped with a bubble reduction mechanism. [Figure 101A] Figure 101A shows an embodiment of a sensing Foley catheter system equipped with a bubble reduction mechanism. [Figure 101B] Figure 101B shows an embodiment of a sensing Foley catheter system equipped with a bubble reduction mechanism. [Figure 101C] Figure 101C shows an embodiment of a sensing Foley catheter system with a spiral channel in the collection reservoir. [Figure 101D]Figure 101D shows an embodiment of a sensing Foley catheter system with a spiral channel in the collection reservoir. [Figure 101E] Figure 101E shows an embodiment of a sensing Foley catheter system with a spiral channel in the collection reservoir. [Figure 102] Figure 102 shows the pressure waveform and its disappearance using a pressure balloon. [Figure 103] Figure 103 shows sample clinical data illustrating how to remove noise from cardiac signals using ECG. [Figure 104] Figure 104 shows sample clinical data illustrating stroke volume variability analysis using a model waveform. [Figure 105A] Figure 105A shows a diagram of the cassette-side component of an embodiment of a sealing mechanism for several lumens between the cassette and the controller / monitor. [Figure 105B] Figure 105B shows a diagram of the cassette-side component of an embodiment of a sealing mechanism for several lumens between the cassette and the controller / monitor. [Figure 106] Figure 106 shows the controller-side components of the embodiment of the sealing mechanism shown in Figures 105A and 105B. [Figure 107A] Figure 107A shows an embodiment of the lumen connection sealing mechanism between the cassette and the controller. [Figure 107B] Figure 107B shows an embodiment of the lumen connection sealing mechanism between the cassette and the controller. [Figure 108] Figure 108 shows an embodiment of the lumen connection sealing mechanism on the back of the cassette. [Figure 109] Figure 109 shows a cross-sectional view of the lumen connection sealing mechanism on the back of the cassette. [Figure 110] Figure 110 shows a dimensional view of the cassette-side component of an embodiment of a sealing mechanism for several tubular areas between the cassette and the controller / monitor. [Figure 111]Figure 111 shows a force view of the cassette-side component of an embodiment of a sealing mechanism for several lumens between the cassette and the controller / monitor. [Figure 112] Figure 112 shows an embodiment that includes a ventilation mechanism which can be added to any urine drainage system including a sampling port. [Figure 113] Figure 113 shows an embodiment including a pump / arger. [Figure 114] Figure 114 shows an embodiment in which the drainage tube is coiled or includes a compressed portion. [Figure 115A] Figure 115A shows an embodiment of the barb including a tube seating mechanism. [Figure 115B] Figure 115B shows an embodiment of the barb including a tube seating mechanism. [Modes for carrying out the invention]

[0029] Preferred embodiments of the present invention are described in detail herein. However, alternative embodiments of various features of the apparatus are also possible. Examples of these embodiments are provided below, but the scope of the invention is not limited to these specific configurations.

[0030] Sensing Foley Catheter

[0031] Figure 1 shows some embodiments and features of a sensing Foley catheter. The catheter can be understood to have various sections, depending on its position when inserted into a human subject, such as a proximal portion that remains outside the subject, a central portion that remains in the urethra, and a distal portion that remains in the urinary bladder.

[0032] Various internal lumens, such as air or fluid lumens communicating with the bladder retention balloon 104 and retention balloon port 118, traverse the length of the catheter. The urinary drainage lumen has a distal opening or opening 106 located inside, and has openings at the bladder portion of the catheter and the proximal end 114 of the catheter. The urinary drainage lumen may be connected to a urinary drainage tube that carries urine to a collection container. The urinary drainage tube may be separate from or integrated with the sensing Foley catheter. In some embodiments, the bladder drainage lumen and distal opening may also function as an infusion conduit from which drugs or heated or cooled fluids can be injected. A specimen sensor (not shown) or a temperature sensor (not shown) may be located in either the urethral portion of the catheter or the bladder portion of the catheter. Electrical or optical fiber conductors are located in the lumen to enable communication of detection signals between the distally located sensor and the proximal portion of the catheter, and then further communicate with a data processing device or controller.

[0033] An inflatable pressure-sensing balloon 108 (or a pressure-sensing membrane positioned across the opening) may be positioned at or near the distal end of the catheter. Embodiments of the pressure-sensing balloon or pressure-sensing membrane can be understood to have a pressure interface having a distally facing surface exposed to pressure from within the bladder and a proximal facing surface exposed to a 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 the pressure port 116 at or near the proximal end of the catheter. Embodiments of the fluid column (filled with either a liquid or gaseous fluid) may have a dedicated lumen or a shared lumen.

[0034] In some embodiments, the temperature sensor may be located at or near the distal end of the catheter. The temperature port 110 may include a temperature communication line 112 that connects the temperature sensor to a display, connector, and / or controller.

[0035] Figure 1 shows the proximal end of a catheter containing multiple separate ports, although some or all of the ports may be integrated into a single port or into a urine drainage line that goes to the urine drainage system and / or controller. Other lumens and / or ports may also be present.

[0036] Pressure-based physiological parameters that a sensing Foley catheter system can sense and / or determine via a controller based on sensed parameters may include, for example, abdominal pressure, respiratory rate, and heart rate, relative tidal volume profile, cardiac output, relative cardiac output, and absolute cardiac output. Some embodiments of the Foley catheter may further include a temperature sensor, one or more specimen sensors, electrodes, and a pair of light sources and sensors. Such further equipped embodiments can deliver other forms of physiological data, such as blood pressure, oxygen saturation, pulse oximetry, EKG, and capillary filling pressure.

[0037] Embodiments of a sensing Foley catheter may be able to sense any one or more of several clinically relevant parameters, such as those included in the following examples: urine pH, urine oxygen content, urine nitrate content, respiratory rate, heart rate, perfusion pressure of the bladder wall or urethral wall, temperature in the bladder or urethra, electrocardiogram via sensors on the bladder wall or urethra, respiratory volume, respiratory pressure, peritoneal pressure, urine glucose, blood glucose and / or bladder mucosa via the urethral mucosa, urine protein, urine hemoglobin, and blood pressure.

[0038] In some embodiments, the catheter may be able to sense multiple parameters, while in some embodiments, it may be limited to a single parameter for focused applications (e.g., respiratory rate in patients with respiratory distress).

[0039] The disclosed technology can capture a high-resolution time-series profile of intra-abdominal pressure from within the bladder (pressure as a function of time) and convert and process it into separate pressure profiles that can be assigned to specific physiological sources, including peritoneal pressure, respiratory rate, and heart rate. By tracking the pressure profile at a sufficiently fast sampling rate, as provided by the technology, the pressure profile can be further decomposed and / or analyzed into relative tidal volume, cardiac output, relative cardiac output, and absolute cardiac output.

[0040] Accordingly, aspects of the disclosed technology relate to the fidelity and resolution of pressure signals produced in response to changes in pressure within the bladder, where such changes reflect a pressure profile within the peritoneal cavity, and such a pressure profile includes cumulative input from the aforementioned physiological sources. A further aspect of this technology relates to the fidelity and resolution of the conversion of the pressure signals into highly decomposable electrical signals. A further aspect of the technology relates 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.

[0041] The sensitivity of an inflated balloon as a pressure sensor is, in part, a function of the pressure difference across the balloon membrane as a baseline condition. The balloon is most sensitive to pressure when the baseline pressure difference is close to zero. As the baseline pressure difference increases, the sensitivity of the pressure-sensitive balloon decreases. Therefore, the disclosed technology provides an automatic priming method that maintains the balloon in an inflated state but with a minimum pressure difference.

[0042] To effectively capture physiological pressure profiles, the profiles must be sampled at a rate sufficient to resolve the intrinsic frequency of changes in the profile. This consideration is noted by the Nyquist-Shannon sampling theorem, which states that to resolve an event occurring at a frequency of B cycles / second, a sampling rate of at least 2B samples / second is required. For example, when applied to physiological pressure cycles, a heart rate of 70 beats / min requires a sampling rate of at least 140 samples / min to effectively capture the cycle. This relationship forms the basis for aspects of disclosure techniques that specify the sampling rates particularly required to capture physiological pressure cycles, such as relative tidal volume, cardiac output, relative cardiac output, and absolute cardiac output.

[0043] Embodiments of this technology include a pressure interface that may be represented by a balloon having either an adaptive or non-adaptive membrane.

[0044] The expandable pressure-sensing balloon according to embodiments of this technology may be one or more of at least two basic forms, adaptable or non-adaptive. In the adaptable balloon type, which can generally be likened to a conventional party balloon, the pressure-sensing balloon is formed from or contains an adaptable membrane. Thus, the surface area of ​​the membrane expands or contracts as a function of the balloon's inflation. The adaptability of the membrane determines the various functions of the balloon as a whole at different levels of inflation. When inflated, the balloon maintains a substantially constant or preferred shape or form, as determined by the mandrel on which the balloon is formed, if it is not constrained. As the balloon inflates from a minimum volume to a maximum volume, the balloon's membrane maintains tension. Within the adaptability range of the adaptable membrane, the volume expands as the pressure increases during inflation. While the balloon as a whole may be considered partially adapted in that its shape accommodates the spatial constraints it may encounter during expansion or inflation, the balloon has a preferred or native shape, and the preference of such a shape prevents the level of adaptability as demonstrated by shape-adaptive or non-adaptive balloons.

[0045] In non-adaptive balloons, the expandable pressure-sensing balloon is formed from or contains an inelastic membrane, or a substantially inelastic membrane. Therefore, the surface area of ​​the membrane does not expand or contract in response to the balloon's inflation / pressure level. Non-adaptive pressure-sensing balloons are generally likened to conventional Mylar® balloons. The lack of membrane adaptability, as a whole, determines the various characteristics of the balloon at different levels of inflation. When the balloon expands from its minimum volume to near its maximum volume, the balloon membrane is supple and has some slack. Inflation of a non-adaptive balloon occurs by smoothing out wrinkles and folds in the membrane. Contraction or compression of a non-adaptive balloon generally occurs by inward-facing wrinkles and folds. When a non-adaptive balloon fully inflates (or substantially inflates) without entering a confinement space, a preferred or natural shape determined by the shape of the balloon's membrane or fabric is assumed. However, when partially inflated, the balloon as a whole is very flexible and adaptable, and can take on a wide range of shapes dictated by the enclosed space.

[0046] An expandable pressure-sensing balloon according to an embodiment of the technology may also include features of both two basic forms: adaptable and non-adaptive. In these embodiments, the membrane may include adaptable and non-adaptive regions. This hybrid type of balloon, as a whole, operates in a manner that draws from both the working surfaces of the adaptable and non-adaptive balloons, as described above. Furthermore, the adaptable balloon may be formed of a membrane that is not uniform in composition or thickness. In such embodiments, regions of different thicknesses or compositions may have varying degrees of adaptability and thus affect the behavior of these regions during balloon expansion. In yet another embodiment, the adaptability of the membrane may have a bias or polarity that tends to allow adaptability in one or more directions and prohibit adaptability in one or more other directions.

[0047] An expandable pressure-sensing balloon according to an embodiment of the technology may also include features of both two basic forms: adaptable and non-adaptive. In these embodiments, the membrane may include adaptable and non-adaptive regions. This hybrid type of balloon, as a whole, operates in a manner that draws from both the working surfaces of the adaptable and non-adaptive balloons, as described above. Furthermore, the adaptable balloon may be formed of a membrane that is not uniform in composition or thickness. In such embodiments, regions of different thicknesses or compositions may have varying degrees of adaptability and thus affect the behavior of these regions during balloon expansion. In yet another embodiment, the adaptability of the membrane may have a bias or polarity that tends to allow adaptability in one or more directions and prohibit adaptability in one or more other directions.

[0048] These data demonstrate the suitability of using an embodiment of the pressure conversion system in small-diameter pediatric catheters down to a small size of 4F. In this embodiment as well, the tip of the catheter may have a lower profile than the rest of the catheter to allow for consistently small diameters even with the addition of a pressure-sensing balloon. Thus, the catheter of the present invention is uniquely suited to pediatric indications where a more appropriate and less invasive monitoring method is urgently needed. In another embodiment, the retaining balloon itself can be used as the pressure balloon to minimize the number of lumens required. In one embodiment, the retaining balloon is used fully inflated and only for tracking macro trends in IAP. In another embodiment, the retaining balloon is slightly inflated to increase the balloon's sensitivity to small changes in pressure. This embodiment allows for finer measurements of microparameters such as heart rate, relative stroke volume, relative cardiac output, respiratory rate, and relative tidal volume. Also, reducing the pressure lumen makes space for larger catheters for other technologies such as sensors.

[0049] In embodiments of a sensing Foley catheter where a retaining balloon is used as a pressure balloon, the pressure measured within the retaining balloon is offset by the pressure required to inflate the balloon sufficiently to function as a retaining balloon. Consequently, the inflation pressure, and potentially the pressure arising from the retaining balloon in contact with the bladder lining, must be subtracted from the pressure measurement. In this way, small pressure changes can be tracked as well as those measured with individual pressure balloons. The inflation pressure offset can be determined by measuring the pressure within the retaining balloon when it is first inserted into the patient, by measuring the inflation pressure of the retaining balloon outside the patient, or by other means. The retaining balloon may be filled with fluid, air, or other suitable gas.

[0050] Embodiments of the disclosed technology may include embodiments in which the pressure sensor is a mechanical pressure sensor, such as one using optical fiber, strain gauge, magnetic, resonant, and / or other suitable techniques.

[0051] Figure 2 shows an example of respiratory rate sensing data from a subject provided by an embodiment of the sensing Foley catheter system. During this test period, the subject performs the following respiratory sequence: (1) exhalation at the end of exhalation, (2) Valsalva maneuver, (3) hyperventilation, (4) Valsalva maneuver, and (5) exhalation at the end of inspiration.

[0052] Figure 3 shows a detailed portion of a normal respiratory cycle in a respiratory profile similar to that shown in Figure 2. The pressure curve clearly indicates the respiratory peak, allowing for the determination of the respiratory rate and heart rate peaks. Therefore, the heart rate can be determined.

[0053] Figure 4 shows an example of heart rate and relative cardiac output sensing data from a subject, as well as an EKG trace measured simultaneously and independently, provided by an embodiment of the sensing Foley catheter system. This graph clearly shows that the peak heart rate measured by the sensing Foley catheter coincides with the actual heart rate.

[0054] Figure 5 shows data related to relative cardiac output sensing during human leg-raising exercise, which increases cardiac output as demonstrated by the increased amplitude of the heartbeat.

[0055] Figures 6 and 7 are derived from studies conducted using Yorkshire pigs under a protocol approved by the IACUC. Figure 6 shows an example of peritoneal sensing data focused on respiratory rate from pigs, provided by an embodiment of the sensing Foley catheter system. Figure 7 shows an example of a pig study demonstrating the ability of an embodiment of the sensing Foley catheter system to detect intraperitoneal hypertension. In this study, the peritoneal cavity was accessed with a 5 mm tenamian trocar. The trocar was then attached to a 5 L bag of Ringer's lactate solution via a peristaltic pump, and the solution was injected at a rate of approximately 1 L per minute. After a pressure of approximately 20 mmHg was achieved, the fluid flow was interrupted, and thereafter, there was no net fluid flow in or out of the cavity.

[0056] Figure 8 shows intraperitoneal pressure, respiratory wave pressure, and cardiac pressure schematically arranged as a two-dimensional plot of pressure (mmHg on a logarithmic scale) versus frequency (Hz). There is an inverse relationship between pressure and frequency, and when arranged in this manner, it can be seen that various physiological pressure-related parameters occupy different sectors. The clarity of both these pressure and / or frequency profiles allows embodiments of the method disclosed herein to decompose a single overall temporal pressure profile into distinct subprofiles, depending on their physiological origin. Intraperitoneal pressure measurements can be resolved in the frequency range of approximately 0 Hz to approximately 0.5 Hz. Respiratory pressure measurements can be resolved in the frequency range of approximately 0.25 Hz to approximately 0.75 Hz. Cardiac pressure measurements can be resolved in the frequency range of approximately 0.75 Hz to approximately 3.0 Hz. Intraperitoneal pressure measurements can be resolved in the amplitude range of approximately 5 mmHg to approximately 30 mmHg. Respiratory pressure measurements can be resolved in the amplitude range of approximately 0.5 mmHg to approximately 5 mmHg. Cardiac pressure measurements can sometimes be resolved within an amplitude range of approximately 0 mmHg to 0.5 mmHg. The sampling frequency (the frequency at which pressure measurements are taken) should ideally be approximately twice the resolution frequency. For example, the sampling frequency is approximately 0 Hz-1 Hz for intra-abdominal pressure measurements, 0.5 Hz-1.5 Hz for respiratory pressure measurements, and 1.5 Hz-6 Hz for cardiac pressure measurements.

[0057] Figure 9 provides a flowchart of an embodiment of a method for monitoring pressures that dynamically occur in the abdominal cavity as waves of various frequencies and amplitudes, detected from within the bladder. Through the pressure interface engine, a high-fidelity pressure profile is produced and transmitted proximal to the fluid column. More proximal, a pressure transducer converts the high-fidelity pressure waves into high-fidelity electrical signals that provide information on pressure frequency and amplitude. The produced high-fidelity electrical signals are processed by a controller to generate a data subset that reflects components in the overall pressure profile attributable to specific physiological sources such as abdominal pressure, respiratory rate, heart rate, relative cardiac output, and patient exercise or activity.

[0058] Sensing Foley Catheter System

[0059] Figure 10A shows an embodiment of a sensing Foley catheter used in conjunction with an embodiment of an airlock cleaning mechanism and a fluid collection and analysis system. Both urine discharge and pressure measurements benefit from the removal or reduction of airlocks in the urine discharge line.

[0060] Sensing Foley catheter 1000 is similar to the sensing Foley catheter shown in Figure 1. Sensing Foley catheter is shown in use in bladder 1014. Several ports at the proximal end of the catheter shown in Figure 1 are similar to the embodiment shown in Figure 10A. A urinary drainage tube 1001 is also shown here. The urinary drainage tube may be combined with the sensing Foley catheter or be a separate component. The urinary drainage tube 1001 and / or the sensing Foley catheter may also include a vent barb (or barb) 1016, or the vent barb may be a separate component. An airlock cleaning mechanism and fluid collection and analysis system 1002 is also shown here, and is in fluid communication with the urinary drainage tube 1001 which is in fluid communication with the sensing Foley catheter 1000. The airlock cleaning mechanism and fluid collection and analysis system includes a base / controller 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 cleaning mechanism and fluid collection and analysis system 1002 is also referred to herein as the sensing Foley catheter system. The sensing Foley catheter, urinary drainage line, and reservoir / cassette are disposable and can be sold as a unit. This disposable assembly is shown in Figure 10D and includes the sensing Foley catheter 1000, the urinary drainage tube 1001 (including the vent barb), and the reservoir / cassette 1022.

[0061] The vent barb 1016 may include one or more vents 1006 and a urine sampling port 1004. In this embodiment, the vent 1006 is preferably made of a membrane that allows the permeation of gases rather than liquids, such as a hydrophobic membrane. Examples of such exemplary vents include PTFE (polytetrafluoroethylene), ePTFE (expanded PTFE), or Versapor® (POLL Corporation, Port Washington, New York) membranes, but other materials may be used. The vent allows air to enter the system when negative pressure is applied to the drainage tube, and air to exit the system when positive pressure is generated by the airlock in the drainage line. Such a mechanism prevents, for example, aspiration trauma to the bladder wall. The vent 1006 may incorporate a one-way valve to prevent air from exiting or entering the drainage line. In a preferred embodiment, a one-way valve is used to prevent air from leaving the drainage line but to allow air to enter the drainage line through the vent 1006. In this way, the valve also prevents urine from coming into contact with the vent 1006.

[0062] The urinary drainage tube 1001 may include several lumens, including a pressure lumen 1010, a temperature lumen 1008, and a ureteral lumen 1012. The pressure lumen 1010 is in fluid communication with a pressure-sensing balloon 108 and a pressure transducer interface 1026 in the controller 1018. The Foley catheter has a temperature sensor (not shown), and the controller has a temperature connector 1024. The ureteral lumen 1012 is in fluid communication with one or more openings 106 and a urinary reservoir or cassette 1022.

[0063] The disposable measuring container, collection container, chamber, or cassette component 1022 is housed in a cassette mount, base, or controller 1018 and is designed to work in conjunction with the controller's components. The controller cassette interface (behind the cassette pump interface 1148) connects to the pump 1134 and the cassette pump interface 1148 on the disposable cassette component. The pump is designed to produce a vacuum inside the cassette component, which is then delivered to the urinary drainage lumen of the drainage line. Preferably, the collection container / cassette is rigid to maintain a constant volume when the pump applies negative pressure. The level of negative pressure applied can be monitored by a pressure sensor. During airlock clearance, the pressure follows a characteristic curve as shown in Figure 59. As suction is applied, the pressure decreases and eventually reaches an inflection point as the meniscus of urine passes the lowest point in the drainage tube. At this point, since only a small amount of suction is needed to continue clearing the airlock, the pump output can be reduced to minimize the amount of suction delivered to the bladder once the airlock is completely cleared. For example, large vessels lacking this pressure sensing capability transmit a substantial negative pressure to the bladder before the airlock is released and equilibrium with the atmosphere. The controller pressure interface (behind the cassette pressure interface 1150) connects to the cassette pressure interface 1150 with pressure measuring devices such as pressure transducers. The pressure measuring devices are designed to measure the volume of urine or other fluids based on the pressure applied to the pressure measuring device, such as a pressure transducer. The ultrasonic transducer interface 1130 is also to provide urine volume measurement. Ultrasonic measurement can be used in combination with pressure measurement, or to determine the volume output of urine or other fluids. The active pinch valve 1132 is designed to connect to the cassette's outflow tube. The pinch valve is for controlling the emptying of the cassette container, and is controlled by the controller to release urine / fluid when the urine output reaches a certain volume in the cassette, as determined by pressure and / or ultrasonic measurement.The amount of urine in the cassette is measured, and when the urine reaches a certain amount, it is discharged into the urine drainage bag 1020 via a pinch valve. For example, when the amount of urine in the cassette reaches approximately 50 mL, the cassette is emptied. Alternatively, the cassette can be emptied when the amount of urine reaches approximately 40 mL. Alternatively, the cassette can be emptied when the amount of urine reaches approximately 30 mL. Alternatively, the cassette can be emptied when the amount of urine reaches approximately 20 mL. Alternatively, the cassette can be emptied when the amount of urine reaches approximately 10 mL. In this way, the amount of urine discharged can be accurately measured over time.

[0064] Emptying a cassette can be enhanced or accelerated by pressurizing the cassette during the emptying process.

[0065] Alternatively, the controller may use a set time while emptying the cassette to measure the amount of urine in the cassette just before emptying. Or, the controller may empty the cassette when a vent occurs, such as when an airlock is removed, triggered by the pump starting up. For example, the controller may set up a periodic airlock clearance cycle, measure the amount of urine in the cassette afterward, and then empty the cassette.

[0066] For example, the controller can control the pinch valve to empty the reservoir / cassette when the urine volume reaches approximately 50 mL. Alternatively, the controller can control the pinch valve to empty the reservoir / cassette every hour after measuring the urine volume in the cassette. Alternatively, the controller can control the pinch valve to empty the reservoir / cassette during or after the urine drainage vent, such as when the pump is running. Alternatively, the controller can use a combination of these triggers to control the pinch valve and empty the reservoir / cassette.

[0067] Other techniques may be used to measure urine volume in addition to, or instead of, pressure and / or ultrasound, including pressure-based, resistance-based, capacitance-based, ultrasound-based, or optical-based techniques. Multiple techniques can be used to compare measurements with each other and improve the accuracy of volume measurement. To obtain more accurate urine volume measurements, multiple volume measurements performed by one or more techniques can be used redundantly, as backups, or in combination with each other.

[0068] The bed hook 1116 is for hooking the controller to a bed or other device as needed. It can also be used to hook the controller to a portable device for patient transport. The collection bag hook / hole 1102 is for attaching a drainage bag into which urine / fluid is ultimately collected after it has passed through the pinch valve. The collection bag hook 1102 may be designed to provide a strain measurement so that the weight of the fluid in the bag can be determined, and thus provide another method for determining the volume of the fluid in the bag. For example, a piezoelectric transducer may be used. The controller may also use a specific gravity determination to determine a useful volume measurement based on weight and specific gravity.

[0069] Screen 1110 is for displaying information including the current urine / fluid volume status and system status. Screen 1110 is also a touchscreen and can receive input including settings, screen display changes, and menu changes. Pressure port 1026 connects to the bladder pressure line 1010 and, 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 on the controller / base. Temperature port 1024 connects to a thermistor / temperature sensor that measures body temperature via a sensing Foley catheter or other means through the lumen 1008. Temperature output port 1122 is for transmitting temperature measurements to an external device and / or monitor. Adapter port 1124 is for adapting the controller to other devices, such as an RFID adapter. This can be used to activate additional / advanced functions, such as measuring IAP, respiratory rate, heart rate, cardiac output, or other parameters that can be measured by a sensing Foley catheter. This allows additional parameters to be enabled and paid for at the hospital only when that information is needed. The activation of advanced features can also be controlled, for example, by the use of different disposable components. Alternatively, advanced features can be enabled as part of the disposable functionality or through separately purchased software upgrades. Software upgrades are provided wirelessly, via USB dongles, micro-SD cards, EPROM cards, or other appropriate technologies. Individual patient and / or aggregated patient data may also be stored by the controller. Patient data can be stored in memory, USB, micro-SD cards, EPROM cards, hard drives, etc. Patient data can be transferred wirelessly or via wired connections to other storage devices, such as servers on the internet or intranet. Patient data may be anonymized. Patient data, such as patient IDs, is stored in the RFID adapter so that data specific to a particular patient is recognized by the controller and associated with the disposable components used by that patient.

[0070] The power LED / indicator 1114 indicates whether the power is on or off. The error LED / indicator 1112 is an indicator of an error occurring in the system. While details of the error can be displayed on screen 1110, indicator 1112 warns the user that an error exists. The indicator may also incorporate sound or other warnings.

[0071] Port 1108 is used for downloading, uploading, software upgrades, and connecting to other devices, including integration with EMR (Electronic Medical Records) systems. Port 1108 is a USB port or other suitable port. SD port 1106 is for data downloads. Power port 1104 is for supplying power to the controller by connecting it to a wall or other power source.

[0072] The urine / fluid drainage bag 1020 includes a one-way valve 1136 connected to an overflow tube 1138 and an outlet tubing 1140, preventing urine / fluid from leaving the drainage bag once collected. These valves prevent air from entering the collection container 1022 when the pump 1134 is drawing a vacuum, ensuring that the vacuum acts on the drainage tube rather than the bag. In a preferred embodiment, a single valve is used for both the overflow and outlet tubes. Mounting hooks / holes 1102 allow the drainage bag 1020 to be detachably mounted to the controller 1018. The vents 1142 are hydrophobic or other vents that allow air or gas to exit the drainage bag, but not fluid. This prevents excess air and potentially pressure from accumulating in the bag, thus enabling efficient filling of the drainage bag. Graduated marks 1144 indicate a somewhat rough measurement of the amount of fluid in the bag as the bag is collected. The fluid / urine bag can be emptied using the outflow valve 1146. Preferably, the valve is easily operated by one person. The collection bag hook 1102, designed as a strain measuring element, can also sound an alarm when the bag has reached full capacity and needs to be emptied. The alarm may also sound if unnecessary excessive force is applied to the bag, for example, if the bag is pulled or gets caught on an obstacle during patient movement.

[0073] The patient's body temperature is measured using a thermistor / temperature sensor inside the patient's body. This temperature passes through a controller and may be displayed on a third-party device. Figure 10B shows how parallel potentiometers are used to reduce temperature measurement errors before the temperature measurement is transmitted to an external display or external device.

[0074] The drainage bag may be made of clear vinyl or other suitable material. The one-way valve may be made of vinyl or other suitable material. The hydrophobic vent may be made of ePTFE, Versapor, or other suitable material. The outlet valve may be made of PVC, PC, or other suitable material.

[0075] The pressure readings from the sensing Foley catheter can be used to activate a pump, thereby emptying the drainage tube. For example, if the pressure sensed in the bladder exceeds a preset number, the pump can be activated to move urine more quickly through the drainage tube.

[0076] The controller / base and / or reservoir / cassette may include an accelerometer or other sensor to determine when the controller / cassette is horizontal or not. An alarm may sound if the controller / cassette is not horizontal. Alternatively, the urine volume measurement may be adjusted to account for various angles within the system.

[0077] The bottom of the urine reservoir inside the cassette has a rounded edge, or it is configured so that the urine completely empties from the cassette when the pinch valve opens.

[0078] Figure 10C is a detailed view of the airlock clearing mechanism and fluid collection and analysis system 1002. Screen 1110 displays a user interface including patient parameters and a touchscreen or other control functions. The heart rate area 1152 shows the patient's heart rate, determined by the controller based on bladder pressure measurements detected by a sensing Foley catheter. The respiratory rate area 1154 shows the patient's respiratory rate, determined by the controller based on bladder pressure measurements detected by the Foley catheter. The core body temperature area 1156 shows the patient's core body temperature, detected by a temperature sensor on the Foley catheter or the like. The urine output area 1158 shows the patient's current and / or average urine output, determined by the controller based on urine volume measurements measured by a pressure measuring device connected to the pressure interface 1150 and / or ultrasonic transducer interface 1130. The sepsis index area 1160 indicates the patient's likelihood of sepsis, determined by the controller based on one or more collected and / or calculated patient parameters. For example, when assessing the risk of sepsis, factors such as body temperature, abnormal heart rate, abnormal respiratory rate, and / or urine output can be considered. Trends in these parameters can also be used to assess risk. For instance, decreased urine output, increased heart rate, and changes in core body temperature may be indicators of sepsis.

[0079] Other risk assessments are determined by the controller and may be presented in addition to or as an alternative to the sepsis index. These include risk assessments for acute kidney injury, urinary tract infection, intra-abdominal hypertension, abdominal compartment syndrome, infection risk, sepsis, and ARDS (acute respiratory distress syndrome). For example, the sample risk algorithms for acute kidney injury and urinary tract infection are shown in Figure 58A. The sample risk algorithms for acute kidney injury, sepsis, and acute respiratory distress syndrome are shown in Figure 58B. Urine parameters measured may include conductance, specific gravity, urine output, presence or absence of infection, bacteria, leukocytes, and oxygen partial pressure.

[0080] The graphical indicator 1162 displays historical data for these areas. For example, the user may be able to switch the graphic display by touching the screen to show patient history or other relevant parameters such as patient urine output, body temperature, heart rate, respiratory rate, sepsis index, risk of acute kidney injury, urinary tract infection, intra-abdominal hypertension, abdominal compartment syndrome, and infection risk. The historical time frame can be all time, daily, hourly, or a user-defined period. Any risk factors that are outside the range and therefore have a high risk may be automatically displayed here or elsewhere on the display. Alerts and / or ranges can be user-defined and may include absolute values ​​or long-term trends. For example, if core body temperature rises by more than 2 degrees Celsius within a specific time frame, a visual or audio alert may be displayed.

[0081] Figure 11A shows an embodiment of a sensing Foley catheter system (including an airlock clearing mechanism, fluid discharge, collection, and analysis system / controller) similar to that shown in Figure 10A, where the vent 1180 is located in the controller 1018 or the reservoir / cassette 1022. In this embodiment, the vent 1180 is in fluid communication with the urinary drainage lumen 1012 via the vent 1184, and the vent lumen 1184 is fluidly connected to the ureteral lumen 1012 at the vent 1184. In this embodiment, the barb design is simplified, and the drainage tube simply has an additional lumen compared to the embodiment shown in Figure 10A. The vent can be located anywhere in the system, and the fluid interface with the ureteral lumen can also be located anywhere in the system.

[0082] Figure 11B shows an embodiment of a sensing Foley catheter system similar to that shown in Figure 11A. In this embodiment, a gas-permeable vent / filter is incorporated into the cassette 1022 and / or controller 1018. The vent lumen can pass through the drainage tube 1012, from the barb 1182 into the vent tube 1184. The vent lumen may terminate outside the cassette and / or controller, or, as shown here, pass through the cassette and optionally the controller to incorporate the gas-permeable vent / filter 1180. Figure 11B also shows a valve 1186. The valve may be a one-way valve that allows a flow of fluid (e.g., air) through the vent lumen and through the barb into the drainage tube, or elsewhere along the drainage tube or Foley catheter, or into the base / controller 1018. The valve prevents liquids such as urine or air from flowing through the vent tube and reaching the filter. The valve may be passive as shown here, or it may be actively controlled by the controller. The valve may be anywhere within or along the vent lumen, such as within the barb, along the vent, within the cassette, within the controller, or outside the controller, for example, on the non-patient side of the controller.

[0083] In some embodiments, the valve is actively controlled via a controller by controlling the negative pressure within the drainage tube. The valve can be opened by a controller that reduces the negative pressure in the drainage lumen of the drainage tube, and the valve can be closed by a controller that reduces the vacuum applied to the drainage tube (i.e., by reducing the negative pressure to zero or applying a slight positive pressure to the drainage lumen). Since the drainage lumen of the catheter and drainage tube are in fluid communication with the lumen of the ventilator, the negative pressure applied to the drainage tube is also applied to the lumen of the ventilator, and the valve opens when the pressure difference across the valve exceeds the valve's cracking pressure. By reducing the vacuum applied to the drainage lumen, the valve is closed again, and thus the pressure difference across the valve is reduced to a pressure below the valve's cracking pressure. In this way, the controller can actively control the opening and closing of the valve in the ventilator, even if the valve itself is a passive valve.

[0084] In some embodiments, the controller that actively opens the valve may perform this action periodically, for example, on a regular schedule. This is illustrated graphically in Figure 11F. For example, the controller may open the valve at least every 30 minutes (represented by T1), keep it open for at least 15 seconds (represented by T2), and then close the valve for another 30 minutes until the cycle starts 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 figure. DIFF is greater than the valve cracking pressure difference. 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.

[0085] Figure 11F shows the valve closure pressure under negative pressure, but the valve closure pressure can be zero or positive.

[0086] Alternatively, the cycle length may be variable, and T1 and / or T2 depend on the urine discharge flow rate. Alternatively, this cycle may be based on a system that detects an airlock in the drainage tube. This can be done by measuring the pressure in the system, for example, the vacuum pressure in the drainage tube or the pressure of the barb.

[0087] In some embodiments, the valve 1186 may be in a predetermined position without the filter 1180. In some embodiments, the filter 1180 may be located between the drainage lumen and the valve 1186.

[0088] In some embodiments, the vent pipe 1184 is integrated with the drain tube 1012 along all or part of the length of the drain tube.

[0089] The valve may be a duckbill valve, umbrella valve, ball valve, dome valve, Belleville valve, cross-slit valve, X-Fragm valve, or other valve suitable for medical applications. The valve cracking pressure can be very low or high, but is typically between zero and the magnitude of the negative pressure drawn by a vacuum pump.

[0090] Figure 11C shows an embodiment of a sensing Foley catheter system similar to that shown in Figure 11B. In this embodiment, the vent canal includes a portion of the lumen with a smaller diameter between the barb and the valve. The tube with the smaller inner diameter 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 canal when the vent valve is closed. When the vent valve is open, the fluid flow generally flows in the reverse direction (i.e., into the drainage lumen), preventing urine from entering the vent canal.

[0091] Figure 11D shows an example of a vent tube with compartments of different diameters. The first compartment 1188 is the compartment closest to the patient and has an internal ID of ID1 and a length of L1. In this embodiment, valve 1186 allows fluid to flow generally only from right to left, as indicated by the dashed arrow. The second compartment 1190 is further away from the patient and has an internal ID of ID2 and a length of L2. In some embodiments, L1 is less than L2 and ID1 is less than ID2. In some embodiments, ID1 is smaller than ID2, but the lengths may vary or be the same as each other. L1 + L2 is approximately the same length as the drainage tube.

[0092] In some embodiments, ID1 may be about 1.8 to 2.0 mm. In some embodiments, ID1 may be about 1.6 to 1.8 mm. In some embodiments, ID1 may be about 1.4 to 1.6 mm. In some embodiments, ID1 may be about 1.2 to 1.4 mm. In some embodiments, ID1 may be about 1.0 to 1.2 mm. In some embodiments, ID1 may be about 0.8 to 1.0 mm. In some embodiments, ID1 may be about 0.5 to 0.8 mm. In some embodiments, ID1 may be about 0.2 to 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 over all or part of its length.

[0093] In some embodiments, ID2 may be about 1.8 to 2.0 mm. In some embodiments, ID2 may be about 1.6 to 1.8 mm. In some embodiments, ID2 may be about 1.4 to 1.6 mm. In some embodiments, ID2 may be about 1.2 to 1.4 mm. In some embodiments, ID2 may be about 1.0 to 1.2 mm. In some embodiments, ID2 may be about 0.8 to 1.0 mm. In some embodiments, ID2 may be about 0.5 to 0.8 mm. In some embodiments, ID2 may be about 0.2 to 5 mm. In some embodiments, ID2 may be less than about 4 mm. In some embodiments, ID2 may be less than about 5 mm. In some embodiments, ID2 may be less than about 6 mm. In some embodiments, ID2 may be greater than about 2 mm. In some embodiments, ID2 may be greater than about 5 mm. In some embodiments, ID2 may be greater than about 6 mm.

[0094] In some embodiments, L1 may be less than approximately 5 cm. In some embodiments, L1 may be less than approximately 10 cm. In some embodiments, L1 may be approximately 5 to 10 cm. In some embodiments, L1 may be approximately 10 to 20 cm. In some embodiments, L1 may be approximately 20 to 30 cm. In some embodiments, L1 may be approximately 30 to 50 cm. In some embodiments, L1 may be greater than approximately 50 cm. In some embodiments, L1 may be greater than approximately 1 cm. In some embodiments, L1 may be greater than approximately 2 cm. In some embodiments, L1 may be greater than approximately 5 cm. In some embodiments, L1 may be greater than approximately 10 cm.

[0095] In some embodiments, L2 may be approximately 50-150 cm.

[0096] In some embodiments, ID1 and ID2 may be the same.

[0097] Figure 11E shows an embodiment of a catheter system in which a vent lumen 1184 is in direct fluid communication with a fluid collection bag 1020. In this embodiment, a controller including a sensing function may or may not be present. In this embodiment, airlock is avoided by a vent lumen that vents the urinary drainage lumen 1012 using a vent hole 1142 in the fluid collection bag. The vent hole may be additionally or alternatively located anywhere along the vent lumen. The vent lumen may extend for part or all of the length of the drainage lumen. The urinary drainage lumen fluidly connects 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. In this embodiment, and potentially in other embodiments, the fluid collection bag 1020 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 the valve 1186. The vent tube 1184 may be incorporated into the drainage tube system or may be an additional component connected at the connection point 1194 between the barb of the Foley catheter and the drainage bag.

[0098] Figure 12A shows an embodiment of a sensing Foley catheter system similar to that shown in Figure 10A, but without a pressure balloon, in contrast to the system shown in Figure 10A. Instead, pressure is measured in the bladder via the ureteral lumen (or other lumen) of the sensing Foley catheter. In this embodiment, the pressure lumen 1202 is connected to a vent 1204 or another location in the system outside the patient and is in fluid communication with the catheter's drainage / ureteral lumen at least periodically. In this embodiment, the sensing Foley catheter system may be used with any standard Foley catheter. Any embodiment of the sensing Foley catheter system can be used with a standard Foley catheter. The system shown in Figure 12 may be used with a standard Foley catheter without the pressure lumen 1202 if measuring pressure in the bladder is undesirable.

[0099] Figure 12B shows an embodiment of a sensing Foley catheter system that does not include IAP or temperature measurement. This embodiment still retains an airlock prevention function.

[0100] Figure 13 shows an embodiment of a sensing Foley catheter system similar to that shown in Figure 12. In this embodiment, a valve 1302 can be used to periodically close the pressure lumen 1202 to the urinary drainage lumen. The valve can be opened by the controller or manually when pressure measurement is performed and closed again by the controller or manually when bladder pressure readings are no longer needed.

[0101] Figures 10A, 10C, 11, and 12 show embodiments of a sensing Foley catheter system that include a vent near the patient end of the drainage tube to allow air to enter the drainage tube if negative pressure is generated due to either or both of the siphon and / or pump mechanism within the drainage tube. Without a vent / filter, such negative pressure could lead to aspiration trauma, such as trauma caused to the inner mucosal layer of the bladder. Note that these embodiments differ from devices in which the vent allows air to be expelled but not enter the drainage tube.

[0102] The urinary drainage lumen preferably has an inner diameter of less than approximately 0.25 inches so that the fluid within the lumen maintains circumferential contact with the lumen, forming a seal and allowing the fluid to advance when the pump mechanism is activated. Multiple drainage lumen may be present to prevent blockage of the flow in the event of pump mechanism failure. In these embodiments, the drainage lumen is preferably generally empty, which may require continuous operation of the pump mechanism. Alternatively, the pump mechanism can be activated before volume measurement to ensure that all fluid has been drained, thereby reducing the power required by the device.

[0103] Some embodiments of sensing Foley catheter systems involve detecting pressure spikes in a drainage line while the pressure within a body organ remains constant, and using a pump to create negative pressure through the drainage line until the pressure in the drainage line equals the pressure in the body organ.

[0104] In one embodiment, the vent has resistance to airflow greater than the resistance to fluid flow from the patient, so that any fluid buildup in the patient is purged into the drainage line before air enters through the vent. For example, in the case of urine drainage, as long as the resistance to airflow through the vent is greater than the resistance to urine flowing through the patient's catheter, the entire bladder will be drained into the drainage line before air enters through the vent. However, to minimize aspiration trauma, it is preferable that the vent has as little resistance to airflow as possible while still meeting this requirement.

[0105] In another embodiment, the vents offer very little resistance to airflow, further protecting the bladder from aspiration, and the controller pump prevents urine from entering the drainage line at more frequent intervals, e.g., every minute, every five minutes, or every ten minutes. Once the pump is activated, it continues to operate until it detects that no more urine is being expelled, indicating that the bladder is completely empty. Alternatively, the pump may operate for a set period, such as approximately 30 seconds, 1 minute, 3 minutes, 5 minutes, or 10 minutes. The controller pump may be inactive between intervals or produce a "background vacuum" (negative pressure lower than the airlock clearance pressure) between airlock clearance intervals.

[0106] The pumping mechanism used may include, but is not limited to, a peristaltic pump, diaphragm pump, vane pump, impeller pump, centrifugal pump, or other suitable pump. The pump is powered by a wall outlet, battery, manual labor, or other suitable power source. In some embodiments, the vacuum is in the range of approximately 0 to -50 mmHg. Alternatively, the negative pressure may be supplied by the vacuum of the walls, which is often present in hospital rooms. The pumping mechanism may include a peristaltic-like pump or suction applied directly to the collection container. The pump may be located on the patient side of the drainage reservoir, or, preferably, on the non-patient side of the drainage reservoir / cassette, with the reservoir between the patient and the pump. For proper functioning, it is desirable that the pump be able to produce a negative pressure equal to the maximum fluid column height in the drainage tube. This may be half the length of the drainage tube. For a urinary drainage tube with a maximum length of 60 inches, the maximum negative pressure required would be approximately 30 inches of H2O, or 56 mmHg.

[0107] Other techniques can be used to induce urination through tubes and / or systems involving pulsating mechanical, vibroacoustic, thermal, vibration, pinching, rolling, or electromagnetic stimulation, thereby causing movement of at least one of the drainage line and the fluid within it. In some embodiments, rolling stimulation involves the successive compression of multiple lumens, so that not all lumens are compressed simultaneously.

[0108] In another embodiment, the airlock is removed by a collapsible drainage tube located within a more rigid torsion-resistant tube. Figure 14A shows such an embodiment in an unfolded form. The inner collapsible drainage tube 1402 is located inside the outer torsion-resistant tube 1404. Figure 14B shows an embodiment in which the inner collapsible tube is folded. The drainage tube is periodically folded, for example, by applying positive pressure to the space between the collapsible tube and the torsion-resistant tube, or by applying negative pressure inside the collapsible tube. As the drainage tube collapses, urine is then pushed out from the patient towards the collection container.

[0109] In another embodiment, the drainage lumen cleaning mechanism comprises a tube with an inner diameter of less than approximately 0.25 inches, so that air pockets cannot move beyond the length of the tube. This is made possible by surface tension within the small tube, preventing fluid movement when one end of the tube is closed to the atmosphere (as in the case of the bladder). Thus, the drainage tube remains constantly filled with urine, and since urine is incompressible, the same amount of urine must be drained from the drainage tube for each volume of urine produced. In another embodiment, the inner diameter is less than 0.125 inches. In another aspect, the drainage tube acts as a siphon, providing a small, safe amount of vacuum to the bladder. Alternatively, using a small lumen drainage tube, air can be periodically introduced into the lumen through a vent / valve. Negative pressure caused by a pump may facilitate this. Due to the negative pressure caused by the pump, urine continues to flow into the collection reservoir, preventing airlock.

[0110] Furthermore, using smaller diameter tubing results in a smaller amount of residual urine in the drainage tube compared to conventional techniques. A smaller residual volume is preferable because urine can move more quickly from the patient's bladder to the collection container. This speed of transport is important for measuring more recently produced urine. This is especially important for patients with low urine production rates, as it takes more time for urine to be transported from the bladder to the collection container. For example, in a patient producing only 10 mL / hr of urine using a standard drainage tube (residual volume of approximately 40 mL), measuring urine in the collection container will delay true urine production by 4 hours. In contrast, with smaller tubing (such as tubing with a residual volume of approximately 5 mL), the measurement will only delay true production by 30 minutes. In some embodiments utilizing small diameter tubing, with or without vents / valves, a pump to supply negative pressure to the drainage line is not required.

[0111] Figure 15 shows an embodiment of a device well suited for draining a chest tube or other drainage tube that applies a constant negative pressure to a patient. These embodiments may also be suitable for draining urine from the bladder or fluid from other cavities. Any of the features disclosed in connection with chest tube drainage may be applied to bladder drainage or other body cavity drainage. Fluid is drained from the patient through a drainage lumen 1585 connected to a collection tube 1582. Drainage is assisted by applying negative pressure to the collection container 1582, for example by attaching a suction tube 1583 to a suction in the hospital wall. Suction may also be applied by other means, such as a pump disclosed elsewhere in this specification. Air enters the drainage lumen 1585 through a valve 1584 having a cracking pressure equal to the desired negative pressure. Selecting the correct cracking pressure (e.g., -15 to 0 mmHg, or 10 mmHg) ensures that the pressure on the patient remains at this level, as long as the hospital wall suction / pump can produce sufficient suction in the collection container 1582. Preferably, the drainage lumen used for draining the chest tube is as large as possible while maintaining the siphon. Appropriate inner diameters include, but are not limited to, approximately 1 / 4 inch, 5 / 16 inch, or 3 / 8 inch.

[0112] Figure 16 shows another embodiment of a device well suited for draining a chest tube or other drainage tube that applies constant negative pressure to a patient. The fluid is drained from the patient through a drainage lumen 1688, and negative pressure is applied using a pump mechanism 1686. A pressure sensor 1687 is located inside the drainage tube on the patient side and thereby measures the pressure applied to the patient. The measurement obtained by the sensor 1687 is sent back to a controller that controls the pump mechanism 1686, and the pressure produced by the pump mechanism 1686 is adjusted to maintain the pressure on the sensor 1687 (and the patient) at a desired level. The pressure sensor 1687 may also be located elsewhere in the system. The sensor can also be used to passively monitor the pressure on the patient side of the tube, providing the clinician with information about the suction level being applied. Figure 16 shows the pump on the patient side of the drainage reservoir, but alternatively, the pump may be on the opposite side of the drainage reservoir, with the reservoir between the patient and the pump.

[0113] In another embodiment of the present invention used for draining a chest tube, the volume of fluid being drained is measured to provide a clinician with information regarding the drainage status of the chest tube. This measurement can be achieved by any suitable means, in particular the means described for measuring urine volume.

[0114] In addition to eliminating airlocks, some of the airlock clearance designs detailed above have been shown to effectively remove deposits and thrombi from urinary drainage lines. These issues plague current urinary drainage tubes, particularly those with monitoring techniques in smaller lumen drainage tubes and drainage bags, and the present invention offers a modern technological advancement by automating the removal of these drainage block fragments and blood clots. This feature is particularly useful when used with a balloon at the tip of a Foley or in combination with pressure sensing in fluid communication with the bladder. This allows for monitoring of pressure and vacuum within the bladder, enabling more aggressive pumping based on the actual bladder pressure until the blood clot / obstruction is cleared. Without this pressure / vacuum sensing, the bladder mucosa is exposed to excessive vacuum, and pumping of fluid within the drainage tube can lead to clinical complications in the bladder, such as aspiration trauma.

[0115] In another embodiment shown in Figure 17, the gas sampling lumen 1790 extends along the length of the drainage tube and ends with a gas-permeable, liquid-impermeable filter 1791 that remains in contact with the urine, with its meniscus 1792 further away from the patient than the filter. If measurement of oxygen, carbon dioxide, or other gases is required, the air in the gas sampling lumen 1790 is drawn into the base 1789 of the drainage device for analysis. This configuration allows for accurate gas analysis even in embodiments of the device that allow air to flow into the drainage line, as shown in Figures 10 to 16.

[0116] As shown in Figure 18, the active ventilation system includes a vent 1802, a drainage line 1804, a 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 a connection to a urinary catheter is made. The fluid flows from the patient through the drainage line and is collected in the collection container. The pump in this embodiment does not act directly on the drainage line but rather creates a vacuum in the collection container. The pump facilitates drainage by applying negative pressure to the collection container, forcing the liquid into the drainage line. Preferably, the collection container is 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 permeation of gas (preferably air) but prevents the permeation of liquid. This prevents substantial negative pressure from being applied to the patient by allowing air to enter the system. Such a mechanism prevents, for example, aspiration trauma to the bladder wall.

[0117] The pump in this system may include, but is not limited to, a peristaltic pump, a diaphragm pump, or a centrifugal pump; it can be any suitable pump for pumping gas. For proper functioning, it is desirable that the pump be able to produce a negative pressure equal to the maximum liquid column height in the drainage tube. This may be half the length of the drainage tube. For a urinary drainage tube with a maximum length of 60 inches, the maximum required negative pressure would be approximately 30 inches of H2O, or 56 mmHg.

[0118] As shown in Figure 19, the active vent system for draining bodily fluids has additional vents. One such vent, vent 1962, may be located above the collection container and allow air to escape from the collection container. This prevents pressure buildup as new fluid enters the container, as each volume of fluid entering the system can be offset by the same volume of air leaving the system. Another such vent, vent 1964, may be located between the collection container and the pump. This vent allows the permeation of gas (preferably air) but prevents the permeation of fluid to prevent bacteria and viruses from entering and exiting the collection container and drainage tube. Preferably, this vent is sterile grade, meaning that the air passing through it is considered sterile. The vent (not shown here) may or may not be on the patient side of the drainage line.

[0119] As shown in Figure 20, pressure offset can be achieved with a single vent in the collection container. In this case, the vent, vent 2072, is located between the collection container and the pump as previously described, but an additional valve 2074 allows air to escape from the collection container in the presence of positive pressure. This valve can expel air from the system but cannot enter it. When the pump is activated, the one-way valve must close, drawing air out of the collection container, which creates negative pressure in the collection and facilitates the flow of fluid through the drainage line. The vent may or may not be present on the patient side of the drainage line (not shown here).

[0120] Infection detection

[0121] Figure 21 shows an embodiment of a collection container, chamber, or cassette that may be included in a sensing Foley catheter system for detecting bacteria, blood, and / or other substances in urine using UV / optical / Raman spectroscopy. The cassette 2100 includes a container wall 2102, which is preferably rigid. Urine 2106 is collected in the cassette. If urine collection is too fast, or if there is any obstacle to emptying the cassette, an overflow area 2104 allows excess urine to be discharged from the cassette. The cassette 2100 may include an optically transparent compartment 2110, which is preferably incorporated into the outer wall of the cassette, and a reflector compartment 2112, which is preferably in or incorporated into the inner wall of the cassette. Here, “optically transparent” means that light of the required analytical wavelength can be transmitted through the optically transparent portion. The optically transparent portion is preferably made of an ultraviolet-transmitting material such as polymethyl methacrylate, polystyrene, acrylic, or quartz. The wall thickness must be sufficiently thin so that the appropriate UV wavelength can be transmitted through the optically transparent portion. For example, the thickness of the optically transparent section may be approximately 0.5 mm to approximately 0.7 mm. Alternatively, the thickness of the optically transparent section may be approximately 0.5 mm to approximately 0.6 mm. Alternatively, the thickness of the optically transparent section may be approximately 0.6 mm to approximately 0.7 mm. Alternatively, the thickness of the optically transparent section may be less than approximately 0.7 mm.

[0122] The UV / light transmitter / receiver 2108 transmits UV or other wavelengths of light of the appropriate wavelength to a reflector 2112 in the cassette through an optically transparent compartment 2110, the urine in the cassette. The UV / light transmitter / receiver may be integrated into or connected to the controller component of the sensing Foley catheter system. The light is reflected back to the UV / light receiver and transmits the collected data to the controller for signal analysis. Multiple UV / light wavelengths can be analyzed simultaneously or sequentially. In addition to light within the UV range, light outside the UV range can be used. The physical volume of urine between light transmission and reception is preferably maximized for a stronger signal that reflects the concentration of one or more substances in the urine. The transmitter / receiver can be located as shown in Figure 21 or in other areas of the cassette. The receiver may be in a different location from the transmitter, and the reflector may not be necessary or present. Because the urine in the cassette is frequently emptied, UV / 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 essentially or near real time. This is particularly important for the rapid identification of infections, such as urinary tract infections and catheter-associated urinary tract infections (CAUTIs). UV / light detection can also be performed at other locations in the Foley catheter system sensing, including drainage tubes and other sampling areas.

[0123] Infection can be identified by analyzing urine for bacteria, red blood cells, plasma, and / or white blood cells using UV / optical spectroscopy. Figure 22 shows the various absorption wavelengths of E. coli, red blood cells, and plasma in urine. The presence of plasma / white blood cells and / or bacteria in urine is both an indicator of infection. The presence of red blood cells may not be an indicator of infection. Therefore, it is desirable to distinguish between red blood cells and bacteria / plasma / white blood cells in urine. The spectroscopic characteristics of red blood cells are significantly different from those of either bacteria or plasma / white blood cells at a wavelength of approximately 414 nm, so the signal of red blood cells can be separated from the signals of bacteria and / or plasma / white blood cells, and infection can be identified by analyzing the absorption of light at this wavelength. The characteristics of plasma and bacteria are different from each other at wavelengths of 260 nm and 280 nm, so these wavelengths can be used to distinguish between plasma and bacteria. However, both plasma and bacteria may be present during infection.

[0124] Other wavelengths and techniques can also be used to detect various substances in urine or collected / excreted bodily fluids. UV / light absorption can also be used to detect turbidity. Dyes, drugs, or reactive substances can be introduced into the system or coated inside the system, on the cassette, etc., to react with substances in the urine and assist in the analysis. Any type of sensor can be used to detect the substance or quality of collected urine intermittently or continuously in real time. For example, a sensor that detects magnesium in urine can be used to diagnose pre-eclampsia or eclampsia. Lactate sensors can be used to test for lactate (or lactate dehydrogenase) in urine. Identifying lactate in urine may be an early indicator of sepsis. Lactate sensors may include enzyme lactate sensors. For example, 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 in their entirety by reference and are available for use herein.

[0125] Using appropriate sensors, drugs or drug residues can be detected in collected urine. Other substances or characteristics of collected urine that may be detected include color, clarity, odor, specific gravity, osmotic pressure, pH, proteins, glucose, creatinine, nitrites, leukocyte esterases (WBC esterases), ketones, red or white blood cells, plaque, crystals, bacteria, yeast cells, parasites, squamous epithelial cells, and others.

[0126] CAUTI or infection can be identified and / or reduced by several methods, including analyzing urine using spectroscopy, light wavelengths, etc., to detect contaminants early; reducing bladder trauma caused by aspiration; reducing bladder urinary retention; reducing the presence of bacteria or microorganisms by using antimicrobial coatings or implant materials such as silver or other materials; improving the accuracy of bladder pressure measurement by reducing bladder aspiration; and improving the accuracy of urine output measurement by reducing airlocks in the system and bladder aspiration. A pressure spike caused by bladder aspiration can be defined as a pressure measurement of less than approximately -20 mmHg. Alternatively, a pressure spike caused by bladder aspiration may be defined as a pressure measurement of between approximately -10 mmHg and less than approximately -20 mmHg. Alternatively, a pressure spike caused by bladder aspiration can be defined as a pressure measurement of less than approximately -10 mmHg.

[0127] CAUTI can also be reduced by using UV light, or any effective wavelength of light or radiation, to reduce bacteria in the urine and / or within the system. Urine can be treated using ultraviolet light to sterilize the urine within the cassette or elsewhere in the system. For example, UV light may sterilize the urine as it enters the cassette, for example, at the inlet valve 10104 as shown in Figure 101A, or within the cassette, or above the cassette, for example, in the drainage tube above the cassette.

[0128] Figure 23 shows an embodiment of the cassette including a baffle or flap 2302. This baffle / flap prevents urine from being drawn up along the inner wall of the cassette, as indicated by the dotted arrow. The baffle prevents urine from being drawn up beyond the point of the baffle, allowing the urine to return to the measuring reservoir below.

[0129] Priming

[0130] Aspects of disclosed techniques that are particularly advantageous for achieving high-resolution signals from pressure profiles from specific physiological sources (such as peritoneal pressure, respiratory rate, heart rate, relative tidal volume, cardiac output, relative cardiac output, and absolute cardiac volume) may be monitored in relation to adjusting and maintaining the pressure balance on both sides of a pressure interface represented by the membrane of a pressure-sensing balloon. This pressure balance may be referred to as the pressure difference. In some embodiments, the preferred pressure difference is zero or near zero. In some embodiments, the preferred pressure difference may be a different value. The pressure acting on the outer surface of the balloon (facing the inner surface of the bladder) varies depending on the patient's physiological function. The pressure on the inner surface of the balloon (fluid-communicating with the fluid column) is prone to degradation due to fluid leakage and incomplete sealing.

[0131] When a sensing Foley catheter is first inserted, an external pressure is generally applied to the fluid column against the pressure interface until it reaches a first approximation of the pressure applied from within the bladder to the pressure interface. The pressure signal measured at the pressure interface has the greatest amplitude when the pressure difference is nearly zero. Therefore, the amplitude of the pressure signal can be used to adjust the pressure applied from the fluid interface to the pressure interface. This process of applying an appropriate amount of pressure to the interface is sometimes called priming the fluid column or balloon. As mentioned above, the fluid column needs to be primed or readjusted from time to time because the pressure on both sides of the pressure interface can change. The need for repriming can be monitored by testing small changes in pressure to achieve the maximum amplitude of the pressure signal profile. Alternatively, priming can be performed automatically from time to time via a controller.

[0132] Embodiments of the disclosed systems and methods include automatic pressure regulation by a controller. Thus, the regulation system can detect the 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, a pressure regulation circuit that adjusts the volume and pressure of the balloon may inflate the balloon until physiological pressure is detected. Upon sensing this rate, the pressure regulation controller adds or removes small amounts of air in a routine or programmed sequence until the amplitude of the sensed wave is maximized. A control feedback loop between the optimally regulated pressure (which manifests as balloon pressure and volume) and the sensed physiological pressure profile is continuously repeated as needed to ensure high-fidelity measurement of physiological data. In some embodiments, automatic pressure regulation may be performed in the apparent background while physiological data is being transmitted and displayed; in other embodiments, the system may pause the transmission of physiological data during the pressure regulation sequence.

[0133] Embodiments of the disclosed technology include a gas delivery system capable of delivering gas in a priming operation, thereby allowing pressure to be applied to a proximal fluid column on a side facing the proximal side of a pressure interface. The gas source, such as compressed air or liquid, is held in a storage tank. Taking CO2 as an example, the CO2 is controlledly released from the storage tank via a pressure regulator capable of reducing 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 to about 2.5 psi. A pressure safety valve is a safety feature that prevents gas flow at levels exceeding 2.5 psi in the event of a failure of the upstream regulator. The CO2 then exits the pressure safety valve and enters the catheter line through a first solenoid-controlled filling valve, eventually filling a balloon containing a pressure sensing interface. When the pressure in the balloon rises to a level of 30 mmHg, the first solenoid-controlled valve closes. A second solenoid-controlled valve distal to the first valve acts as a drain valve, allowing pressure from the catheter to be released to a target pressure. Alternatively, the drain valve is activated until a respiratory waveform is detected, after which the balloon is optimally primed and the valve is closed. The drain valve may be subject to proportional control based on voltage or pulse width modulation (PWM), which allows the drainage rate to be sufficiently slow to reach the target pressure and close the valve before overshoot. Alternatively, the balloon may be filled with room air using a peristaltic pump or other air pump.

[0134] Figure 24 shows a graph illustrating a pressure balloon priming method in several embodiments. Here, a small fluid burst (approximately 0.3 cc) is added to a pressure-sensing balloon, and the pressure inside the balloon is measured. Small fluid bursts are introduced until the measured pressure inside the balloon settles to a stable pressure 2401. This transition is indicated by an inflection point 2402. Volume bursts are introduced past this point until the measured pressure begins to increase rapidly (e.g., when the slope of the curve 2404 is greater than approximately 2 mmHg / 10 ms). This inflection point is indicated by 2406. At this point, the pressure inside the balloon drops to around or slightly above the stable pressure 2401. In some embodiments, this pressure represents the priming pressure to be measured. This process is also shown in the flowchart in Figure 27.

[0135] Alternatively, priming a pressure balloon involves pressurizing the balloon well above 0 mmHg, then removing a small amount of air / gas / fluid, and monitoring the pressure of the pressure balloon. The pressure of the pressure balloon stabilizes as it approaches the optimal priming pressure. To determine this optimal pressure, pressure measurements are taken as a small amount of air is removed from the pressure balloon, and if the subsequent pressure measurements are essentially the same (within approximately 2 mmHg of each other), the balloon is at the optimal priming pressure. If the two subsequent measurements are not essentially equal, the pressure balloon is repressurized well above 0 mmHg, and the process is repeated. Pressure measurements taken as a small amount of air is removed from the pressure balloon are taken over a period of approximately 5 to 15 seconds to compensate for the effect of breathing on the pressure measurements. In some embodiments, the pressure signal may require a short stabilization period after a small amount of air / gas / fluid has been removed from the pressure balloon before the pressure measurements are taken.

[0136] A small amount of liquid ejected is approximately 0.2cc to 0.4cc. A small amount of liquid ejected may be approximately 0.1cc to 0.5cc. A small amount of liquid ejected can be up to approximately 0.5cc. A small amount of liquid ejected can be up to approximately 1.0cc.

[0137] Figure 25 shows a graph illustrating a pressure balloon priming method in several embodiments. This method is similar to the method shown in Figure 24, except that there is no rupture and the pressure inside the pressure-sensing balloon increases more smoothly. A liquid volume is added to the pressure-sensing balloon and the pressure inside the balloon is measured. The balloon pressure is increased until the measured pressure inside the balloon settles at a stable pressure 2505. This transition is shown at the inflection point 2506. The balloon pressure increases beyond this point until the measured pressure begins to increase rapidly (e.g., when the slope of the curve 2510 is greater than approximately 2 mmHg / 10 ms). This inflection point is shown at 2508. At this point, the pressure inside the balloon decreases to a pressure around or slightly above the stable pressure 2505. This pressure represents the optimal or priming pressure in some embodiments. This process is also shown in the flowchart of Figure 28.

[0138] Figure 26 shows a flowchart of the balloon priming process in a particular embodiment of the present invention. Embodiments of the disclosed system and method include automatic pressure regulation by a controller. Thus, the regulation system can detect the optimal target pressure and volume and inflate the balloon by monitoring the sensed pressure signal and adding or removing air as needed. For example, upon catheter insertion, a pressure regulation circuit adjusts the balloon's volume and pressure, inflating the balloon until it detects physiological pressure. Once this rate is sensed, the pressure regulation controller adds or removes small amounts of air or fluid (about 0.3 cc) in a periodic sequence until the amplitude of the sensed wave is maximized. A control feedback loop between the optimally regulated pressure (which manifests as the balloon's pressure and volume) and the detected physiological pressure profile is continuously repeated as needed to ensure high-fidelity measurement of physiological data. In some embodiments, automatic pressure regulation may be performed in the apparent background while physiological data is being transmitted and displayed, and in other embodiments, the system may pause the transmission of physiological data during the pressure regulation sequence.

[0139] The trace amount of air or liquid may be approximately 0.2cc to 0.4cc. The trace amount of air or liquid may be approximately 0.1cc to 0.5cc. The maximum amount of air or liquid is approximately 0.5cc. The maximum amount of air or liquid may be approximately 1.0cc.

[0140] In some embodiments, balloon priming may be based on the characteristics of the system. The pressure balloon may be inflated one or more times to characterize the system, which includes an ultrasonic transducer, a pressure pump, system resistance, and the pressure balloon itself. The pressure balloon may be pressurized beyond a certain pressure range to determine the characteristics of the particular system at that point. This information is used to optimize the inflation pressure of the pressure balloon.

[0141] Loop controller

[0142] Certain patient parameters measured by sensing Foley catheter systems or other means are affected by the treatment of the patient by medical devices.

[0143] The loop controller can be integrated with the controller of a sensing Foley catheter system (either on the same device or a different device) to interpret patient parameters and control patient treatment.

[0144] For example, IAP can be used to control the IV infusion rate. If the IAP becomes too high, the infusion rate may be reduced or stopped until the IAP returns to an acceptable range. IAP, combined with relative stroke volume and / or stroke volume variability (variations in the size of cardiac pulses seen in the bladder, etc., during the respiratory cycle), allows for better control of IV fluid or blood product infusion using IAP as an indicator of excess fluid and increased relative stroke volume, and reduces stroke volume variability as an indicator of the need for additional fluid. Urine output may be further added to the control loop to provide an indicator that the fluid state has recovered when urine output returns. Heart rate and respiratory rate can be combined to control drug infusion (type of drug, infusion rate, frequency, dosage, etc.). In this way, drugs can be used to keep the patient more stable, which is determined by the heart and respiratory rate. IAP and respiratory rate can also be used to control the ventilator or ventilator. If the IAP rises, the positive end-respiratory pressure (PEEP) supplied by the ventilator also rises to overcome this pressure. Indicators of insufficient ventilation can be seen in tissue oxygenation and / or spontaneous respiratory rate, which can be viewed as an underlying signal for mechanical ventilation. This signal can be extracted during mechanical ventilation, or the loop controller can pause the mechanical ventilator to allow for more precise and accurate detection of the underlying respiratory rate / respiratory drive. This IAP, tissue oxygenation and / or respiratory rate, is used to alert healthcare providers of a deterioration in the patient's condition and / or to provide automatic adjustment of ventilator settings, including respiratory rate, PEEP, %O2 inhalation, and other settings. In an ideal scenario, these parameters can be used in the loop controller to monitor and control treatment in a way that is notified by machine learning and algorithmic adjustments. These are just a few examples, and many combinations exist. One or more parameters can be used to control one or more treatment devices.

[0145] Figure 29 shows an embodiment of a loop controller in a patient environment. In this example, the loop controller receives patient parameter input from a sensing Foley catheter 2902. The sensing Foley catheter is located in the patient's bladder 2904 and includes a retaining balloon 2908 and a pressure sensing balloon 2910. The sensing Foley catheter may include other sensors disclosed herein.

[0146] The sensing Foley catheter 2902 includes a retaining balloon inflation lumen, a pressure balloon sensing lumen, and a ureteral 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 controller 2928. The ureteral lumen is connected to a urinary drainage tube 2912. The urinary drainage tube enters a urinary reservoir 2914, which may be connected to a urine volume measuring device 2916 or incorporated into a controller as disclosed herein. Furthermore, urine drainage can be controlled by a urinary pump 2918, which may be located in the urinary drainage tube, incorporated into a controller, or located on the non-patient side of the controller as disclosed elsewhere herein.

[0147] This patient is shown with a ventilator mask 2922, supplied with respiratory gas through a ventilator tube 2924. The flow and supply of respiratory gases are controlled by the ventilator 2926.

[0148] The loop controller 2928 is connected to the urine volume measuring device 2916, the urine pump 2918, the pressure transducer 2920, and the ventilator 2926 via connectors 2930, 2932, 2934, and 2936, respectively. The connectors may be wired or wireless. Alternatively, in this embodiment and other embodiments, some or all of the urine volume measuring device 2916, the urine pump 2918, and / or the pressure transducer 2920 may be incorporated into the controller 2928.

[0149] In this example, the loop controller 2928 receives patient parameter inputs from the urine volume measuring device 2916 and the pressure transducer 2920, and can use the information provided by these parameters to control the urine pump 2918 and the ventilator 2926. 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 sample, urine output, and other parameters, including those disclosed herein.

[0150] For example, if the loop controller receives parameter information indicating that the patient's IAP is elevated, the loop controller can control the perfusion rate, pressure, or other parameters of the ventilator. 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 elevation of IAP and abnormal tissue oxygenation parameters, the loop controller may control the output and urine output rate of the ventilator 2926 by controlling the urine pump 2918.

[0151] The loop controller continues to monitor patient parameters and adjusts the therapeutic medical device accordingly. Once the patient parameters normalize, the control of the therapeutic medical device is adjusted accordingly so that the feedback loop controlled by the loop controller becomes a closed loop. The loop can also be manually adjusted as needed, in which case the loop can be an open loop or a semi-closed loop.

[0152] Figure 30 shows another example of a loop controller in a patient environment. In this example, there is a venous (IV) line 3002 in a blood vessel in the patient's arm. An IV fluid bag 3004 is raised to allow IV fluid to drip and / or flow into the patient through the IV line 3002. A valve 3006 controls the flow rate of IV fluid to the patient by allowing the fluid to flow freely, restricting the flow, or stopping the flow. Here, the valve 3006 is controlled by a loop controller 2928 via a connection 3008. The IV fluid bag 3004 may contain hydrating fluid and / or drugs. One or more IV bags may be involved, and one or more valves may control the IV bags. The loop controller can control the flow rate and contents of IV fluid to the patient based on patient parameters received by the loop controller.

[0153] Figure 31 shows another example of a loop controller in a patient environment. In this example, the patient has a drainage line 3102 inserted into the abdomen. Fluid from the abdomen may flow from the patient to a receptacle 3104. The fluid flow may be controlled by a pump 3106 controlled by a loop controller 2928 via a connection 3108. The loop controller can control the fluid flow from the patient to the container 3104 via the pump 3106 based on the patient parameters it receives. For example, if the IAP is abnormally high, the loop controller can increase or start the rate of fluid removal from the patient by controlling the pump 3106.

[0154] Figure 32 shows another example of a loop controller in a patient environment. In this example, there is a venous (IV) line 3202 in a blood vessel in the patient's arm. A drug infusion device 3204 controls the flow rate of drug to the patient via the IV line 3202. Multiple drug infusion devices may be used, where the drug infusion device 3204 is controlled by a loop controller 2928 via connection 3206. The drug infusion device 3204 may contain any suitable fluid and / or drug. The loop controller may control the flow and content of drug to the patient based on patient parameters received by the loop controller.

[0155] These examples illustrate some of the medical devices that can be controlled with a loop controller, but any medical device can be used.

[0156] Figure 33 is a detailed diagram of the loop controller. The loop controller 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 and urine volume, pressure profiles from the bladder, and sensor information from the Foley catheter or other device. Further analysis of the pressure profile information from the bladder can determine IAP, respiratory rate, heart rate, stroke volume, sepsis index, AKI index, and other patient parameters. This analysis may be performed on the loop controller 2928 or on a separate controller connected to the loop controller by either a wired or wireless connection. The connection may be made via the Internet, intranet, WAN, LAN, or other network, or locally via Bluetooth®, Wi-Fi, etc.

[0157] A loop controller receives one or more inputs, analyzes the data, and determines whether it is necessary to change the control of the treatment device. It can control one or more medical devices to bring the patient's parameters within a target range. Once the patient's target range is achieved, the loop controller returns the controlled medical devices to their standard state. The standard state varies for each medical device and may vary from patient to patient. Similarly, the target range for patient parameters varies from patient to patient and depending on the patient's condition. For example, the target range for respiratory rate may differ depending on whether the patient is sedated or not.

[0158] Embodiments of this technology can also automatically adjust intravenous fluid or drug infusion rates based on feedback from cardiac output or sensed respiratory rate. In one such embodiment, the patient-controlled analgesic pump can be stopped if the respiratory rate becomes too low. In this group, respiratory depression can be fatal, and this protective measure prevents overdose. The automated feedback system may also be advantageous in high-volume resuscitation procedures, in which case the infusion rate can be adjusted based on intra-abdominal pressure, alerting to prevent abdominal compartment syndrome and slowing the infusion rate as intra-abdominal pressure increases. Yet another automated feedback function may provide direct feedback to the ventilator system to provide optimal ventilation gas pressure. In settings with increasing abdominal pressure, typical ventilator settings may not provide the patient with adequate breathing. Automatic adjustment of ventilator settings based on intra-abdominal pressure feedback from this embodiment may advantageously provide optimal patient ventilation. Embodiments of this technology may also be applied as modifications in the application or understanding of other diagnostic measurements. For example, when intra-abdominal pressure increases, central venous pressure may be dramatically distorted. By providing direct access to these data through a central venous pressure reporting system, automated correction and accurate reporting of these critical physiological parameters become possible. Embodiments of this technology may also be used in various other ways to automate treatments, including the infusion of fluids that may further contain activators such as vasopressors or diuretics, in response to increases or decreases in cardiac output or other parameters.

[0159] Other inputs and outputs to the loop controller include nutrition delivered via a feeding tube or vein, wound drainage, fecal output, sweat output, and exhaled vapor output.

[0160] In addition to directly controlling the treatment device, the loop controller 2928 may sound alarms, including audible alarms, email alarms, text alarms, and pager alarms. The loop controller 2928 may provide outputs to other systems for system integration, such as outputting information to electronic health records, other data archiving systems, or other systems. The loop controller 2928 may also receive inputs from various EHRs, EMRs, or other systems.

[0161] Medical treatment may be administered to the patient as a result of data collected and / or analyzed by a sensing Foley catheter system. This treatment may be a drug therapy automatically administered via a loop controller, or it may be a traditional drug therapy administered manually, i.e., orally, by injection, etc.

[0162] Further medical diagnoses can be performed based on the detection results from the Foley catheter system.

[0163] specific gravity

[0164] Urine specific gravity can be measured using pressure and ultrasound measurements with a sensing Foley catheter. Figure 34 shows a plot illustrating how volumetric ultrasound and pressure measurements diverge along with liquid density. The liquid being measured is synthetic urine concentrate with a specific gravity of approximately 1.100.

[0165] For a liquid with a specific gravity of 1.000, two measurement methods can be calibrated and yield the same volume measurement. However, as density increases, they begin to diverge. Since V=A*h and P=ρ*g*h, or V=A*ρ*g / P, as pressure increases density, the volume measurement increases. In the case of ultrasound, since V=A*h, v=h*2 / t, and v=(E / ρ)^(1 / 2), V=A*(E / ρ)^(1 / 2)*t / 2. V: Volume A: Cross-sectional area h: liquid height P: pressure ρ: liquid density g: gravity v: velocity of sound t: The time it takes for sound to reflect E: Bulk modulus of a liquid

[0166] Simply put, as the density of a liquid increases, the pressure also increases, causing significant distortion in the measurement. Simultaneously, sound travels faster, causing less distortion in ultrasonic measurements. By measuring how much they diverge, the density of the liquid can be determined. This assumes that the temperature is constant, but temperature can be monitored and corrected for temperature variations. Volume measurement using ultrasound and pressure, as well as temperature measurement, can be performed using a sensing Foley catheter. In this way, a sensing Foley catheter combined with a controller can measure the specific gravity of urine.

[0167] Reduction of condensation

[0168] Balloon catheters, especially those designed to remain inside a human or animal's body for a relatively long period, may leak over time. For example, a balloon inflated with air or another gas may leak air over time. Or, a balloon filled with liquid may leak liquid over time. The reverse is also true. A balloon filled with gas or air present in a liquid such as urine or blood may leak liquid over time. This is especially true if the balloon is inflated at a relatively low pressure.

[0169] Sensing Foley catheters are an example of a balloon designed to inflate for a relatively long time at a relatively low pressure. In this example, where the balloon is designed to measure pressure, the balloon can be inflated at a relatively low pressure, and as a result, can be manufactured from a relatively soft and thin material. Due to the low inflation pressure and the soft balloon material, liquid may leak into the balloon over time. Liquid inside the pressure-measuring balloon can negatively affect highly sensitive pressure measurements, especially if the liquid moves into the catheter lumen where the pressure measurement is being taken.

[0170] One embodiment to solve this problem involves placing a very small-pore filter or hydrophobic filter between the pressure-measuring balloon and the pressure-measuring lumen of the catheter. This allows the balloon to be inflated and continuously primed to maintain pressure, and also allows pressure measurement through the catheter lumen. Air or gas can pass through the filter, but fluids cannot.

[0171] Another embodiment involves making a balloon from a low-permeability material.

[0172] Another embodiment involves reinjecting the gas inside the balloon by alternately applying vacuum and pressure to the balloon through one or more lumens.

[0173] Another embodiment involves circulating gas within a balloon by having multiple lumens access the balloon. One lumen can be used to introduce gas into the balloon, and another lumen can be used to draw gas out of the balloon.

[0174] Another embodiment involves using a desiccant within the balloon, the balloon lumen, the gas supply to the balloon, or any combination thereof.

[0175] Figure 35 shows the distal end of a Foley balloon catheter that may benefit from reduced clotting. In this example, the balloon catheter is designed to be placed in a patient's bladder to help drain urine from the bladder. The catheter includes a retaining balloon 3506 that secures the catheter within the bladder. The catheter shaft 3502 contains the lumen of the catheter. An opening 3504 allows urine from the bladder to be drained through the catheter and exit through the proximal end of the catheter (not shown). An opening 3508 is for inflating and deflating the retaining balloon. A pressure-sensing balloon 3510 inflates and deflates through an opening 3512. The pressure-sensing balloon 3510 transmits a pressure signal from within the bladder through the pressure lumen in the catheter shaft to a pressure transducer near the proximal end of the catheter.

[0176] Under certain circumstances, fluid may leak into the pressure balloon 3510 over time. Furthermore, the fluid moves from within the pressure balloon 3510 through the opening 3512 to the catheter shaft 3502. Fluid in the pressure lumen can adversely affect pressure measurements from the pressure balloon. Consequently, it is desirable to prevent fluid from moving from within the pressure balloon through the opening 3512, or, if possible, reduce the amount of fluid entering the pressure balloon.

[0177] Figure 36 shows an embodiment of a filter inside a balloon. The filter 3602 is located between the inside of the balloon 3510 and the pressure lumen inside the catheter opening 3512. The filter 3602 is preferably made of a material that allows gas to pass through but not fluid. For example, the filter can be made from a hydrophobic membrane such as Versapor, PTFE, or ePTFE. The filter may also be made of a polymer such as nylon or other suitable material. The pore size may be about 3 microns, or about 5 microns, or in the range of about 0.2 microns to about 5 microns, or in the range of about 5 microns to about 10 microns. The thickness of the filter is in the range of about 6 mils to about 12 mils. Alternatively, the thickness of the filter may be in the range of about 1 mil to about 6 mils. The pore size is related to the sensitivity of the balloon. For example, a filter with a 5-micron pore size may be suitable for a balloon inflated to about 5 mmHg to about 20 mmHg and can detect pressure differences up to a resolution range of 0.01 mmHg. If the pressure measured by the pressure balloon is not sensitive enough, a filter with smaller pores can be used. If the pressure measured through the pressure balloon needs to be more sensitive, a filter with larger pores can be used.

[0178] Figure 36 shows a filter in the form of a tube that surrounds the catheter shaft at the opening 3512 and completely covers the opening. The filter may be bonded to the catheter shaft at its ends using a suitable adhesive or other means such as heat shrinkage. The seal between the filter and the catheter is ideally gas impermeable so that gas entering and leaving the balloon 3510 through the opening 3512 must pass through the filter 3602.

[0179] Figure 37 shows another embodiment of the invention, which includes a smaller catheter shaft with the filter mounted inside the balloon. The catheter shaft 3704 inside the balloon has a smaller diameter than the catheter shaft 3706 that is not below the balloon. This prevents the added bulk of the filter 3702 from increasing the diameter of the deflated balloon.

[0180] Figure 38 shows an embodiment of Figure 37 in which the balloon has deflated, and it can be seen that the reduction in the diameter of the catheter shaft below the balloon region prevents significant inflation of the balloon catheter.

[0181] Figure 39 shows another embodiment of the filter below the balloon. In this embodiment, the filter 3902 is a flat or curved filter piece that is bonded to the catheter shaft via adhesive or other suitable means, rather than wrapping around the entire catheter shaft. The adhesive preferably completely seals the filter around its edges without interfering with the balloon inflation / deflation / pressure measuring opening 3512.

[0182] Figure 40 shows another embodiment of filter 4002, which has a shorter filter length.

[0183] Figure 41 shows another embodiment of a balloon catheter with a filter. In this embodiment, the balloon catheter has two lumens that are in fluid communication with the balloon. Filter 4102 covers opening 4104, while opening 4106 is not covered. In this embodiment, openings 4104 and 4106 may each access separate lumens of the catheter, or the same lumen. In embodiments where they access separate lumens, balloon inflation, deflation, and pressure measurement may be performed through either lumen. For example, pressure measurement may be performed through the lumen that is in fluid communication with opening 4106 until the accumulation of fluid in the lumen adversely affects the pressure measurement. At this point, the pressure transducer may be switched to the lumen that is in fluid communication with opening 4104, and pressure measurement may be performed through the fluid-free lumen.

[0184] Alternatively, pressure measurement may be performed through a lumen that is in fluid communication with the opening 4106 until the accumulation of liquid in the lumen adversely affects the pressure measurement. At this point, gas can be introduced into the lumen that is in fluid communication with the opening 4106 to remove fluid from the lumen. At the same time, gas can be drawn from the balloon through the lumen that is in communication with the opening 4104. In this way, liquid can be removed from the lumen that is in communication with the opening 4106, and pressure measurement can be resumed through that lumen. This line clearing procedure can be programmed to be performed periodically.

[0185] FIG. 41 shows two balloon openings 4102 and 4106 on different sides of the catheter, and the filter 4104 covers only one of the openings. Alternatively, FIG. 42 shows an embodiment similar to the embodiment of FIG. 41, except that two openings 4204 and 4206 where the filter 4202 covers only one of the openings may be arranged side by side.

[0186] FIG. 43 shows an embodiment of the present invention where the filter 4302 covers a larger opening 4304. A larger opening may be desirable in order to obtain a more accurate pressure measurement value from the balloon. Furthermore, adding the filter 4304 can enable a larger opening due to the additional integrity that the filter, and optionally its adhesive means, provides to the region of the catheter around the opening 4304.

[0187] FIG. 44 shows an embodiment of the present invention where the filter 4402 is attached to the catheter shaft via a heat shrink tube segment 4404. This enables a hermetic seal between the filter and the catheter while ensuring that the catheter opening 4406 remains transparent.

[0188] Figure 45 shows an embodiment similar to the embodiment in Figure 44, where the catheter shaft is reduced below the balloon region. This allows the balloon to be deflated without causing inflation of the catheter to which the filter is attached. The filter 4502 is attached to the catheter shaft via a heat-shrinkable tubing segment 4504. This allows for an airtight seal between the filter and the catheter while ensuring that the catheter opening remains clear.

[0189] Figure 46 shows an embodiment of the present invention in which the filter 4602 is attached to the inside of the catheter at the opening.

[0190] Figure 47 shows an embodiment of the present invention in which the balloon has two access lumens 4702 and 4704. In this embodiment, the balloon catheter has two lumens that are in fluid communication with the balloon. In this embodiment, openings 4702 and 4704 can each access separate lumens of the catheter or the same lumen. In embodiments in which they access separate lumens, balloon inflation, deflation, and pressure measurement can be performed through either lumen. For example, pressure measurement can be performed through the lumen that is in fluid communication with opening 4702 until the accumulation of fluid in the lumen adversely affects the pressure measurement, or until a set period of time has elapsed. At this point, gas can be introduced into the lumen that is in fluid communication with opening 4702 and fluid can be removed from the lumen. Simultaneously, gas can be drawn from the balloon through the lumen that is in fluid communication with opening 4704. The reverse can also be done - fluid can be introduced into the lumen that is in fluid communication with opening 4704 and removed from the lumen that is in fluid communication with opening 4702. In this way, the liquid can be removed from the lumen communicating with opening 4702, and pressure measurement can be resumed through that lumen. This line clearing procedure can be programmed to be performed periodically. Openings 4702 and 4704 are shown opposite each other here, but the openings may be offset from each other.

[0191] Figures 48 and 49 show two different pressure balloon designs, but any suitable design and / or shape may be used. Depending on the balloon material, balloons can be manufactured in various ways. Some materials are suitable for blow molding, while others are suitable for dip molding. Other manufacturing techniques, such as resistance heat sealing, can also be used. Figure 48 shows an example of a blow-molded balloon. Figure 49 shows an example of a dip-molded balloon.

[0192] Some examples of materials that can be used to manufacture balloons include urethane, polyurethane, polyethylene, nylon, polyvinylidene fluoride, or any other suitable polymer or other material, or any combination of materials.

[0193] Balloon coatings can also be used to reduce the fluid permeability of balloons. Examples of such coatings include poly(p-xylylene) polymers or parylene.

[0194] In some embodiments, it is desirable to prevent 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 mentioned herein are suitable. Furthermore, biaxially oriented polyethylene terephthalate (BoPET), often branded as Mylar, can be used. Alternatively, metallized polymers or other suitable materials may be used.

[0195] In some embodiments, a sensing Foley catheter is configured to report the presence of water droplets or other obstructions in an air-filled lumen (such as a pressure lumen) and subsequently process or break down the droplets. Particularly in hypothermic settings, moisture in an air lumen can condense to form occlusive water droplets. Water droplets in an air-filled lumen (or bubbles in a water-filled lumen) can disrupt or complicate the pressure signal due to the surface tension of the water. Therefore, the pressure-transmitting lumen in some embodiments of the disclosed technology may include hydrophilic features (such as a coating on the wall of the lumen itself, or hydrophilic fibers extending along the length of the lumen) to allow moisture to escape from the lumen in order to maintain an uninterrupted, continuous air channel. In some embodiments, a hygroscopic composition (e.g., silica gel) can be used along the air injection line or within the air injection lumen itself to capture water or moisture. In some embodiments, the hygroscopic composition can be incorporated into the catheter so that the air injection circuit does not need to be modified to replace this material.

[0196] In some embodiments, dry air or gas may be used in the pressure tube lumen and pressure balloon to prevent moisture buildup.

[0197] In some embodiments, hydrophobic or hydrophilic coatings may be used on the pressure tube lumen and / or pressure balloon.

[0198] gas content

[0199] Another embodiment involves using a hydrophobic filter or membrane as the interface with urine in the bladder or as the inner mucosal layer of the urethra to measure the relative oxygen or other gas content of urine or tissue.

[0200] In some embodiments of the sensing Foley catheter, it is desirable to measure changes in gas content in tissue and / or urine or gas content over time. Potential gases to be measured 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, and for example, a hydrophobic membrane or other suitable membrane may be used. The pore size of the hydrophobic membrane may be about 5 microns. Alternatively, the pore size of the hydrophobic membrane may be about 3 to about 7 microns.

[0201] Figure 50 shows a sensing Foley catheter with an oxygen-permeable membrane. A retaining balloon 5002 is in fluid communication with the inflation / deflation port 5010. Urine flows through the catheter via the opening 5004 and exits through port 5012, which is in fluid communication with the opening 5004. A pressure-sensing balloon 5006 is in fluid communication with the lumen 5014. A membrane 5008 covers the opening at the distal end of the catheter, which is in fluid communication with the lumen 5016.

[0202] Figure 51 shows a sensing Foley catheter with an oxygen-permeable membrane similar to that shown in Figure 50, except that the membrane 5108 is located between the pressure-sensing balloon 5106 and the retention balloon 5102. The urine opening 5104 can be positioned anywhere distal to the retention balloon 5102.

[0203] Figure 52 shows an embodiment of a sensing Foley catheter in which a membrane 5204 is incorporated into a gas-sensing balloon 5202. In this figure, the gas-sensing balloon 5202 is distal to the pressure-sensing balloon 5206, but another embodiment in which this is not the case is shown in Figure 53. The gas-sensing balloon 5202 may be made of silicone, polymer, or any other suitable material.

[0204] The membrane material may be similar to the hydrophobic membrane materials described in other embodiments of this specification. The membrane permits the passage of gases, or specific gases, but not liquids such as urine. In this way, gases can pass through the membrane and enter the catheter in order to measure the gas content of tissue and / or urine, and / or the change in gas content over time. The gases to be measured include oxygen, nitrogen, carbon dioxide, or other gases.

[0205] The catheter can be placed in the patient such that the membrane is in either the bladder or the urethra. Here, the membrane is shown on a sensing Foley catheter with a pressure-sensing balloon, but the gas-permeable membrane can be placed on any indwelling catheter, including those in blood vessels or other body cavities. The membrane may be in direct or indirect contact with fluids, gases, or body tissues.

[0206] Figure 54 shows a controller for controlling the measurement of oxygen or other gases. The controller is generally external to the patient and is connected to the catheter via a port, such as port 5016. The controller can also control the pressure Foley function or other functions of the Foley sensing catheter.

[0207] The gas measurement controller 5402 is shown here along with the display of the catheter 5404 and the gas transfer membrane 5406. The gas measurement controller 5402 includes air or gas, an inlet 5408, air or gas, an exhaust 5410, a pump 5412, an oxygen, or other type of sensor 5414, and a check valve 5416.

[0208] In this embodiment, the pump 5412 periodically pushes small amounts of air or other gas through the tube into the catheter. The air passes through the membrane "window" 5406, and the oxygen content of the air changes based on the oxygen content of the mucosal lining (if the gas transport membrane is in the urethra) or urine (if the gas transport membrane is in the bladder). Further downstream (returning to the gas measurement controller box 5402), the oxygen percentage of the air is measured using an optical fiber or other type of oxygen sensor. The pump may operate only briefly to allow the air to equilibrium with the tissue / fluid within system time.

[0209] The check valve 5416 helps to limit the mixing of air that has passed through the system with outside air or air from a previous measurement interval.

[0210] The measured oxygen or other gas content may be very low. Measurements may represent either absolute or relative gas levels. For example, gas measurement controller readings may display a patient's relative oxygen content over time to indicate changes in the patient's condition.

[0211] Figure 55 shows a schematic diagram of how a gas measurement controller interacts with a catheter to measure the amount of gas in urine or patient tissue. The catheter 5502 includes a urine drainage lumen 5504, and gas measurement lumens 5506 and 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 the carrier gas has passed through the gas transfer membrane. The level of oxygen or other gas in the drainage gas is measured to determine the oxygen level or change in oxygen level in the patient's urine and / or tissue. The incoming gas measurement lumen 5506 may be open to the atmosphere or other source, or it may be a closed system, so that the gas in lumens 5506 and 5508 circulates continuously, and changes in gas content can be easily determined over time. That is, the air or gas inlet 5408 and the air or gas exhaust 5410 in Figure 54 may be fluidly connected to each other.

[0212] If the incoming gas measurement tube lumen 5506 is open to the atmosphere, the pump can be operated intermittently to extend the time it takes for the gas in the measurement tube lumen to equilibrate across the entire membrane surface. This increases the intermittent concentration of the measured gas, enabling more sensitive measurements.

[0213] The pump can run continuously or intermittently, regardless of whether the system is closed or open, but running it intermittently in open system mode allows for more sensitive measurements. In closed system mode, the measured gas in the system equilibrates with the gas levels in the urine, body fluid, or tissue being measured, which may result in a clearer trend.

[0214] In this embodiment, the ureteral lumen and the gas measurement lumen are separate. However, as shown in Figure 56, the gas transport membrane may be located between the ureteral lumen and the gas measurement lumen, and the gas transport membrane 5602 is in fluid communication with the ureteral lumen.

[0215] Figures 57A and 57B show embodiments of the gas measurement add-on component. The gas measurement component 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 component 5702 includes a hydrophobic filter 5704, which may be made of a material disclosed elsewhere in this specification. 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 near the filter 5704 comes into equilibrium very rapidly with the gas in the urine in the drainage system. Figure 57B shows the path of the airflow before and after the filter 5704. The gas outlet lumen 5708 is in fluid communication with a controller (not shown here) that analyzes the gas in the lumen for the gas of interest. The gas inlet lumen 5706 may be open to the atmosphere, another gas, or may be in a closed loop with the gas outlet lumen 5708 in the controller. The controller may be the same controller used to measure urine output as described elsewhere in this specification, or it may be a separate controller. Lumens 5706 and 5708 may be incorporated into the drainage tube 1001, or they may be separate. The gas measurement component 5702 may be a separate component as shown herein, or it may be incorporated into the vent barb 1016. Alternatively, the gas measurement component 5702 may be located somewhere in the system.

[0216] Detection / determination of specific conditions

[0217] Figure 58A shows a table listing parameter combinations that enable fingerprinting or signatures (combinations of parameters) for different indicators of AKI (prerenal, endogenous, and obstructive). Furthermore, fingerprinting or signatures may exist regarding the timing of parameter changes, and the cause of AKI may also be identified (for example, it is plausible that some parameters of endogenous AKI caused by glomerulonephritis and endogenous AKI caused by acute tubular necrosis change rapidly). In addition, this multiparametric approach may facilitate the selection of effective treatments for AKI because different causes of AKI have different effective treatments (for example, recombinant alkaline phosphatase is effective in treating endogenous (septic) AKI but not in treating non-septic AKI).

[0218] Figure 58B shows a table listing parameter combinations that enable fingerprints or features (combinations of parameters) of different indicators of sepsis, AKI, and acute respiratory distress syndrome (ARDS). These features include increases, decreases, or both of various patient parameters, such as urine output, heart rate, respiratory rate, body temperature, stroke volume, cardiac output, and abdominal perfusion pressure. Abdominal perfusion pressure is calculated by subtracting intraperitoneal pressure (IAP) from mean arterial pressure (MAP). Mean arterial pressure is equal to 1 / 3 of diastolic blood pressure (DP) + pulse pressure (PP). (Pulse pressure is equal to systolic pressure minus diastolic pressure.) In short, MAP = DP + 1 / 3PP

[0219] Other patient parameters can also be used. One, some, or all relevant parameters can be used by the controller to communicate diagnoses and risks to the user or another device. Patient parameters captured by the sensing Foley catheter system can be used alone or in combination with parameters acquired elsewhere, such as information from EKG, blood pressure measurement devices, and EMR.

[0220] The sensing Foley catheter system provides real-time, automated, and accurate physiological parameter monitoring for the early detection of various medical conditions. By utilizing real-time multivariate (point values) and time-series (trend) analysis of these high-frequency data streams and informing machine learning-based models, highly sensitive physiological features for early sepsis onset (or other medical condition determination) can be developed. This enables early diagnosis and intervention, improving clinical outcomes. Features related to data on physiological changes occurring before and / or during the onset of a specific medical condition strengthen relevant parameters and weaken less relevant parameters, building or breaking connections. This allows the controller to use algorithms to distinguish medical conditions from each other and differentiate them from normal and other medical conditions.

[0221] Some embodiments of the present invention allow for the measurement of urine output immediately after a patient is administered a diuretic. This type of test is a powerful indicator of whether a patient with AKI will progress to a more severe stage or die. If a patient's urine output increases after administration of a diuretic, this indicates that the patient is less likely to progress to a more severe stage of AKI. If a patient's urine output 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. The present invention allows for the measurement of urine output rapidly and accurately in real time. Therefore, the response to diuretics can be detected more quickly (in minutes rather than hours) than with conventional urine measurement techniques.

[0222] This test can be automated with a controller that delivers a controlled dose of diuretic, and then monitors urine output for several minutes or hours, preferably several minutes. The diuretic given may be furosemide, or other suitable loop diuretic or other diuretic. Diuretic administration and data collection can be carried out 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.

[0223] In addition to detecting AKI, the present invention can detect urinary tract infections (UTIs) as indicated by decreased oxygen pressure and carbon dioxide levels, increased specific gravity, and relatively stable urine output and conductance. UTI detection can be achieved in the absence of AKI, and possibly in the presence of AKI, by combining unique UTI fingerprints in urine. Distinct features of a unique UTI can inform clinicians of the presence of a UTI.

[0224] In addition to detecting AKI and UTI using the parameters described, these parameters may also be used in conjunction with readings of intraperitoneal pressure (IAP), respiratory rate (RR), heart rate (HR), cardiac output (CO), relative output (RSV), body temperature (Temp), pulse pressure (PP), urinary conductance (UC), urine volume (UO), and / or stroke volume (SV) (already used to detect conditions such as intraperitoneal hypertension (IAH)), abdominal compartment syndrome (ACS), and sepsis. Adding IAP, RR, HR, CO, RSV, Temp, PP, UC, UO, and / or SV measurements to the algorithms described herein may improve the sensitivity and specificity of detecting AKI or UTI. On the other hand, adding the measurements obtained by the present invention to 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 the treatment of trauma and burns.

[0225] In addition to absolute measurements of IAP, RR, HR, CO, RSV, temperature, PP, UC, UO, gas concentration, and / or SV, trend data of these parameters can also be used to detect IAH, ACS, sepsis, or other conditions. For example, the slope over time of the values ​​of these parameters, and / or the variation over time of the values ​​of these parameters can also be used. Another example of using data trends is the use of pulse pressure waveform analysis and pulse wave velocity (or pulse wave propagation time). Pulse wave propagation time can be determined by acquiring cardiac signals such as EKG from the lead wires of a sensing Foley catheter, and determining the time it takes for the pulse wave pressure signal to reach the bladder. Multiple parameters and / or trends of parameters can be used to determine the presence of IAH, ACS, sepsis, or other conditions.

[0226] Examples of using trend data include the following:

[0227] A decrease in UO (unclear oxygen) with stable vital signs (unless otherwise) may indicate acute kidney injury. A decrease in cardiac output may indicate renal ischemic disease. A sharp increase in urine output with stable vital signs may indicate toxic acute kidney injury.

[0228] An increase in respiratory rate accompanied by a decrease in stroke volume may indicate pulmonary embolism, bleeding, or a decrease in other volumes.

[0229] An increase in respiratory rate with stable vital signs may indicate an impending airway obstruction.

[0230] A decrease in respiratory rate when other parameters are stabilized may indicate an overdose of narcotics. This is a major problem in patient management analgesia.

[0231] An increase in intraperitoneal pressure (IAP) and urine output at a stable stroke volume setting can sometimes be an indicator of urgent fluid overload.

[0232] A decrease in unacid volume (UO) and an increase in intra-aortic platelet (IAP) accompanied by a decrease in cardiac output can be indicators of cardiopulmonary dysfunction. This may be due to conditions such as fluid overload or sepsis.

[0233] The present invention can be used in various hospital environments (e.g., emergency rooms, operating rooms, intensive care units, wards). The device can be used at any time to monitor the progression of AKI and whether the AKI is improving or decreasing. Its algorithm functions to alert clinicians to newly developed cases of AKI or changes in the status of AKI. To detect the onset of AKI, the device may be placed before kidney injury occurs (e.g., in a patient undergoing cardiac surgery to detect whether kidney injury will begin during the surgery). It may also be placed if kidney injury is already present to detect the extent of the damage at that point. The device can also be used to monitor the response to treatment / therapeutic interventions (e.g., renal replacement therapy, fluid resuscitation).

[0234] Alternative Embodiments

[0235] Embodiments of this technology may also report patient movement in the detection or diagnosis of seizure disorder. In this embodiment, pressure fluctuations may activate an EEG or recording device to enable intense monitoring periods during an episode suspected to be a seizure. Furthermore, or alternatively, pressure sensors, acoustic sensors, or other sensors may be used to detect bowel activity, including peristalsis, patient movement, seizure functional activity, patient tremors, cough frequency, cough severity, sleep duration, sleep quality, speech detection, and patient adaptability (movement or lack thereof), which can alert healthcare providers if the patient is not moving and needs to change direction or turn. This movement-related information may also be relayed to a hypothermia device, drug delivery device, or other device to control or mitigate seizure activity, tremors, and / or cough.

[0236] In some embodiments, a sensing Foley catheter is configured to report the presence of water droplets or other obstructions in an air-filled lumen (such as a pressure lumen) and subsequently process or break down the droplets. Particularly in hypothermic settings, moisture in an air lumen may condense to form occlusive water droplets. Water droplets in an air-filled lumen (or bubbles in a water-filled lumen) can disrupt or complicate the pressure signal due to the surface tension of the water. Therefore, the pressure-transmitting lumen in some embodiments of the disclosed technology may include hydrophilic features (such as a coating on the wall of the lumen itself, or hydrophilic fibers running along the length of the lumen) to allow moisture to escape from the lumen in order to maintain an uninterrupted, continuous air tunnel. In some embodiments, a hygroscopic composition (e.g., silica gel) can be used along the air injection line or within the air injection lumen itself to capture water or moisture. In some embodiments, a hygroscopic composition can be incorporated into the catheter, eliminating the need to maintain an air injection circuit to replace this material.

[0237] In some embodiments of the disclosed technology, as described in more detail above, air may be intermittently (and automatically) injected into and extracted from the pressure-sensing balloon to keep the balloon in a constant, optimally primed state. In the case of absorbent fibers or hydrophilic coatings within the lumen, the extraction of air may also contribute to removing and capturing water from the insufflation tube. In the example of a liquid-filled lumen, hydrophilic fibers or hydrophilic coatings on the inside of the pressure lumen offer similar advantages in enabling this lumen to handle air bubbles. In this example, air bubbles may distort the signal, but the hydrophilic coating within the catheter lumen relaxes the surface tension at the air-water interface.

[0238] Furthermore, custom extrusions and lumen shapes may also be used to prevent occlusion in the case of lumens filled with liquid and / or air. In some embodiments of this technology, for example, a Foley catheter may have a lumen with a star-shaped cross-sectional profile. Such lumens are generally unaffected by occlusion by water droplets, as water droplets tend to condense on themselves and move away from the hydrophobic wall. This behavior tends not to fill the cross-sectional space, leaving the vent open around the water droplets and allowing communication with the sensor. The same logic applies to bubbles in water within a hydrophilic star-shaped water lumen. In this example, the hydrophilic liquid seeps into the wall, allowing a continuous column of water to eliminate bubbles from the center of the lumen. The same is true for hydrophobic liquids within a hydrophobic lumen. In some embodiments, the catheter may include an air channel and a sensor incorporated into the catheter itself, or a fluid lumen that can return pressure to the sensor.

[0239] The drainage tube is a multi-lumen tube that houses the urinary drainage line, pressure lumen, and thermocouple wire, with one end connected to a barb and the other end to a controller.

[0240] Foley catheters can be extruded using BaSO4 or fitted with radiopaque markers for fluoroscopic observation.

[0241] The thermistor at the tip of the catheter can be fixed in place using a variety of extrusion profiles and assembly techniques.

[0242] In some embodiments, the sensing Foley catheter may 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, a device-holding balloon, or a balloon that fluidly communicates with the pressure sensing balloon) that can be inflated and optically analyzed to determine a blood vessel in the bladder or urethra. This compresses and blanches a blood vessel, stopping blood flow. This approach provides a measure of perfusion pressure in the tissue adjacent to the pressure delivery balloon, such that it reflects both systemic blood pressure and vascular resistance. This embodiment of the perfusion pressure device can be used to provide early detection or monitoring of various acute or emergency medical conditions such as sepsis, shock, and hemorrhage, and may be particularly advantageous for detecting these conditions at an early stage. In predicting sepsis, embodiments of the invention may be able to better predict sepsis by receiving white blood cell count information.

[0243] Along with the general methodological aspects of intermittent inflation within lumens, body cavities, or body tissues to provide compression of the vascular system, other modalities may also be used to detect that tissue is blanched or ischemic. Embodiments of this apparatus and related methods can also be used to detect perfusion pressure in other areas of the body using intermittently inflatable members and to optically detect blood flow or the presence of blood.

[0244] Tissue perfusion information may be provided by sensors positioned on the catheter shaft so as to contact the urethral wall when the catheter is in place. These sensing techniques include microdialysis, pyruvate, lactate, pO2, pCO2, pH, perfusion index, near-infrared spectroscopy, laser Doppler flowmeter, urethral capnography, and orthogonal polarization spectroscopy. Any of these tests are performed on the urine or the bladder wall itself to produce a tissue perfusion measurement.

[0245] Another embodiment of the sensing Foley catheter system includes an embodiment of a cleaning mechanism that includes a device and / or port for positive airflow near the starting point of the drainage line. Positive airflow facilitates drainage by forcing urine into the drainage line. The positive airflow 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.

[0246] In some embodiments, the urine removal mechanism includes a coating on the inside of the urine drainage tube to reduce surface tension and facilitate drainage. In one embodiment, the coating is a hydrophobic polymer including, but not limited to, PTFE or FEP.

[0247] In yet another embodiment, the cleaning mechanism includes a tubular hydrophobic vent filter that can be inserted into the drainage lumen of the device so that air is discharged along its entire length. Segmented hydrophobic vents can also be incorporated at regular intervals to ensure that air is discharged from the tube as the tube passes through these areas. In this embodiment, the hydrophobic vents are spaced at least 1-2 feet apart to prevent the vents from being submerged in urine. By providing surplus, multiple vents / filters prevent failure of one filter / vent due to water ingress. In an ideal configuration, the vents are made of PTFE or ePTFE material and are secured with barbs or grommets to the tube at intervals for ease of manufacture. In an alternative embodiment, the vents take the form of slits or helices extending along the length of the drainage tube, thereby allowing air to escape from the tube at any point. This prevents the drainage tube from being position-dependent when preventing and / or eliminating airlocks.

[0248] In another embodiment, airlocks are prevented by an expandable drainage tube that prevents air pockets from forming in the higher part of the tube and urine from accumulating in the lower part. The expandable tube prevents air pockets from forming in the higher part of the tube and urine from accumulating in the lower part by keeping the tube as straight as possible between the urethral catheter and the collection bag. In one embodiment, the expandable drainage tube consists of multiple expandable sections that can be extended or folded to match the distance from the patient to the collection bag. In another embodiment, the drainage tube is pleated to form an accordion and can be extended, folded or deformed as needed. In yet another embodiment, the tube is coiled. In yet another embodiment, the drainage tube is retractable by a spring coil that winds the tube around a wheel to achieve the appropriate length.

[0249] Relative cardiac output and relative tidal volume are also calculated based on the deflection of pressure sensors and / or other force gauges. When sampled at a sufficient frequency (e.g., 1 Hz or higher), respiratory deviation can be quantified relative to the amplitude of the displacement during catheter placement. Larger displacements are generally associated with heavier breathing, or with higher baseline drift settings and higher peritoneal pressure. Small peaks in the oscillatory respiratory wave caused by cardiac inflation can also be tracked using faster sampling rates (e.g., 5 Hz or higher), and the amplitude of this wave can be used in a relatively constant peritoneal pressure setting to determine relative cardiac output in a known stable peritoneal pressure, absolute output, and / or cardiac output setting.

[0250] As perceived by the embodiments of the disclosed technology, intra-abdominal pressure or bladder pressure may also be used to detect the level of patient movement (e.g., which may vary between substantially no movement and a high level of movement) and to report the level of movement to the healthcare provider. Short bursts of peaks and valleys in bladder pressure activity serve as a surrogate for body movement, as such a bladder pressure profile is a strong indicator that the patient is using their abdominal muscles to, for example, sit up or get out of bed. This embodiment may be particularly beneficial for patients at risk of falling. In patients at risk of falling, the healthcare provider may be notified that the patient is sitting and respond accordingly. Alternatively, the device may be used to report patient inactivity and / or lack of patient movement.

[0251] The pulse oximeter element enables the determination of blood oxygen concentration or saturation and can be positioned anywhere along the length of the catheter in the urethra. In some embodiments, one or more sensors are positioned within the tube of the device to ensure access to the urethral mucosa. This technique allows healthcare providers to depressurize the bladder with a urethral catheter and acquire pulse oximetry data in a reproducible and accurate manner. The power supply for pulse oximetry can be incorporated in the urine collection container or within the catheter itself. In some embodiments, the pulse oximeter is reusable and the catheter interface is disposable, in which case the pulse oximeter is reversibly attached to a disposable catheter and removed when oxygen measurement is no longer needed. Embodiments of the sensing Foley catheter may include an optically transparent or sufficiently transparent channel for the oxygen measurement signal, such as a fiber optic cable, a transparent window, and an interface for a reusable oxygen oximeter. This method and apparatus for urethral pulse oximetry may be used in combination with any of the other embodiments detailed herein, or as a standalone apparatus.

[0252] To prevent infection, antimicrobial coatings or materials impregnated with antimicrobial compounds can be used on sensing Foley catheters. Examples of antimicrobial coatings / materials include silver, silver citrate, parylene, or other suitable materials.

[0253] Pulmonary volume variability may also be determined by detection in a Foley catheter system to assist in assessing the presence or risk of heart failure. Decreased left ventricular function leads to increased pulmonary volume (PBV) or decreased pulmonary volume variability. PBV variability is defined as the change in PBV over time during the cardiac cycle. PBV can be determined as the product of cardiac output and pulmonary transit time (PTT). Cardiac output can be determined as the product of stroke volume and heart rate, where stroke volume is the region below the flow-time curve for one cardiac cycle. Pulse transit time can be obtained by examining the delay between the QRS complex of the EKG and the appearance of the bladder signal. The EKG signal can be obtained from a separate EKG lead, a lead integrated into a sensing Foley catheter, a lead integrated into a catheter insertion kit, or from another location. The EKG lead can read the EKG signal from within the urine from anywhere in the system. Two lead wires can be used to more accurately determine pulse transit time.

[0254] It is known that stroke volume, ejection fraction, and PBV variability decrease after myocardial infarction, with the greatest change 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.

[0255] Data collected by the sensing Foley catheter system is stored in a database and analyzed for trend analysis and other purposes. For example, data can be collected from multiple patients, aggregated anonymously, and used to better treat, monitor, or predict future patient behavior. For instance, data collected over time regarding heart rate, respiratory rate, body temperature, infection, etc., can be aggregated and analyzed by a controller to find trends such as relationships between various parameters and outcomes. For example, specific trends in temperature alone, or in combination with other parameters, may be predictors of infection, sepsis onset, ARDS, and / or AKI. Figure 58 shows some known examples, but other currently unknown trends may emerge from aggregated patient data.

[0256] Data collected by the sensing Foley catheter system can be integrated with electronic health records (EHRs) or electronic medical records (EMRs) and / or other systems. Data collected by the sensing Foley catheter system controller can be connected directly or indirectly to the EMR / EHR system. Data from the EMR / EHR, such as patient demographic data and medical history data, can also be integrated with the sensing Foley catheter system.

[0257] Examples of data processing systems

[0258] Figure 60 is a block diagram of 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. Note that while Figure 60 shows various components of a computer system, it is not intended to represent any particular architecture or method of interconnecting the components; such details are not closely related 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 or possibly more components may also be used in the present invention.

[0259] As shown in Figure 60, the computer system 6000, which is a data processing system, includes a bus or interconnect 6002 coupled to one or more microprocessors 6003 and ROM 6007, volatile RAM 6005, and non-interconnected 6002. The microprocessor 6003 is coupled to cache memory 6004. The bus 6002 interconnects these various components, and interconnects these components 6003, 6007, 6005, and 6006 to a display controller and display device 6008, and to an input / output (I / O) device 6010, which can be a mouse, keyboard, modem, network interface, printer, and other devices well known in the art.

[0260] Typically, input / output devices 6010 are coupled to the system via input / output controllers 6009. Volatile RAM 6005 is typically implemented as dynamic RAM (DRAM) and requires continuous power to refresh or maintain data in memory. Non-volatile memory 6006 is typically a magnetic hard drive, magneto-optical drive, optical drive, or DVD RAM, or other types of memory systems that retain data even after power is removed from the system. Non-volatile memory is usually also random-access memory, although this is not required.

[0261] Figure 60 shows that the non-volatile memory is a local device directly coupled to the rest of the data processing system; however, the present invention may utilize non-volatile memory located away from the system, such as a network storage device connected to the data processing system via a network interface, such as a modem or an Ethernet® interface. Bus 6002 may include one or more buses connected to each other via various bridges, controllers, and / or adapters, as is well 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.

[0262] Some parts of the detailed explanation above have been presented concerning algorithms and symbolic representations of operations on data bits in computer memory. These descriptions and representations of algorithms are the way that those skilled in the field of data processing use to most effectively communicate their work to others skilled in the field. An algorithm is considered here, and generally, to be a consistent sequence of operations that leads to a desired result. An operation is one that requires the physical manipulation of physical quantities.

[0263] However, it should be noted that all these and similar terms should be associated with appropriate physical quantities and are merely convenient labels applied to those quantities. Unless otherwise specifically stated as is evident from the above discussion, throughout this explanation, discussions using terms such as those set forth in the following claims refer to actions and processes of a computer system or similar electronic computing device, which involve manipulating and converting 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.

[0264] The technology shown in the figure can be implemented using code and data stored and executed on one or more electronic devices. Such electronic devices store and communicate code and data (with other electronic devices internally and / or via a network) using computer-readable media such as non-temporary computer-readable storage media (magnetic disks, optical disks, random-access memory, etc.; read-only memory, flash memory devices, phase-change memory) and temporary computer-readable transmission media (e.g., electrical signals such as carrier waves, infrared signals, digital signals, optical signals, acoustic signals, or other forms of propagated signals).

[0265] The processes or methods shown in the previous diagram can be executed by processing logic that includes hardware (e.g., circuits, dedicated logic, etc.), firmware, software (e.g., performed on non-temporary computer-readable media), or a combination of both. While the processes or methods are described above in terms of several sequential processes, it should be understood that some of the described processes may be executed in a different order. Furthermore, some operations may be executed in parallel rather than sequentially.

[0266] Unless otherwise defined, all technical terms used herein have the same meaning as generally understood by those skilled in the medical field. While specific methods, apparatuses, and materials are described in this application, any methods and materials similar to or equivalent to those described herein may be used in the practice of the invention. Embodiments of the invention have been described in some detail and illustratively, but such examples are for the purpose of clarifying understanding and are not intended to limit it. Various terms are used in the detailed description of the invention to convey an understanding of the invention; it will be understood that the meaning of these various terms extends to their general linguistic or grammatical variations. Furthermore, while some theoretical considerations may have been made to facilitate the understanding of the technology, the appended claims of the invention are not bound by such theories. Furthermore, any one or more features of any embodiment of the invention may be combined with any one or more other features of any other embodiment of the invention without departing from the scope of the invention. Furthermore, it should be understood that the invention is not limited to the embodiments shown for illustrative purposes, but is defined solely by a fair interpretation of the claims appended to the patent application, including the entire scope of equivalents, each element thereof is entitled.

[0267] Some embodiments of sensing Foley catheter systems include sterilizing the collection chamber itself or other components of the system using UV light or light of an appropriate wavelength. The UV light source can be directed through the walls of the collection chamber, or it can be placed inside the collection chamber. The collection chamber can be sterilized using the UV light source when it is empty, full, or partially full. The UV light source can be used to sterilize urine as it enters the collection chamber. The UV sterilization process may occur continuously or intermittently. The UV light source can be placed anywhere within the sensing Foley catheter system. In the bladder, ultraviolet or other wavelengths of light may be used.

[0268] Spectroscopy - Spectrophotometry

[0269] Some embodiments of sensing Foley catheter systems include using optical wavelengths ranging from approximately 520 nm to approximately 650 nm to identify bacteria, red blood cells, and / or plasma / leukocytes. See the area inside the ellipse in Figure 61.

[0270] Some embodiments of sensing Foley catheter systems include combining spectrophotometric methods to identify leukocytes and bacteria, and to identify infections by identifying decreases in PO2 and / or increases in CO2.

[0271] Some embodiments of sensing Foley catheter systems include a controller that filters urine output data to compensate for increased urine output immediately after diuretic administration. Urine volume generally increases immediately after diuretic administration. However, in certain situations, it is beneficial to essentially ignore the increased urine output data associated with diuretic administration. The controller of a sensing Foley catheter system can automatically ignore urine output data associated with diuretic administration by identifying the shape of the urine output curve associated with diuretic administration and subtracting and / or ignoring the data associated with this increase. The shape of the curve is identified by the slope, length of the increase, amplitude of the increase, shape, etc. Subtracting urine output data induced by diuretics is beneficial in determining or predicting the onset of AKI. See Figure 62. For example, if urine volume exceeds approximately 2,000 mL / hour (peak), the controller can identify this as a situation in which a diuretic has been administered.

[0272] The increase in urine output caused by the administration of diuretics can be distinguished from the increase in urine output caused by clamping, or otherwise blocking, the urinary drainage tube and / or Foley catheter. When the drainage lumen is fixed, the urine volume before the increase is essentially zero or very low, e.g., less than 5 mL / hour. In contrast, when a diuretic is administered, the urine volume immediately before administration may be very low, but is likely to exceed zero, e.g., more than approximately 5 mL / hour. Furthermore, when the drainage lumen is fixed, the increase in urine output after the release of the drainage lumen is for a relatively short period, e.g., from about 30 seconds to about 5 minutes. In contrast, when a diuretic is administered, the increase in urine volume is for a longer period, e.g., from about 30 minutes to about 2 hours. Additionally, when the drainage lumen is fixed, the urine output after the release of the drainage lumen may be less than approximately 1000 mL. In contrast, under conditions where diuretics are administered, post-administration urine volume may exceed approximately 1000 mL. Using one or all of these factors in the controller, urine output can be analyzed on a time curve to determine when diuretics were administered and to subtract the increased urine output attributable to the diuretics from the urine output presented to the user.

[0273] In this way, the controller can automatically determine when to administer the diuretic. Alternatively, the controller's user interface may include a button or other user input device (touchscreen, voice control, etc.) to indicate when the diuretic has been administered. The controller then searches for the increased urine volume and subtracts the increased urine volume attributable to the diuretic from the urine volume data presented to the user.

[0274] Some embodiments of sensing Foley catheter systems 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 by conventional methods and, in combination with the IAP used to determine the controller, can determine APP. The controller can further automatically change the infusion of fluids and / or vasoconstrictors to raise or lower blood pressure.

[0275] Prevents the filter / vents from getting wet.

[0276] Some embodiments of sensing Foley catheter systems include one or more vents and / or filters to prevent negative pressure buildup within the Foley catheter from causing aspiration trauma to the bladder. The filters / vents may be located anywhere, such as at the junction of the Foley catheter and the drainage tube, or within the collection container, or within the lumen of the drainage tube or the Foley catheter itself, as described below.

[0277] In some embodiments, the filters / vents are designed to repel fluids, i.e., from hydrophobic materials. However, despite the use of hydrophobic materials, the filters / vents can still be susceptible to wetting by liquids, particularly urine. Some embodiments include larger lumens, or lumen regions, where the filters / vents are positioned to reduce the likelihood of the lumen filling with fluid due to the surface tension of the fluid. Figure 63A shows a lumen with a smaller diameter, and Figure 63B shows a lumen with a larger diameter in the vent / filter region. Note that if the vent / filter 6304 faces upward or outward, even a small lumen can wet the filter / vent with fluid 6202, while a larger lumen can reduce the likelihood of the filter / vent wetting.

[0278] In embodiments where the filter / vent is located at or near the junction of the Foley catheter and the drainage tube, once the Foley catheter is in place, the area below or near the filter / vent can be taped to the patient's leg to stabilize the Foley catheter. A larger lumen tube helps prevent the filter / vent from getting wet in this situation, especially when the vent / filter is facing away from the leg, i.e., away from the patient. In some embodiments, the vent barb may be designed so that the vent / filter faces outward when the barb or barb area is taped to the patient's leg. For example, as shown in Figure 64, the barb may be curved or attached to a curved base for better attachment and orientation to the patient's leg 6402.

[0279] In some embodiments, the barb area is extended, for example, 6 to 12 inches, to move the vent / filter further away from the patient and to allow for easy positioning of the vent / filter in a manner that prevents wetting.

[0280] In some embodiments, the vents / filters may be located at multiple positions around the diameter of the drainage lumen, either within the barb or elsewhere. Alternatively, the vents may surround all or most of the lumen. In these embodiments, a reinforcing cuff or other structure may surround the vents to provide structural integrity to the lumen. The filters / vents may also be positioned along the length of the drainage tube.

[0281] The embodiment shown in Figure 65 also prevents wetting of the vent / filter. This embodiment includes a vent pipe 6502 with an inner lumen that connects to a drainage lumen 6504 near the barb area 6506 and is vented to the atmosphere or other air / gas / fluid along the vent pipe and / or near the other end through one or more filters / vents 6508. The filters / vents may be located inside the collection container as shown in Figure 65, or in a separate location, such as outside the collection container.

[0282] The drainage lumen may be incorporated into the drainage lumen either along or within the urinary drainage lumen. Alternatively, the vent lumen may be separate from the drainage lumen and connected to the drainage lumen at a vent / drainage junction, for example, near the barb region 6506.

[0283] The embodiment shown in Figure 66 illustrates a sensing Foley catheter system having a positive pressure vent tube 6602 with an inner lumen that is in fluid communication with a urinary drainage lumen 6604 and a pump 6606. The positive pressure vent tube may include a filter 6612 along its length, either in series or at any other location. The positive pressure vent tube may include a vent at either end of the tube, anywhere along the tube, or may include multiple vents.

[0284] The pump applies negative pressure to the urinary drainage lumen and pumps the positive pressure back into the atmosphere, while the positive pressure is pumped back into the urinary drainage lumen via a positive pressure tube. Alternatively, different pumps can be used for negative and positive pressure. In this way, precise negative or positive pressure can be controlled at the junction 6608 between the urinary drainage lumen and the positive pressure vent tube. Preferably, the pressure within the junction 6608 is either slightly negative or neutral to prevent fluid flow from returning to the Foley catheter. For example, the pressure at the junction is maintained at approximately 0 mmHg. Alternatively, the pressure at the junction can be maintained at approximately -2 mmHg. Any regulator 6610 can control negative pressure relative to positive pressure by size, timing, etc. For example, a regulator (controlled by a controller) may implement a slight delay to first apply negative pressure to the urinary drainage line, and then, after a set time or once a certain negative pressure is achieved, positive pressure is applied to the positive pressure tube, eventually reaching the junction of the positive pressure tube / drainage tube. This results in a positive net pressure at the junction of the positive pressure tube / drainage tube, preventing urine from flowing into the bladder rather than out of it. Any regulator can take the form of a vent of a specific size (to reduce resistance, reduce the surface area or make the filter material denser; to reduce resistance, increase the surface area or make the filter material looser). The positive pressure vent can be connected to the urinary drainage tube lumen via a valve, such as an umbrella valve, with a set cracking pressure.

[0285] Alternatively, the positive pressure tube may be pressurized with compressed sterilizing fluid / gas / air.

[0286] Furthermore, precise control of the negative pressure on the bladder can replicate normal bladder filling and draining. For example, a neutral or zero pressure can be maintained, or a slight positive pressure can be maintained at the base of the Foley catheter for a certain period, to simulate normal bladder filling. Then, after a set period, or after reaching a specific pressure (i.e., the pressure required to maintain neutral pressure at the base of the Foley catheter), the pressure is reduced to empty or drain the bladder. This process is controlled by a controller that controls the pressure regulator, and this process is repeated to mimic normal bladder filling and draining.

[0287] In some embodiments, a valve is used at the base of the Foley catheter to better control the pressure in that region, including the pressure (negative or positive) acting on the bladder.

[0288] Furthermore, embodiments of positive pressure tubing can be used with any embodiment of sensing Foley catheter systems, including those with filter / vent configurations different from those shown herein. In addition, any embodiment of airlock prevention can be used with conventional, i.e., non-sensing Foley catheters, or other catheters or drainage tubes.

[0289] Figures 67-86 show enlarged views of the barb region X in Figure 66 to illustrate examples of different embodiments of this region.

[0290] In the embodiment shown in Figure 67, a valve 6702, such as an umbrella valve, is shown, having a cracking pressure set between the lumen of the positive pressure vent pipe 6602 and the urinary drainage lumen 6604. The valve may be a one-way valve. The vent 6704 is shown between the positive pressure vent pipe and the atmosphere. There are also configurations in which only the vent exists or only the valve exists. The opening 6706 is in fluid communication with the urinary drainage lumen 6604 and the chamber 6714 (the valve 6702 periodically shuts off fluid communication to the chamber). The chamber 6714 is in fluid communication with the lumen of the positive pressure vent pipe 6602. Periodically or continuously, positive pressure is applied through the positive pressure lumen 6702 and / or negative pressure is applied to the urinary drainage lumen 6604. Beyond this, fluid, preferably gas, flows through the valve 6702, the opening 6706 and the lumen of the urinary drainage lumen 6604. This allows the airlock or blockage line to be cleared and the fluid to be cleared from chamber 6714, thereby reducing the possibility of the vent 6704 getting wet. It also helps to clear the vent 6704 if it is wet. The cracking pressure of valve 6702 refers to the pressure difference between the positive pressure lumen 6702 and the urinary drainage lumen 6604. If the pressure in the urinary drainage lumen is lower than the pressure in the positive pressure lumen due to the cracking 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 cracking pressure may be less than approximately 1 mmHg. Or the cracking pressure may be less than approximately 2 mmHg. Or the cracking pressure may be less than approximately 3 mmHg. Or the cracking pressure may be less than approximately 4 mmHg. Or the cracking pressure may be less than approximately 5 mmHg. Or the cracking pressure may be less than approximately 10 mmHg.

[0291] The pressure in the urinary drainage tube lumen may be approximately -5 mmHg periodically or continuously. Alternatively, the pressure in the urinary drainage tube lumen may be approximately -7 mmHg periodically or continuously. Alternatively, the pressure in the urinary drainage tube lumen may be approximately -10 mmHg periodically or continuously. Alternatively, the pressure in the urinary drainage tube lumen may be approximately -15 mmHg periodically or continuously. Alternatively, the pressure in the urinary drainage tube lumen may be approximately -20 mmHg periodically or continuously. Alternatively, the pressure in the urinary drainage tube lumen may be approximately -25 mmHg periodically or continuously. Alternatively, the pressure in the urinary drainage tube lumen may be approximately -30 mmHg periodically or continuously.

[0292] The positive pressure in the positive pressure tube lumen may be approximately 5 mmHg periodically or continuously. Alternatively, the positive pressure in the positive pressure tube lumen may be approximately 7 mmHg periodically or continuously. Alternatively, the positive pressure in the positive pressure tube lumen may be approximately 10 mmHg periodically or continuously. Alternatively, the positive pressure in the positive pressure tube lumen may be approximately 15 mmHg periodically or continuously. Alternatively, the positive pressure in the positive pressure tube lumen may be approximately 20 mmHg periodically or continuously. Alternatively, the positive pressure in the positive pressure tube lumen may be approximately 25 mmHg periodically or continuously. Alternatively, the positive pressure in the positive pressure tube lumen may be approximately 30 mmHg periodically or continuously.

[0293] The vents may also, or alternatively, be located elsewhere along the positive pressure vent, for example, near the pump or as part of a pressure regulator. A second vent / valve assembly 6708 is shown in the barb of Figure 67, but this second vent / valve assembly may or may not be present. An optional thermistor 6710 and an optional pressure tube lumen 6712 are also shown. Alternatively, the positive pressure vent may be exposed to atmospheric pressure. Valves, or additional valves, may be located anywhere in the system, such as within the positive pressure tube 6602 or within the reservoir.

[0294] Figure 68 shows an embodiment of a barb region including a vent 6802, a valve 6804, and a cross-sectional area 6806 that is large enough to allow air / gas to flow freely from the vent into the urinary drainage lumen, but small enough to prevent liquid from flowing into the vent. For example, the constricted portion 6806 may have a diameter of less than about 1 mm. Or the diameter of the constricted portion may be less than about 2 mm. Or the diameter of the constricted portion may be less than about 3 mm. Or the diameter of the constricted portion may be less than about 4 mm. The length of the constricted portion is about 1 to 5 mm. Or the length of the constricted portion may be about 5 mm to 30 mm. The embodiment shown in Figure 68 may or may not include a positive pressure tube, and is shown without a positive pressure tube (i.e., exposed to the atmosphere). This embodiment may or may not include a valve. This embodiment and any other embodiment may be incorporated into the barb, or may be a separate component that can be attached to the barb or anywhere in the system (for example, along the drainage tube, preferably one-third of the way down the drainage tube closest to the patient) (via sampling or other ports).

[0295] Figure 69 shows an embodiment of a barb region including a vent 6902 and a long vent tube 6904 that allows free flow of air / gas from the vent to the urinary drainage lumen but is long enough to prevent liquid from flowing into the vent. For example, the vent tube portion 6904 may have a diameter of about 1 to 10 mm and a length of about 1 to 10 cm. For example, the vent tube portion 6904 may be longer than about 2 cm. Alternatively, the length of the vent tube portion 6904 may be longer than about 4 cm. Alternatively, the length of the vent tube portion 6904 may be longer than about 10 cm. The embodiment shown in Figure 69 may or may not include a positive pressure tube, and is shown without a positive pressure tube. This embodiment may or may not include a valve.

[0296] Figure 70 shows an embodiment of the barb region including a vent 7002 and a long, meandering vent tube 7004 that allows air / gas to flow freely from the vent into the urinary drainage lumen but is sufficiently curved to prevent liquid from flowing into the vent. For example, the vent tube portion 7004 may be a coil. The embodiment shown in Figure 70 may or may not include a positive pressure tube, and is shown without a positive pressure tube. This embodiment may or may not include a valve.

[0297] Figure 71 shows an embodiment of the barb region including a vent 7102 and a simple, meandering vent tube 7104 that allows air / gas to flow freely from the vent to the urinary drainage lumen but is sufficiently curved to prevent liquid from flowing into the vent. For example, the vent tube portion 7104 may be a tube with a baffle or mesh in its lumen. The embodiment shown in Figure 71 may or may not include a positive pressure tube, and is shown without a positive pressure tube. This embodiment may or may not include a valve.

[0298] Figure 72 shows an embodiment of the barb region 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, so that fluid under positive pressure passes through the vent 7202 via the opening 7208, through the vent tube, and into the drainage lumen. The vent tube 7204 is shown here in a coiled shape to prevent urine backflow into the vent tube, but the vent tube 7204 may be any configuration including a straight tube or a lumen incorporated into the barb region. Here, the vent 7202 is shown near the junction of the vent tube 7204 and the positive pressure tube 7206, but the vent 7202 may be 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.

[0299] Figures 73A and 73B show embodiments of a barb region including a vent 7302 and a simple, meandering vent tube 7304 that allows air / gas to flow freely from the vent to the urinary drainage lumen but is sufficiently curved to prevent fluid from flowing into the vent. Furthermore, the vent end of the vent tube 7304 can be configured, bendable, or deformable so that it faces upward after the barb region is fixed to the patient's leg. Facing the vent end of the vent tube upward reduces the likelihood of the vent coming into contact with fluid. For example, the vent tube portion 7304 may be an essentially flat coil. The embodiment shown in Figure 73 may or may not include a positive pressure tube—it is shown without a positive pressure tube. This embodiment may or may not include a valve 7306.

[0300] Figure 74 shows an embodiment of a barb region including multiple vents 7402 and an optional valve 7404. Multiple vents reduce the possibility of all vents becoming wet with urine. The multiple vents may be 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, there may be two vents, or for example three vents, or for example four vents, or for example five vents, or for example six vents, or for example seven vents, or for example eight vents, or for example nine vents, or for example ten vents. The embodiment shown in Figure 74 may or may not include a positive pressure tube, and is shown without a positive pressure tube. This embodiment may or may not include a valve.

[0301] Figure 75A shows an embodiment of a barb region 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 through an opening 7504. Furthermore, a valve, preferably a pressure-sensitive valve 7506, is located between the opening 7504 and the drainage catheter and is in fluid communication with a positive pressure source through an opening 7510. In Figure 75A, the valve 7506 is depicted as an inflatable valve such as an annular balloon (also shown in Figure 75B). The valve 7506 may be inflated via the same pressure source connected to the positive pressure tube 7502 or a separate supply source. The valve 7506 may be in fluid communication with the lumen of the positive pressure tube 7502 as shown herein, or it may be inflated via a separate positive pressure lumen.

[0302] In this embodiment, when positive pressure is periodically applied to the drainage lumen via the positive pressure tube 7502, the valve 7506 closes. This prevents air or positive pressure from reaching the bladder and purges the drainage lumen, which allows positive pressure fluid (gas or liquid) to enter. When the positive pressure in the positive pressure tube decreases, the valve opens, and urine is again discharged from the bladder. A small amount of positive pressure can be maintained in the positive pressure tube to counteract the negative pressure in the urine drainage line. If higher pressure is required to clear the airlock line, the valve 7506 is closed while flushing at higher pressure.

[0303] 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 the negative pressure in the drainage lumen, the valve automatically closes to prevent the fluid / positive pressure from being transmitted to the patient's Foley catheter / bladder.

[0304] Alternatively, a venturi can be used to control the negative and positive pressure seeping into the barb area, similar to a car carburetor.

[0305] Figures 77A and 77B show another embodiment using a more active valve system. This embodiment includes a suction chamber 7702, an adaptable portion 7704, a patient-side valve 7706, a drainage-side valve 7708, a drainage lumen inlet 7710, and pressure lines 7712, 7714, 7716, and 7718.

[0306] 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 does not inflate, so urine can freely pass through the drainage catheter 7722, the barb's drainage lumen 7720, and the drainage tube 7724. In the open position, the adaptable portion 7704 is in the neutral position. In the event of an obstruction such as an airlock, or to prevent periodic obstruction, the drainage line valve 7708 is closed by applying pressure, such as a pressurized fluid (gas or liquid), via the pressure line 7716. The adaptable portion 7704 is expanded by applying negative pressure via the pressure line 7718. The pressure line 7714 remains neutral or closed. The pressure line 7712 remains neutral, closed, or negative to completely deflate the valve 7706. This configuration effectively applies negative pressure to the drainage catheter by expanding the adaptable portion 7704 while blocking the fluid flow to the drainage line 7724. This configuration is shown in Figure 77A.

[0307] The configuration in Figure 77A lasts for only a short time, for example, about 0.5 to 1 second, or about 1 to 3 seconds, or about 3 to 5 seconds. Next, the patient-side valve 7706 is closed by applying positive pressure to the pressure line 7712, and the drainage-side valve is opened by reducing the pressure in the pressure line 7716 to neutral or by applying negative pressure to the pressure line 7716. The pressure in the pressure line 7718 is increased to neutral or decreased by applying positive pressure to the pressure line 7718. Positive pressure can also be applied to the pressure line 7714. This configuration is shown in Figure 77B. In this configuration, the fluid in the drainage lumen 7720 and drainage line 7724 is flushed with fluid (gas / liquid) through the pressure line 7714 and / or by the positive pressure applied by the reduction in volume of the adaptive portion 7704, effectively flushing the 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 adaptive portion 7704 in the neutral position.

[0308] Figure 78 shows an embodiment similar to that shown in Figure 72, but with a positive-pressure vent 7802 instead of a separate vent. The vent hole 7804 is in fluid communication with and coincides with the lumen of the positive-pressure vent 7802. The vent hole 7804 is also in fluid communication with the barb region 7808 of the urinary drainage lumen and is connected to the region 7808 by an opening 7806. Fluid / air / gas under positive pressure passes through the vent hole 7804 and through the opening 7806 into the region 7808 which is in fluid communication with the drainage lumen. That is, positive-pressure fluid / air / gas passes through the filter and reaches the inside of the barb. Wetting of the vent hole 7804 is prevented by controlling the positive pressure before and after the vent hole 7804 in the positive-pressure vent, as well as the negative pressure in the drainage lumen. In some embodiments, the pressure in the barb region 7808 of the urinary drainage lumen is close to zero. The vent 7804 may be located anywhere along the length of the positive pressure vent pipe 7802. The embodiment shown in Figure 78 may or may not include a one-way valve between the filter and the opening. Positively pressurized fluid / air / gas can pass through the vent continuously, intermittently, or sporadically. Positively pressurized fluid / air / gas passes through the vent as a stream, puff, or pulse.

[0309] Filters throughout the system, whether located in barbs, positive pressure tubing, ventilation tubing, reservoirs, or elsewhere, may be cleared using pressure. For example, a puff of pressurized air or gas may be used over the entire filter to clear or prevent it from getting wet if it is. Alternatively, a steady or intermittent flow of air or gas may be used.

[0310] Figure 79 shows an embodiment in which the region within the barb that is in fluid communication with the urinary drainage lumen has a larger volume. Fluid such as urine 2902 flows from the drainage catheter into a larger reservoir 7904 and then into the urinary drainage lumen. The reservoir 7904 is sufficiently large that it is rarely completely filled with fluid. The volume of the reservoir that is not filled with fluid is filled with air or gas. A one-way valve 7908 may also be present. Since there is always some air / gas in the reservoir 7904, the vent 7906 can be positioned so that it is in little contact with the urine / fluid in the reservoir. That is, the vent may be on the side of the air bubble in the reservoir. Multiple vents may be present to ensure that at least one vent is always in fluid communication with the air bubble 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.

[0311] Figures 80A and 80B show embodiments with a very large vent area. The vent 8002 is shown here as a large flat circle or disk, but the vent may be of any shape and size. The vent may be flat or curved so as to wrap around the barb area. The embodiments shown here are shown with one opening 8004 and a one-way valve 8006, but other embodiments may have two or more openings and may or may not have a valve. Some embodiments may have a filter surface larger than about 1 cm². Some embodiments may have a filter surface larger than about 2 cm². Some embodiments may have a filter surface of about 3 to about 4 cm². Alternatively, some embodiments may have a filter surface of about 2 to about 4 cm². Alternatively, some embodiments may have a filter surface of about 4 to about 6 cm². Alternatively, some embodiments may have a filter surface of about 6 to about 10 cm².

[0312] Figure 81 shows an embodiment with a replaceable vent. Here, a replaceable vent 8102 is shown in an embodiment with a positive pressure tube 8104 and a one-way valve 8106, but embodiments without a positive pressure tube and / or valve may also exist. The replaceable vent 8102 can be removed and replaced via a mounting mechanism such as a Luer lock, snap lock, slide-in lock, press-fit, or other suitable mechanism. Vent replacement can be performed regularly, such as once a day, or as needed (for example, when the controller warns the user that the vent is no longer functioning properly, or when the user notices that the vent has stopped working). The vent contains urine or chemicals sensitive to components of urine, and the color changes to indicate that it is wet. For example, pH-sensitive, or other chemical or attribute-sensitive paper can be used on the replaceable vent to change color and be visible to the user. The replaceable vent is disposable.

[0313] Figures 82A and 82B show embodiments in which the filter is flexible. In this embodiment, the filter 8202 may be flexible or deformable, i.e., it may be convex / concave or loose within its housing. The movement of the flexible filter 8202 helps to clear filter blockages if the filter is wet or contaminated. The movement of the filter can be controlled by positive pressure via the positive pressure tube 8204, negative pressure via the urinary drainage lumen, valve 8206, or any one or a combination of the above. Some embodiments may also include a mechanical mechanism to agitate, shake, vibrate, bend and / or move the filter 8202. For example, Figure 82A shows an example of an embodiment in which the filter becomes concave due to negative pressure in the urinary drainage lumen. Figure 82B shows the same example after positive pressure is applied to the vent via the positive pressure tube 8204. The pressure within the vent housing 8208 can be controlled by the cracking pressure of a one-way valve, or by the relative negative and positive pressures within the urinary drainage lumen and the positive pressure tube. Similar embodiments may also exist in which the filter is not flexible, but the pressure within the vent housing 8208 is controlled in a similar manner to keep the filter dry.

[0314] Alternatively, the filter (flexible or otherwise) may be wiped or scraped mechanically, either manually or automatically. Alternatively, the filter may contain chemicals that inhibit protein adhesion and / or accumulation, such as enzyme detergents. Alternatively, the filter may contain chemicals that inhibit biofilms, such as antimicrobial agents.

[0315] Figure 83 shows an embodiment with multiple stacked filters. Filters with different pore sizes can 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 can be placed between the fluid / urine and the fine-pore filter 8302. In this configuration, the liquid / urine needs to pass through the coarse filter 8302 to come into contact with the fine filter 8302. Two or more filters can be stacked in this way. They can have stepped pore sizes, similar pore sizes, or any pore size. For example, increasingly fine pore filters can be stacked so that the finer pore filters are further away from the urine / liquid. Alternatively, one or more coarse-pore filters of the same or different pore sizes can be placed between the urine / liquid and the fine-pore filters. A one-way valve may or may not be present. The pore size of the coarse-pore filter 8304 may be about 10 microns. Alternatively, the pore size of the coarse-pore filter 8304 may be about 10 to about 20 microns. Alternatively, the pore size of the coarse-pore filter 8304 may be approximately 10 to 30 microns.

[0316] Figure 84 shows an embodiment in which a fluid in a positive pressure tube continuously applies positive pressure to the barb region. The positive pressure tube is under a nearly constant positive pressure, and a fluid (preferably air / gas) continuously passes through the opening 8404. The positive pressure applied to the fluid inside the barb 8406 is controlled to prevent the fluid from flowing back into the urinary drainage catheter. That is, the negative pressure applied to the fluid inside 8406 is always greater than or approximately equal to the positive pressure applied to the fluid inside 8406. The positive pressure may be controlled by a controller and / or by making the size of the opening 8404 very small, for example. For example, the diameter of the opening 8404 may be less than about 1 mm. Or the diameter of the opening 8404 may be less than about 2 mm. Or the diameter of the opening 8404 may be less than about 3 mm. Or the diameter of the opening 8404 may be less than about 4 mm.

[0317] Figure 85 shows an embodiment with an accordion-shaped vent. The vent 8502 in this embodiment is accordion-shaped. The vent may be compressed in the direction of the double-headed arrow. This compression can remove blockages / wet, etc., from the vent. Compression can be performed manually, automatically / mechanically, and / or using pressure (negative and / or positive) within the vent area.

[0318] Figure 86 shows an embodiment with a single vent and multiple openings. In this embodiment, multiple small openings 8602 separate the urinary drainage lumen from the vent 8604. The small openings prevent the fluid from coming into contact with the vent 8604. The multiple openings can function as surplus so that if one or more openings become clogged, the others remain open. The openings can also be used to control the passage of air / gas / fluid through the vent 8604, with more holes resulting in less resistance to airflow and fewer holes resulting in greater resistance to airflow.

[0319] Any embodiment of this specification may include or may not include physiological pressure measurement. For example, the systems shown in Figures 1 and 2, Figures 67 to 86, and other embodiments may not include a thermistor or pressure lumen and may be used with a standard Foley catheter.

[0320] 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 in the barb region. At either of these locations, pressure can be measured by incorporating an additional tube or lumen that is in fluid communication with the pressure tube / drainage tube junction or the barb region at one end and with a pressure sensor or transducer at the other end. For example, this pressure measuring lumen may be in fluid communication with a controller housing a pressure sensor at one end (sensor end) and with the positive pressure tube / drainage tube junction at the other end (detection end). A pressure-sensitive membrane may be present at the detection end to prevent urine contamination of the lumen.

[0321] Airlocks may also be detected in a manner that allows for their optimal removal and / or avoidance. Using any embodiment herein, the controller may sense the response by applying a small positive or negative pressure to the urinary drainage lumen. A damped response may indicate the presence of an airlock, while a less damped response indicates a smaller airlock, since air is more compressible than urine. If an excessive airlock is detected, the controller may initiate airlock clearing, for example, by applying negative pressure to the drainage lumen.

[0322] In some embodiments, the valve may be located anywhere in the system, including within a positive pressure pipe or a reservoir.

[0323] The vent canal may be a separate tube from the drainage tube and may be inserted into the drainage lumen or even into the Foley catheter. Figure 87 shows an embodiment of a sensing Foley catheter system in which the vent canal is located inside the urinary drainage tube. This type of embodiment has the advantage of being usable with any standard drainage tube. The vent canal has a vent opening located either inside the drainage lumen, inside the drainage tube, or inside the Foley catheter. The vent canal may be slidably inserted into the drainage tube and / or Foley catheter and may be moved at any time.

[0324] In the embodiment shown in Figure 87, the vent tube 8704 opens at one end ("air end" 8708) to the vent / filter 8702 in the collection reservoir (which is open to atmospheric pressure) and at the other end ("urine end" 8710) in the drainage lumen 8706. Here, the vent tube is shown to terminate within the barb at the base of the Foley catheter, but it can terminate anywhere in the ureteral lumen, including anywhere in the drainage tube or Foley catheter. The vent tube may remain in one place or move within the system to maximize urine drainage and minimize damage to the bladder due to airlock and negative pressure in the bladder.

[0325] Figure 88 shows another embodiment of a sensing Foley catheter system in which the vent tube 8802 has a vent / filter 8804 at the “urine end” of the tube and is open to the atmosphere at the “air end” 8806 of the tube. Filters / vents may also be present at both ends. The “air end” of the vent tube can exit the drainage lumen via a Y-arm adapter, stopcock, or other standard method. The “air end” of the vent tube can exit the system from within the collection container via a channel or port incorporated into the collection container. Again, the vent tube can be used with any urinary drainage tube, including standard urinary drainage tubes.

[0326] Figure 89 shows an embodiment similar to that shown in Figure 88, with the addition of a positive pressure tube 8902.

[0327] Figures 90, 91A, and 91B show vents at different locations within a sensing Foley catheter system. In Figure 90, the “urine end” 9002 of the vent is only a portion within the drainage tube. For example, the vent may be inserted through about half of the drainage tube. Or, for example, the vent may be inserted through about one-third of the drainage tube. Or, for example, the vent is inserted about two-thirds of the drainage tube. In Figure 91A, the “urine end” 9002 of the vent is inside the Foley catheter. The location of the “urine end” of the vent is determined based on maximizing urine drainage, minimizing the effect of airlock on drainage, and minimizing negative pressure in the bladder. In Figure 91B, the vent is inside the drainage tube, connected at one end with or near the barb, and terminates about 6 to 24 inches down the drainage line. The vent may or may not include a filter or valve.

[0328] In some embodiments, after an initial amount of urine has been discharged from the bladder, the vent tube is attached to the sensing Foley catheter system.

[0329] The vent can incorporate one or more filters / vents. The vent can incorporate one or more cutouts that are in fluid communication with the lumen of the vent can and ultimately in fluid communication with the vent / filter at the collection reservoir or elsewhere. Multiple filters / vents or multiple cutouts can be located around the vent can, along the vent can, or both. The vent can include a filter, a "urine end," or ultraviolet light directed elsewhere to maintain sterility.

[0330] Figures 92A and 92B show several possible embodiments of a drainage lumen, for example, the drainage lumen 1012 shown in Figure 10A. Figure 92A shows a drainage lumen with a collapsible / expandable portion 9202. The portion 9202 is manufactured from a material with a lower durometer than the rest of the drainage lumen and collapses or expands depending on the internal pressure. The lumen collapses to a lower internal region / volume at lower or negative pressures and expands at higher or positive pressures. The airlock may be reduced by this change in lumen volume at different pressures. This type of lumen can be incorporated into any of the embodiments herein.

[0331] Figure 92B shows an embodiment of a drainage lumen containing two lumens. The inner lumen shown here is the negative pressure / urinary drainage lumen 9204. The outer lumen is the positive pressure lumen 9206. Between the two lumens is an opening 9208. The opening may or may not contain a filter membrane. The two lumens may be concentric or adjacent, as shown here. The positive pressure lumen serves essentially the same purpose as the positive pressure vents shown elsewhere in this book. Positive pressure acts on the positive pressure lumen 9206 continuously or periodically, as negative pressure acts on the drainage lumen 9204, resulting in clearance of the drainage lumen 9204.

[0332] Figures 93A to 93E show another embodiment of the 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 foldable. When the positive pressure lumen is expanded, it partially or completely blocks the drainage lumen. When the positive pressure lumen is folded, the drainage lumen is substantially open, and fluid can flow freely through it. Figure 93A shows the drainage lumen in a closed state near the patient side of the drainage tube. Figure 93B shows the drainage lumen in a closed state further away from the patient. Figure 93C shows the drainage lumen in an open state.

[0333] Figure 93D shows a longitudinal view of the drainage tube in a closed state. Figure 93E shows a longitudinal view of the drainage tube in an open state. As shown in Figures 93C and 93E, in the open state, the positive pressure lumen 9304 folds down and does not substantially obstruct the drainage lumen 9302, allowing urine to flow freely from the body to the reservoir. When an airlock or other occlusion clearance of the drainage tube is performed, the positive pressure lumen expands, pushing urine / liquid out of the drainage tube toward the collection reservoir. The patient end 9306 of the positive pressure lumen may have a larger diameter and / or a lower durometer than the reservoir end 9308 of the positive pressure lumen. This causes the patient end of the positive pressure lumen to expand before the reservoir end expands. In this way, the drainage lumen is first blocked closest to the patient, and then almost the entire drainage lumen is filled, or a portion of the drainage lumen is filled by the remaining inflation of the positive pressure lumen. The positive pressure lumen can be inflated either on the patient side or the reservoir side of the drainage tube. One or more filters may be present along the length of the drainage lumen.

[0334] Embodiments of a sensing Foley catheter system may include the ability to measure pressure within the bladder via a pressure balloon connected to a Foley catheter, or via a pressure balloon or other pressure sensor inserted into the drainage lumen of a drainage tube or Foley catheter. See, for example, Figures 94A-94C.

[0335] Figures 94A–94C show embodiments of a sensing Foley catheter system in which the pressure sensor is in fluid communication with the ureteral lumen of the Foley catheter, but may reside on a separate catheter. The Foley catheter 9402 is shown together with the ureteral lumen 9404 and the urinary drainage opening 9406. A small pressure-sensing catheter 9408 with a pressure-sensing balloon 9410 is shown within the urinary drainage lumen of the Foley catheter. The outer diameter of the pressure-sensing catheter is small enough to fit within the urinary drainage lumen of the Foley catheter. For example, the outer diameter of the pressure-sensing catheter is less than approximately 4 mm, or less than approximately 3 mm, or less than approximately 2 mm, or less than approximately 1 mm.

[0336] The pressure sensor on the pressure-sensing catheter may be located 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, a piezoelectric sensor, a mechanical sensor, or any other type of pressure sensor. 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 it may be large enough to fill the urinary drainage lumen of the Foley catheter.

[0337] The inflated pressure-sensing balloon can fill the urinary drainage lumen of the Foley catheter, enabling better pressure measurement. The pressure-sensing balloon can be periodically or partially deflated to allow urine to flow from the bladder through the Foley catheter. The control of the pressure-sensing balloon inflation cycle can be controlled by the controller of the present invention.

[0338] Figure 94B shows an embodiment of a pressure-sensitive catheter having both an occlusion balloon 9424 and a pressure-sensitive balloon 9426. Because the occlusion balloon occludes the lumen of the urinary drainage tube, the pressure-sensitive catheter detects only the pressure between the occlusion balloon and the bladder, thereby allowing for more precise and accurate measurement of the pressure within the bladder.

[0339] The outer diameter of the inflated pressure-sensing balloon may be less than approximately 5 mm, or the outer diameter of the pressure-sensing catheter may be less than approximately 4 mm, or the outer diameter of the pressure-sensing catheter may be less than approximately 3 mm, or the outer diameter of the pressure-sensing catheter may be less than approximately 2 mm, or the outer diameter of the pressure-sensing catheter may be less than approximately 1 mm.

[0340] Figure 94C shows a standard Foley catheter with a retaining balloon 9412, a urinary drainage opening 9406, a retaining balloon port 9414, and a urinary drainage port 9416. An adapter 9418 connected to the urinary drainage port 9416 is shown. The adapter 9418 has two ports: a urinary drainage port 9420 and a secondary ureteral lumen port 9422. A pressure-sensing catheter 9408 is shown connected to the ureteral lumen port 9422. In this way, the pressure-sensing catheter is in fluid communication with the urinary drainage lumen of the Foley 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, a sensing balloon lumen, or may include other lumens. If the pressure sensor of the pressure-sensing catheter is a mechanical pressure sensor, the pressure-sensing catheter does not need to have a lumen, or the pressure-sensing catheter may have a balloon for sealing the urinary drainage lumen of a Foley catheter.

[0341] The pressure-sensing catheter may also be inserted through the urinary drainage lumen of the drainage tube.

[0342] Using a pressure sensing catheter, pressure measurements can be obtained over time and analyzed by any of the methods disclosed herein. To improve pressure measurement, the drainage port 9420 can be periodically closed or blocked. Blocking of the drainage port 9420 can be done mechanically using a stopcock or valve, or automatically using, for example, a solenoid valve connected to a controller. An advantage of this embodiment is that the pressure sensing catheter 9408 can be used with any Foley catheter to measure pressure. Furthermore, the pressure sensing catheter 9408 can be inserted and removed from the Foley catheter after the Foley catheter has already been placed in the patient's bladder.

[0343] The pressure-sensing catheter may be combined with a vent tube as shown in other figures. In this way, the pressure-sensing, urine drainage, airlock prevention, and vent components of the pressure Foley catheter system can be used with a standard Foley catheter and drainage tube. Alternatively, the pressure-sensing catheter / vent tube combination may be used with a more specialized Foley catheter and / or drainage tube.

[0344] In any embodiment including any type of airlock clearing mechanism, airlock clearing may be performed continuously, periodically (periodically or as needed), on demand, or when an airlock condition is detected. The airlock clearing mechanism prevents or mitigates the airlock. For example, an airlock clearing mechanism can reduce the airlock so that it is cleared at least every 60 minutes. Or, the airlock can be cleared at least every 45 minutes. Or, the airlock can be cleared at least every 30 minutes. Or, the airlock can be cleared at least every 20 minutes. Or, the airlock can be cleared at least every 10 minutes. Or, the airlock can be cleared at least every 5 minutes. Or, the airlock can be cleared at least every 1 minute.

[0345] In any embodiment that includes a vent, filter, or vent tube as part of the barb region or drainage tube, liquid (i.e., urine) drainage may be discontinuous, or interrupted, due to gas / air introduced into the drainage lumen through the vent / filter / vent tube. That is, the drainage lumen may alternate between liquid (i.e., urine) and gas.

[0346] In any embodiment that includes real-time measurement of urine output, real-time may mean that the reported urine output measurement is accurate within approximately one minute. Alternatively, real-time may mean that the reported urine output measurement is accurate within approximately five minutes. Alternatively, real-time may mean that the reported urine output measurement is accurate up to approximately ten minutes. Alternatively, real-time may mean that the reported urine output measurement is accurate within approximately twenty minutes. Alternatively, real-time may mean that the reported urine output measurement is accurate within approximately thirty minutes. Alternatively, real-time may mean that the reported urine output measurement is accurate up to approximately sixty minutes.

[0347] Foam in urine - Prevents foaming and / or prevents interference with measurement values.

[0348] Proteins or other components in urine can cause excessive foaming of the urine in the drainage lumen and / or collection container, which can lead to problems such as wetting of the vent / filter and urine ingress. Some embodiments of Foley catheter systems incorporate anti-foaming mechanisms.

[0349] In some embodiments, such as those incorporating a positive pressure tube, precise control of the pressure within the urinary drain can be achieved. Occasionally, a small amount of positive pressure can be applied to the drainage system (i.e., the drainage lumen and / or collection chamber) to crush any existing air bubbles or prevent their formation.

[0350] Surfactants such as silicone, simethicone, or other suitable materials may be added to the system. For example, slow-dissolving silicone capsules may be added to the collection reservoir. Alternatively, a surfactant coating may be used on the inside of the drainage lumen and / or the inside of the collection container.

[0351] Bubbles can be removed or reduced at the junction between the drainage tube and the collection container. Several embodiments are shown in Figures 95A–C. For example, the base of the drainage tube is S-shaped (like a drainpipe under a drain), and the inner diameter of the drainage tube widens near the junction with the collection container or elsewhere. The drainage tube may be bulb-shaped or conical. As shown in Figure 95C, the drainage lumen is annular. In this embodiment, bubbles are reduced by flowing the fluid along the sides of an oblique conical surface, similar to how beer is poured to the side of a glass instead of into the center to reduce foam. Here, the bubble reduction function is shown at the base of the drainage tube, but it can be located at any part of the drainage tube or system. In some embodiments, the urinary lumen may be flattened to allow urine to come into contact with the surface again. For example, the urinary drainage lumen may be flattened to less than about 1 mm. The lumen of a urinary drainage tube may flatten to less than approximately 2 mm. The lumen of a urinary drainage tube may flatten to less than approximately 3 mm.

[0352] Urine can also be forced to flow to a certain point, as shown in the inverted cone embodiment in Figure 96A. The cone may have an angle as shown here, or it may be more curved. The shape of the cone generally transitions from a small area to a large area and / or from a large area to a small area. This and other bubble reduction mechanisms may also be present in the collection container. For example, as shown in Figures 96B-D, an angled baffle can be incorporated into the collection reservoir to push the fluid down onto an angled surface. The inclined surface may extend completely to the bottom of the collection container or only partially into the collection container. Different angles, e.g., from about 10 degrees to about 80 degrees, may be used.

[0353] Angled baffles, as shown in the embodiments of Figures 96C and 96D, may also be preferable to improve the accuracy of urine volume measurement, particularly in critical care conditions where the patient's urine output is low and continuous measurement of urine output is required (mL / min or mL / sec), which is desirable for diagnosing the patient's vulnerability to the onset of AKI, sepsis, or other conditions. Accurate measurement of small urine volumes is better performed with conical or angled baffles compared to flat-bottomed baffles or cassettes because the height of the urine column is greater for a given urine volume. The ultrasonic transducer or similar transducer in the controller can more reliably measure height and provide accurate measurements of urine volume and urine output, especially when the patient's kidney is injured and urine output is low. Furthermore, angled / baffled or cassettes (urine collection chambers) can reduce measurement errors in the case of small urine volumes, as they are less sensitive to changes in the controller's tilt angle compared to flat-surface cassettes.

[0354] Figure 97A shows an embodiment of a sensing Foley catheter system in which a drainage lumen extends into a collection container / cassette so that the fluid is generally discharged into the collected fluid below the fluid level. The drainage end of the drainage lumen is cut at an angle to prevent the tube from contacting the bottom of the cassette and blocking the fluid flow. The angle cut 9724 can be about 45 degrees, about 10 to 80 degrees, or any suitable angle. Other shapes may be used at the drainage end of the drainage lumen to obtain the same result. For example, Figure 97B shows a drainage lumen in which the tube is castellated at the drainage end. The castellation 9726 may be any shape, including rounded, rectangular, triangular, scalloped, etc.

[0355] Figure 97C shows an embodiment of a sensing Foley catheter system 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 be increased or decreased while remaining the same, but in the flattened region, preferably at least one dimension is increased to increase the surface area in contact with the fluid flow. As shown in Figure 97C, the flattened region can direct the flow downward, or the flattened portion can be angled to force the fluid to flow in contact with at least one side of the inner surface of the lumen. Alternatively or additionally, an angled baffle, such as the baffle 9730 shown in Figure 97D, may be used. The angle of the baffle 9730 may be about 45 degrees, about 10 to 80 degrees, or any suitable angle. An angled baffle, or a flattened region, may be used in any of the drainage tube / lumen designs shown herein.

[0356] Figure 98A shows an embodiment of a sensing Foley catheter system in which the drainage lumen area is increased or decreased. The bulb 9832 may be incorporated into the drainage tube above the cassette, inside the cassette, or somewhere along the drainage lumen, as shown in Figure 98D. As shown in Figure 98B, the upper and lower areas of the bulb may be essentially the same, but the area below the bulb may be smaller than the area above the bulb. The reduced portion 9834 of the drainage lumen area may be relatively short, for example, portion 9834 may be about 1 mm to 10 mm in length. Alternatively, portion 9834 may be about 10 mm to 20 mm in length. Alternatively, portion 9834 may be about 10 mm in length. Figure 98C shows 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 lumen without significantly reducing the area of ​​the drainage lumen. The constricted portion 9836 may be used with or without the light bulb 9832.

[0357] Furthermore, any of the bubble reduction embodiments described herein can be used anywhere in the drainage lumen, including the drainage tube outside the cassette and the drainage tube / lumen inside the cassette. For example, Figure 98D shows an embodiment similar to the embodiment shown in Figure 98B, in which the light bulb is located inside the cassette.

[0358] Figure 99A shows an embodiment of a sensing Foley catheter system in which at least a portion of the drainage lumen is rough, causing bubbles to disperse and / or burst.

[0359] Figures 99B and 99C show another bubble reduction embodiment. In this embodiment, a grid, honeycomb, or mesh is located inside the base of the drainage tube. The mesh helps to break bubbles and is periodically compressed to clear areas of liquid, which also helps to break bubbles.

[0360] Alternatively, a flat mesh may be inserted anywhere in the system, for example, at the joint of a drainage tube / collection container.

[0361] In some embodiments, the cassette and / or drainage lumen may be vibrated continuously or intermittently to break up air bubbles.

[0362] Figures 100A-C show embodiments incorporating floating or non-floating plates to compress or break air bubbles on or near the surface of urine in a collection container. The plates may simply float on the surface and move passively up and down in accordance with the amount of urine in the container, or they may be actively moved up and down. The plates may also be fixed in place. The plates may be porous or solid. In embodiments where the plates are on the surface of the fluid, the plates may also be used for urine output measurement. The position of the plates can be determined by ultrasound, visual means (such as a camera), laser, or other methods. The volume of fluid in the collection container can be determined directly from the fluid level and can be determined by the position of the plates.

[0363] The inside of the cassette may be rectangular or of other shapes. For example, the sides of the inside of the cassette may be tapered inward towards the bottom so that there is a larger surface area of ​​urine relative to the volume of urine in the cassette. This allows for more accurate urine volume measurement with a smaller amount of urine.

[0364] Some embodiments may include a volume baffle at a set volume mark, for example, 50 mL. This volume baffle may be similar to baffle 2302 shown in Figure 23, except that it is located at a predetermined volume position. The ultrasonic signal is stronger when the upper surface of the urine volume in the cassette is at or near the volume baffle than in other cases. For example, when the upper surface of the urine volume is at approximately 50 mL (or another set volume), the volume measuring baffle can be positioned so that the upper surface of the urine volume is at or near the volume measuring baffle. The ultrasonic signal is strongest when the two surfaces (the urine and volume baffle) are close to each other or touching each other.

[0365] Some embodiments may include waveguides to help describe the inclination of the reservoir. For example, ultrasonic signals may be directed into a cylinder with flat or curved sides to direct the ultrasound toward the surface of the fluid in the reservoir so that they are reflected. The waveguide may extend into all or part of the reservoir. The waveguide may extend between the ultrasonic transducer / sensor and the surface of the fluid.

[0366] 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, in a convex curve. The convex curve helps to spread the ultrasonic signal over a wider angle, so that some of the angle is reflected from the surface of the fluid in the reservoir.

[0367] Some embodiments include a controller that uses an accelerometer to measure the incline of the reservoir and then uses the incline angle to calculate the volume of fluid remaining in the reservoir (i.e., at the lowest angle of the reservoir) after the fluid has been emptied from the reservoir. This calculated amount remaining in the reservoir can be added to the calculation of total urine output for improved accuracy.

[0368] Figure 101A shows an embodiment of a sensing Foley catheter system that includes valves at both the drainage port 10102 and the inlet point 10104 where the drainage tube connects to the collection container. This allows the controller to periodically apply pressure to the collection container to reduce air bubbles and facilitate drainage. Additionally, the inlet port valve allows the controller to stop the flow of urine into the collection container during urinary drainage, enabling more accurate measurement of urine output.

[0369] Figure 101B shows an embodiment of a collection container in which the urine overflow path is longer and / or spiral / serpentine and / or narrower. This configuration makes it difficult for air bubbles to flow into the overflow path, resulting in inaccurate measurement of urine output. The overflow path may include one or more path angles greater than 45 degrees.

[0370] Figure 101C shows an embodiment of a long 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 spiral-shaped, preventing wetting of the interface 1148. The pump interface 1148 may include a gas-permeable, liquid-impermeable filter. The length of the flow path is approximately 6–12 cm. Alternatively, the fluid path may be approximately 3–6 cm long. Alternatively, the fluid path may be longer than approximately 12 cm. Alternatively, the flow path may be approximately 3–6 cm long. Alternatively, the flow path may be longer than approximately 20 cm.

[0371] Figure 101D shows another embodiment of a long collection container in which the fluid path (shown by a dashed line) between the urine in the reservoir and the cassette pump interface 1148 is spiral, and to prevent wetting of the interface 1148. The path may include small-diameter tubes 10108 that are coiled or bundled together as all or part of the fluid path. Preferably, the spiral path is spiral in three dimensions.

[0372] Figure 101E shows another embodiment of a long collection container in which the fluid path (shown by a dashed line) between the urine in the reservoir and the cassette pump interface 1148 is spiral, preventing wetting of the interface 1148. This embodiment includes both a small-diameter tube 10108 and a spiral path molded into the cassette. The winding path may be partially molded, partially tubular, entirely tubular, or entirely molded.

[0373] The inner diameter of the small diameter tube 10108 may be approximately 1.8 to 2.0 mm. In some embodiments, the ID may be approximately 1.6 to 1.8 mm. In some embodiments, the ID may be approximately 1.4 to 1.6 mm. In some embodiments, the ID 1 may be approximately 1.2 to 1.4 mm. In some embodiments, the ID may be approximately 1.0 to 1.2 mm. In some embodiments, the ID may be approximately 0.8 to 1.0 mm. In some embodiments, the ID may be approximately 0.5 to 0.8 mm. In some embodiments, the ID may be approximately 0.2 to 5 mm. In some embodiments, the ID may be less than approximately 4 mm. In some embodiments, the ID may be less than approximately 3 mm. In some embodiments, the ID may be less than approximately 2 mm.

[0374] Some embodiments include drainage tubes having small lumen diameters. For example, in some embodiments, the lumen diameter is approximately 2 mm. In some embodiments, the lumen diameter is approximately 1 mm. In some embodiments, the lumen diameter is approximately 3 mm. In some embodiments, the lumen diameter is less than approximately 2 mm. In some embodiments, the lumen diameter is less than approximately 1 mm. In some embodiments, the lumen diameter is less than approximately 3 mm.

[0375] In some embodiments, the discharged urine can be used to "wash" air bubbles in the drainage tube or collection reservoir. Urine can be circulated through the drainage tube to increase its volume and "wash away" bubbles in the tube and / or reservoir. The controller corrects for recycled urine when calculating urine discharge.

[0376] In some embodiments, pressurized air may be introduced into the drainage tube and / or collection container. Forced air bursts and / or compresses foam and also presses the urine against the surface of the system, reducing foam formation. The cross-sectional area of ​​the drainage tube may decrease, remain the same, or increase as the drainage tube moves to a flat section.

[0377] Leveling

[0378] In embodiments where urine volume is measured in a collection container using ultrasound, it is important that the ultrasound is directed to a surface (i.e., the surface of the urine volume) at approximately 90 degrees from the ultrasound sensor. If the system is tilted by several degrees, the ultrasound sensor may not be able to sense the surface of the urine, and therefore an accurate measurement of urine volume may not be obtained. To compensate for this, the collection container or base / controller is mounted to the bed, for example, via a mounting fixture attached to a roller, so that gravity automatically levels the base when mounted.

[0379] In some embodiments, slight angles within the system are addressed by creating a “rough” surface on the urine volume in the collection reservoir. The “rough” surface provides multiple angles for ultrasonic reflection, some of which are approximately 90 degrees from the ultrasonic sensor / transducer. Roughness can be created by using air or other gases to foam the urine and vibrate the collection reservoir and / or the urine. Vibration can be achieved mechanically, ultrasonically, etc. Floating plates with a rough, concave, or convex underside can be used to float on the surface of the urine. Floating beads may remain in the reservoir when urine is discharged because their diameter is too large to exit the reservoir when urine is discharged. A mesh, a narrow, small-diameter opening, or other mechanism may be used to prevent the beads from entering the overflow area. Furthermore, as described above, angled baffles or angled-walled or tapered-walled cassettes (or urine collection chambers) can also be used to accurately measure urine volume.

[0380] Pressure balloon priming

[0381] Very small amounts of air or fluid may be required to adjust the pressure of a pressure balloon and prime it for optimal pressure sensing. For this reason, an air / gas / fluid regulator can be used between the priming fluid and the pressure balloon. The regulator allows the priming pump to operate with less air, enabling more accurate pressure balloon priming. The regulator may include foam insertion, a constriction in the fluid lumen, or other suitable regulators.

[0382] General improvements

[0383] In some embodiments, sensors in the bed, patient, or other location within the sensing Foley catheter system detect whether the patient is lying supine or not. Pressure measured in the bladder increases when the patient is not lying supine, which can negatively impact data for analysis by the controller. As a result, the controller may ignore pressure data collected while the patient is not lying supine or stop collecting pressure data during this time. Alternatively, the pressure measurement itself can be used to detect when the patient is not lying supine. A sudden increase in pressure or an increase exceeding a certain threshold may indicate that the patient is sitting, moving, or coughing. Different pressure profiles may indicate different events. Patient rolling to prevent pressure ulcers can be tracked in this manner.

[0384] In some embodiments, EKG measurements obtained from or independently obtained from lead wires attached to a sensing Foley catheter system are used to synchronize the heart rate measured via bladder heart rate with the EKG.

[0385] In some embodiments, the bed angle may be used by the controller as an input parameter to a calculation result such as IAP or APP. For example, increasing the body angle (raising the patient's head height) increases IAP. This increase may differ between healthy and unhealthy patients. As a result, determining IAP at various bed angles may provide additional information about the patient's health. Also, lowering the head level may decrease IAP, potentially stabilizing patients with high IAP.

[0386] In some embodiments, the sensing Foley catheter has at least one pressure sensor or lumen that is in fluid communication with an external pressure sensor. This pressure sensor can detect the pressure in the lumen at high speed or frequency (ideally at a speed greater than 1 Hz) and monitor physiological signals in the lumen. In some embodiments, the pressure lumen may be manually or automatically pressurized and / or depressurized while the pressure is continuously or intermittently monitored. In embodiments in which the pressure lumen includes a pressure balloon, the pressure applied to the pressure balloon by the body is monitored while the balloon inflates and / or deflates. The pressure lumen can transmit pressure waves from body cavities, one of which is the pulsation of the heart, generated by the inflow of blood into the lumen organ and / or surrounding tissues. The heartbeat and / or pulsatile pressure from the respiratory range of motion can be used to determine pulmonary and cardiovascular pressures. Furthermore, the pressure within the pressure lumen / balloon may increase beyond a threshold (i.e., 100 mmHg) and then slowly decrease within a sensing range to determine the onset of the pulse pressure, the extinction point of the pulse pressure, and / or the relative increase / decrease in pressure pulse size. The onset / extinction or relative increase / decrease of pressure pulsations detected by the pressure sensor may correlate with blood pressure, perfusion pressure, mean arterial pressure, stroke volume, stroke volume variability, respiratory effort, pulmonary barometric pressure, and other pulmonary, gastrointestinal, renal, or cardiovascular parameters. This process may resemble a blood pressure cuff, where the pressure becomes higher than blood pressure, and the pressure within the cuff slowly decreases until a blood pressure waveform (heartbeat) appears or disappears.

[0387] Figure 102 shows the pressure waveform and its decay as a pressure balloon inflates. Note that when the pressure exceeds the mean arterial pressure, the heartbeat decreases and / or disappears. If there is sufficient data to correlate the degree of decay at the relative pressure point with the mean arterial pressure, the mean arterial pressure can be derived from this relative pressure waveform. The same can be used for lung pressure and other pressures that can be sensed within the body's lumen.

[0388] In some embodiments, the pressure sensor / lumen is a capsule, balloon, or reservoir that can be slowly inflated or filled while the pressure is being monitored using an external transducer. In some embodiments, the pressure sensor is associated with a urethral catheter, such as a Foley catheter. Alternatively, the pressure sensor may be associated with a nasogastric tube, orogastric tube, or rectal tube. In yet another embodiment, the pressure sensor device and associated pressure amplification device may be fully implantable. In tissue perfusion embodiments, the pressure sensor can be inflated into the urethra or against the lumen surface, and pulse oximetry can be performed to detect blanching and / or perfusion of the lumen tissue at each pressure to determine the tissue perfusion pressure.

[0389] In some embodiments, the catheter can synergistically use multiple measured parameters to improve the quality of data analysis. In one embodiment, the catheter incorporates a sensor to capture the ECG signal internally via the urethra or bladder, or externally via a sensor located in the leg or buttocks. This signal can be used to synchronize other measured parameters (such as stroke volume) that are synchronized with the cardiac cycle with the electrical signal, and noise can be removed by obtaining an 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.

[0390] Figure 103 illustrates how to synchronize cardiogenic signals (such as bladder pressure fluctuations caused by pulses in the nearby abdominal aorta) to obtain a clean signal for analysis. Once an ECG is captured in synchronization with another cardiac signal of interest, individual samples can be synchronized, for example, using the R wave of the ECG. In this figure, the R wave of the ECG is used for alignment, multiple pressure samples are captured, and then overlaid. The median signal is then calculated by simultaneously acquiring the median of all pressure samples during the cardiac cycle. The mean can also be used. This method eliminates random noise, as external highs due to noise in one sample are offset by similarly external lows in another sample. As data points are added, the underlying signal is strengthened and ready 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 amount.

[0391] Figure 104 illustrates how respiratory pressure signals are used to inform cardiac pressure signal analysis in order to determine stroke volume variability (SVV). This method is particularly valuable for unventilated patients, i.e., patients not using mechanical ventilation. Existing techniques for measuring stroke volume, such as thermodilution and pulse contour analysis, are not affected by the respiratory cycle and therefore have limited ability to perform measurement of stroke volume variability (variability of stroke volume between inspiration and expiration). Using the luminal pressure described herein, such as an intrabladder Foley catheter, has the advantage of allowing simultaneous capture of respiratory and cardiac signals (similarly slow-moving intraperitoneal pressure). Thus, this device allows for the selection of respiratory cycles to be used for stroke volume variability analysis, as specific characteristics are better suited to the appropriate analysis (such as respiratory rate and size). In this figure, sample pressure signals captured from the bladder are shown. In the raw pressure signals above, large fluctuations are due to respiration and are selected for analysis based on, for example, wave width, amplitude, or peak value. Other characteristics not shown, including slope, area under the curve, shape, frequency, pattern, and repeatability, can be used to define a suitable wave. If a curve has amplitudes exceeding a certain value, a curve amplitude filter can be used; values ​​below that, or other specific values, are not used in the SVV calculation. The figure below shows the same signal after passing through a high-pass filter and a low-pass filter. The high-pass filter leaves the underlying cardiac signal (dashed line), and the low-pass filter leaves the underlying respiratory signal (solid line). In this example, the difference in intensity of the cardiac signal between the peaks and troughs of the respiratory signal (e.g., the inter-peak value) can be used to calculate the stroke volume variability.

[0392] Respiratory rate and other parameters may be sensed via a sensing Foley catheter, or may be sensed or acquired by any conventional or non-conventional means. Other parameters that may be collected include data collected via tidal volume, vital capacity measurement, respiratory flow parameters, vital capacity measurement, expiratory effort, inspiratory effort, etc. Any of these parameters can be used to assist in the calculation of stroke volume variability and / or other cardiac parameters.

[0393] The filters used to determine which pressure peaks are used in the SVV calculation may be based on any of the pressure curve parameters disclosed herein. Furthermore, the SVV calculation itself can be used to determine the pressure curve peaks used in the calculation. For example, SVV is typically within approximately 10%. The systems disclosed herein may include or exclude pressure curve data based on the resulting SVV calculations that fall within a specific range of values, such as approximately 10%.

[0394] SVV calculations can also be patient-specific. For example, while the peak filter of a pressure curve may be amplitude-based, the cutoff amplitude is patient-specific and may be based on the mean, average, or other parameters of that patient's pressure curve. Alternatively, the filter may be based on multiple patients, or multiple patients within a specific category, such as a particular disease state.

[0395] Signal and / or SVV calculations can also filter out patient movement and / or other artifacts such as coughing, shifting, and sneezing.

[0396] In addition, a calculated SVV of very low or absent may be an indicator of fluid overload, which may suggest appropriate treatment.

[0397] In some embodiments of the disclosed system, the patient may be prompted to breathe in a specific way. For example, based on the shape of the pressure curve (peak amplitude, frequency, etc.), the system may prompt the patient to breathe more deeply, more slowly, or normally. The resulting respiratory pressure curve can be incorporated into the calculation of SVV. This type of prompting may be performed by the system if the pressure curve is insufficient to provide SVV calculations, or for other reasons.

[0398] Figures 105A and 105B show two diagrams of the base piece of the sealing mechanism between the cassette and the controller. Typically, the base piece shown in Figures 105A and 105B connects to the cassette, and the pin shown in Figure 106 connects to the controller. However, the connector can also be installed in reverse, with the pin connected to the cassette and the base to the controller. The purpose of the sealing mechanism is to connect the lumen of the cassette to the lumen of the controller when the cassette is connected to the controller, but to seal the lumen of the cassette when the cassette is disconnected from the controller. For example, the cassette may be temporarily disconnected from the monitor / controller when a patient undergoes surgery or moves from one room to another. While the cassette is disconnected from the controller, it may be desirable to seal the lumen of the cassette to prevent contamination and to prevent urine, liquids, or gases from leaking or entering the system.

[0399] For example, lumens such as a pressure balloon lumen (pressure transducer interface 1026, etc.), a vent lumen 1150, a cassette pump interface 1148, and / or a cassette pressure interface 1150 may have connectors such as these.

[0400] The base portion 1050 of the connector is shown in Figures 105A and 105B. The base can be manufactured from a highly compressible, 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, as well as a slit 10506 of length L3. Preferably, the slit 10506 is a single linear slit, but since it is equipped with a sharp knife after the base is formed, the slit does not have a rounded edge and can be completely sealed in a relatively relaxed state. When the base 1050 is connected to a lumen, fluid cannot flow through the slit in the base.

[0401] The pin portion 1060 shown in Figure 106 includes a pin head 10604 and a pin stem 10602 containing a lumen through which it passes. The outer diameter of the pin stem 10602 is D3. The pin 1060 fits inside the slit 10506 of the base 1050, and when positioned in this manner, allows fluid to pass through the sealing mechanism. In some embodiments, L3 is approximately equal to D3.

[0402] Figures 107A and 107B show a pin 1060 inserted into a slit 10506 of the base 1050, which allows fluid to flow through the lumen and sealing mechanism of the pin.

[0403] Figure 108 shows the base portion of the sealing mechanism 1050 located on the back of the cassette, designed to snap into the opening of the controller. The base portion of the sealing mechanism shown here is connected to the pressure balloon lumen interface 10802, the vent lumen interface 10804, the cassette pump interface 10806, and the cassette pressure interface 10808 (for measuring IAP). Note that not all, some, or any of the cassette interfaces can use these types of sealing mechanisms. For example, the pressure interface 10808 for measuring IAP does not need to be sealed when the cassette is removed and may use a different type of connector.

[0404] Figure 109 shows the operation of the sealing mechanism when the cassette is connected to the controller. Cassette 1022 is shown in cross-section where one of the sealing mechanisms is installed. The base 1050 is attached to the cassette portion and is sealed when the pin 1060 is not present. The pin 1060 is connected to the controller (not shown), and when cassette 1022 is snapped into place on the controller, the pin 1060 is inserted into a slit in the base 1050, allowing fluid to enter and exit between the cassette and the controller. The connection may include a filter, shown here as filter 10902.

[0405] Figure 110 shows the approximate dimensions of an embodiment of base 1050. These dimensions may vary depending on the application.

[0406] Figure 111 shows some of the forces exerted on the base 1050 when the entire cassette is mounted. These forces are caused by the diameter of the mounting hole and the diameter of the stem 10508, and the thickness of the cassette wall and the length of the stem 10508. In addition, compressive forces may press against the base head 10504 when the cassette is installed in the controller. These forces tend to reinforce the seal of the base 1050, regardless of whether the pin is inserted into the slit. That is, based on the dimensions and shape of the base, forces are exerted on the slit, causing the slit itself to remain closed or the pin to remain closed. The forces push the slit inward. The forces push the slit inward, causing the base head 10504 to be slightly concave at the bottom (like a mushroom), spreading out at the bottom (the wider part) and compressed at the top (where the slit opening is). This is especially true when the thickness of the cassette wall is greater than the length of the stem 10508.

[0407] In some embodiments, multiple drainage lumens can be used to prevent airlock. The proximal and / or distal openings may be staggered. The lumens may be incorporated into one or more tubes and may or may not hold a siphon. 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 eight or more drainage lumens may be used.

[0408] In any of the embodiments disclosed herein, the vent can be connected to a standard or non-standard Foley catheter by attaching it to the sampling port of the Foley catheter or to any part of the sampling port drainage system of a barb near the Foley catheter. See, for example, Figure 112.

[0409] Figure 112 shows an embodiment including a venting mechanism / vent tube that can be added to any urinary drainage system including a sampling port 1004 or any other suitable port. In this embodiment, the venting mechanism 11200 can replace the sampling port 1004 with a vent in the system to avoid an airlock. 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 maintains an opening that is in fluid communication with the drainage lumen 1012 for performing the discharge function. In this figure, the sampling port is shown as part of a barb 1016, but the sampling port can be anywhere in the drainage system. Alternatively, other ports or access points can be used. This embodiment can be used with or without a vacuum pump. The vent tube may be rigid or flexible or bendable. The ventilation mechanism may include means of suspending the vent tube above the height of the bladder, for example, 1 to 10 cm above the height of the bladder. The length of the vent tube may exceed 1 cm round. Alternatively, the length of the vent tube may be greater than 2 cm round. Alternatively, the length of the vent tube may be greater than 3 cm round. Alternatively, the length of the vent tube may be greater than 4 cm round. Alternatively, the length of the vent tube may be longer than 5 cm round. Alternatively, the length of the vent tube may exceed 10 cm round. The ID of the vent tube is less than approximately 5 mm. Alternatively, the inner diameter of the vent tube may be less than approximately 4 mm. Alternatively, the ID of the vent tube may be less than approximately 3 mm. Alternatively, the ID of the vent tube may be less than approximately 2 mm. Alternatively, the ID of the vent tube may be less than approximately 1 mm.

[0410] In this figure, the vent tube 11202 is shown to terminate in the atmosphere, but the vent tube may be connected to a drainage bag as shown in Figure 11E. If a valve and a vent are present, the valve may be located between the sampling port and the vent, or the vent may be located between the sampling port and the valve. This type of ventilation mechanism can be implemented at the sampling port after an initial volume of urine has been drained from the bladder. This type of ventilation mechanism can be incorporated into a strap or patch for securing the barb to the patient's leg or another location. The ventilation mechanism / vent tube of this embodiment may have one or more small-diameter sections of length as shown in Figure 11D. For example, the section of the vent tube 11202 may be relatively long and of relatively small diameter to prevent urine from moving through the vent tube and reaching the valve and / or filter.

[0411] Instead of using the puncture mechanism 11208 together with the sampling port 1004, the puncture mechanism may be used along the tubing of the catheter or drainage tube. Alternatively, a mechanism may be used in which the port is normally closed but accepts an additional ventilation mechanism / ventilation tube. For example, a sealing mechanism pin configuration such as that shown in Figures 105-111 can be used if the base is on the catheter / drainage tube and the pin is part of the ventilation mechanism / ventilation tube, or vice versa. In some embodiments, the port 1004 may be on an add-on barb or connector piece intended to be positioned between the catheter and the drainage tube.

[0412] Figure 113 shows an embodiment including a pump / argor 11302. The pump preferably acts on the outside of the drainage tube 1012, thereby urging the fluid in the drainage tube toward the drainage bag. The pump may be a peristaltic pump, a pump with rollers, a pump that applies periodic pressure, etc. In a very simple embodiment where the pump applies periodic pressure (as schematically shown here), the ID of the drainage tube changes along its length so that the fluid flows mainly in one direction, in this case toward the drainage bag. The ID on the patient side of the drainage tube may be smaller than the ID on the drainage bag side of the drainage tube. As shown in this enlarged view, the ID may decrease or the change in ID may be gradual.

[0413] Figure 114 shows an embodiment in which the drainage tube 1012 is coiled or includes a compression section 11402. In this embodiment, slack in the drainage tube is reduced. The coil may be supported by a shape memory material or by a physical clip or some kind of holder. Preferably, the drainage tube can stretch to accommodate patient movement.

[0414] Figures 115A and 115B show an embodiment of the barb including a tube seating mechanism. The barb 11502 includes a urinary drainage tube 11504 surrounding a urinary drainage lumen 11506 and a ventilation tube 11508 surrounding a ventilation lumen 11510. Tubes 11504 and 11506 are inserted into the barb during manufacturing and seated in step 11512. This causes both the urinary drainage lumen and the ventilation lumen to open into a single inner lumen 11516 of the catheter manifold 11514, as shown in Figure 115B.

[0415] In some embodiments, the controller controls a pressure sensor on or near the barb to determine when the pressure in the barb area is not excessively negative, allowing a vacuum to be drawn into the drainage line without causing suction trauma to the bladder. The pressure sensor can also be used to determine the initial placement of the system and to ensure that the pressure in the drainage line is not negative or too negative. If the pressure in the drainage line is very low, the controller operates a valve in the urine collection reservoir or elsewhere to temporarily stop or slow urination, reducing the pressure and minimizing the possibility of bladder suction trauma.

[0416] In some embodiments, the bladder is periodically pressurized to aid in the expulsion of urine from the bladder. This can be done using a retaining balloon, a pressure-sensitive balloon, another balloon, etc.

[0417] In some embodiments, airlock clearance is performed intermittently. In some embodiments, airlock clearance is performed continuously, for example, by drawing a continuous small vacuum in the drainage line.

[0418] In some embodiments, pulse oximetry data can be collected from the patient's skin, for example, from the thigh, or from somewhere in the groin or leg.

[0419] In some embodiments, the controller manages the overall air volume and / or pressure of the system. For example, the controller may sense overpressure of the urine collection bag, which may occur if the air filter (shown as 1142 in some figures) is blocked or wet. This increases the risk of the bag bursting. If this occurs, the controller may instruct the system to do one or more things to mitigate the problem. The controller may attempt to clear the filter by blowing a “puff” of air onto it. The controller may slow down or stop urine discharge by slowing down or stopping the airlock clearance pump. The controller may instruct the pump to intermittently reverse direction to reduce pressure in the drainage bag. The controller may warn the user to modify or manually correct the drainage bag problem. The controller monitors pressure anywhere in the system to identify and, if possible, mitigate pressure-related problems. The controller can monitor pressure in the barb, within the drainage line, within the ventilation line, within the reservoir / cassette, within the drainage bag, etc. For example, the controller can control the pressure inside the cassette to empty the cassette, empty the filter, and reduce bubbles.

Claims

1. A catheter having at least one opening at or near its distal end, which is inserted into the body, A barb that is in fluid communication with the proximal end of the catheter, The drainage tube having fluid communication with at least one opening and the barb, A vent pipe that communicates with the drainage tube, A one-way valve is arranged in a straight line with the aforementioned vent pipe, A catheter system comprising: a controller controlled to apply negative pressure to the drainage tube, the controller controlled to open the one-way valve to allow air in by the direct action of the negative pressure on the one-way valve and by the action of the fluid passing through the vent tube.

2. The catheter system according to claim 1, wherein the controller is further programmed to periodically change the negative pressure such that the one-way valve is closed and fluid is prevented from passing through the vent pipe.

3. The catheter system according to claim 1, characterized in that the fluid is received through the one-way valve when opened, so that the fluid flows through the vent pipe to the drainage tube.

4. The catheter system according to claim 1, wherein the one-way valve is configured to open when the pressure difference before and after the one-way valve exceeds a predetermined cracking pressure of the one-way valve.

5. The catheter system according to claim 4, wherein the one-way valve is further configured to close when the pressure difference before and after the one-way valve falls below the predetermined cracking pressure of the one-way valve.

6. The catheter system according to claim 1, wherein the one-way valve is positioned proximal to the catheter.

7. The catheter system according to claim 1, wherein the first portion of the vent tube defines a first diameter and a first length, and the second portion defined proximal to the one-way valve defines a second diameter and a second length.

8. The catheter system according to claim 7, wherein the first diameter is shorter than the second diameter.

9. The catheter system according to claim 7, wherein the first length is shorter than the second length.

10. The catheter system according to claim 7, wherein the first length and the second length are substantially equal to the length of the drainage tube.

11. The catheter system according to claim 7, wherein the first diameter and the second diameter are equal.

12. The catheter system according to claim 7, wherein the first diameter is less than 4 mm.

13. The catheter system according to claim 7, wherein the first diameter is less than 2 mm.

14. The catheter system according to claim 7, wherein the first diameter is in the range of 0.2 to 5 mm.

15. The catheter system according to claim 7, wherein the second diameter is longer than 2 mm.

16. The catheter system according to claim 7, wherein the second diameter is in the range of 0.2 to 5 mm.

17. The catheter system according to claim 7, wherein the first length is less than 10 cm.

18. The catheter system according to claim 7, wherein the first length is longer than 2 cm.

19. The catheter system according to claim 7, wherein the first length is in the range of 5 to 10 cm, 10 to 20 cm, 20 to 30 cm, or 30 to 50 cm.

20. The catheter system according to claim 7, wherein the second length is in the range of 50 to 150 cm.

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