System for draining and analyzing bodily fluids and assessing health

Abstract

To provide systems, devices and methods for draining and analyzing bodily fluids and assessing health.SOLUTION: Systems, devices and methods for draining and analyzing bodily fluids and assessing health are described generally comprising: a pumping mechanism which is fluidly connectable at a first end to a portion of a drainage line; and a venting mechanism having a one-way valve which is fluidly connectable at a first end to a drainage catheter and the drainage line. The pumping mechanism may be configured to create a negative pressure within the drainage line when the pumping mechanism is in communication with the drainage line, and the one-way valve may be configured to open to an environment when the venting mechanism is connected at the first end, and when the drainage line is at a pressure less than an environmental pressure such that an airlock is prevented from forming within the drainage line.SELECTED DRAWING: Figure 64

Description

[Technical Field]

[0001] Cross-reference to related applications This application is related to international patent applications PCT / US2018 / 13399, filed January 11, 2018; PCT / US2011 / 043570, filed July 11, 2011; PCT / US2012 / 028071, filed March 7, 2012; PCT / US2016 / 060365, filed November 3, 2016; PCT / US2015 / 052716, filed September 28, 2015; PCT / US2014 / 044565, filed June 27, 2014; PCT / US2015 / 010530, filed January 7, 2015; Application PCT / US2016 / 060365 is related to U.S. Provisional Application No. 62 / 651,377, filed April 2, 2018, and U.S. Provisional Application No. 62 / 756,473, filed November 6, 2018, U.S. Provisional Application No. 62 / 776,388, filed December 6, 2018, and U.S. Provisional Application No. 62 / 798,365, filed January 29, 2019, each of which is incorporated by reference herein to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference.

[0002] The present invention relates to the field of medical devices. In particular, the present invention relates to devices for assisting bladder emptying, measuring urine volume and various urine parameters such as oxygen tension, urine conductance, and urine specific gravity, monitoring kidney function, analyzing urine parameters such as urine content, including the presence of infection, and tracking and / or controlling fluid administration. The present invention further relates to medical devices capable of detecting physiological data based on sensors integrated into catheters configured to reside in the urinary tract, gastrointestinal tract, rectal location, preperitoneal cavity, pleural cavity, or other body cavities. Incorporation by Reference

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

[0004] It is estimated that 10% of hospitalized and long-term care patients have an indwelling urinary catheter. Urinalysis is almost always performed on critically ill patients, and hourly monitoring of urine output is routine in ICUs. The amount of urine produced is an indicator of fluid status and renal function. However, this important indicator can be mismeasured due to numerous error factors.

[0005] The most commonly used device for bladder drainage is the Foley catheter. Its design, a flexible tube with an anchor balloon and small holes that allows urine to drain from a central lumen, has remained largely unchanged since its introduction. However, current Foley catheter designs have been shown to leave a large residual volume in the bladder, exceeding 50 mL in the supine position (see Non-Patent Document 1). One study found that the average residual volume was 96 mL in the ICU and 136 mL in the general ward (see Non-Patent Document 2). Large amounts of residual urine are also commonly found in the drainage tube connecting the Foley catheter to the drainage bag and in other locations within the drainage system.

[0006] Residual urine in the bladder and drainage tube is caused by large air bubbles (air locks) forming in the tube that block the flow of urine from the bladder to the drainage bag. Therefore, it has become routine for nurses to assist in emptying the drainage tube by manipulating it before urine volume measurement. In ICUs, where measurements are taken hourly, this is a highly repetitive and inaccurate task. There is a need for more accurate and automated urine volume measurement.

[0007] Additionally, there is an opportunity to measure and analyze urine parameters within the urine collection system.

[0008] In addition to improving urine volume measurement and urine parameter analysis, the urinary drainage catheter itself offers untapped opportunities for the sensing, collection, and analysis of additional patient parameters. [Prior art documents] [Non-patent literature]

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

[0010] Additionally, there are many types of medical devices configured to control the treatment and / or maintenance of a patient. For example, a respirator can control a patient's breathing rate, breathing volume, and / or gas mixture. An intravenous (IV) can administer fluids and / or substances, such as medications, to a patient. Other devices include those capable of drug delivery and other operations. These types of medical devices can be tightly controlled through various settings. A healthcare professional, such as a nurse, can view various patient parameters and adjust the settings of the medical treatment device accordingly. There is a need for a controller that automatically or semi-automatically controls the settings of the medical treatment device using the patient parameters. [Means for solving the problem]

[0011] Foley-type catheters, which are widely available, low-cost, and easily placed by medical professionals, can be modified and / or enhanced to provide important diagnostic information. The technology disclosed herein can provide high-resolution, previously unavailable diagnostic information, such as that provided by a Foley catheter with intraperitoneal pressure (and other) sensing capabilities.

[0012] Additionally, airlocks have been shown to significantly distort intra-abdominal pressure measurements. Bladder inactivity can also adversely affect intra-bladder pressure measurements. The techniques disclosed herein detect and eliminate airlocks in settings such as intra-abdominal pressure measurements, resulting in more complete bladder drainage.

[0013] The technology disclosed herein aims to more effectively drain the bladder, prevent and resolve airlocks in drainage tubes, and improve the accuracy of automated urine volume measurements. The disclosed technology also seeks to incorporate additional urine measurements such as oxygen tension, conductance, and specific gravity, gas pressure, turbidity, infection, and sediment to improve monitoring of fluid status, renal function, and other important patient parameters.

[0014] Also disclosed is a Foley catheter for sensing physiological data from a patient's bladder and / or urinary tract, particularly physiological data collected by high-fidelity pressure sensing and conversion to a signal suitable for processing. In some embodiments, a pressure-sensing Foley-type catheter may also be capable of sensing temperature and clinically significant analytes. Examples of physiological parameters that a sensing Foley catheter system may measure (temporal measurements and trends of values over time) include urine volume, respiratory rate, heart rate, heart rate variability, cardiac output, cardiac output variability, intra-abdominal pressure (IAP), tissue oxygenation, tissue gas content, pulse transit time, pulmonary blood volume variation, body temperature, blood constituents, and other patient parameters.

[0015] A drainage assembly according to one embodiment configured to prevent negative pressure buildup may generally comprise an elongate catheter having a first end configured for insertion into a body cavity. The catheter may include at least one opening near or at the first end in fluid communication with a catheter lumen formed therein, a drainage lumen in fluid communication with a second end of the catheter, a reservoir in fluid communication with the drainage lumen, and a vent mechanism in fluid communication with the drainage lumen and the positive pressure lumen. A valve may be disposed within the vent mechanism and configured to maintain a closed position until a first pressure level in the drainage lumen drops to a second pressure level, causing the valve to move to an open position. A vent may also be disposed in fluid communication with the valve, the vent mechanism configured to inhibit wetting of the vent from fluid in the drainage lumen; and a controller in communication with the reservoir, the controller configured to measure the amount of fluid collected in the reservoir.

[0016] In another example, a drainage assembly may be configured to prevent the buildup of negative pressure and generally includes an elongate catheter having a first end configured for insertion into a body cavity, the catheter having at least one opening near or at the first end in fluid communication with a catheter lumen formed therein. The drainage lumen may be in fluid communication with a second end of the catheter and may include a positive pressure lumen in fluid communication with the drainage lumen, a reservoir in fluid communication with the drainage lumen, and a vent mechanism coupled to the drainage lumen, the vent mechanism configured to inhibit wetting of the vent from fluid in the drainage lumen. A controller may be in communication with the reservoir, the controller configured to measure 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 the closed position to the open position when a first pressure level applied to the valve decreases to a second pressure level.

[0017] Certain patient parameters that can be measured and / or determined by the disclosed technology are influenced and / or affected by treatment of the patient by a medical treatment device. For example, patient parameters such as a patient's urine volume, respiratory rate, heart rate, cardiac output, cardiac output variation, intra-abdominal pressure (IAP), tissue oxygenation, tissue gas content, body temperature, blood constituents, etc., can be influenced and / or affected by a medical treatment. Examples of medical procedures controlled by a medical device include respiratory rate and constituents controlled by a respirator, intravenous drip rate and constituents controlled by an intravenous drip controller, drug delivery controlled by a drug delivery device or intravenous drip controller, urine volume controlled by a urine volume pump, peritoneal fluid volume controlled by a drain pump, and other procedures controlled by other medical treatment devices.

[0018] One embodiment of a system for analyzing bodily fluids generally includes an elongate catheter having an inflatable balloon positioned near or at the distal end of the catheter and further defining one or more openings adjacent to the balloon; a venting mechanism coupled to the proximal end of the catheter, the venting mechanism configured to pass air therethrough when a negative pressure is applied to the venting mechanism; a first lumen coupled to the venting mechanism and in fluid communication with the one or more openings; a second lumen in fluid communication with the balloon; a reservoir coupled to the proximal end of the first lumen and in fluid communication with the one or more openings; and a controller configured to connect to the reservoir and programmed to control pressure within the first lumen. The controller is further programmed to monitor urine volume received into the reservoir from a patient and to measure the patient's intra-abdominal pressure based in part on pressure changes in the balloon. The controller is further configured to store patient data.

[0019] In one exemplary method for analyzing one or more body parameters from a patient, the method generally includes positioning an elongate catheter having an expandable balloon positioned near or at a distal end of the catheter within a body cavity at least partially filled with bodily fluid; receiving urine through one or more openings formed along the catheter proximate the balloon; further receiving bodily fluid in a reservoir located outside the body cavity and in fluid communication with the one or more openings through the body cavity; venting air through a venting mechanism in communication with the fluid lumen when a negative pressure is applied to the fluid lumen; analyzing the amount of urine received in the reservoir via a controller programmed to control the negative pressure to the venting mechanism; measuring the patient's intra-abdominal pressure based in part on the pressure changes in the balloon; and storing one or more parameters of patient data via the controller.

[0020] Some embodiments of the sensing Foley catheter system include a loop controller that receives one or more data related to patient parameters and uses this information to control one or more medical treatment devices. The loop controller may be integral with either the device that measures the patient parameter, the medical treatment device, or both.

[0021] A pressure-measuring balloon on a catheter, such as that disclosed in International Patent Application No. PCT / US2014 / 044565 (Patent Document 1), entitled "Sensing Foley Catheter," which is incorporated herein by reference in its entirety, is one example of a device for measuring patient parameters. Additional embodiments are disclosed herein. Sensing Foley catheter systems can include pressure-measuring balloons and / or other sensors, as well as the ability to measure urine volume and composition to measure urine flow rate, IAP, respiratory rate, heart rate, cardiac output, tissue oxygenation, urine composition, temperature, and other patient parameters.

[0022] Other parameters that can be measured with a sensing Foley-type catheter include urine specific gravity and pulse pressure variation, which can be used to assist in the control of medical treatment devices such as ventilators and / or fluid and / or hydration devices.

[0023] 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. A higher reading may indicate conditions such as dehydration. A lower reading may indicate conditions such as fluid overload. Measurements may be performed using a sensor in a Foley catheter. Results may indicate increasing (in the case of dehydration) or decreasing (in the case of fluid overload) the patient's fluid infusion rate. Results may also indicate changes in ventilation parameters or medication infusion.

[0024] The variability in pulse pressure can predict the responsiveness of bodily fluids to medical treatment devices, such as ventilators and / or infusion devices. A sensing Foley catheter records the pressure waveform, and the controller can identify maximum and minimum pressure pulses that coincide with respiratory cycles. The controller can calculate the variability in pulse pressure. The variability in pulse pressure can help determine whether a patient will respond or not to fluid therapy. The variability in pulse pressure can also be used by the controller to control therapy in a feedback loop. If the variability in pulse pressure is large, the patient will need more fluid. If the variability in pulse pressure is small, less fluid will be needed.

[0025] The sensing Foley catheter system can measure cardiac activity by sensing intrabladder pressure. The sensing Foley catheter can measure not only cardiac activity but also respiratory activity. Because the patient's respiratory rate and heart rate can be close in frequency, measuring the patient's respiratory rate can distort the heart rate measurement. To overcome this challenge, some embodiments of the controller can pause the respirator at the end of one or more inspiration points and / or at the end of one or more expiration points (for only a few seconds each time, e.g., 1-3 seconds, or e.g., 1-4 seconds) so that the cardiac waveform can be captured without respiratory distortion. By capturing detailed cardiac waveforms in this manner, the controller can measure cardiac output variation (SVV), which is useful for detecting sepsis and preventing fluid overload. Alternatively, the patient may be asked to hold their breath during inspiration and / or expiration.

[0026] In another example, a catheter system may generally comprise a catheter having at least one opening near or at the distal end of the catheter, a barb in fluid communication with the proximal end of the catheter, a drainage tube in fluid communication with the at least one opening, and a vent tube in fluid communication with the barb. A one-way valve may be positioned in line with the vent tube and proximal to the barb, and a controller may be in communication with the one-way valve, the controller being programmed to apply negative pressure to the drainage tube such that the one-way valve opens and fluid passes through the vent tube.

[0027] In another example, a method for draining fluid may generally include positioning a catheter system adjacent to a subject's body, the catheter system having a catheter with at least one opening near or at a distal end of the catheter, a barb in fluid communication with the proximal end of the catheter, and a drainage tube in fluid communication with the at least one opening. A controller in communication with the one-way valve may be operative such that the one-way valve is in line with the vent tube and in fluid communication with the barb, the one-way valve further being located at a point proximal to the barb. Applying negative pressure to the drainage tube may open the one-way valve and allow fluid to pass through the vent tube.

[0028] In another example, a system for assessing a patient's health may generally include a drainage tube configured to be in fluid communication with at least one opening disposed near or at the distal end of a catheter, a pump in fluid communication with the drainage tube and configured to apply negative pressure to the drainage tube, and a valve configured for unidirectional flow and in fluid communication with the drainage tube. A controller may be in communication with the pump, the controller configured to activate the pump to apply negative pressure to remove the airlock from the drainage tube. The controller may be configured to monitor urine output from the patient for a first predetermined period above a urine output threshold and a second predetermined period below the urine output threshold, and the controller may be further configured to determine a risk of acute kidney injury (AKI) when the urine output below the urine output threshold exceeds the second predetermined period.

[0029] In another example, a method for assessing a patient's health may generally include receiving a urine output from the patient through a catheter having at least one opening near or at a distal end of the catheter, applying a negative pressure to a drainage tube in fluid communication with the at least one opening until an airlock is removed from the drainage tube, and monitoring urine output via a controller for a first predetermined time period above a urine output threshold and for a second predetermined time period below the urine output threshold. Further, the method may include determining a risk of AKI when urine output below the urine output threshold exceeds the second predetermined time period.

[0030] A fluid drainage system according to one embodiment may generally include a pump mechanism having a first end fluidly connectable to a portion of the drainage line, and a vent mechanism having a one-way valve and a first end fluidly connectable to the drainage catheter and the drainage line. The pump mechanism may be configured to create a negative pressure in the drainage line when the pump mechanism is in communication with the drainage line, and the one-way valve may be configured to open to the environment when the vent mechanism is connected at the first end and the drainage line is at a pressure lower than ambient pressure to prevent an airlock from occurring in the drainage line.

[0031] One aspect of a method for draining bodily fluid from a subject may generally include providing a pump mechanism connectable to a portion of a drainage line, providing a vent mechanism fluidly connectable to the drainage catheter and the drainage line, and creating a negative pressure in the drainage line via the pump mechanism. The bodily fluid is received in the drainage line through the drainage catheter, and a one-way valve may be fluidly coupled to the drainage line when the drainage line is at a pressure lower than environmental pressure, adjacent the drainage catheter, such that air from the environment is introduced through the one-way valve. Thus, the formation of an air lock in the drainage line may be prevented.

[0032] The drawings illustrate novel features of the invention. A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention are utilized, and the accompanying drawings of which: [Brief explanation of the drawings]

[0033] [Figure 1] FIG. 1 illustrates a sensing Foley catheter according to one embodiment. [Figure 2] FIG. 2 is a diagram showing an example of respiratory rate detection data. [Figure 3] FIG. 3 shows a detailed view of the respiratory system profile. [Figure 4] FIG. 4 is a diagram illustrating an example of sensed data of heart rate and relative cardiac output. [Figure 5] FIG. 5 illustrates data related to relative cardiac output sensing during leg lift exercise in humans. [Figure 6] FIG. 6 is a diagram showing an example of peritoneal membrane detection data. [Figure 7] FIG. 7 is a diagram showing an example of peritoneal membrane detection data. [Figure 8] FIG. 8 is a diagram showing the relationship between intraperitoneal pressure, respiratory blood pressure wave pressure, and cardiac pressure. [Figure 9] FIG. 9 is a flow diagram illustrating one embodiment of the method. [Figure 10A] FIG. 10A illustrates a Foley catheter sensing system according to one embodiment. [Figure 10B] FIG. 10B is a detailed view showing the airlock relief mechanism and fluid collection and analysis system of FIG. 10A. [Figure 10C] FIG. 10C illustrates disposable components of a sensing Foley catheter system according to one embodiment. [Figure 11A] 11A-11C illustrate a Foley catheter sensing system according to various embodiments. [Figure 11B] 11A-11C illustrate a Foley catheter sensing system according to various embodiments. [Figure 11C] 11A-11C illustrate a Foley catheter sensing system according to various embodiments. [Figure 11D] FIG. 11D illustrates a vent tube according to one embodiment. [Figure 11E] FIG. 11E illustrates a catheter system according to one embodiment in which the vent lumen is in direct fluid communication with a fluid collection bag. [Figure 11F] FIG. 11F is a graph showing the valve opening and closing cycle. [Figure 12A] FIG. 12A illustrates another example Foley catheter sensing system. [Figure 12B] FIG. 12B illustrates another exemplary Foley catheter sensing system. [Figure 13] FIG. 13 shows an example of an opening mechanism for a Foley catheter sensing system. [Figure 14] FIG. 14 is a diagram illustrating an example of a elimination mechanism for a Foley catheter system for detection. [Figure 15] FIG. 15 shows a dynamic ventilation system with a vent and pump. [Figure 16] FIG. 16 illustrates a sensing Foley catheter system according to one embodiment with the addition of a vent for pressure relief and sterilization. [Figure 17] FIG. 17 illustrates a sensing Foley catheter system according to one embodiment with a pressure relief vent and relief valve. [Figure 18] FIG. 18 illustrates an embodiment of a collection container, chamber, or cassette that may be included in a Foley catheter system for detecting bacteria, blood, and / or other substances in urine using ultraviolet / photospectroscopy. [Figure 19A] FIG. 19A shows the various wavelengths of absorption of light by E. coli, red blood cells, and plasma in urine. [Figure 19B] FIG. 19B illustrates a display according to one embodiment. [Figure 20] FIG. 20 illustrates a cassette according to one embodiment that includes a septum or flap. [Figure 21] 21 and 22 are graphs illustrating methods for priming a pressure balloon in some embodiments. [Figure 22] 21 and 22 are graphs illustrating methods for priming a pressure balloon in some embodiments. [Figure 23] 23-25 are flow charts illustrating possible logic in various embodiments of the present invention. [Figure 24]23-25 are flow charts illustrating possible logic in various embodiments of the present invention. [Figure 25] 23-25 are flow charts illustrating possible logic in various embodiments of the present invention. [Figure 26] FIG. 26 illustrates a sensing Foley catheter system with loop control in a patient environment according to one embodiment. [Figure 27] FIG. 27 illustrates a sensing Foley catheter system with loop control in a patient environment according to one embodiment. [Figure 28] FIG. 28 illustrates a sensing Foley catheter system with loop control in a patient environment according to one embodiment. [Figure 29] FIG. 29 illustrates a sensing Foley catheter system with loop control in a patient environment according to one embodiment. [Figure 30] FIG. 30 shows in detail a loop control unit with possible input parameters and output operations. [Figure 31A] FIG. 31A is a table listing parameter combinations that allow for possible signatures for identifying acute kidney injury and UTI based on patient parameters. [Figure 31B] FIG. 31B is a table listing parameter combinations that allow possible signatures for distinguishing acute kidney injury, sepsis, and acute respiratory distress syndrome based on patient parameters. [Figure 32] FIG. 32 is a graph showing the pressure signature curve in the collection chamber upon airlock release. [Figure 33] FIG. 33 is a block diagram illustrating a data processing system that may be used in any embodiment of the present invention. [Figure 34] FIG. 34 is a graph showing alternative wavelengths that can be used to distinguish between red blood cells and / or plasma / white blood cells. [Figure 35] FIG. 35 is a graph showing urine volume data immediately after administration of a diuretic. [Figure 36] FIG. 36 illustrates a sensing Foley catheter system with a vent tube according to one embodiment. [Figure 37] FIG. 37 illustrates a sensing Foley catheter system with an internal vent tube according to one embodiment. [Figure 38] FIG. 38 illustrates a sensing Foley catheter system with an internal vent tube according to one embodiment. [Figure 39] FIG. 39 illustrates a sensing Foley catheter system according to one embodiment with an internal vent tube and a positive pressure tube. [Figure 40A] 40A-40C illustrate a Foley catheter sensing system with a bubble reduction mechanism according to one embodiment. [Figure 40B] 40A-40C illustrate a Foley catheter sensing system with a bubble reduction mechanism according to one embodiment. [Figure 40C] 40A-40C illustrate a Foley catheter sensing system with a bubble reduction mechanism according to one embodiment. [Figure 41A] 41A and 41B illustrate a Foley catheter sensing system with a bubble reduction mechanism according to one embodiment. [Figure 41B] 41A and 41B illustrate a sensing Foley catheter system with a bubble reduction mechanism according to one embodiment. [Figure 41C] 41C, 41D, and 41E illustrate a sensing Foley catheter system according to one embodiment with complex flow paths within the collection reservoir. [Figure 41D] 41C, 41D, and 41E illustrate a sensing Foley catheter system according to one embodiment with complex flow paths within the collection reservoir. [Figure 41E]41C, 41D, and 41E illustrate a sensing Foley catheter system according to one embodiment with complex flow paths within the collection reservoir. [Figure 42] FIG. 42 shows a pressure waveform and its disappearance using a pressure balloon. [Figure 43] FIG. 43 is a sample of clinical data illustrating a method for denoising electrocardiogram signals using an electrocardiogram. [Figure 44] FIG. 44 is a sample of clinical data showing cardiac output variability analysis using the model waveform. [Figure 45A] 45A and 45B show cassette-side components of a sealing mechanism for a portion of the lumen between the cassette and the controller / monitor according to one embodiment. [Figure 45B] 45A and 45B show cassette-side components of a sealing mechanism for a portion of the lumen between the cassette and the controller / monitor according to one embodiment. [Figure 46] FIG. 46 illustrates the control side components of the sealing mechanism shown in FIGS. 45A and 45B according to one embodiment. [Figure 47A] 47A and 47B show an embodiment of a lumen connection sealing mechanism between the cassette and the control unit. [Figure 47B] 47A and 47B show an embodiment of a lumen connection sealing mechanism between the cassette and the control unit. [Figure 48] FIG. 48 shows an embodiment of a lumen connection sealing mechanism on the rear of the cassette. [Figure 49] FIG. 49 is a cross-sectional view showing the lumen connection sealing mechanism on the back of the cassette. [Figure 50] FIG. 50 is a dimensional diagram showing cassette-side components of a sealing mechanism according to one embodiment for a portion of the lumen between the cassette and the controller / monitor. [Figure 51]FIG. 51 is a force view showing cassette-side components of a sealing mechanism according to one embodiment for a portion of the lumen between the cassette and the control / monitor. [Figure 52A] 52A and 52B show embodiments of sealing mechanisms in which the base or head or other component includes an orienting element. [Figure 52B] 52A and 52B show embodiments of sealing mechanisms in which the base or head or other component includes an orienting element. [Figure 53] FIG. 53 illustrates an embodiment that includes a venting mechanism that can be added to any urinary drainage system that includes a sampling port. [Figure 54A] 54A and 54B show a barb according to one embodiment that includes a tube seating feature. [Figure 54B] 54A and 54B show a barb according to one embodiment that includes a tube seating feature. [Figure 55A] Figures 55A-55E are examples showing possible methods for predicting risk of kidney damage earlier than the RIFLE criteria. [Figure 55B] Figures 55A-55E are examples showing possible methods for predicting risk of kidney damage earlier than the RIFLE criteria. [Figure 55C] Figures 55A-55E are examples showing possible methods for predicting risk of kidney damage earlier than the RIFLE criteria. [Figure 55D] Figures 55A-55E are examples showing possible methods for predicting risk of kidney damage earlier than the RIFLE criteria. [Figure 55E] Figures 55A-55E are examples showing possible methods for predicting risk of kidney damage earlier than the RIFLE criteria. [Figure 56A] 56A-56C illustrate a Foley system for sensing according to one embodiment, including a peristaltic pump. [Figure 56B] 56A-56C illustrate a Foley system for sensing according to one embodiment, including a peristaltic pump. [Figure 56C] 56A-56C illustrate a Foley system for sensing according to one embodiment, including a peristaltic pump. [Figure 57A] 57A-57C are example screenshots of embodiments disclosed herein. [Figure 57B] 57A-57C are example screenshots of embodiments disclosed herein. [Figure 57C] 57A-57C are example screenshots of embodiments disclosed herein. [Figure 58A] 58A and 58B illustrate a sensory Foley catheter system according to one embodiment, including analysis and recording of various urinary parameters. [Figure 58B] 58A and 58B illustrate a sensory Foley catheter system according to one embodiment, including analysis and recording of various urinary parameters. [Figure 59] FIG. 59 illustrates a sensing Foley catheter system according to one embodiment that includes a pump that acts directly on the urinary drainage lumen or in line with the urinary drainage line. [Figure 60] FIG. 60 illustrates an embodiment that includes a pump mechanism that can be added to any urinary drainage system. [Figure 61] FIG. 61 shows another example that includes a pump mechanism that can be added to any urinary drainage system. [Figure 62] FIG. 62 illustrates an embodiment that includes a fluid flow meter that can be added to any urinary drainage system. [Figure 63] FIG. 63 shows another example that includes a fluid flow meter that can be added to any urinary drainage system. [Figure 64] FIG. 64 illustrates the use of a standard Foley catheter and drainage system with the addition of multiple modular components. [Figure 65ABCD]65A-65D illustrate a Foley catheter system according to one embodiment that includes the ability to measure urine osmolality. [Figure 66A] 66A and 66B show a cassette according to one embodiment that includes electrodes for measuring the conductivity of urine within the cassette. [Figure 66B] 66A and 66B show a cassette according to one embodiment that includes electrodes for measuring the conductivity of urine within the cassette. [Figure 67A] 67A and 67B illustrate a control unit according to one embodiment for use in conjunction with the cassette shown in FIGS. 66A and 66B. [Figure 67B] 67A and 67B illustrate a control unit according to one embodiment for use in conjunction with the cassette shown in FIGS. 66A and 66B. DETAILED DESCRIPTION OF THE INVENTION

[0034] Preferred embodiments of the present invention are described in detail below. However, alternative embodiments of the various elements of the device are possible. Examples of these embodiments are provided below, but the scope of the present invention is not limited to these specific configurations.

[0035] Foley catheter for detection

[0036] 1 is a diagram illustrating a sensing Foley catheter and some of its elements according to one embodiment. The catheter may be understood to have various portions according to the configuration of the catheter when inserted into a human subject, such as a proximal portion that remains external to the subject, a central or urethral portion, and a distal or bladder-retaining portion.

[0037] Various internal lumens traverse the length of the catheter 102, such as, for example, an air or fluid lumen communicating with the bladder retention balloon 104 and retention balloon port 118. The urinary drainage lumen has one or more distal openings 106 present in the bladder portion of the catheter and an opening at 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 integral with the sensing Foley catheter. In some embodiments, the bladder drainage lumen and distal opening may also function as an infusion conduit through which medications or heated or cooled fluids may be infused. One or more analyte sensors (not shown) or one or more temperature sensors (not shown) may be positioned on the catheter, i.e., in either the urethral or bladder-retaining portion of the catheter. Electrical or fiber optic leads may be located within the lumen to allow communication of sensing signals between the distally located sensor and the proximal portion of the catheter, and further to allow communication with a data processing device or controller.

[0038] 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 may be understood to include a pressure interface having a distal face exposed to pressure from within the bladder and a proximal face exposed to the proximal fluid column. The pressure-sensing balloon or membrane is in fluid communication with a fluid column or lumen that is in fluid communication with a pressure port 116 at or near the proximal end of the catheter. Embodiments of the fluid column (filled with either a liquid or gas) may be configured with a dedicated lumen or a shared lumen.

[0039] In some embodiments, a temperature sensor can be located at or near the distal end of the catheter. The temperature port 110 can include a temperature communication line 112 that connects the temperature sensor to a display, connector, and / or controller.

[0040] Note that while Figure 1 shows the proximal end of the catheter as consisting of multiple individual ports, some or all of the ports may be integrated into a single port or integrated into a urinary drainage line that runs to a urinary drainage system and / or control. Other lumens and / or ports may also be present.

[0041] Pressure-based physiological parameters that the sensing Foley catheter system may sense and / or measure via the controller based on the sensed parameters may include, by way of example, peritoneal pressure, respiratory rate, heart rate, relative pulmonary tidal volume, cardiac output, relative cardiac output, and absolute cardiac output. Some Foley catheter embodiments may further comprise a temperature sensor, one or more analyte sensors, electrodes, and / or paired light sources and sensors. Furthermore, such embodiments may also provide other forms of physiological data, such as blood pressure, oxygen saturation, pulse oximetry, electrocardiogram, capillary filling pressure, etc.

[0042] Embodiments of a sensing Foley catheter can sense any one or more of a number of clinically relevant parameters, examples of which include, but are not limited to, urine pH, urine oxygen content, urine nitrate content, respiratory rate, heart rate, bladder or urethral wall perfusion pressure, temperature within the bladder or urethra, electrocardiogram via sensors on the bladder wall or urethra, respiratory volume, respiratory pressure, peritoneal pressure, urine glucose, blood glucose via the urethral and / or bladder mucosa, urine protein, urine hemoglobin, blood pressure, etc. In some embodiments, the catheter can sense multiple parameters, but in other embodiments, it may be limited to a small number, such as a single parameter for a focused application (e.g., respiratory rate in a patient with respiratory distress).

[0043] The disclosed technology can obtain high-resolution time series profiles (pressure as a function of time) of peritoneal pressure in the bladder and process them into discrete pressure profiles that can be assigned to specific physiological sources such as peritoneal pressure, respiratory rate, and heart rate. By tracking the pressure profiles with a sufficiently fast sampling rate, as provided by the present technology, the pressure profiles can be further decomposed and / or analyzed into relative pulmonary tidal volume, cardiac output, relative cardiac output, and absolute cardiac output.

[0044] Thus, aspects of the disclosed technology relate to the fidelity and resolution of a pressure signal generated in response to changes in pressure within the bladder, which reflect the pressure profile within the peritoneal cavity, which pressure profile includes cumulative input from the physiological sources described above. Aspects of the technology further relate to the fidelity and resolution of the conversion of the pressure signal into a high-resolution electrical signal. Aspects of the technology further relate to processing the entire electrical signal profile, which is a proxy for the pressure profile within the peritoneal cavity, into component profiles that can be assigned to physiological sources.

[0045] The sensitivity of an inflated balloon as a pressure sensor is in part a function of the baseline condition, or differential pressure across the balloon membrane. The balloon responds most sensitively to pressure when the baseline differential pressure is near zero. As the baseline differential pressure increases, the sensitivity of the pressure-sensing balloon decreases. Therefore, the disclosed technology provides an automated priming method for maintaining the balloon in an inflated state and at a minimal differential pressure.

[0046] To effectively capture a physiological pressure profile, the profile must be sampled at a rate sufficient to resolve the frequency of changes inherent in the profile. This observation is based on the Nyquist-Shannon sampling theorem, which states that a sampling frequency of at least 2B samples / second is required to resolve an event operating at a frequency of B cycles / second. Applied to physiological pressure cycles, for example, a heart rate of 70 beats / minute requires a sampling rate of at least 140 samples / minute to effectively capture the cycle. This relationship underlies aspects of the disclosed technology that define the sampling rates specifically required to capture physiological pressure cycles, such as relative pulmonary tidal volume, cardiac output, relative cardiac output, and absolute cardiac output.

[0047] Embodiments of the present technology include pressure interfaces, such as may be represented by balloons with either compliant or non-compliant membranes.

[0048] Inflatable pressure-sensing balloons, according to embodiments of the present technology, can assume one or more of at least two basic forms: compliant or non-compliant. In compliant balloon types, likened to traditional party balloons, the pressure-sensing balloon is formed from or includes a compliant membrane. Thus, the membrane's surface area expands or contracts as a function of the balloon's inflation. The membrane's compliance determines various characteristics of the overall balloon depending on the degree of inflation. Upon inflation, the balloon, if unconstrained, maintains a substantially constant or preferred shape, as determined by the mandrel on which the balloon is formed. The balloon's membrane maintains tension as the balloon is inflated from a minimum volume to a maximum volume. Increased inflation pressure, within the range permitted by the compliant membrane, results in a volumetric expansion. Although a balloon as a whole can be considered partially compliant in that its shape accommodates spatial constraints that may be encountered during expansion or inflation, the balloon has a preferred or natural shape, and such shape preference prevents the level of shape conformance or conformity that a non-compliant balloon would exhibit.

[0049] In a non-compliant balloon, the expandable pressure-sensing balloon is formed from or includes a non-compliant or substantially non-compliant membrane. As a result, the membrane's surface area does not expand or contract in response to the degree of inflation or pressurization of the balloon. A non-compliant pressure-sensing balloon can generally be compared to a traditional Mylar® balloon. The lack of compliance of the membrane determines various characteristics of the entire balloon in response to the degree of inflation. As the balloon expands from its minimum volume to near its maximum volume, the balloon membrane becomes compliant and relaxed. Inflation of a non-compliant balloon occurs due to the wrinkles and folds in the membrane being outwardly oriented. Contraction or compression of a non-compliant balloon occurs due to the wrinkles and folds being generally inwardly oriented. When a non-compliant balloon is fully inflated (or substantially inflated) without being placed in a confined space, it assumes a preferred or natural shape determined by the shape of the balloon membrane or fabric. However, in the partially inflated state, the entire balloon is very compliant and deformable, allowing it to assume any desired shape within the enclosed space.

[0050] Inflatable pressure-sensing balloons according to embodiments of the present technology may also incorporate features of both the two basic configurations: compliant and non-compliant. In these embodiments, the membrane may include compliant and non-compliant regions. This hybrid balloon generally operates in a manner that incorporates the behavioral aspects of both compliant and non-compliant balloons, as described above. Furthermore, compliant balloons may be formed with membranes of varying composition or thickness. In such embodiments, regions of different thickness or composition may have different degrees of compliance, which may affect the behavior of these regions during balloon inflation. In yet another embodiment, the membrane's compliance may have a bias or polarity that tends to allow compliance in one or more directions but not in one or more other directions.

[0051] An embodiment of the Foley catheter for sensing involves a device that utilizes a very small pressure lumen for air transmission. Pressure measurements have been performed with inner lumen diameters of 3 mm, 1 mm, and 0.5 mm. There was little signal degradation as the air lumen diameter was reduced from 3 mm to 1 mm and 0.5 mm.

[0052] These data demonstrate the suitability of the pressure transmission system of this embodiment for pediatric catheters as small as 4F in diameter. In this embodiment, the catheter tip has a lower profile than the rest of the catheter, allowing for a consistently small diameter even with the addition of a pressure-sensing balloon. Therefore, the catheter of the present invention is uniquely suited for pediatric applications, where better, less invasive monitoring methods are desperately needed. Alternatively, to minimize the number of lumens required, the retention balloon itself can be used as a pressure balloon. In one embodiment, the retention balloon is fully inflated and used only to track macro trends in IAP. In another embodiment, the retention balloon is only slightly inflated to increase the balloon's sensitivity to small changes in pressure. This embodiment allows for more precise measurement of minute parameters, such as heart rate, relative stroke volume, relative cardiac output, respiratory rate, and relative tidal volume. Additionally, the smaller pressure lumen allows for more space to accommodate other technologies, such as sensors, within larger catheters.

[0053] In embodiments of a sensing Foley catheter in which a retention balloon is used as a pressure balloon, the pressure measured within the retention balloon is offset by the pressure required solely to inflate the balloon sufficiently to function as a retention balloon. As a result, the inflation pressure, and possibly the pressure resulting from the retention balloon's contact with the inner surface of the bladder, must be subtracted from the pressure measurement. In this manner, smaller pressure changes can be tracked as if they were measured with a separate pressure balloon. The inflation pressure offset is determined by measuring the pressure within the retention balloon when it is initially inserted into the patient, by measuring the inflation pressure of the retention balloon outside the patient, or by other means. The retention balloon can be filled with a fluid, air, or other suitable gas.

[0054] Embodiments of the disclosed technology may include embodiments in which the pressure sensor is a mechanical pressure sensor, such as one that uses fiber optic, strain gauge, magnetic, resonant, and / or other suitable technology.

[0055] 2 shows an example of respiratory rate detection data from a human subject provided by a Foley catheter detection system according to one embodiment. During this test, the subject performs the following respiratory sequence: (1) breath-hold at end-expiration, (2) Valsalva, (3) hyperventilation, (4) Valsalva, (5) breath-hold at end-expiration.

[0056] Figure 3 shows a detailed portion of a normal breathing period in a breathing profile similar to that shown in Figure 2. Note that the pressure curve clearly shows the respiratory peaks, allowing the respiratory rate to be determined, and the heart rate peaks, allowing the heart rate to be determined.

[0057] 4 illustrates an example of heart rate and relative cardiac output sensing data from a human subject, as well as a simultaneously and independently measured electrocardiogram tracing, provided by a Foley sensing catheter system according to one embodiment, clearly showing that the peaks in heart rate measured by the Foley sensing catheter are consistent with the heart rate.

[0058] FIG. 5 shows data related to sensing relative cardiac output during human leg-raising exercise, where cardiac output increases due to an increased cardiac pulse amplitude.

[0059] The data shown in Figures 6 and 7 were obtained from a study conducted using Yorkshire pigs under an IACUC-approved protocol. Figure 6 shows an example of peritoneal sensing data, primarily respiratory rate, from a pig provided by a Foley catheter sensing system according to one embodiment. Figure 7 illustrates an example of a pig study demonstrating the ability of a Foley catheter sensing system according to one embodiment to detect intraperitoneal hypertension. In this study, the peritoneal cavity was accessed using a 5 mm Tenamian trocar. A 5 L bag of lactated Ringer's solution was attached to the trocar with a peristaltic pump and infused at a rate of approximately 1 L per minute. Once a pressure of approximately 20 mmHg (approximately 2.67 kPa) was achieved, fluid flow was stopped, resulting in zero net fluid inflow and outflow into the cavity.

[0060] FIG. 8 shows a schematic arrangement of intra-abdominal pressure, respiratory wave pressure, and cardiac pressure as a two-dimensional plot of pressure (in mmHg on a logarithmic scale) versus frequency (Hz). It can be seen that there is an inverse correlation between pressure and frequency, and this arrangement allows the various physiological pressure-related parameters to occupy distinct sectors. It is the distinctness of both these pressure and / or frequency profiles that allows embodiments of the methods disclosed herein to decompose an overall time series of pressure profile into distinct sub-profiles according to their physiological origin. Intra-abdominal pressure measurements can be resolved in a frequency range of about 0 Hz to about 0.5 Hz. Respiratory pressure measurements can be resolved in a frequency range of about 0.25 Hz to about 0.75 Hz. Cardiac pressure measurements can be resolved in a frequency range of about 0.75 Hz to about 3.0 Hz. Intra-abdominal pressure measurements can be resolved in an amplitude range of about 5 mmHg to about 30 mmHg (about 0.67 kPa to about 4 kPa). Respiratory pressure measurements can be resolved in an amplitude range of about 0.5 mmHg to about 5 mmHg (about 0.067 kPa to about 0.67 kPa). Cardiac pressure measurements can be resolved in an amplitude range of about 0 mmHg to about 0.5 mmHg (about 0 Pa to about 0.067 kPa). The sampling frequency (the frequency at which pressure measurements are taken) is preferably about twice the resolution frequency. For example, the sampling frequency can be about 0 Hz to 1 Hz for intraperitoneal pressure measurements, about 0.5 Hz to 1.5 Hz for respiratory pressure measurements, and about 1.5 Hz to 6 Hz for cardiac pressure measurements.

[0061] 9 is a flow diagram illustrating a method, according to one embodiment, for monitoring pressure that dynamically evolves within the abdominal cavity as waves of varying frequency and amplitude, sensed from within the bladder. A high-fidelity pressure profile is generated by a pressure interface and transmitted proximally through a fluid column. More specifically, a pressure transducer converts the high-fidelity pressure waves into high-fidelity electrical signals that capture the pressure frequency and amplitude. The generated high-fidelity electrical signals are then processed by a controller to generate data subsets that reflect components within the overall pressure profile, which are attributable to specific physiological sources, such as peritoneal pressure, respiratory rate, heart rate, relative cardiac output, and patient movement or activity.

[0062] Foley Catheter System for Detection

[0063] 10A illustrates an embodiment of a sensing Foley catheter used in combination with an airlock elimination mechanism and a bodily fluid collection and analysis system, according to one embodiment. Both urinary drainage and pressure measurement benefit from eliminating or reducing airlock in the urinary drainage line.

[0064] The sensing Foley catheter 1000 is similar to the sensing Foley catheter shown in FIG. 1. The sensing Foley catheter is shown in use in a bladder 1014. Note that some of the ports at the proximal end of the catheter shown in FIG. 1 are combined in the embodiment shown in FIG. 10A. A urinary drainage tube 1001 is also shown here. The urinary drainage tube may be combined with the sensing Foley catheter or may be a separate piece. The urinary drainage tube 1001 and / or the sensing Foley catheter may include a vent barb (or barbs) 1016, or the vent barb may be a separate component. An airlock elimination 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 elimination mechanism and fluid collection and analysis system includes a base / control unit 1018, a fluid collection bag 1020, and a reservoir or cassette 1022. The combination of the sensing Foley catheter 1000, the urinary drainage tubing 1001, the airlock elimination mechanism, and the fluid collection and analysis system 1002 is also referred to herein as a sensing Foley catheter system. The sensing Foley catheter, urinary drainage line, and reservoir / cassette are disposable and may be sold as a unit. This disposable assembly is shown in Figure 10D, and includes the sensing Foley catheter 1000, the urinary drainage tubing 1001 (including the vent barb), and the reservoir / cassette 1022.

[0065] The vent barb 1016, like the urine sampling port 1004, can include one or more vents 1006. In this embodiment, the vents 1006 are preferably made of a membrane that allows gas to pass through but not liquids, such as a hydrophobic membrane. An example of such an exemplary vent is a PTFE (polytetrafluoroethylene), ePTFE (expanded PTFE), or Versapor® (available from Pall Corporation, Port Washington, New York) membrane, although other materials may be used. The vents allow air to enter the system when negative pressure is applied to the drainage tube, and allow air to escape from the system when an airlock occurs in the drainage line, creating a positive pressure. This mechanism can prevent aspiration trauma, for example, to the bladder wall. The vents 1006 may incorporate one-way valves that prevent air from entering or leaving the drainage line. In a preferred embodiment, a one-way valve is used to prevent air from exiting the drainage line, but allows air to enter the drainage line via vent 1006. In this way, the valve also prevents urine from contacting vent 1006.

[0066] The urinary drainage tube 1001 may include multiple lumens, including a pressure lumen 1010, a temperature lumen 1008, and a urine lumen 1012. The pressure lumen 1010 is in fluid communication with the pressure sensing balloon 108, as well as a pressure transducer interface 1026 of the controller 1018. The temperature lumen 1008 communicates with a temperature sensor (not shown) in the sensing Foley catheter and also with a temperature connector port 1024 in the controller. The urine lumen 1012 is in fluid communication with one or more openings 106 and a urine reservoir or cassette 1022.

[0067] The disposable measurement reservoir, collection reservoir, chamber, or cassette element 1022 is configured to fit into the cassette mount, base, or controller 1018 and interface with the controller element. The controller pump interface (back of the cassette pump interface 1148) connects to the pump 1134 and the cassette pump interface 1148 on the disposable cassette element. The pump is configured to create a vacuum inside the cassette element, which is then transferred to the urine drainage lumen of the drainage line. Preferably, the collection reservoir / cassette is rigid to maintain a constant volume when the pump applies negative pressure. The applied negative pressure can be monitored with a pressure sensor. When the airlock is cleared, a sinusoidal pressure curve, as shown in Figure 32, is created. As suction is applied, the pressure decreases, eventually reaching an inflection point as the urine meniscus passes its lowest point within the drainage tube. At this point, only a small amount of suction is required to continue clearing the airlock; therefore, once the airlock is fully cleared, the pump power can be reduced to minimize the amount of suction transferred to the bladder. For example, in a large container without this pressure sensing capability, a significant negative pressure may be exerted on the bladder once the airlock is cleared and before the container equilibrates to the atmosphere. The controller pressure interface (at the rear of the cassette pressure interface 1150) connects to a pressure measurement device, such as a pressure transducer, and the cassette pressure interface 1150. The pressure measurement device is configured to measure the volume of urine or other fluids based on the pressure exerted on the pressure measurement device, which may be a pressure transducer. The ultrasound transducer interface 1130 also measures urine volume. Ultrasound measurement can be used in conjunction with pressure measurement, or either can be used to measure the volume of urine or other fluids. An active pinch valve 1132 is configured to connect to the cassette outflow tubing. The pinch valve controls the emptying of the cassette container and is controlled by the controller to release urine / fluid when a predetermined volume of urine in the cassette is reached, as measured by pressure and / or ultrasound measurement.The amount of urine in the cassette is measured, and when a predetermined amount of urine is reached, it is discharged into the urinary drainage bag 1020 via the pinch valve, thereby emptying the cassette. For example, the cassette can be emptied when the amount of urine in the cassette reaches approximately 50 ml. Alternatively, the cassette can be emptied when the amount of urine in the cassette reaches approximately 40 ml. Alternatively, the cassette can be emptied when the amount of urine in the cassette reaches approximately 30 ml. Alternatively, the cassette can be emptied when the amount of urine in the cassette reaches approximately 20 ml. Alternatively, the cassette can be emptied when the amount of urine in the cassette reaches approximately 10 ml. This allows for accurate measurement of urine volume over time.

[0068] In some embodiments, a capacitive micromachined ultrasonic transducer (CMUT) may be used to measure the urine volume within the cassette. This provides a cheaper ultrasonic transducer that can cover the entire bottom surface of the cassette and / or one or more sides of the cassette, making tilting of the cassette less of an issue.

[0069] Emptying of the cassette may be enhanced or accelerated by pressurizing the cassette as it empties.

[0070] Alternatively, the controller may use a set time period during which the cassette is emptied and measure the volume of urine in the cassette immediately prior to emptying. Alternatively, the controller may empty the cassette upon an event, such as an airlock release due to pump activation. For example, the controller may set a periodic airlock release cycle, after which the controller measures the volume of urine in the cassette, and subsequently empties the cassette.

[0071] For example, the controller may control the pinch valve to empty the reservoir / cassette when the urine volume reaches approximately 50 ml. Alternatively, the controller may control the pinch valve to empty the reservoir / cassette hourly after measuring the urine volume in the cassette. Alternatively, the controller may control the pinch valve to empty the reservoir / cassette during or after a urine output event, such as activation of a pump. Alternatively, these triggers may be combined so that the controller controls the pinch valve to empty the reservoir / cassette.

[0072] Other technologies can be used in addition to or instead of pressure and / or ultrasound to measure urine volume, such as pressure-based, resistance-based, capacitance-based, ultrasound-based, weight-based, or optical-based technologies. To increase the accuracy of the volume measurement, two or more technologies can be used so that the measurements can be compared to each other. Two or more volume measurements made by one or more technologies can be used for redundancy, backup, or in combination with each other to obtain more accurate urine volume measurements.

[0073] For example, a camera can be used to measure the fluid level in the reservoir by identifying the fluid / air interface. The known dimensions of the reservoir can then be used by the controller to calculate the fluid volume. The camera can also be used to measure the tilt of the system by identifying the fluid / air interface and the end of the reservoir. The controller can calculate the angle between them to determine the tilt of the system. If this angle changes rapidly over time, the controller can determine that the system is moving, such as when a patient moves between rooms. The controller can issue alerts when certain conditions are detected by the camera / controller. Examples include high tilt alerts, motion alerts, and detection alerts (for conditions such as blood or bubbles in the urine). In situations where the urine reservoir / system is placed on a horizontal surface, the tilt can approach 90 degrees. In such situations, the controller may determine that the reservoir is placed on its side and may not be functionally emptying, or that there is an increased risk of urine backflow into the drainage tube. The controller can automatically disable certain system functions, such as drain line cleaning and reservoir emptying. The controller can automatically set the system to "Dam Foley mode," in which the urine drainage path bypasses the cassette and drains directly into the bag. Additionally or alternatively, the controller can shut off certain valves, such as the valve between the reservoir and the drainage tube.

[0074] The bed hook 1116 allows the control unit to be hooked onto a bed or other surface as needed. It is also possible to connect the control unit to portable equipment for patient transport. The collection bag hook / hole 1102 is for attaching a drainage bag into which urine / fluids are ultimately collected after passing through the pinch valve. The collection bag hook 1102 may be configured to perform strain measurements to measure the weight of the fluid in the bag, thereby providing another method for measuring the volume of the fluid in the bag. For example, a piezoelectric transducer could be used. Specific gravity measurements may also be used by the control unit to determine useful volume measurements based on weight and specific gravity.

[0075] The screen 1110 is for displaying information including current urine / fluid volume status, system status, etc. The screen 1110 may be touch-sensitive and can receive inputs including settings, screen display changes, menu changes, etc. The 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 below the cassette 1022 or elsewhere in the control unit / base. The temperature input port 1024 connects to the sensing Foley catheter via lumen 1008 or a thermistor / temperature sensor for measuring body temperature by other means. The temperature output port 1122 is for transmitting any temperature measurements to an external device and / or monitor. The adapter port 1124 is for adapting the control unit to other equipment, such as an RFID adapter. This can be used to enable any additional / advanced functionality, 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 only when that information is needed, at the hospital's expense. Activation of advanced features can also be controlled, for example, by using different disposable components. Alternatively, advanced features can be enabled as part of the disposable or via a software upgrade purchased separately. Software upgrades can be delivered wirelessly, via a USB dongle, a microSD card, an EPROM card, or other suitable technology. Individual patient and / or patient group data can also be stored by the control unit. Patient data can be stored in memory, a USB, a microSD card, an EPROM card, a hard disk, or the like. Patient data can be transferred wirelessly or via a wired connection to other storage devices, such as a server on the Internet or an intranet. Patient data can be anonymized.Patient data, such as a patient ID, may be stored in the RFID adapter, allowing data unique to a particular patient to be recognized by the controller and associated with the disposables used by that patient. The RFID adapter may be located on the disposable portion of the system, for example, on cassette 1022, or anywhere else where disposable components interface with non-disposable components. Additionally, because all collected patient data is stored in the RFID adapter, it is possible to use different monitors on the same patient without replacing the disposable portion of the system.

[0076] A power LED / indicator 1114 indicates whether the power is on or off. An error LED / indicator 1112 is displayed if any error occurs within the system. Details of the error can be displayed on the screen 1110, but the indicator 1112 alerts the user that an error exists. The indicator may also include an audible or other warning.

[0077] Port 1108 is for connecting to other devices for downloading, uploading, software upgrades, integration with EMR (Electronic Medical Record) systems, etc. Port 1108 may be a USB port or other suitable port. SD® port 1106 is for data downloads. Power port 1104 is for connecting the controller to a power source, such as a wall outlet, to provide power to the controller.

[0078] The urine / fluid drainage bag 1020 includes one-way valves 1136 connected to the overflow tube 1138 and the outflow tube 1140 to prevent urine / fluid from leaving the drainage bag once collected. These valves may be passive or controlled by the controller. These valves also prevent air from entering the collection container 1022 when the pump 1134 is pulling a vacuum, thereby ensuring that the vacuum acts on the drainage tube and not the bag. In a preferred embodiment, one valve is used for both the overflow tube and the outflow tube. Attachment hooks / holes 1102 allow the drainage bag 1020 to be removably attached to the controller 1018. A vent 1142, which may be a hydrophobic or other vent, allows air or gas to exit the drainage bag but not fluid. This prevents excess air and potentially pressure from building up within the bag, allowing for efficient filling of the drainage bag. Graduated markings 1144 provide a somewhat coarse measurement of the collected fluid volume in the bag. An outflow valve 1146 may be used to empty the fluid / urine bag. Preferably, the valve is easily operable by one person. The collection bag hook 1102, when configured as a strain measurement element, can also force an alarm when the bag is full and needs to be emptied. The alarm can also sound if the bag is subjected to excessive force, such as when the bag is pulled during patient transfer or gets caught on an obstacle. Weight or mass can also be used to determine if the bag is full, for example, using a scale. Alternatively, or in addition, pressure measurements within the reservoir / cassette can be used to determine when the bag is full.

[0079] An overflow barrier 1137 is shown on the collection container / reservoir / cassette 1022. The overflow barrier is generally located above the water level at which the controller empties the cassette. For example, if the controller empties the cassette when 50 ml of fluid is present, the overflow barrier will reach a height above the water level of the 50 ml fluid volume. For example, the overflow barrier may be approximately 5-10 mm above the water level of the emptying volume. Alternatively, the overflow barrier may be approximately 10-20 mm above the water level of the emptying volume. Alternatively, the overflow barrier may be approximately 20-30 mm above the water level of the emptying volume. Alternatively, the overflow barrier may be approximately 30-40 mm above the water level of the emptying volume. Alternatively, the overflow barrier may be approximately 40-50 mm above the water level of the emptying volume. Alternatively, the overflow barrier may be approximately 50-100 mm above the water level of the emptying volume. The path between the urine collection area 1135 and the overflow area 1139 may be direct, as shown here, or it may be more tortuous or complex, as shown in Figures 41B-41E.

[0080] The patient's temperature is measured using a thermistor / temperature sensor located within the patient's body. This temperature may be displayed on a third-party device via a control unit. Figure 10B shows how a parallel potentiometer can be used to reduce error in the temperature measurement before transmission to an external display or device.

[0081] The drainage bag can be made of a suitable material, such as clear vinyl. The one-way valve can be made of a suitable material, such as vinyl. The hydrophobic vent can be made of ePTFE, Versapor®, or other suitable material. The outflow valve can be made of a suitable material, such as PVR, PC, etc.

[0082] Pressure measurements from the sensing Foley catheter may be used to activate a pump to empty the drainage tube, for example, if the pressure sensed in the bladder exceeds a preset value, the pump can be activated to pump urine more quickly into the drainage tube.

[0083] The control / base and / or reservoir / cassette may include an accelerometer or other sensor to determine when the control / cassette is level and when it is not. An alarm may sound if the control / cassette is not level. Alternatively, urine volume measurements may be adjusted to account for different angles within the system.

[0084] The bottom of the urine reservoir within the cassette may be rounded and configured to completely empty urine from the cassette when the pinch valve is opened.

[0085] In some embodiments, the control / monitor may be integrated into the bed itself.

[0086] FIG. 10C is a detailed diagram showing the airlock release mechanism and fluid collection and analysis system 1002. Screen 1110 displays a user interface, including patient parameters and touchscreen or other controls. Heart rate area 1152 indicates the patient's heart rate, as determined by the controller based on cystometric pressure measurements sensed by the sensing Foley catheter. Respiratory rate area 1154 indicates the patient's respiratory rate, as determined by the controller based on cystometric pressure measurements sensed by the sensing Foley catheter. Core temperature area 1156 indicates the patient's core temperature, as determined by a temperature sensor in the sensing Foley catheter or the like. Urine volume area 1158 indicates the patient's current and / or average urine volume, as determined by the controller based on urine volume measurements measured by a pressure measurement device connected to pressure interface 1150 and / or ultrasound transducer interface 1130. Sepsis index area 1160 indicates the patient's likelihood of sepsis, as determined by the controller based on one or more collected and / or calculated patient parameters. For example, factors such as abnormal body temperature, abnormal heart rate, abnormal respiratory rate, and / or urine output can be considered in determining the risk of sepsis. Changes in these parameters can also be used to assess risk. For example, a decrease in urine output, an increase in heart rate, an increase or decrease in core body temperature, etc. can be indicators of sepsis.

[0087] Other risk assessments can be determined by the controller and displayed in addition to or instead of the sepsis index. These include risk assessments for acute kidney injury, urinary tract infection, elevated intra-abdominal pressure, abdominal compartment syndrome, infection risk, sepsis, and ARDS (acute respiratory distress syndrome). For example, Figure 31A shows example risk algorithms for acute kidney injury and urinary tract infection. Figure 31B shows example risk algorithms for acute kidney injury, sepsis, and acute respiratory distress syndrome. Measured urine parameters may include conductance, specific gravity, urine volume, presence or absence of infection, bacteria, white blood cells, oxygen concentration, etc.

[0088] Graphical indicators 1162 show historical data for any of these areas. For example, a user may touch the screen to toggle the graphical display to show a history of the patient's urine output, temperature, heart rate, respiratory rate, sepsis index, risk of acute kidney injury, urinary tract infection, elevated intra-abdominal pressure, abdominal compartment syndrome, infection risk, or other suitable parameters. The historical time period can be any time period configured by the user, such as all time, daily, hourly, etc. Risk factors that are out of range, i.e., at elevated risk, may be automatically displayed here or elsewhere on the display. Alerts and / or ranges can be user-configurable and can include absolute values and trends over time. For example, a visual and / or audio alert can be triggered if core body temperature rises by more than 2 degrees during a particular time period.

[0089] FIG. 11A illustrates an embodiment of a Foley catheter sensing system (including an airlock relief mechanism, fluid drainage, collection and analysis system / control) similar to that shown in FIG. 10A in which a vent 1180 is located on the control unit 1018 or reservoir / cassette 1022 instead of a vent barb (or barbs) 1182. In this embodiment, the vent 1180 is in fluid communication with the urinary drainage lumen 1012 via a vent lumen 1184, which fluidly connects to the urinary lumen 1012 at the barb 1182. In this embodiment, the barb design is simplified compared to the embodiment shown in FIG. 10A; the drainage tube simply has an additional lumen. The vent may be located anywhere in the system, and the fluid interface with the urinary lumen may also be located anywhere in the system.

[0090] FIG. 11B illustrates an embodiment of a sensing Foley catheter system similar to that shown in FIG. 11A. In this embodiment, a gas-permeable vent / filter is incorporated into the cassette 1022 and / or control unit 1018. A vent lumen can pass from a barb 1182, along the drainage tubing 1012, and into a vent tube 1184. The vent lumen may terminate externally of the cassette and / or control unit, or, as shown here, may pass through the cassette and possibly the control unit and incorporate a gas-permeable vent / filter 1180. Also shown in FIG. 11B is a valve 1186. The valve may be a one-way valve, allowing the flow of fluid (e.g., atmospheric air) through the vent lumen, through the barb, into the drainage tubing, or elsewhere along the drainage tubing or Foley catheter, or into the base / control unit 1018. This valve may prevent fluids, such as urine and / or air, from passing through the vent tube and potentially reaching the filter. The valve may be passive, as shown here, or may be actively controlled by the controller. The valve may be located anywhere within or along the vent lumen, such as within the barb, along the vent tubing, within the cassette, within the controller, or outside the controller, e.g., on the non-patient side of the controller.

[0091] In some embodiments, the valve is actively controlled via the controller by controlling the negative pressure in the drainage tube. The valve may open by the controller applying a negative pressure in the drainage lumen of the drainage tube, and close by the controller reducing the vacuum applied to the drainage tube (i.e., applying little negative pressure, zero pressure, or a slight positive pressure to the drainage tube). Because the catheter's drainage lumen and the drainage tube are in fluid communication with the lumen of the vent tube, negative pressure applied to the drainage tube is also applied to the lumen of the vent tube, causing the valve to open when the pressure differential across the valve exceeds the valve's cracking pressure. The valve can be closed again by reducing the vacuum applied to the drainage lumen, thereby reducing the pressure differential across the valve 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 vent tube, even though the valve itself is a passive valve.

[0092] In some embodiments, the controller may actively open the valve periodically, for example, on a regular schedule. This is shown graphically in FIG. 11F. For example, the controller may open the valve (represented by T1) at least every 30 minutes, hold the valve open for at least 15 seconds (represented by T2), and then close the valve for another 30 minutes before the cycle begins again. The difference between the vacuum applied to open the valve and the vacuum applied to keep the valve closed is represented by DIFF in the diagram. DIFF is greater than the valve's crack differential pressure. Alternatively, T1 may be at least 60 minutes. Alternatively, T1 may be at least 20 minutes. Alternatively, T1 may be at least 10 minutes. Alternatively, T1 may be at least 5 minutes. Alternatively, T2 may be at least 5 seconds. Alternatively, T2 may be at least 10 seconds. Alternatively, T2 may be at least 20 seconds. Alternatively, T2 may be at least 30 seconds.

[0093] Although FIG. 11F shows a case where the valve closing pressure is negative, the valve closing pressure may be zero or may be positive.

[0094] The length of the cycle may alternatively be variable, with T1 and / or T2 depending on the urine output flow rate. The cycle may alternatively be based on a system that detects airlocks 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 at the barb.

[0095] In some embodiments, the valve 1186 can be in place without a filter. In some embodiments, a filter may be between the drainage lumen and the valve 1186.

[0096] In some embodiments, the vent tube 1184 is integral with the drainage tube 1012 along all or part of the length of the drainage tube.

[0097] The valve may be a valve suitable for medical applications, such as a duckbill valve, umbrella valve, ball valve, dome valve, Belleville valve, cross-slit valve, or X-fragment valve. The crack pressure of the valve may be very low or high, but is generally between zero and the magnitude of the negative pressure drawn by a vacuum pump. In some embodiments, the crack pressure is essentially zero.

[0098] FIG. 11C illustrates an embodiment of a sensing Foley catheter system similar to that shown in FIG. 11B. In this embodiment, the vent tube includes a portion of the lumen with a smaller diameter between the barb and the valve. By reducing the inner diameter of the tube between the barb and the valve, a column of air can be formed between the valve and the barb, which generally prevents urine from entering the vent tube when the vent tube valve is closed. When the vent tube valve is open, fluid flow generally is in the opposite direction (i.e., into the drainage lumen), thereby also preventing urine from entering the vent tube.

[0099] FIG. 11D illustrates an example of a vent tube with a reduced diameter section. The first section 1188 is closest to the patient and has an inner diameter ID1 and a length L1. In this embodiment, the valve 1186 generally allows fluid flow only from right to left, as indicated by the dashed arrow. The second section 1190 is further from the patient and has an inner diameter ID2 and a length L2. In some embodiments, L1 is smaller than L2, and ID1 is smaller than ID2. In some embodiments, ID1 is smaller than ID2, but the lengths may be different or the same. L1 + L2 may be approximately the same length as the drainage tube.

[0100] In some embodiments, ID1 may be about 1.8-2.0 mm. In some embodiments, ID1 may be about 1.6-1.8 mm. In some embodiments, ID1 may be about 1.4-1.6 mm. In some embodiments, ID1 may be about 1.2-1.4 mm. In some embodiments, ID1 may be about 1.0-1.2 mm. In some embodiments, ID1 may be about 0.8-1.0 mm. In some embodiments, ID1 may be about 0.5-0.8 mm. In some embodiments, ID1 may be about 0.2-5 mm. In some embodiments, ID1 may be less than about 1 mm. In some embodiments, ID1 may be less than about 2 mm. In some embodiments, ID1 may be less than about 3 mm. In some embodiments, ID1 may be less than about 4 mm. In some embodiments, ID1 may be less than about 2 mm. Preferably, ID1 is small enough to hold a siphon for all or part of its length.

[0101] In some embodiments, ID2 can be about 1.8 to 2.0 mm. In some embodiments, ID2 can be about 1.6 to 1.8 mm. In some embodiments, ID2 can be about 1.4 to 1.6 mm. In some embodiments, ID2 can be about 1.2 to 1.4 mm. In some embodiments, ID2 can be about 1.0 to 1.2 mm. In some embodiments, ID2 can be about 0.8 to 1.0 mm. In some embodiments, ID2 can be about 0.5 to 0.8 mm. In some embodiments, ID2 can be about 0.2 to 5 mm. In some embodiments, ID2 can be less than about 4 mm. In some embodiments, ID2 can be less than about 5 mm. In some embodiments, ID2 can be less than about 6 mm. In some embodiments, ID2 can be greater than about 2 mm. In some embodiments, ID2 can be greater than about 3 mm. In some embodiments, ID2 can be greater than about 4 mm. In some embodiments, ID2 may be greater than about 5 mm. In some embodiments, ID2 may be greater than about 6 mm.

[0102] In some embodiments, L1 may be less than about 5 cm. In some embodiments, L1 may be less than about 10 cm. In some embodiments, L1 may be about 5-10 cm. In some embodiments, L1 may be about 10-20 cm. In some embodiments, L1 may be about 20-30 cm. In some embodiments, L1 may be about 30-50 cm. In some embodiments, L1 may be greater than about 50 cm. In some embodiments, L1 may be greater than about 1 cm. In some embodiments, L1 may be greater than about 2 cm. In some embodiments, L1 may be greater than about 5 cm. In some embodiments, L1 may be greater than about 10 cm.

[0103] In some embodiments, L2 may be between about 50 and 150 cm.

[0104] In some embodiments, ID1 and ID2 may be the same.

[0105] FIG. 11E illustrates a catheter system according to one embodiment in which the vent lumen 1184 is in direct fluid communication with the fluid collection bag 1020. This embodiment may or may not include a control unit, including sensing capabilities. In this embodiment, an airlock is avoided by the vent lumen venting the urinary drainage lumen 1012 using a vent 1142 on the fluid collection bag. A vent may additionally or alternatively be provided anywhere along the vent lumen. The vent lumen may extend the entire 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. The fluid collection bag 1020 in this, and potentially other, embodiments may include a rigid or semi-rigid portion 1196 to ensure that the fluid collection bag does not collapse around the connection point 1194. This embodiment may or may not include a valve 1186. The vent tube 1184 may be integrated into the drainage tubing system or may be an add-on component, connecting at or near the barb on the Foley catheter to a connection point 1194 on the drainage bag.

[0106] FIG. 12A illustrates an embodiment of a sensing Foley catheter system similar to the system illustrated in FIG. 10A , but in contrast to the system illustrated in FIG. 10A , no pressure balloon is utilized. Instead, intrabladder pressure is measured via the urinary lumen (or other lumen) of the sensing Foley catheter. In this embodiment, the pressure lumen 1202 is connected to a vent 1204 or other location in the system outside the patient's body and is in at least periodic fluid communication with the catheter's drainage / urinary lumen. In this embodiment, the sensing Foley catheter system can be used with any standard Foley catheter. Note that any embodiment of the sensing Foley catheter system can be used with a standard Foley catheter. The system illustrated in FIG. 12A can also be used with a standard Foley catheter without the pressure lumen 1202 when intrabladder pressure measurement is not desired.

[0107] Some embodiments of the Foley sensing system can measure intraperitoneal pressure using a standard, commercially available Foley catheter. This allows IAP measurements to be incorporated into the analysis even when using a standard Foley catheter. In some embodiments, the controller can cause the pump to introduce air or gas bubbles into the drainage line of the Foley catheter. By measuring the pressure in the drainage line with a pressure sensor, the controller can determine when the gas / air bubbles exit the Foley catheter and enter the bladder. The pressure required to push the bubble-laden fluid column into the drainage line increases until the bubbles exit the drainage line. The pressure at which the bubbles exit the Foley catheter is equal to the intraperitoneal pressure. The fluid column can be solid or intermittent. The IAP measurement sequence can be performed periodically by the controller. This can be performed before or after clearing the airlock. IAP measurements can also be performed manually by physically monitoring the pressure with a gauge, such as a sphygmomanometer. The vent tube can be closed before performing this type of IAP measurement. The gas may be sterile and / or may be sterilized during transport by ultraviolet light, for example at the barb.

[0108] In some embodiments of the sensing Foley system, the irrigation lumen may be included in the Foley catheter, or a separate irrigation catheter with an irrigation lumen may be used to irrigate the bladder. In these embodiments, the controller of the sensing Foley system may communicate with the irrigation pump so that the volume of irrigation fluid can be subtracted from the measured fluid volume to accurately measure urine volume (not including irrigation fluid).

[0109] In embodiments in which a standard Foley catheter is used with a sensing Foley system, a specialized clamp may be used to clamp one or more lumens of the drainage tube without clamping the urinary drainage lumen of the drainage tube. The clamp may be configured, for example, to fit a clamping mechanism onto the drainage tube such that the pressure lumen of the drainage tube is closed but the urinary drainage lumen is not closed.

[0110] 12B illustrates an embodiment of a Foley catheter sensing system that does not include IAP or temperature measurement, but still includes airlock prevention.

[0111] Figures 10A, 10C, 11, and 12 illustrate embodiments of a sensing Foley catheter system that include a vent near the patient end of the drainage tube that allows air to enter the drainage tube if negative pressure is created by a siphon in the drainage tube, a pump mechanism, or both. Without a vent / filter, such negative pressure could cause aspiration trauma, including trauma to the bladder mucosa. Note that these embodiments differ from devices in which one or more vents allow air to escape but not enter the drainage tube.

[0112] The urinary drainage lumen preferably has an inner diameter of less than about 0.25 inches (about 0.63 centimeters), which allows liquid within the lumen to circumferentially contact the lumen, forming a seal and allowing liquid to be advanced when the pumping mechanism is activated. Multiple drainage lumens may be provided to prevent flow interruptions if the pumping mechanism fails. In these embodiments, the drainage lumens are preferentially generally empty, which may require continuous activation of the pumping mechanism. Alternatively, the pumping mechanism may be activated before measuring the volume to ensure all liquid has been drained, thereby reducing the power requirements of the device.

[0113] Some embodiments of the sensing Foley catheter system include detecting a pressure spike in the drainage line while the pressure in the body organ is maintained constant, and using a pump to generate a negative pressure in the drainage line until the pressure in the drainage line equals the pressure in the body organ.

[0114] In one embodiment, the vent has a resistance to air flow that is greater than the resistance to fluid flow from the patient, so that any accumulation of fluid within the patient is purged into the drainage line before air enters through the vent. For example, in the case of urinary drainage, if the resistance to air through the vent is greater than the resistance to urine flow through the patient's catheter, a full bladder will empty into the urinary drainage line before air enters through the vent. However, to minimize aspiration trauma, it is preferable that the vent have as little resistance to air flow as possible while still meeting this requirement.

[0115] Alternatively, to further protect the bladder from aspiration, the vent may provide little resistance to airflow, and the controller pump may operate at more frequent intervals, such as every 1 minute, 5 minutes, or 10 minutes, to clear the airlock and keep the drainage line clear of urine. Once the pump is activated, it continues to operate until it detects no more urine output, indicating the bladder is completely emptied. Alternatively, the pump may operate for a set period of time, such as about 30 seconds, about 1 minute, about 3 minutes, about 5 minutes, or about 10 minutes. The controller pump may be inactive during the predetermined time interval and may generate a "background vacuum" (a negative pressure lower than the airlock clearance pressure) during the airlock clearance time interval.

[0116] The pumping mechanism used can be any suitable mechanism, including, but not limited to, a peristaltic pump, a diaphragm pump, a vane pump, an impeller pump, a centrifugal pump, or other suitable pump. The pump can be powered by a mains power source, a battery, human power, or other suitable power source. In some embodiments, the vacuum ranges from about 0 to -50 mmHg (about 0 to about -6.67 kPa). Alternatively, the negative pressure can be provided by a wall vacuum, such as those commonly found in hospital rooms. The pumping mechanism can include a peristaltic pump or suction applied directly to the collection container. While the pump may be located on the patient side of the drainage reservoir, the pump is preferably located on the non-patient side of the drainage reservoir / cassette, with the reservoir between the patient and the pump. To function properly, the pump should preferably be capable of generating a negative pressure equal to the maximum fluid column height in the drainage tubing, which may be half the length of the drainage tubing. For urinary drainage tubes up to 60 inches long, the maximum negative pressure required is approximately 30 inH2O or 56 mmHg.

[0117] Other techniques can be used to urge urine through the tube and / or system, including pulsatile mechanical, vibroacoustic, thermal, vibratory, pinching, rolling, or electromagnetic stimulation to cause movement of at least one of the drainage line and bodily fluid therein. In some embodiments, the rolling stimulation includes sequential compression of multiple lumens such that the lumens are never all compressed simultaneously.

[0118] In another example, the drainage lumen relief mechanism consists of tubing with an internal diameter of less than about 0.25 inches (about 0.64 centimeters) to prevent air pockets from migrating down the length of the tubing. This is because, when one end of the tubing is closed to the atmosphere (as in the bladder example), surface tension within the smaller tubing prevents fluid movement. Therefore, the drainage tubing is always full of urine, and because urine is incompressible, an equal amount of urine must exit the drainage tubing with each urination. In another example, the internal diameter is less than 0.125 inches (3.175 millimeters). In another embodiment, the drainage tubing acts as a siphon, applying a small, safe vacuum to the bladder. Alternatively, small-lumen drainage tubing may have a vent / valve that periodically allows air to enter the tubing lumen. This can be facilitated by a negative pump pressure. The negative pump pressure keeps urine flowing to the collection reservoir, preventing an airlock.

[0119] Additionally, the use of smaller diameter tubing results in less residual urine in the drainage tube compared to prior art. A smaller residual volume is preferable because it allows urine to move more quickly from the patient's bladder to the collection container. This transport speed is important for measuring more recently produced urine, especially in patients with low urine production, as it takes longer for urine to travel from the bladder to the collection container. For example, for a patient who produces only 10 mL per hour with a standard drainage tube (approximately 40 mL residual volume), measuring urine in the collection container will result in a 4-hour delay from actual urine production. On the other hand, for smaller tubes (tubes with approximately 5 mL residual volume), the measurement will only be delayed by approximately 30 minutes from actual production. In embodiments using a smaller diameter lumen, regardless of whether a vent / valve is present, a pump is not required to provide negative pressure to the drainage line.

[0120] FIG. 13 illustrates an embodiment of a device suitable for drainage tubes, such as chest tubes, that apply a constant negative pressure to a patient. These embodiments may also be suitable for draining urine from the bladder or fluids from other cavities. Any of the features disclosed in connection with chest tube drainage can also be applied to bladder drainage or other body cavity drainage. Fluids are drained from the patient through a drainage lumen 1585 that connects to a collection container 1382. Drainage is assisted by applying negative pressure to the collection container 1382, for example, by attaching a suction tube 1383 to hospital wall suction. Suction can also be achieved in other ways, such as with a pump as disclosed elsewhere herein. Air enters the drainage lumen 1385 through a valve 1384, which has a crack pressure equal to the desired negative pressure. By selecting the correct crack pressure (e.g., -15 to 0 mmHg (approximately -2 to 0 kPa), or -10 mmHg (approximately -1.33 kPa)), the pressure applied to the patient will remain at this pressure as long as the hospital wall suction / pump can generate sufficient suction in the collection container 1382. Preferably, the drainage lumen or lumens used to drain the chest tube are as large as possible while still maintaining a siphon. Suitable internal diameters include, but are not limited to, about 1 / 4 inch (approximately 0.64 centimeters), about 5 / 16 inch (approximately 0.8 centimeters), or about 3 / 8 inch (approximately 0.95 centimeters).

[0121] FIG. 14 illustrates another example device suitable for use with drainage tubes, such as chest tubes, that apply a constant negative pressure to a patient. Fluid is removed from the patient through a drainage lumen 1488, and negative pressure is applied using a pumping mechanism 1486. A pressure sensor 1487 is located within the patient-side drainage tube to measure the pressure applied to the patient. The measurement obtained by the sensor 1487 is returned to a controller that controls the pumping mechanism 1486, which adjusts the pressure generated by the pumping mechanism 1486 to maintain the desired pressure at the sensor 1487 (and the patient). The pressure sensor 1487 may also be located elsewhere in the system. This sensor could also be used to passively monitor the pressure on the patient side of the tube and provide the clinician with information about the level of suction being applied. While FIG. 14 shows the pump on the patient side of the drainage reservoir, the pump could alternatively be located on the opposite side of the drainage reservoir, with the reservoir located between the patient and the pump.

[0122] In another embodiment of the invention used for chest tube drainage, the volume of drained fluid is measured to provide the clinician with information regarding the status of the chest tube drainage. This measurement can be accomplished by any suitable means, particularly those described herein for measuring urine volume.

[0123] In addition to eliminating airlocks, some of the airlock elimination configurations described above have been found to effectively remove debris and clots from urinary drainage lines. These challenges plague current urinary drainage tube monitoring technologies, particularly for smaller lumen drainage tubes and drainage bags. The present invention advances the state of the art by automating the removal of debris and clots that obstruct drainage. This feature is particularly useful when combined with a pressure sensor in the Foley tip balloon or in fluid communication with the bladder. This allows for monitoring intrabladder pressure and vacuum and more aggressive fluid delivery based on actual bladder pressure until the clot / obstruction is resolved. Without this pressure / vacuum sensing, pumping fluid through the drainage tube can expose the bladder mucosa to excessive vacuum, potentially resulting in clinical consequences, such as aspiration trauma, within the bladder.

[0124] As shown in FIG. 15, the active vent system comprises an air vent 1502, a drainage line 1504, a collection container 1506, and a pump 1508. The vent side of the drainage line is connected to the patient. In one embodiment, the drained fluid is urine, and the connection is to a urinary catheter. 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 instead draws a vacuum on the collection container. The pump applies negative pressure to the collection container, forcing fluid into the drainage line and facilitating drainage. 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 gases (preferably air) but prevents the permeation of liquids. This vent prevents atmospheric air from entering the system and creating substantial negative pressure on the patient. This mechanism can prevent suction trauma, for example, to the bladder wall.

[0125] The pump in this system can be any pump suitable for pumping gas, including, but not limited to, peristaltic, diaphragm, or centrifugal pumps. For the pump to function properly, it is preferable that it be capable of generating a negative pressure equal to the maximum fluid column height in the drainage tubing, which may be half the length of the drainage tubing. For urinary drainage tubing up to 60 inches long, the maximum negative pressure required is approximately 30 inH2O or 56 mmHg (approximately 7.47 kPa).

[0126] As shown in FIG. 16, an active vent system for draining bodily fluids may include additional vents. One such vent, vent 1662, may be located in the collection container to allow air to escape from the collection container. This prevents pressure buildup by offsetting each new volume of fluid entering the container with an equal volume of air leaving the system. Another such vent, vent 1664, may be located between the collection container and the pump. This vent allows the transmission of gases (preferably air) but prevents the transmission of liquids, preventing bacteria and viruses from entering or exiting the collection container and drainage tube. Preferably, this vent is sterile-grade, meaning the air passing through is considered sterile. A vent (not shown) may or may not be located on the patient side of the drainage line.

[0127] As shown in FIG. 17, pressure cancellation can be achieved with a single vent on the collection reservoir. In this case, a vent 1772 may be provided between the collection reservoir and the pump as before, but an additional valve 1774 allows air to escape from the collection reservoir in the presence of positive pressure. This valve is preferably a one-way valve that allows air to leave the system but not enter. When the pump is activated, the one-way valve closes, and air must be drawn from the collection reservoir, creating negative pressure within the collection reservoir and encouraging fluid flow through the drainage line. A vent (not shown here) may or may not be provided on the patient side of the drainage line.

[0128] Infectious disease detection

[0129] FIG. 18 illustrates an embodiment of a collection container, chamber, or cassette that may be included in a Foley catheter system for detecting bacteria, blood, and / or other substances in urine using UV / Raman spectroscopy. Cassette 1800 includes a preferably rigid container wall 1802. Urine 1806 collects in the cassette. An overflow area 1804 allows any excess urine to drain from the cassette if urine collects too quickly or if the cassette is unable to empty or empty quickly enough (e.g., in high urine flow situations). Cassette 1800 may include an optically transparent section 1810, preferably incorporated into the outer wall of the cassette, and a reflective section 1812, preferably on or incorporated into the inner wall of the cassette. "Optical transparency" in this context means that light of the required analytical wavelength(s) can be transmitted through the optically transparent section. The optically transparent section is preferably formed of a material that is transparent to UV light, such as polymethylmethacrylate, polystyrene, acrylic, or quartz. The wall thickness may need to be thin enough to allow the appropriate ultraviolet wavelength or wavelengths to be transmitted through the optically transparent section. For example, the optically transparent section may have a thickness of about 0.5 mm to about 0.7 mm. Alternatively, the optically transparent section may have a thickness of about 0.5 mm to about 0.6 mm. Alternatively, the optically transparent section may have a thickness of about 0.6 mm to about 0.7 mm. Alternatively, the optically transparent section may have a thickness of less than about 0.7 mm.

[0130] The UV / light transceiver 1808 transmits the appropriate wavelength of UV or other light through the optically transparent portion 1810, through the urine in the cassette, and onto a reflector 1812 in the cassette. The UV / light transceiver may be integrated into or connected to the control component of the Foley catheter system. The light is reflected back to the UV / light receiver, and the collected data is transmitted to the control for signal analysis. Multiple wavelengths of UV / light can be analyzed simultaneously or sequentially. Light can be used outside the UV range as well as within the UV range. The amount of urine physically present between the transmission and reception of the light is preferably maximized to produce a stronger signal reflecting the concentration of one or more substances in the urine. The transceiver may be positioned as shown in FIG. 18 or in other areas of the cassette. The receiver may be located separately from the transmitter, and a reflector may or may not be required. As the urine in the cassette is emptied frequently, UV / light absorption measurements can be collected over time to track the increase or decrease in the level of one or more substances in the urine in essentially or near real time. This is especially important for early identification of infections such as urinary tract infections and catheter-associated urinary tract infections (CAUTIs). Ultraviolet / light detection can also be performed at other points in the Foley catheter system for detection, such as the drainage tubing or separate sampling areas.

[0131] Infectious diseases can be identified by analyzing bacteria, red blood cells, plasma, and / or white blood cells in urine using ultraviolet / light spectroscopy. Figure 19A illustrates the various wavelengths of light absorption of E. coli, red blood cells, and plasma in urine. The presence of plasma / white blood cells and / or bacteria in urine are all indicators of infection. The presence of red blood cells may not indicate an infection. Therefore, it is desirable to distinguish between red blood cells and bacteria / plasma / white blood cells in urine. Because red blood cells have significantly different spectroscopic characteristics from bacteria and plasma / white blood cells, an infection can be identified by separating the red blood cell signal from the bacterial and / or plasma / white blood cell signals at a wavelength of approximately 414 nm and analyzing the absorption of light at this wavelength. Because plasma and bacteria have different signatures at wavelengths of 260 nm and 280 nm, these wavelengths can be used to distinguish between plasma and bacteria. However, both plasma and bacteria may be present during an infection.

[0132] Broadband spectroscopy can be used over a continuous wavelength range and time course. Deconvolution or demixing of the signal can determine the amount of an analyte and / or form the basis of a signature for developing analytical algorithms.

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

[0134] Visible wavelengths can also be used. For example, a camera capturing visible light can be used to monitor collected urine over time. Images collected by the camera can be analyzed for color wavelength, turbidity, color intensity, consistency or inconsistency in color and / or intensity and / or turbidity, cloudiness, presence of blood or blood clots, hemolysis, air bubbles, protein, etc. Urine images can be captured at virtually any time interval over a period of hours to days, allowing the urine to be monitored for the presence or absence of factors indicative of a patient's condition or changes in the patient's condition. For example, dehydration (based on the degree of yellowness of the urine), bleeding (based on the presence of blood), protein in the urine (based on bubbles in the urine), and congestion (based on cloudiness, bubbles, color, turbidity, etc.) can be identified. When using a camera to evaluate characteristics of collected urine over time, it can be important to evaluate small amounts of the most recently collected urine to avoid dilution with older urine samples. This can provide substantially real-time feedback on the patient's condition. To accomplish this, the camera may be aimed at an inlet portion of the cassette 1800, for example, at the bottom of the drainage tube, or at the top of the cassette, or where the drainage tube connects with the cassette.

[0135] A reference color may be included in the system, such as a cassette, to calibrate the camera to the reference red, blue, and green colors. For example, red, green, and blue reference areas (such as a reference sticker with red, green, and blue areas) may be placed near the camera (inside or outside the cassette) and on the other side of the cassette so the camera can see both. The near reference calibrates the camera to the color in the absence of urine, and the far reference will be the same color as seen by the camera through urine.

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

[0137] The control unit can alert the user if the camera detects something outside of a preset range, such as if the urine color is outside of a normal range, the system tilt is outside of an acceptable range, the system changes the tilt angle more frequently than a preset frequency, the urine turbidity is outside of a normal range, or blood or other abnormal presence is detected in the urine.

[0138] In embodiments where a visible wavelength camera is used, a live or semi-live feed of urine within the system can be remotely displayed. For example, the urine reservoir / cassette can be displayed on a table, computer, phone, monitor, etc. in the room. This capability allows the urine in the reservoir and / or urine bag to be hidden in close proximity to the patient, which may be more comfortable for the patient and their visitors. That is, the actual urine in close proximity to the patient can be hidden or covered with an opaque material, while the image feed of the urine is displayed elsewhere. The urine contained in some or all of the cassette, drainage tubing, urine bag, etc. may be hidden by an opaque material.

[0139] FIG. 19B shows an embodiment of a display 1110 on the controller / monitor 1018, including current and historical trends for IAP, temperature, urine volume, and urine color. Urine color may be detected via a camera as disclosed herein. While shown in black, white, and grayscale, actual colors such as yellow, orange, and red may be displayed. Settings 1902 may be available to display different historical ranges of data, including 1 hour, 6 hours, 12 hours, 24 hours, and so on. Clicking on the small color boxes to expand them allows users to see actual photographic images or videos of the urine color, cloudiness, turbidity, bubbles, etc. at that time.

[0140] The embodiments disclosed herein illustrate a user interface display on a controller / monitor. However, the display, or components of the display, or the collective display, can additionally or alternatively be displayed on a computer, mobile computer, cell phone, tablet, another monitor / screen, etc. For example, a portion of the display can be displayed on a portable tablet, which can be used independently or docked with the controller / monitor. Devices such as tablets and cell phones can be synchronized with the controller using proximity, RFID, or other methods. The display can display information about an individual patient and / or, for example, at a nurse's station, can display information about multiple patients. The display can display data for multiple patients individually or aggregated across multiple patients. The display can also incorporate multiple different screens, which can be accessed by switching between them. Some screens / displays may require administrator login authentication, such as for adjusting Foley system settings.

[0141] Alternatively, or in addition, mechanisms such as RFID can be used to prevent the use of unauthorized, "pirated" disposable portions of the system. In this way, the controller / monitor can recognize disposable portions of the system as authorized or unauthorized. The system may alert the user and may not function in the presence of unauthorized disposable portions. Similar ID mechanisms can also be used to control system functionality. For example, a user may pay a subscription fee to access the IAP functionality of the system. The same disposable unit can be used by both those who subscribe to the IAP functionality and those who do not, but the controller can be programmed to reflect the subscription details, and the ID mechanism may allow the disposable IAP functionality to function for those who subscribe to the functionality. Due to the ID mechanism, the IAP functionality may not function for those who do not subscribe to the functionality. Alternatively, the controller can allow the functionality to function only once or a limited number of times for those who do not subscribe to the functionality.

[0142] Using appropriate sensors, drugs or drug residues can be detected in collected urine. Various substances or properties of collected urine can be detected, including color, clarity, odor, specific gravity, osmolality, pH, protein, glucose, creatinine, nitrite, leukocyte esterase (WBC esterase), ketones, red or white blood cells, mold, crystals, bacteria, yeast cells, parasites, and squamous epithelial cells.

[0143] CAUTI or infection can be identified and / or reduced by several methods, including analyzing urine using spectroscopy, optical wavelength analysis, etc., identifying contaminants early, reducing trauma to the bladder caused by suction, reducing urinary retention in the bladder, reducing the presence of bacteria or microorganisms by using antimicrobial coatings or implants of materials such as silver, improving the accuracy of intrabladder pressure measurements by reducing suction in the bladder, and improving the accuracy of urine volume measurements by reducing airlocks and suction in the system. A bladder suction pressure spike can be defined as a pressure measurement below about −20 mmHg (about −2.67 kPa). Alternatively, a bladder suction pressure spike can be defined as a pressure measurement between about −10 mmHg and about −20 mmHg (about −1.33 kPa to about −2.67 kPa). Alternatively, a bladder suction pressure spike can be defined as a pressure measurement below about −10 mmHg (about −1.33 kPa).

[0144] CAUTI can also be reduced by using ultraviolet light, or any effective wavelength of light or radiation, to reduce bacteria in the urine and / or the system. Urine can also be treated using UV light to disinfect the urine in the cassette or elsewhere in the system. For example, UV light can disinfect the urine as it enters the cassette, such as at the inlet valve 4104 as shown in FIG. 41A, or within the cassette, or on the cassette, such as in the drainage tubing above the cassette.

[0145] Figure 20 shows a cassette according to one embodiment that includes a septum or flap 2002. This septum / flap prevents urine from seeping along the interior walls of the cassette, as indicated by the dotted arrow. By preventing urine from seeping past the septum, urine falls back into the measurement reservoir below.

[0146] Priming

[0147] An aspect of the disclosed technology that is particularly advantageous for achieving high-resolution signals capable of monitoring pressure profiles from specific physiological sources (such as peritoneal pressure, respiratory and heart rates, relative pulmonary tidal volume, cardiac output, relative cardiac output, and absolute cardiac output) relates to adjusting and maintaining a pressure balance on both sides of the pressure interface represented by the membrane of the pressure-sensing balloon. This pressure balance may be referred to as a differential pressure. In some embodiments, the preferred differential pressure is at or near zero. In some embodiments, the preferred differential pressure may be a different value. The pressure on the outer surface of the balloon (the surface facing the inner bladder surface) varies depending on the physiological state of the patient. The pressure on the inner surface of the balloon (the surface in fluid communication with the fluid column) is subject to degradation due to fluid leakage and imperfect seals.

[0148] When the sensing Foley catheter is first inserted, external pressure is typically applied to the fluid column, applying a first approximation to the pressure applied to the pressure interface from within the bladder. A pressure signal is measured across the pressure interface and has a maximum amplitude when the differential pressure is approximately zero. The amplitude of the pressure signal can then be used to adjust the pressure applied to the pressure interface from the fluid column. This application of appropriate pressure to the interface is sometimes referred to as priming the fluid column or priming the balloon. Because the pressure on both sides of the pressure interface changes as described above, the fluid column must be reprimed or reconditioned from time to time. The need for re-aspiration can be monitored by testing small pressure changes to maximize the pressure signal profile. Alternatively, priming can be performed automatically via the controller periodically.

[0149] Embodiments of the disclosed systems and methods include automatic pressure adjustment by the controller. Thus, the adjustment system can detect optimal target pressure and volume for balloon inflation by monitoring the sensed pressure signal and adding or removing air or fluid volumes as needed. For example, during catheter insertion, a pressure adjustment circuit that adjusts balloon volume and pressure can inflate the balloon until it detects a physiologically based pressure rate. Once the pressure rate is detected, the pressure adjustment controller can add or subtract small amounts of air in a routine or programmed series of steps until the amplitude of the sensed wave is maximized. The control feedback loop between the optimally adjusted pressure (manifested as balloon pressure and volume) and the sensed physiological pressure profile is repeated continuously or as needed to ensure high-fidelity measurement of physiological data. In some embodiments, the automatic pressure adjustment can run in the apparent background while physiological data is transmitted and displayed. In other embodiments, the system can pause transmission of physiological data during the pressure adjustment sequence.

[0150] An embodiment of the disclosed technology includes a gas supply system capable of supplying gas via a priming operation, whereby pressure can be applied to a fluid column proximal to the proximal-facing side of a pressure interface. A source of gas, such as compressed air or liquid, is held in a storage tank. Using CO2 as an example, CO2 is controllably released from the storage tank through a pressure regulator that can reduce the pressure within the tank (e.g., approximately 850 psi (approximately 5.86054 MPa)) to a range of approximately 1 psi (approximately 6.9 kPa) to approximately 2 psi (approximately 13.8 kPa). The released gas passes through a filter and a pressure relief valve set at approximately 2.5 psi (approximately 17.2 kPa). The pressure relief valve is a safety element that prevents gas levels above 2.5 psi (approximately 17.23 kPa) from flowing in the event of an upstream regulator failure. The CO2 exiting the pressure relief valve then passes through a first solenoid-controlled fill valve into the catheter line, ultimately filling the balloon that forms the pressure-sensing interface. When the pressure inside the balloon rises to 30 mmHg (approximately 4 kPa), the first solenoid 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 the target pressure. Alternatively, the drain valve can be activated until a respiratory waveform is detected, after which the balloon is optimally primed and the valve is closed. The drain valve can be proportionally controlled, operationally based on voltage or pulse-width modulation (PWM), allowing a drain rate slow enough to close the valve before the target pressure is reached and overshoots. Alternatively, an air pump, such as a peristaltic pump, can be used to fill the balloon with room-temperature air.

[0151] FIG. 21 is a graph illustrating a method for priming a pressure balloon in some embodiments. Here, a small volume burst of fluid (roughly about 0.3 cc) is added to a pressure-sensing balloon and the pressure inside the balloon is measured. Small bursts of fluid are introduced until the measured pressure inside the balloon settles to a stable pressure 2101. This transition is indicated by inflection point 2102. After this point, volume bursts are introduced until the measured pressure begins to rise sharply (e.g., when the slope 2104 of the curve is greater than about 2 mmHg (about 266.645 Pa) / 10 ms). This inflection point is indicated by 2106. At this point, the pressure inside the balloon is reduced to near or slightly above the stable pressure 2101. This pressure represents the primary pressure measurement pressure in some embodiments. This process is also illustrated in the flowchart of FIG. 24.

[0152] Alternatively, priming the pressure balloon may involve pressurizing the pressure balloon well above 0 mmHg (0 Pa), followed by releasing a small amount of air / gas / fluid and monitoring the pressure in the pressure balloon. The pressure in the pressure balloon will stabilize, or plateau, as it approaches the optimal priming pressure. To determine this optimal pressure, pressure measurements are taken while releasing a small amount of air from the pressure balloon; if the subsequent pressure measurements are essentially the same (within about 2 mmHg (about 0.267 kPa) of each other), the balloon is at the optimal priming pressure. If the two measurements are not equivalent, the pressure balloon is re-pressurized well above 0 mmHg (0 Pa) and the process is repeated. The pressure measurement taken with a small amount of air released from the pressure balloon may take approximately 5 to 15 seconds to compensate for the effects of breathing on the pressure measurement. In some embodiments, the pressure signal may require a short stabilization period after the small amount of air / gas / fluid is removed from the pressure balloon before a pressure measurement is taken.

[0153] A small burst of fluid may be ejected, such as about 0.2 cc to about 0.4 cc. A small burst of fluid may be ejected, such as about 0.1 cc to about 0.5 cc. A small burst of fluid may be ejected, such as up to about 0.5 cc. A small burst of fluid may be ejected, such as up to about 1.0 cc.

[0154] FIG. 22 is a graph illustrating a method for priming a pressure balloon in some embodiments. This method is similar to the method illustrated in FIG. 21, except that the pressure in the pressure-sensing balloon increases more smoothly, without the burst illustrated in FIG. 21. Fluid is introduced into the pressure-sensing balloon, and the pressure in the balloon is measured. The balloon pressure is increased until the measured pressure in the balloon settles to a stable pressure 2205, indicated by inflection point 2206. The balloon pressure is increased beyond this point until the measured pressure begins to rise sharply (e.g., when the slope 2210 of the curve is greater than approximately 2 mmHg (approximately 266.645 Pa) / 10 ms). This inflection point is indicated by 2208. At this point, the pressure in the balloon is reduced to near or slightly above the stable pressure 2205, which in some embodiments corresponds to the optimal, or prime, pressure. This process is also illustrated in the flowchart of FIG. 25.

[0155] FIG. 23 is a flowchart illustrating a balloon priming process according to an embodiment of the present invention. An embodiment of the disclosed system and method includes automatic pressure adjustment by a controller. Thus, the adjustment system can detect an optimal target pressure and volume for balloon inflation by monitoring the detected pressure signal and adding or subtracting air as needed. For example, once the catheter is inserted, a pressure adjustment circuit, which adjusts the balloon volume and pressure, inflates the balloon until it detects a physiologically based pressure ratio. Having detected the pressure ratio, the pressure adjustment controller adds or subtracts minute amounts of air or fluid (roughly about 0.3 cc) in a routine sequence until the detected wave amplitude is maximized. The control feedback loop between the optimally adjusted pressure (manifested as balloon pressure and volume) and the detected physiological pressure profile is repeated continuously or as needed to ensure high-fidelity measurement of physiological data. In some embodiments, the automatic pressure adjustment may run in the apparent background while physiological data is transmitted and displayed. In other embodiments, the system may pause transmission of physiological data during the pressure adjustment sequence.

[0156] The minute amount of air or liquid can be from about 0.2 cc to about 0.4 cc. The minute amount of air or liquid can be from about 0.1 cc to about 0.5 cc. The minute amount of air or liquid can be up to about 0.5 cc. The minute amount of air or liquid can be up to about 1.0 cc.

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

[0158] Loop Control Section

[0159] Certain patient parameters measured by a sensing Foley catheter system or other means are affected and / or influenced by treatment of the patient with a medical treatment device.

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

[0161] For example, IAP can be used to control the infusion rate of an intravenous fluid. If the IAP becomes too high, the infusion rate can be reduced or stopped until the IAP returns to an acceptable range. Combining IAP with relative stroke volume and / or stroke volume variability (e.g., the variation in the magnitude of the bladder pulse during the respiratory cycle) can provide a superior method for controlling intravenous fluid infusion or blood product infusion, with IAP as an indicator of fluid overload and an increase in relative stroke volume and a decrease in stroke volume variability as indicators of the need for additional fluid infusion. Urine output may also be added to the control loop, with recovery of urine output indicating restoration of fluid status. The combination of heart rate and respiratory rate may also be used to control drug infusion (e.g., type of drug, infusion rate, frequency, dosage). In this way, medications may be used to achieve a more stable patient state, as determined by heart rate and respiratory rate. IAP and respiratory rate may also be used to control mechanical ventilators and respirators. As IAP increases, the positive end-expiratory pressure (PEEP) delivered by the mechanical ventilator should also increase to overcome this pressure. Indicators of insufficient ventilation can be seen in tissue oxygenation and / or spontaneous breathing rate, which can be considered the underlying signal for mechanical ventilation. This signal can be extracted during mechanical ventilation, or, preferably, the loop controller can pause the mechanical ventilator to allow for more precise and accurate detection of the underlying respiratory rate / drive. This IAP, tissue oxygenation, and / or respiratory rate can be used to alert the healthcare provider to a worsening patient condition and / or to automatically adjust ventilator settings, including respiratory rate, PEEP, inspired % O2, and other settings. In an ideal scenario, these parameters could be used by the loop controller to monitor and control therapy, informed by machine learning and algorithmic adjustments. These are just a few examples; many combinations exist. One or more parameters could be used to control one or more treatment devices.

[0162] 26 illustrates a loop control according to one embodiment in a patient environment. In this example, the loop control receives patient parameter input from a sensing Foley catheter 2602. The sensing Foley catheter resides in the patient's bladder 2604 and includes a retention balloon 2608 and a pressure sensing balloon 2610. The sensing Foley catheter may include other sensors as disclosed herein.

[0163] The sensing Foley catheter 2602 includes a retention balloon inflation lumen, a pressure balloon sensing lumen, and a urine lumen. The pressure sensing balloon 2610 is connected to the pressure sensing lumen, which is connected to a pressure transducer 2620, which may be integrated into a controller 2628. The urine lumen is connected to a urine output tubing 2612. The urine output tubing empties into a urine reservoir 2614, which may be connected to a urine volume measurement device 2616 or may be integrated into the controller as disclosed herein. Additionally, urine volume may be controlled by a urine pump 2618, which may be located on the urine drainage tubing, integrated into the controller, or located on the non-patient side of the controller as disclosed elsewhere herein.

[0164] The patient is shown equipped with a respirator mask 2622 fed by a respirator tube 2624. The flow and quality of the respiratory gas is controlled by a respirator 2626.

[0165] Loop controller 2628 is connected to urinary flow measurement device 2616, urine pump 2618, pressure transducer 2620, and respirator 2626 via connectors 2630, 2632, 2634, and 2636, respectively. The connectors may be wired or wireless. Alternatively, in this and other embodiments, some or all of urinary flow measurement device 2616, urine pump 2618, and / or pressure transducer 2620 may be incorporated into controller 2628.

[0166] In this example, the loop controller 2628 can receive patient parameter inputs from the urinary flow measurement device 2616 and the pressure transducer 2620 and use the information provided by these parameters to control the urine pump 2618 and the respirator 2626. Some parameters that the loop controller can receive from the sensing Foley catheter include IAP, respiratory rate, heart rate, cardiac output, tissue oxygenation, tissue perfusion pressure, body temperature, urine analytes, urine output rate, and other parameters including those disclosed herein.

[0167] For example, if the loop controller receives parameter information indicating that the patient's IAP is elevated, the loop controller can control the respirator irrigation rate, pressure, or other parameters. The loop controller can take data from one or more input parameters and control one or more treatment medical devices. For example, based on the received elevated IAP and abnormal tissue oxygenation parameters, the loop controller can control the output of the respirator 2626 and also control the urine output rate by controlling the urine pump 2618.

[0168] The loop controller continuously monitors one or more patient parameters and adjusts one or more treatment devices accordingly. When the patient parameters normalize, the control of the treatment devices is adjusted accordingly, resulting in a closed feedback loop controlled by the loop controller. The loop can also be manually adjusted as needed, resulting in an open or semi-closed loop.

[0169] FIG. 27 shows another example of a loop controller in a patient environment. In this example, the patient has an intravenous (IV) line 2702 in a vein in the arm. An IV fluid bag 2704 is elevated to allow IV fluid to drip and / or flow into the patient through the IV line 2702. A valve 2706 controls the flow of IV fluid to the patient by allowing the fluid to flow freely, restricting the flow, or stopping the flow. Here, the valve 2706 is controlled by the loop controller 2628 via a connection 2708. The IV fluid bag 2704 can contain hydration fluid and / or medication. One or more IV bags may be involved, and one or more valves may control the IV bag(s). The loop controller can control the flow rate and composition of the intravenous fluid(s) to the patient based on patient parameters received by the loop controller.

[0170] 28 shows another example of a loop control unit in a patient environment. In this example, a patient has a fluid drainage line 2802 inserted into their abdomen. Fluid from the abdomen may flow from the patient to a receptacle 2804. The fluid flow may be controlled by a pump 2806, which is controlled by the loop control unit 2628 via a connection 2808. The loop control unit may control the flow of fluid from the patient through the pump 2806 to the receptacle 2804 based on received patient parameters. For example, if the IAP is abnormally high, the loop control unit may increase the rate or initiate fluid removal from the patient by controlling the pump 2806.

[0171] FIG. 29 shows another example of a loop control unit in a patient environment. In this example, the patient has an intravenous (IV) line 2902 in a vein in the arm. A drug infusion device 2904 controls the flow rate of a drug into the patient through the IV line 2902. Multiple drug infusion devices may be used, where drug infusion devices 2904 are controlled by loop control 2628 via connection 2906. Drug infusion device 2904 may include any suitable fluid and / or drug. The loop control may control the flow rate and composition of one or more drugs to the patient based on patient parameters received by the loop control.

[0172] These examples are only a partial list of medical treatment devices that can be controlled by the loop control unit, but any medical treatment device can be used.

[0173] FIG. 30 is a detailed diagram showing the loop control. The loop control 2628 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 volume and rate, a pressure profile from the bladder, and sensor information from devices such as a sensing Foley catheter. The pressure profile information from the bladder can be further analyzed to measure IAP, respiratory rate, heart rate, cardiac output, sepsis index, acute kidney injury index (AKI), and other patient parameters. This analysis can be performed in the loop control 2628 or in a separate controller connected to the loop control by either a wired or wireless connection. The connection can be over a network such as the Internet, an intranet, a WAN, a LAN, or the like, or locally via Bluetooth, Wi-Fi, etc.

[0174] The loop controller receives one or more inputs and analyzes the data to determine whether changes to the control of the medical treatment device are necessary. One or more medical treatment devices may be controlled to bring a patient parameter into a target range. Once the patient's target range is achieved, the loop controller can return the controlled one or more medical treatment devices to a standard condition. The standard condition will vary from one medical device to another and from one patient to another. The target ranges for the patient parameters will similarly vary from patient to patient and depending on the patient's condition. For example, a respirator's target respiratory rate range may differ depending on whether the patient is sedated.

[0175] Embodiments of the present technology can also automatically adjust intravenous fluid or drug infusion rates based on feedback from sensed cardiac output or respiratory rate. In one such embodiment, a patient-controlled analgesia pump can be shut off if the respiratory rate drops too low. Respiratory depression can be fatal in this population, and this safeguard can prevent overdose. An automated feedback system can also be advantageous in large-volume resuscitation procedures, adjusting fluid infusion based on intra-abdominal pressure and issuing a warning if intra-abdominal pressure increases, slowing the fluid infusion rate to prevent abdominal compartment syndrome. Yet another automated feedback function can provide direct feedback to the ventilator system to ensure optimal ventilation gas pressure. When abdominal pressure increases, typical ventilator settings may not provide sufficient ventilation for the patient. Automatic adjustment of ventilator settings based on intra-abdominal pressure feedback from this embodiment can advantageously provide optimal patient ventilation. Embodiments of the present technology can also be applied as corrections in other diagnostic measurement applications and understandings. For example, increased intra-abdominal pressure can significantly distort central venous pressure. By allowing central venous pressure reporting systems direct access to these data, this critical physiological parameter can be automatically corrected and accurately reported. Additionally, embodiments of the present technology can be used in a variety of other ways to automate therapy, such as infusing fluids containing additional active agents such as vasopressors or diuretics, in response to increases or decreases in cardiac output or other parameters.

[0176] Other inputs and outputs to the loop controller include nutrition provided via a feeding tube or intravenous route, wound drainage, bowel movements, chest drainage, sweating, and exhaled vapor. Sweating may be assessed by measuring body temperature, ambient temperature, and humidity, or, in the case of mechanically ventilated patients, by measuring inspired temperature and humidity. Alternatively, or in addition, a skin sweat sensor may be used.

[0177] In addition to directly controlling one or more medical treatment devices, the loop control 2628 can also sound alarms, including audible alarms, email alarms, text alarms, pager alarms, etc. The loop control 2628 can also provide outputs to other systems for system integration, such as outputting information to a lifetime electronic health record (EHR) or other data archiving system or other system. The loop control 2628 can also receive inputs from various EHR, EMR, or other systems.

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

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

[0180] specific gravity

[0181] Urine specific gravity can be measured by manometry and ultrasound using a sensing Foley catheter. Figure 34 is a plot showing how ultrasound and manometry volume measurements diverge with fluid concentration. The fluid being measured is concentrated synthetic urine, which has a specific gravity of approximately 1.100.

[0182] For a liquid with a specific gravity of 1.000, the two measurement techniques are calibrated to provide the same volume measurement. However, as concentration increases, the two begin to diverge. For pressure, V=A*h, P=ρ*g*h, i.e., V=A*ρ*g / P, so an increase in concentration results in an increase in the volume measurement. For ultrasound, V=A*h, v=h*2 / t, and v=(E / ρ)^(1 / 2), so an increase in concentration results in a decrease in the volume measurement, i.e., V=A*(E / ρ)^(1 / 2)*t / 2. V: Volume A: Cross-sectional area h: height of liquid P: Pressure ρ: liquid concentration g: gravity v: velocity of sound t: the time it takes for the sound to reflect E: bulk modulus of the liquid

[0183] Simply put, as the concentration of a liquid increases, the pressure increases, causing the reading to be biased upward. At the same time, the speed of sound propagation increases, distorting the ultrasound reading downward. By measuring the deviation, the concentration of the liquid can be determined. This assumes that the temperature remains constant, but it is also possible to monitor the temperature and correct for temperature fluctuations. A detection Foley catheter can measure volume using ultrasound and pressure, as well as body temperature. Thus, by combining a detection Foley catheter with a control unit, urine specific gravity can be measured.

[0184] Detecting / judging specific conditions

[0185] Figure 31A is a table listing multiple combinations of parameters that allow for fingerprints or signatures (one combination of multiple parameters) for different indicators of AKI (prerenal, intrinsic, and obstructive). Additionally, there may be fingerprints or signatures for the timing of parameter changes, which may identify the cause of AKI (e.g., it is plausible that some parameters change more quickly in intrinsic AKI due to glomerulonephritis than intrinsic AKI due to acute tubular necrosis). Furthermore, because effective treatments vary depending on the cause of AKI (e.g., recombinant alkaline phosphatase is effective for intrinsic (septic) AKI but not for non-septic AKI), this multiparameter approach may facilitate the selection of effective therapies for treating AKI.

[0186] Figure 31B is a table listing multiple combinations of parameters that allow for fingerprints or signatures (one combination of multiple parameters) for different indicators of sepsis, AKI, and acute respiratory distress syndrome (ARDS). These signatures involve increases, decreases, or both in various patient parameters, such as urine output, heart rate, respiratory rate, temperature, cardiac output, and abdominal perfusion pressure. Abdominal perfusion pressure is the mean arterial pressure (MAP) minus the intraperitoneal pressure (IAP). Mean arterial pressure is the diastolic pressure (DP) plus one-third of the pulse pressure (PP). (Pulse pressure is the systolic pressure minus the diastolic pressure.) MAP = DP + 1 / 3 PP.

[0187] Other patient parameters may also be used. One, some, or all of the relevant parameters may be used by the controller to communicate a diagnosis and / or risk to the user or other devices. Patient parameters acquired by the sensing Foley catheter system may be used alone or in combination with parameters acquired elsewhere, such as information from an electrocardiogram, a blood pressure measurement device, or an EMR.

[0188] Foley catheter systems can automatically and accurately monitor physiological parameters in real time for the early detection of various disease states. By utilizing real-time multivariate analysis (point values) and time series analysis (trends) of these high-frequency data streams in machine learning-based models, sensitive physiological signatures can be developed for the early detection of sepsis (or other disease states). This allows for earlier diagnosis and intervention, leading to improved clinical outcomes. Data signatures of physiological changes occurring before and / or during the onset of a specific disease state can be continuously refined through machine learning via artificial neural networks, strengthening relevant parameters and weakening less relevant parameters, building or breaking connections. This allows the control system to utilize algorithms that distinguish disease states from one another and normal from other disease states.

[0189] Some embodiments of the present invention can measure urine output immediately after a patient is administered a diuretic. This type of test can be a strong indicator of whether an AKI patient will progress to a more severe stage and / or die. If a patient's urine output increases after diuretic administration, this indicates a low likelihood of AKI becoming more severe. If a patient's urine output does not increase significantly after diuretic administration, this indicates a high likelihood of AKI becoming more severe. The present invention can rapidly and accurately measure urine output in real time. This allows for a response to diuretics to be detected more quickly (within minutes rather than hours) than traditional urine measurement methods.

[0190] This test can be automated with a controller that controls the diuretic dose and subsequently monitors urine output over minutes to hours, preferably only minutes. The diuretic administered can be furosemide or another suitable loop diuretic or other diuretic. The diuretic can be administered and data collected as disclosed in Chawla LS, Davison DL, Brasha-Mitchell E, Koyner JL, Arthur JM, Tumlin JA, Shaw AD, Trevino S, Kimmel PL, Seneff MG. Development and standardization of a furosemide stress test to predict the severity of acute kidney injury. Crit Care. 2013 Sep 20;17(5):R207, which is incorporated herein by reference in its entirety.

[0191] In addition to detecting AKI, the present invention can detect urinary tract infection (UTI) based on indicators such as decreased oxygen tension, decreased carbon dioxide concentration, increased specific gravity, and relatively stable urine volume and conductance. Detection of UTI is possible in the absence and, in some cases, presence of AKI by combining urinary markers for a UTI fingerprint. The UTI fingerprint can alert clinicians to the presence of a UTI.

[0192] In addition to detecting AKI and UTI using the parameters described above, these parameters can be used in combination with measurements of intra-abdominal pressure (IAP), respiratory rate (RR), heart rate (HR), cardiac output (CO), relative cardiac output (RSV), body temperature (Temp), pulse pressure (PP), urinary conductance (UC), urine volume (UO), and / or cardiac output (SV), which are measurements already used to detect intra-abdominal hypertension (IAH), abdominal compartment syndrome (ACS), and sepsis. Adding measurements of IAP, RR, HR, CO, RSV, Temp, PP, UC, UO, and / or SV to the algorithms described herein can improve the sensitivity and specificity of detecting AKI or UTI. Meanwhile, adding measurements obtained by the present invention to the measurement algorithms for IAP, RR, HR, CO, RSV, Temp, PP, UC, UO, and / or SV can improve the sensitivity and specificity of detecting IAH, ACS, or sepsis. It is also used clinically for the treatment of trauma and burns.

[0193] In addition to absolute measurements of IAP, RR, HR, CO, RSV, Temp, PP, UC, UO, gas concentrations, and / or SV, trend data for these parameters can also be used to detect IAH, ACS, sepsis, or other conditions. For example, the trend of these parameters over time and / or the variability of these parameters over time can also be used. Examples of data trending include pulse pressure waveform analysis and pulse wave velocity (or pulse transit time). Pulse transit time can be measured by acquiring an electrocardiogram (ECG) or other electrocardiogram signal from leads on a Foley catheter and / or other locations and measuring the time it takes for the pulse wave pressure signal to transit to the bladder. Multiple parameters and / or parameter trends can be used to determine the presence or absence of conditions such as IAH, ACS, or sepsis.

[0194] Examples of how trend data can be used include:

[0195] -Decreased UO2 with otherwise stable vitals may indicate acute kidney injury. Decreased cardiac output may indicate renal ischemia. Rapid increase in urine output with stable vitals may indicate toxic acute kidney injury.

[0196] -Decreased cardiac output with increased respiratory rate may indicate pulmonary embolism, hemorrhage, or other volume loss.

[0197] An increasing respiratory rate in the presence of stable vital signs may indicate impending airway obstruction.

[0198] - A decreased respiratory rate, despite stable other parameters, may indicate an overdose of sedatives, which poses a major challenge to the patient's analgesic control.

[0199] -Increasing intra-abdominal pressure (IAP) in the setting of stable cardiac output and increasing urinary output can be an indicator of impending fluid overload.

[0200] Increased IAP in the setting of decreased UO2 and reduced cardiac output may be an indicator of cardiopulmonary dysfunction, which may be due to fluid overload, sepsis, etc.

[0201] The present invention can be used in various hospital settings (e.g., emergency room, operating room, intensive care unit, ward). At any time, the device can be used to monitor the progression of AKI and whether it is improving or decreasing. The algorithm functions to alert clinicians to new cases of AKI or changes in AKI status. The device can also be configured to detect the onset of AKI before kidney damage occurs (e.g., to detect whether kidney damage begins during a cardiac surgery patient). It can also be configured to detect the extent of kidney damage if it has already occurred. The device can also be used to monitor the response to treatment / therapeutic interventions (e.g., renal replacement therapy, fluid resuscitation).

[0202] Alternative Embodiments

[0203] Embodiments of the present technology can also report patient movement in the detection or diagnosis of seizure disorders. In this embodiment, pressure fluctuations can trigger an EEG or recording device to allow monitoring of intense periods during suspected seizure episodes. Additionally or alternatively, pressure, acoustic, or other sensors can be used to detect bowel activity, including peristalsis, patient movement, seizure activity, patient shivering, cough frequency, cough severity, sleep duration, sleep quality, sound detection, and patient compliance (movement or lack thereof) to alert medical personnel that the patient is not moving and should be turned. This movement-related information can be relayed to hypothermia devices, drug delivery devices, or other devices that control or mitigate seizure activity, shivering, and / or coughing.

[0204] In some embodiments, the 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 address or resolve the water droplets. Particularly in hypothermic environments, moisture in the air lumen can condense and form obstructive water droplets. Water droplets in an air-filled lumen (or air bubbles in a water-filled lumen) can disrupt or complicate the pressure signal due to the surface tension of the water. Therefore, the pressure transmission 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 the length of the lumen) that wick moisture away from the lumen to maintain a continuous, uninterrupted air channel. In some embodiments, a hygroscopic composition (e.g., silica gel) can be used along the air insufflation line or within the air insufflation lumen itself to trap water or humidity. In some embodiments, the hygroscopic composition can be included within the catheter, eliminating the need to maintain the air insufflation circuit to replace this material.

[0205] In some embodiments of the disclosed technology, air can be intermittently (and automatically) injected and extracted from the pressure-sensing balloon to ensure that the balloon remains optimally primed and constant, as described in more detail above. Air evacuation can also help remove and capture moisture from the air line if the lumen is equipped with wicking fabric or a hydrophilic coating. In the example of a liquid-filled lumen, a hydrophilic fabric or coating on the inside of the pressure lumen offers a similar benefit by allowing the lumen to handle air bubbles, which can disrupt the signal. The hydrophilic coating on the catheter lumen reduces the surface tension at the air-water interface.

[0206] Additionally, custom extrusions and lumen shapes can be used to prevent blockages in the case of lumens filled with liquid and / or air. In some embodiments of the present technology, for example, a Foley-type catheter can have a lumen with a star-shaped cross-section. Such lumens generally avoid blockages caused by water droplets because the droplets tend to cling to themselves and be pushed away from the hydrophobic walls. This behavior tends to leave the cross-sectional space unfilled, leaving air channels around the droplets open and able to transmit to the sensor. The same principle applies to air bubbles in a hydrophilic star-shaped water lumen. In this case, the hydrophilic liquid clings to the walls, creating a continuous column of water that excludes the bubbles and extends to the center of the lumen. The same is true for hydrophobic liquids in hydrophobic lumens. In some embodiments, the catheter includes an air channel and a sensor integrated within the catheter itself or within the fluid lumen, which can transmit pressure back to the sensor.

[0207] The drainage tube may be a multi-lumen tube for housing a urinary drainage line, a pressure lumen, and thermocouple wiring, with one end connected to the barb and the other end connected to the control unit.

[0208] The Foley catheter can be used to push out BaSO4 and can be fitted with a radiopaque marker to allow fluoroscopic observation.

[0209] The thermistor at the tip of the catheter can be fixed in place using multiple extrusion profiles and assembly techniques.

[0210] In some embodiments, the sensing Foley catheter may include a blood pressure sensing element, which may take any of several forms. In one embodiment, the blood pressure sensing element includes a pressure delivery balloon (either a separate dedicated balloon or a balloon in fluid communication with a device retention balloon or a pressure sensing balloon) that can be optically analyzed as it is inflated to determine at what pressure blood vessels in the bladder or urethra branch and blood flow ceases. In this manner, the perfusion pressure of tissue adjacent to the pressure delivery balloon can be measured, which reflects both systemic blood pressure and vascular resistance. The perfusion pressure device of this embodiment can be used for early detection or monitoring of various acute or emergency medical conditions, such as sepsis, shock, and hemorrhage, and may be particularly advantageous in detecting these conditions early. When predicting sepsis, embodiments of the present invention may be able to receive white blood cell count information to better predict sepsis.

[0211] Other modalities can also be used to detect when tissue has blanched or become ischemic, with a common methodological aspect being intermittent inflation within a lumen, cavity, or bodily tissue to constrict the vasculature. Embodiments of this device and associated methods can also be used to detect perfusion pressure in other parts of the body through intermittent inflation members and optical detection of blood flow or presence.

[0212] Tissue perfusion information may be provided by sensors placed on the catheter shaft so that they contact the urethral wall when the catheter is in place. These sensing techniques may include microdialysis, pyruvate, lactate, pO2, pCO2, pH, perfusion index, near-infrared spectroscopy, laser Doppler flowmetry, urethral capnography, and cross-polarized spectroscopy. These tests can also be performed on the urine and the bladder wall itself to measure tissue perfusion.

[0213] Another example sensing Foley catheter system includes a cleaning mechanism according to one embodiment that includes a positive airflow device and / or port near the beginning of the drainage line. The positive airflow device forces urine into the drainage line, promoting drainage. The positive airflow device may include a one-way valve at the tip of the urinary catheter that allows urine to flow only toward the urine collection device and prevents air from entering the catheter.

[0214] In some embodiments, the urine cleaning mechanism comprises a coating on the inside of the urinary drainage tube to reduce surface tension and promote drainage, hi one aspect, the coating is a hydrophobic polymer, including but not limited to PTFE or FEP.

[0215] Relative cardiac output and relative tidal volume can also be calculated based on the displacement of the pressure sensor and / or force meter. By sampling at a sufficient frequency (e.g., 1 Hz or higher), it is possible to quantify the relative amplitude of respiratory excursions during catheter placement. Larger excursions generally correlate with heavier breathing or, if the baseline is fluctuating upward, with higher peritoneal pressure. By using faster sampling rates (e.g., 5 Hz or higher), even small peaks on the oscillatory respiratory wave due to the pumping action of the heart can be tracked, and the amplitude of this wave can be used to measure relative cardiac output in the setting of a relatively constant peritoneal pressure, and absolute cardiac output and / or cardiac output in the setting of a known, stable peritoneal pressure.

[0216] The intra-abdominal or bladder pressure sensed by one embodiment of the disclosed technology can also be used to sense a patient's level of movement (which can vary, for example, from substantially no movement to high levels of movement) and report the level of movement to a healthcare provider. The short occurrence of peaks and valleys in bladder pressure activity can serve as a surrogate for movement, providing a strong indicator that the bladder pressure profile is using the patient's abdominal muscles, for example, to sit up or get out of bed. This embodiment is particularly beneficial for patients at risk of falling. In this case, healthcare professionals can be notified that the patient is sitting up and can respond accordingly. Alternatively, the device can be used to report patient inactivity and / or a lack of patient movement.

[0217] The pulse oximetry element can measure blood oxygen concentration or saturation and can be positioned anywhere along the urethral length of the catheter. In some embodiments, one or more sensors are positioned within the tubing of the device to ensure close proximity to the urethral mucosa. This technique allows healthcare professionals to decompress the bladder with a urethral catheter and reproducibly and accurately acquire pulse oximetry data. The pulse oximetry power source may be integrated into the urine collection container or the catheter itself. In some embodiments, the pulse oximeter is reusable and the catheter interface is disposable. In this configuration, the pulse oximeter is reversibly attached to a disposable catheter and removed when oxygen measurements are no longer desired. Sensing Foley catheter embodiments may include an optically transparent or sufficiently transparent channel for the oximetry signal, such as a fiber optic cable, a transparent window, and an interface for a reusable oximeter. This urethral pulse oximetry method and device may be used in combination with any of the other embodiments detailed herein or may be a standalone device.

[0218] To prevent infection, an antimicrobial coating or material impregnated with an antimicrobial compound may be used on the sensing Foley catheter. Examples of antimicrobial coatings / materials include silver, silver citrate, parylene, or any other suitable material.

[0219] Pulmonary blood volume fluctuations can also be measured with a Foley catheter system to help assess the presence or risk of heart failure. Decreased left ventricular function can lead to increased pulmonary blood volume (PBV) and decreased pulmonary blood volume fluctuations. PBV fluctuations are defined as the change in PBV over time during the cardiac cycle. PBV can be measured as the product of cardiac output and pulmonary transit time (PTT). Cardiac output can be measured as the product of stroke volume and heart rate, with stroke volume being the area under the flow-time curve during one cardiac cycle. Pulse transit time can be obtained by observing the delay between the QRS complex of the electrocardiogram and the appearance of a signal in the bladder. ECG signals can be obtained from separate ECG leads, leads incorporated into the Foley catheter, leads incorporated into the catheter insertion kit, or other sources. ECG leads can also be read from anywhere in the urine. Using two leads allows for more accurate measurement of pulse transit time.

[0220] After myocardial infarction, cardiac output, ejection fraction, and PBV variability are reduced, with PBV variability being the most significant change. Therefore, measuring PBV variability and identifying a decrease in PBV variability can be a strong indication of heart failure or the risk of heart failure.

[0221] Data collected by the Foley catheter sensing system is stored in a database and can be used for trend analysis, etc. The data can include clinical data and / or device data. For example, data can be collected from multiple patients, aggregated anonymously, and used to better treat, monitor, or predict future patient behavior. For example, data collected over time regarding heart rate, respiratory rate, temperature, infections, etc. can be aggregated and analyzed by the control unit to identify trends, such as the relationship between various parameters and outcomes. For example, certain trends in temperature, alone or in combination with other parameters, may be predictive of infection, the development of sepsis, ARDS, and / or AKI. Figure 31 shows a well-known example, but it is possible that other, currently unknown, trends may emerge from the aggregated patient data.

[0222] Data collected by the sensing Foley catheter system may be integrated with a lifetime electronic health record (EHR), electronic medical record (EMR), and / or other systems. Data collected by the sensing Foley catheter system's controls may interface directly or indirectly with the EMR / EHR system. Data such as patient demographics and medical history data from the EMR / EHR may also be integrated with the sensing Foley catheter system.

[0223] Data Processing System Example

[0224] FIG. 33 is a block diagram illustrating a data processing system that can be used in any embodiment of the present invention. For example, system 3300 may be used as part of a controller, as illustrated in some embodiments herein. Note that while FIG. 33 illustrates various components of a computer system, it is not intended to represent the particular architecture or manner of interconnecting the components; such details are not relevant 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 perhaps more components may also be used in conjunction with the present invention.

[0225] As shown in Figure 33, computer system 3300, which is one form of data processing system, includes a bus or interconnect 3302 coupled to one or more microprocessors 3303 and ROM 3307, volatile RAM 3305, and non-volatile memory 3306. Microprocessor 3303 is coupled to cache memory 3304. Bus 3302 interconnects these various components and also interconnects these components 3303, 3307, 3305, and 3306 to a display controller and display device 3308, and input / output (I / O) devices 3310, which may be a mouse, keyboard, modem, network interface, printer, and other devices known in the art.

[0226] Input / output devices 3310 are typically coupled to the system via an input / output controller 3309. Volatile RAM 3305 is typically implemented as dynamic RAM (DRAM), which requires continuous power to refresh or maintain data in memory. Non-volatile memory 3306 is typically a type of storage device that retains data even when power is turned off, such as a magnetic hard disk, magneto-optical drive, optical drive, or DVD-RAM. Non-volatile memory is typically random access memory, although this is not required.

[0227] While FIG. 33 illustrates an embodiment in which the non-volatile memory is a local device directly coupled to the remaining components in the data processing system, the present invention may also utilize non-volatile memory that is remote from the system; for example, a network storage device coupled to the data processing system via a network interface, such as a modem or Ethernet interface. Bus 3302 may include one or more buses connected to each other through various bridges, controllers, and / or adapters, as is known in the art. In one embodiment, I / O controller 3309 includes a Universal Serial Bus (USB) adapter for controlling USB peripherals. Alternatively, I / O controller 3309 may include an IEEE-1394 adapter, also known as a FireWire adapter, for controlling FireWire devices.

[0228] Some portions of the detailed descriptions set forth above have been presented in terms of algorithms and symbolic representations of operations on data bits within a computer memory. These algorithmic descriptions and representations are the means used by those skilled in the data processing arts to most effectively convey the substance of their work to others skilled in the art. An algorithm, as used herein, is generally conceived to be a self-consistent sequence of operations leading to a desired result. The operations are those requiring physical manipulations of physical quantities.

[0229] It should be borne in mind, however, that all of these and similar terms are to be associated with the appropriate physical quantities and are merely convenient labels applied to these quantities. As is clear from the above discussion, unless otherwise specifically stated, throughout this specification, discussions utilizing such terms as set forth in the claims will be understood to refer to the acts and processes of a computer system or similar electronic computing device that manipulate and transform data represented as physical (electronic) quantities in the computer system's registers and memory into other data similarly represented as physical quantities in the computer system's memory or registers or other such information storage, transmission, or display device.

[0230] The illustrated techniques may be implemented using code and data stored and executed on one or more electronic devices that may store and communicate (internally and / or with other electronic devices over a network) the code and data using computer-readable media, such as non-transitory computer-readable storage media (e.g., magnetic disks, optical disks, random access memory, read-only memory, flash memory devices, phase-change memory) and transient computer-readable transmission media (e.g., electrical, optical, acoustical or other forms of propagated signals—carrier waves, infrared signals, digital signals, etc.).

[0231] The processes or methods depicted in the preceding figures may be performed by processing logic comprised of hardware (e.g., circuitry, dedicated logic, etc.), firmware, software (e.g., embodied on a non-transitory computer-readable medium), or a combination of both. While the processes or methods are described above in terms of several sequential operations, it should be understood that some of the described operations may be performed in a different order. Furthermore, some operations may be performed in parallel rather than sequentially.

[0232] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the medical arts. Although specific methods, devices, and materials are described in this application, any methods and materials similar or equivalent to those described herein can be used in the practice of the present invention. While embodiments of the present invention have been described with certain details and figures, such figures are for clarity of understanding only and are not intended to be limiting. While various terms are used herein to convey an understanding of the present invention, it will be understood that the meaning of these various terms extends to their common linguistic or grammatical variations. Furthermore, while certain theoretical considerations have been advanced to provide an understanding of the technology, the appended claims of the present invention are not intended to be bound by such theories. Furthermore, any one or more features of any embodiment of the present invention can be combined with any one or more other features of any other embodiment of the present invention without departing from the scope of the present invention. Furthermore, it should be understood that the present invention is not limited to the embodiments shown for illustrative purposes, but is defined solely by a fair reading of the claims appended to this patent application, including the full range of equivalents to which each element is entitled.

[0233] Some embodiments of the sensing Foley catheter system include the use of ultraviolet light, or light of an appropriate wavelength, to sterilize the collection chamber itself or other components of the system. The ultraviolet light source may project ultraviolet light through the wall of the collection chamber, or alternatively, the ultraviolet light source may be located inside the collection chamber. The ultraviolet light source may be used to sterilize the collection chamber when it is empty, full, or partially full. The ultraviolet light source may be used to sterilize urine as it enters the collection chamber. UV sterilization may be continuous or intermittent. The ultraviolet light source may be located anywhere in the sensing Foley catheter system. UV light, or other wavelengths of light, may be used within the bladder.

[0234] Spectroscopy - Spectrophotometer

[0235] Some embodiments of the Foley catheter system for detection include using light wavelengths ranging from about 520 nm to about 650 nm to distinguish between bacteria, red blood cells, and / or plasma / white blood cells. See the area inside the ellipse in Figure 34.

[0236] Some embodiments of the Foley catheter system for detection include combining a spectrophotometer to identify white blood cells and bacteria in combination with identifying a decrease in pO2 and / or an increase in CO2 to identify infection.

[0237] Some embodiments of the Foley catheter system include a controller that filters urine volume data to compensate for an increase in urine volume immediately following administration of a diuretic. Urine volume typically increases immediately following administration of a diuretic. However, under certain circumstances, it may be beneficial to substantially ignore data on the increase in urine volume associated with diuretic administration. The controller of the Foley catheter system can automatically ignore urine volume data associated with diuretic administration by identifying the shape of the urine volume curve associated with diuretic administration and subtracting and / or ignoring data associated with this increase. Identifying the shape of the curve can be done based on the slope, length of increase, amplitude, shape, etc. Subtracting urine volume data associated with diuretics can be useful in determining or predicting the onset of AKI. See FIG. 35. For example, the controller can recognize a diuretic-induced condition when urine volume increases by more than approximately 2,000 ml / hour (peak).

[0238] An increase in urine output due to the administration of a diuretic can be distinguished from an increase in urine output due to obstruction, such as clamping, of a urinary drainage tube and / or Foley catheter. When the drainage lumen is clamped, the urine output 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 output immediately prior to the administration of the diuretic is very low, but likely greater than zero, e.g., greater than about 5 ml / hour. Additionally, when the drainage lumen is clamped, the increase in urine output after the drainage lumen is released occurs over a relatively short period of time, e.g., from about 30 seconds to about 5 minutes. In contrast, when a diuretic is administered, the increase in urine output lasts for a longer period of time, e.g., from about 30 minutes to about 2 hours. Additionally, when the drainage lumen is clamped, the urine output after the drainage lumen is released is likely to be less than about 1000 ml. In contrast, in a situation where a diuretic is administered, the post-administration urine volume is likely to be greater than about 1000 ml. Any or all of these factors may be used by the controller to analyze the urine volume curve over time, determine when a diuretic is administered, and subtract the increase in urine volume due to the diuretic from the urine volume presented to the user.

[0239] In this manner, the controller may automatically determine when to administer a diuretic. Alternatively, the user interface of the controller may include a button or other user input device (e.g., touch screen, voice control) that indicates that a diuretic has been administered. The controller would then look for an increase in urine volume and subtract the increase in urine volume due to the diuretic from the urine volume data presented to the user.

[0240] Some embodiments of the sensing Foley catheter system include a controller measuring abdominal perfusion pressure (APP). APP is defined as the difference between mean arterial pressure and intraperitoneal pressure (IAP). Mean arterial pressure can be measured by conventional methods, and APP can be measured in combination with the controller's measurement of IAP. The controller can further automatically vary the infusion of fluids and / or vasopressors / vasopressors to increase or decrease blood pressure.

[0241] The embodiment shown in Figure 36 also prevents wetting of the vent / filter. This embodiment includes a vent tube 3602 having a lumen that connects to the drainage lumen 3604 near the barb area 3606 and is vented to atmosphere or other air / gas / fluids via one or more filters / vents 3608 along the vent tube and / or near the other end. The filter / vent may be within the collection reservoir as shown in Figure 36, or may be separate from the collection reservoir, etc.

[0242] The vent lumen may be incorporated into the drainage lumen, either alongside or within the urinary drainage lumen. Alternatively, the vent lumen may be separate from the drainage lumen and connected to the drainage lumen near the junction of the vent tube and the drainage tube, e.g., near the barb region 3606.

[0243] Any of the embodiments herein may include physiological pressure measurement or may be used without physiological pressure measurement, for example, the system may be used with a standard Foley catheter without a thermistor or pressure lumen.

[0244] In some embodiments, pressure may be measured at the junction of the positive pressure tubing and the drainage tubing. Alternatively, pressure may be measured at the junction of the sensing Foley catheter and the drainage tubing, or at the region of the barb. Pressure can be measured at any of these locations by incorporating an additional tube or lumen that is in fluid communication at one end with the junction of the pressure tubing and the drainage tubing, or at the region of the barb, and at the other end with a pressure sensor or transducer. For example, this pressure measurement lumen may have one end (sensor side) in fluid communication with a control unit that houses a pressure sensor, and the other end (sensing side) in fluid communication with the junction of the positive pressure tubing and the drainage tubing. A pressure-sensitive membrane may be provided on the sensing side to prevent contamination of the lumen with urine.

[0245] Further detection of airlocks can allow for optimal elimination and / or prevention of airlocks. Using any of the embodiments herein, the controller can apply a slight positive or negative pressure to the urinary drainage lumen and detect the response. Because air is more compressible than urine, a sluggish response indicates the presence of an airlock, while a less sluggish response indicates less airlock. If excessive airlocks are detected, the controller can initiate airlock elimination, such as by applying negative pressure to the drainage lumen.

[0246] In some embodiments, an airlock may be detected using a flow meter(s) or flow sensor(s) integrated into the system. For example, a flow meter may be added to the vent tube and / or near or within the cassette. Low or current air flow through the vent tube may indicate an airlock in the urinary drainage line. A low vacuum may be applied to the drainage line to determine if there is flow through the vent tube; if there is still no flow, an airlock is likely present and airlock resolution may be initiated. Additionally or alternatively, a flow sensor may be located within or near the cassette. When vacuum is applied to the drainage line, no or low flow at or near the cassette may indicate an airlock. The level of flow may indicate a near-occlusion based on the compliance of the system / drainage tube. For example, an occlusion due to a clamp near the Foley catheter may result in some flow through the cassette when vacuum is applied, whereas an airlock near the cassette may result in little or no flow through the cassette when vacuum is applied.

[0247] In some embodiments, the valve may be located anywhere in the system, including in the positive pressure tubing or in the reservoir.

[0248] The vent tube may be a separate tube from the drainage tube and may be inserted into the drainage lumen or the Foley catheter. FIG. 37 illustrates an embodiment of a Foley catheter sensing system in which the vent tube is located within the urinary drainage tube. This type of embodiment has the advantage that any common drainage tube can be used. The vent tube essentially positions the vent anywhere within the drainage lumen, either within the drainage tube or within the Foley catheter. The vent tube is slidably inserted within the drainage tube and / or Foley catheter and can be moved at any time.

[0249] In the embodiment shown in FIG. 37 , the vent tube 3704 may be open at one end (the “air end” 3708) to a vent / filter 3702 in the collection reservoir (open to atmospheric pressure) and at the other end (the “urine end” 3710) within the urinary drainage lumen 3706. While the vent tube is shown here terminating within a barb at the base of the Foley catheter, the vent tube can terminate anywhere within the urinary drainage lumen, including within the drainage tube or anywhere within the Foley catheter. The vent tube can remain in one place or move within the system to maximize urine drainage and minimize airlock and bladder damage due to negative pressure within the bladder.

[0250] FIG. 38 illustrates an alternative Foley catheter sensing system in which a vent tube 3802 has a vent / filter 3804 at the "urine end" of the tube and is open to atmosphere at the "air end" 3806 of the tube. Alternatively, a filter / vent may be provided 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 built into the collection container. Again, the vent tube can be used with any urinary drainage tube, including standard urinary drainage tubes.

[0251] FIG. 39 shows an embodiment similar to that shown in FIG. 38 with the addition of a positive pressure tube 3902.

[0252] In any of the embodiments including any type of airlock elimination mechanism, airlock elimination may be performed continuously, periodically (either at regular intervals or on demand), on demand, or when an airlock condition is detected. The airlock elimination mechanism prevents or mitigates airlocks. For example, the airlock elimination mechanism may mitigate airlocks to defuse the airlock at least every 60 minutes. Alternatively, the airlock may be defuse at least every 45 minutes. Alternatively, the airlock may be defuse at least every 30 minutes. Alternatively, the airlock may be defuse at least every 20 minutes. Alternatively, the airlock may be defuse at least every 10 minutes. Alternatively, the airlock may be defuse at least every 5 minutes. Alternatively, the airlock may be defuse at least every minute.

[0253] In any of the embodiments that include a vent or filter or vent tube as part of the barb region or drainage tube, gas / air introduced into the drainage lumen via the vent / filter / vent tube may cause discontinuous or interrupted drainage of fluid (i.e., urine), i.e., the drainage lumen may alternate between liquid (i.e., urine) and gas flow.

[0254] In any of the embodiments involving real-time urine volume measurements, real-time may mean that the reported urine volume measurements are accurate to within about 1 minute. Alternatively, real-time may mean that the reported urine volume measurements are accurate to within about 5 minutes. Alternatively, real-time may mean that the reported urine volume measurements are accurate to within about 10 minutes. Alternatively, real-time may mean that the reported urine volume measurements are accurate to within about 20 minutes. Alternatively, real-time may mean that the reported urine volume measurements are accurate to within about 30 minutes. Alternatively, real-time may mean that the reported urine volume measurements are accurate to within about 60 minutes.

[0255] Air bubbles in urine - prevent air bubbles and / or influence on measurement.

[0256] Proteins and other components in urine can cause excessive foaming in the drainage lumen and / or urine in the collection container, which can lead to problems such as wetting of the vent / filter(s), urine entering the overflow area of the collection container, inaccurate measurements, etc. Some embodiments of the sensing Foley catheter system incorporate an anti-bubble mechanism.

[0257] In some embodiments, such as those incorporating positive pressure tubing, the pressure within the urinary drainage can be precisely controlled. It is also possible to occasionally apply a slight positive pressure within the drainage system (i.e., the drainage lumen and / or collection chamber) to collapse or prevent air bubbles from forming.

[0258] Surfactants of suitable materials such as silicone, simethicone, etc. may be added to the system. For example, slow-dissolving silicone capsules may be added to the collection reservoir. Alternatively, a surfactant may be applied to the inside of the drainage lumen and / or the inside of the collection container.

[0259] Alternatively, or in addition, a flat mesh section can be inserted anywhere in the system, for example, at the junction of the drainage tube and collection container.

[0260] In some embodiments, the cassette and / or the drainage lumen can be vibrated continuously or intermittently to break up air bubbles.

[0261] 40A-40C illustrate embodiments incorporating a floating or non-floating plate to compress or break up air bubbles at or near the surface of the urine in the collection container. The plate 4002 may simply float on the surface and passively rise and fall depending on the amount of urine 4004 in the container, or the plate may be actively raised and lowered. The plate may be fixed in place. The plate may be porous or solid. In embodiments where the plate is above the liquid surface, the plate may also be used to measure urine volume. The position of the plate may be determined by techniques such as ultrasound, visual means (e.g., camera), or laser. The volume of fluid in the collection container may be measured directly from the fluid level, which is determined by the position of the plate.

[0262] The interior of the cassette may be rectangular or may have other shapes. For example, the sides of the interior of the cassette may taper inward toward the bottom to provide a larger urine surface relative to the volume of urine in the cassette. This allows for more accurate measurement of smaller urine volumes.

[0263] Some embodiments may include a volumetric septum at a set volume mark, such as 50 ml. This volumetric septum may be similar to septum 2002 shown in FIG. 20, except that it is at a predetermined volume position. When the top of the urine volume in the cassette is at or near the volumetric septum, the ultrasound signal is stronger than at other times. For example, the volumetric septum can be positioned so that when the top of the urine volume is approximately 50 ml (or other set volume), the top of the urine volume is at or near the volumetric septum. The ultrasound signal is strongest when the two surfaces (urine and volumetric septum) are close to or touching each other.

[0264] Some embodiments may include a waveguide to help account for the tilt of the reservoir. For example, an ultrasonic signal may be guided into a cylinder with flat or curved sides, directing the ultrasonic waves toward and reflecting from the surface of the fluid in the reservoir. The waveguide may extend all or part of the way into the reservoir. The waveguide may extend between the ultrasonic transducer / sensor and the surface of the fluid.

[0265] In some embodiments, the ultrasonic transducer / sensor may be flat, and in some embodiments, the surface of the ultrasonic transducer / sensor may be curved, for example, a convex curve, which helps spread the ultrasonic signal over more angles and helps ensure that some of those angles are reflected from the liquid surface in the reservoir.

[0266] Some embodiments include a controller that uses an accelerometer to measure the tilt of the reservoir and then uses the angle of tilt to calculate the volume of fluid remaining in the reservoir (i.e., in the lower corners of the reservoir) after fluid has been emptied from the reservoir. This calculated volume remaining in the reservoir can be added to the calculation of total urine volume to improve accuracy.

[0267] 41A shows a sensing Foley catheter system according to one embodiment that includes valves at both the drainage port 4102 and the inlet port 4104 where the drainage tube connects to the collection reservoir. This allows the controller to periodically pressurize the collection reservoir to help reduce air bubbles and / or drain the collection reservoir. The inlet port valve also allows the controller to stop urine flow to the collection reservoir while it is being emptied, resulting in more accurate urine volume measurements.

[0268] In embodiments where the valves are active rather than passive ("active" meaning controlled by the controller rather than by differential pressure across the valve), the controller can calibrate the valve mechanism for each disposable unit to account for differences in tubing thickness, hardness, diameter, material, etc. For example, a motor can be used to open and close an active valve, such as the valves disclosed herein. A light gate can be used to assess whether the valve is closed on tubing. The controller can count the number of rotational steps, etc., required to close a particular tubing on a particular disposable. This count can be used in subsequent closures of the same disposable. This calibration can occur when the disposable is first attached to the controller. Thereafter, calibrations can be performed on the same disposable periodically or as needed.

[0269] For example, when a new disposable, identified by an RFID tag or the like, is used, the controller rotates the valve motor one revolution, and a light gate detects maximum closure of the tubing. The controller counts the number of revolution steps until the tubing is fully closed. This number of motor revolution steps may be assumed to close the tubing of the disposable until the next calibration of the valve of that particular disposable.

[0270] 41B illustrates a collection container according to an embodiment in which the urine overflow path 4106 is longer and / or more complex and / or more tortuous and / or narrowed. This configuration makes it difficult for air bubbles to flow into the overflow path, resulting in an inaccurate measurement of urine volume. The overflow path may include one or more path angles greater than 45 degrees.

[0271] FIG. 41C illustrates a collection container according to one embodiment in which the fluid path (indicated by the dashed arrows) between the urine in the reservoir and the cassette pump interface 1148 is long and tortuous to prevent wetting of the interface 1148. The cassette pump interface 1148 may include a gas-permeable, liquid-impermeable filter. The length of the fluid path can be approximately 6-12 cm. Alternatively, the length of the fluid path can be approximately 3-6 cm. Alternatively, the length of the fluid path can be greater than approximately 12 cm. Alternatively, the length of the fluid path can be approximately 3-6 cm. Alternatively, the length of the fluid path can be greater than approximately 20 cm.

[0272] 41E illustrates an alternative collection container in which the fluid path (shown in dashed lines) between the urine in the reservoir and the cassette pump interface 1148 is long and tortuous to prevent wetting of the interface 1148. The tortuous path may include coiled or bundled small diameter tubing 4108 as all or part of the fluid path. Preferably, the tortuous path is three-dimensionally tortuous.

[0273] Figure 41E shows an alternative collection container in which the fluid path (shown in dashed lines) between the urine in the reservoir and the cassette pump interface 1148 is long and tortuous to prevent wetting of the interface 1148. This embodiment includes both small diameter tubing 4108 and a tortuous path molded into the cassette. The tortuous path may be partially molded, partially tubing, all tubing, or all molded.

[0274] The inner diameter of small diameter tubing 4108 may be about 1.8-2.0 mm. In some embodiments, the inner diameter may be about 1.6-1.8 mm. In some embodiments, the inner diameter may be about 1.4-1.6 mm. In some embodiments, the inner diameter may be about 1.2-1.4 mm. In some embodiments, the inner diameter may be about 1.0-1.2 mm. In some embodiments, the inner diameter may be about 0.8-1.0 mm. In some embodiments, the inner diameter may be about 0.5-0.8 mm. In some embodiments, the inner diameter may be about 0.2-5 mm. In some embodiments, the inner diameter may be less than about 4 mm. In some embodiments, the inner diameter may be less than about 3 mm. In some embodiments, the inner diameter may be less than about 2 mm.

[0275] In some embodiments, the drainage tube includes a small lumen diameter. For example, in some embodiments, the lumen diameter is about 2 mm. In some embodiments, the lumen diameter is about 1 mm. In some embodiments, the lumen diameter is about 3 mm. In some embodiments, the lumen diameter is less than about 2 mm. In some embodiments, the lumen diameter is less than about 1 mm. In some embodiments, the lumen diameter is less than about 3 mm.

[0276] In some embodiments, the expelled urine can be used to "clean" any air bubbles in the drainage tube or collection reservoir. Urine can be returned to the drainage tube, increasing the volume within the drainage tube and helping to "clean" any air bubbles within the tube and / or reservoir. The controller accounts for recycled urine when calculating urine volume.

[0277] In some embodiments, pressurized air may be introduced into the drainage tube and / or collection container. The forced air pops and / or compresses air bubbles and also forces the urine against the surfaces of the system, reducing bubble formation. The cross-sectional area of the drainage tube may decrease, remain the same, or increase as the drainage tube transitions to the flattened section.

[0278] Leveling

[0279] In embodiments that use ultrasound to measure urine volume in a collection container, it is important that the ultrasound have a surface (i.e., the surface of the urine volume) that is at an angle of approximately 90 degrees from the ultrasound sensor. If the device is tilted even a few degrees, the ultrasound sensor may not be able to detect the surface of the urine, resulting in an inaccurate urine volume measurement. To compensate for this, the collection container or base / control unit may be attached to the bed via a self-leveling attachment, such as an attachment on rollers that allows gravity to automatically level the base when the attachment is attached.

[0280] In some embodiments, slight angles within the system are addressed by creating a "rough" surface on the urine volume within the collection reservoir. A "rough" surface creates multiple angles for ultrasound reflection, some of which are approximately 90 degrees from the ultrasound sensor / transducer. Roughness can be created by vibrating the collection reservoir and / or urine by using air or other gases to bubble the urine. Vibration can be achieved mechanically, ultrasonically, or otherwise. Floating plates that float on the urine surface can have rough, concave, or convex undersides. Floating beads can remain in the reservoir as urine is drained because their diameter is too large to exit the reservoir. Mechanisms such as a mesh, constriction, or small-diameter opening can be used to prevent beads from entering the overflow area. Additionally, as described above, angled septa or cassettes (i.e., urine collection chambers) with angled or tapered walls can also be used to accurately measure urine volume.

[0281] Priming the pressure balloon

[0282] A very small amount of air or fluid may be required for priming to regulate the pressure of the pressure balloon and provide optimal pressure sensing measurements. For this reason, an air / gas / fluid restrictor may be utilized between the priming fluid and the pressure balloon. The restrictor allows the priming pump to operate with less air, resulting in more accurate priming of the pressure balloon. The restrictor may include a foam insert, a narrowing of the fluid lumen, or any other suitable restrictor.

[0283] General Improvements

[0284] In some embodiments, sensors on the bed, on the patient, in the sensing Foley catheter system, or elsewhere detect whether the patient is supine. If the patient is not supine, the measured pressure in the bladder may increase, adversely affecting the data analyzed by the controller. As a result, the controller may ignore pressure data collected while the patient is not supine or may stop collecting pressure data during this time. Alternatively, the pressure measurement itself may be used to detect when the patient is not supine. A sudden increase in pressure or an increase above a certain threshold may indicate the patient is sitting up, moving, coughing, etc. Different pressure profiles may indicate different events. Patient rolling to prevent bedsores may be tracked in this manner.

[0285] In some embodiments, electrocardiogram measurements obtained through leads attached to the sensing Foley catheter system or obtained independently are used to synchronize the heart rate measured via the intravesical heart rate with the electrocardiogram.

[0286] In some embodiments, the bed angle can be used by the controller as an input parameter to calculations 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, measuring IAP at different bed angles can provide additional information about the patient's health status. Lowering the head height can also reduce IAP, temporarily stabilizing patients with high IAP.

[0287] In some embodiments, the sensing Foley catheter will have at least one pressure sensor or lumen in fluid communication with an external pressure sensor. This pressure sensor can sense pressure within the lumen at high speed, i.e., high frequency (ideally faster than 1 Hz), and monitor physiological signals within the lumen. In some embodiments, the pressure lumen can be manually or automatically pressurized and / or depressurized while pressure is continuously or intermittently monitored. In embodiments where the pressure lumen includes a pressure balloon, the balloon can be inflated and / or deflated while the body's pressure on the pressure balloon is monitored. The pressure lumen can transmit pressure waves from the body cavity, one of which is a cardiac pulse caused by blood inflow, and can be transmitted to hollow organs and / or surrounding tissues. Pulsatile pressure due to cardiac pulsation and / or respiratory excitation can be used to measure pulmonary and cardiovascular pressure. Additionally, the pressure in the pressure lumen / balloon can be increased above a threshold (e.g., 100 mmHg (approximately 13.33 kPa)) and then slowly decreased within the detection range to determine the onset and disappearance of the pressure pulse, and / or the relative increase or decrease in pressure pulse size. The onset and disappearance of pressure pulses detected by the pressure sensor, as well as their relative increase or decrease, can be correlated with blood pressure, perfusion pressure, mean arterial pressure, cardiac output, cardiac output variation, respiratory effort, pulmonary artery pressure transmission, and other pulmonary, gastrointestinal, renal, or cardiovascular parameters. This process is similar to a blood pressure cuff, where the pressure is increased above the blood pressure and then slowly decreased until a blood pressure waveform (heartbeat) appears or disappears.

[0288] Figure 42 shows the pressure waveform and its disappearance as the pressure balloon is inflated. Note that the cardiac pulsation is reduced and / or disappeared when it is greater than the mean arterial pressure. If there is enough data to correlate the degree of disappearance at the relative pressure points to the mean arterial pressure, it is possible to derive the mean arterial pressure from this relative pressure waveform. This can be used for pressures that can be sensed within body cavities, such as pulmonary pressure.

[0289] In some embodiments, the pressure sensor / lumen is a capsule, or balloon, or reservoir that can be slowly inflated or filled while pressure is monitored using an external transducer. In some embodiments, the pressure sensor is associated with a urinary catheter, such as a Foley catheter. Alternatively, the pressure sensor can be associated with a nasogastric, orogastric, or rectal tube. In further embodiments, the pressure sensor device and associated pressure intensifier may be fully implantable. In tissue perfusion embodiments, a pressure detector can be inflated within the urethra or against the luminal surface, and pulse oximetry can be performed to detect blanch and / or perfusion of the luminal tissue at each pressure to measure tissue perfusion pressure.

[0290] In some embodiments, the catheter can synergistically use multiple measurement parameters to improve the quality of data analysis. In one embodiment, the catheter incorporates a sensor for capturing an ECG signal internally, such as from the urethra or bladder, or externally, such as via sensors placed on the legs or lower back. This signal can be used to synchronize other measurement parameters (e.g., cardiac output) synchronized with the cardiac cycle with the electrical signal and remove noise by taking the mean or median signal of many individual samples. In another example, a respiratory signal can be used to guide which cardiac pressure signal should be used in cardiac output variability analysis by waiting for a model waveform to appear before performing the analysis.

[0291] Figure 43 illustrates how cardiogenic signals (such as intrabladder pressure fluctuations due to the nearby abdominal aortic pulse) can be synchronized to obtain a clean signal for analysis. When an electrocardiogram (ECG) is acquired synchronously with other related cardiac signals, individual samples can be synchronized using, for example, the R wave of the ECG. In this illustration, multiple pressure samples are acquired and aligned using the R wave of the ECG to create a superimposed signal. The median value of all pressure samples taken at the same time during the cardiac cycle is then taken to calculate the intermediate signal. Average values can also be used. In this way, any excessively high values due to noise in one sample are offset by the correspondingly low values in another sample, thereby filtering out random noise. The more data points available, the stronger the underlying signal becomes for analysis. For example, in the pressure signal shown, the relative cardiac output can be derived from the signal's peak-to-peak amplitude.

[0292] Figure 44 illustrates a method for using respiratory pressure signals to inform cardiac pressure signal analysis to measure cardiac output variability (SVV). This method is particularly useful in non-ventilated patients, i.e., patients not on a ventilator. Existing cardiac output measurement techniques, such as thermodilution and pulse contour analysis, are limited in their ability to measure cardiac output variability (variation in cardiac output between inspiration and expiration) due to their inability to observe the respiratory cycle. Using intraluminal pressure signals, such as those from an intravesical Foley catheter, as described herein, is advantageous in that it simultaneously captures respiratory and cardiac signals (as well as slow-moving intra-abdominal pressure signals). In this way, the device can discriminately select which respiratory cycles to use in cardiac output variability analysis because certain characteristics (e.g., respiratory rate and magnitude) are more suitable for appropriate analysis. This figure shows a sample of a pressure signal acquired from the bladder. In the raw pressure signal at the top, large fluctuations are due to respiration and are selected for analysis based on, for example, wave width, amplitude, and peak value. Other characteristics not shown can also be used to define suitable waves, including slope, area under the curve, shape, frequency, pattern, or repeatability. A curve amplitude filter can also be used, using curves with amplitudes greater than a predetermined value and not using curves below the same or another predetermined value in calculating SVV. The figure below shows the same signal after passing it through a high-pass filter and a low-pass filter. The high-pass filter retains the underlying cardiac signal (dashed line), while the low-pass filter retains the underlying respiratory signal (solid line). In this example, the difference in cardiac signal strength between the peaks and valleys of the respiratory signal (e.g., peak-to-peak value) can be used to calculate cardiac output variation.

[0293] 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 tidal volume, spirometry, respiratory flow parameters, data collected via spirometry, expiratory effort, inspiratory effort, etc. Any of these parameters may be used to assist in the calculation of cardiac output variation and / or other cardiac parameters.

[0294] The filter used to determine the pressure peak to use in the SVV calculation may be based on any of the pressure curve parameters disclosed herein. In addition, the SVV calculation itself may determine which pressure curve peak to use in the calculation. For example, SVV typically falls within a range of approximately 10%. The systems disclosed herein may include or exclude pressure curve data based on whether the resulting SVV calculation falls within a certain range of values, such as approximately 10%.

[0295] Additionally, the calculation of SVV can vary from patient to patient. For example, the pressure curve peak filter is based on amplitude, but the cutoff amplitude is patient-specific and can be based on the mean, mean, or other parameters of that patient's pressure curve. Alternatively, filtering can be based on multiple patients, or multiple patients within a particular category, such as a particular disease state.

[0296] The signal and / or SVV calculation may also be filtered for patient movement and / or other artifacts such as coughing, moving, sneezing, etc.

[0297] Additionally, a calculated SVV that is very low or absent may be a sign of fluid overload and may require appropriate treatment.

[0298] In some embodiments of the disclosed system, the patient may be prompted to breathe in a particular manner. For example, based on the shape of the pressure curve (peak amplitude, frequency, etc.), the system may prompt the patient to breathe deeper, breathe slower, breathe normally, etc. The resulting respiratory pressure curve may be factored into the calculation of SVV. This type of prompting may be performed by the system if the pressure curve is inappropriate for performing the SVV calculation, or for other reasons.

[0299] Figures 45A and 45B are two-view diagrams showing the base of the sealing mechanism between the cassette and the control unit. Typically, the base shown in Figures 45A and 45B connects to the cassette, and the pin shown in Figure 46 connects to the control unit. However, the reverse installation is also possible, with the pin connected to the cassette and the base connected to the control unit. The purpose of the sealing mechanism is to connect the lumen in the cassette to the lumen in the control unit when the cassette is connected to the control unit, and simultaneously seal the lumen in the cassette when the cassette is disconnected from the control unit. For example, the cassette may be temporarily disconnected from the monitor / control unit when a patient is transported to surgery or moved between rooms. While the cassette is disconnected from the control unit, it is desirable to seal the lumen to prevent contamination of the cassette lumen and to prevent urine, fluids, or gases from leaking or entering the system.

[0300] For example, lumens such as the pressure balloon lumen (such as pressure transducer interface 1026), vent lumen 1180, cassette pump interface 1148, and / or cassette pressure interface 1150 may have such connectors.

[0301] 45A and 45B show the connector base 450. The base can be made of a compressible, strong, and inert material, such as silicone or rubber. Base 450 includes a base head 4504, a base stem 4508, and a base anchor 4502, as well as a slit 4506 having a length L3. Preferably, slit 4506 is a single, linear slit, but after the base is molded, it can be slit with a sharp knife to ensure that the edges of the slit are not rounded and that a complete seal can be achieved while remaining relatively loose. When base 450 is connected to the lumen, fluid cannot flow through the slit in the base.

[0302] 46 includes a pin head 4604 and a pin stem 4602 with a lumen therethrough. The pin stem 4602 has an outer diameter D3. The pin 460 fits inside a slit 4506 in the base 450 and is so positioned to allow fluid to pass through the sealing mechanism. In some embodiments, L3 is approximately the same as D3.

[0303] 47A and 47B show an embodiment in which a pin 460 is inserted into a slit 4506 in the base 450, thereby allowing fluid to flow through the lumen of the pin and past the sealing mechanism.

[0304] Figure 48 shows the base of the sealing mechanism 450 on the back of the cassette, which is designed to fit into the opening in the control unit. The base of the sealing mechanism shown here connects to the pressure balloon lumen interface 4802, the vent lumen interface 4804, the cassette pump interface 4806, and the cassette pressure interface 4808 (for measuring IAP). Note that these types of sealing mechanisms may be used on all, some, or none of the cassette interfaces. For example, the pressure interface 4808 for measuring IAP does not need to seal when the cassette is disconnected, and a different type of connector may be used.

[0305] Figure 49 illustrates the operation of the sealing mechanism when the cassette is connected to the controller. Cassette 1022 is shown in cross section with one of the sealing mechanisms installed. Base 450 is attached to the cassette section and would be sealed if pin 460 were not provided. Pin 460 is connected to the controller (not shown) and, when cassette 1022 is snapped into place in the controller, pin 460 is inserted into a slit in base 450, allowing fluid to flow from the controller to the cassette or vice versa. The connection may include a filter, shown here as filter 4902.

[0306] Figure 50 shows the approximate dimensions of the base 450 according to one embodiment. These dimensions may vary depending on the application.

[0307] FIG. 51 illustrates some of the forces acting on the base 450 when the entire base 450 is installed into the cassette. These forces are caused by the diameter of the mounting hole versus the diameter of the stem 4508, and the thickness of the cassette wall versus the length of the stem 4508. Additionally, compressive forces may press against the base head 4504 when the cassette is attached to the controller. These forces tend to strengthen the seal of the base 450, regardless of whether a pin is inserted into the slit. That is, the forces are applied to help the slit remain either closed on itself or closed by the pin, depending on the dimensions and shape of the base. The forces push the slit inward on itself. Also, because the head 4504 has a slightly concave bottom (like a mushroom), the bottom (wider portion) tends to expand and the top (where the slit opening is) tends to compress. This is especially true if the cassette wall thickness is greater than the length of the stem 4508.

[0308] 52A and 52B illustrate an embodiment of a sealing mechanism in which the base or head or other component includes an orientation feature 5202. The orientation feature can match a similar orientation feature on or in the opening of the cassette so that the sealing mechanism is oriented to a specific location within the opening of the cassette upon assembly.

[0309] In some embodiments, multiple drainage lumens can be used to prevent airlock. The proximal and / or distal openings can be staggered. The lumens can be incorporated into single or multiple tubes, and may or may not maintain a siphon. For example, two drainage lumens, three drainage lumens, four drainage lumens, five drainage lumens, six drainage lumens, seven drainage lumens, eight drainage lumens, or more than eight drainage lumens can be used.

[0310] In any of the embodiments disclosed herein, the vent tube can be connected to a standard or non-standard Foley catheter by attaching it to the sampling port of the Foley catheter, or to a barb near the Foley catheter, or anywhere in the drainage system. See, e.g., FIG. 53.

[0311] FIG. 53 illustrates an embodiment including a venting mechanism / vent tube that can be added to any urinary drainage system that includes any suitable port, such as a sampling port 1004. In this embodiment, the venting mechanism 5300 can vent the sampling port 1004 to prevent airlocks. The venting mechanism 5300 includes a vent tube 5302 and, optionally, a valve 5304 and / or a filter 5306. The venting mechanism can also include a needle, or puncture mechanism or blunt tube 5308, that punctures or opens / accesses the sampling port 1004 and holds open a lumen in fluid communication with the drainage lumen 1012 to perform the venting function. While the sampling port is shown as part of the barb 1016 in this illustration, the sampling port may be located anywhere in the drainage system, including within the drainage line, as part of the drainage catheter, between the drainage catheter and the drainage line, or elsewhere. Alternatively, any other port or access point may be used. This embodiment may or may not use a vacuum pump. The vent tube may be rigid, flexible, or bendable. The vent mechanism may include means for suspending the vent tube above the level of the bladder, for example, 1 to 10 cm above the level of the bladder. The length of the vent tube may be just greater than 1 cm. Alternatively, the length of the vent tube may be just greater than 2 cm. Alternatively, the length of the vent tube may be just greater than 3 cm. Alternatively, the length of the vent tube may be just greater than 4 cm. Alternatively, the length of the vent tube may be just greater than 5 cm. Alternatively, the length of the vent tube may be just greater than 10 cm. The inner diameter of the vent tube may be less than about 5 mm. Alternatively, the inner diameter of the vent tube may be less than about 4 mm. Alternatively, the inner diameter of the vent tube may be less than about 3 mm. Alternatively, the inner diameter of the vent tube may be less than about 2 mm. Alternatively, the inner diameter of the vent tube may be less than about 1 mm.

[0312] While the vent tube 5302 is shown terminating in the atmosphere in this illustration, it may also be connected to a drainage bag, as shown in FIG. 11E. When a valve and vent are provided, 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 venting mechanism can be implemented in the sampling port after the initial volume of urine has been drained from the bladder. This type of venting mechanism may also be incorporated into a strap or patch used to secure the barb to the patient's leg, etc. The venting mechanism / vent tube of this embodiment may have one or more narrow diameter sections with a length, as shown in FIG. 11D. For example, a section of the vent tube 5302 may be relatively long and of a relatively small diameter to prevent urine from traveling through the vent tube and reaching the valve and / or filter.

[0313] Rather than using a puncture mechanism 5308 in conjunction with the sampling port 1004, a puncture mechanism may be used along the tubing of the catheter or drainage tubing. Alternatively, the port may be normally closed but may be configured to accept an add-on vent mechanism / vent tubing. For example, a seal mechanism-pin configuration such as that shown in FIGS. 45-52B may be used, where the base is on the catheter / drainage tubing and the pin is part of the vent mechanism / vent tubing, or vice versa. In some embodiments, the port 1004 may be provided on an add-on barb or connector piece intended to be placed between the catheter and the drainage tubing.

[0314] Any of the vent tube embodiments disclosed herein may additionally or alternatively be used to vent a drainage bag or cassette. For example, bag vent 1142 shown in FIG. 10A may incorporate any of the vent tube designs. Alternatively, for example, vent 1180 shown in FIG. 11A may incorporate any of the vent tube designs.

[0315] 54A and 54B illustrate a barb according to one embodiment, including a tube seating mechanism. Barb 5402 includes a urinary drainage tube 5404 surrounding a urinary drainage lumen 5406 and a vent tube 5408 surrounding a vent lumen 5410. The tubes 5404 and 5406 are inserted into the barb during manufacture and seat against a step 5412, thereby opening both the urinary drainage lumen and the vent lumen to a single lumen 5416 of the catheter manifold 5414, as shown in FIG. 54B.

[0316] In some embodiments, the controller controls a pressure sensor at or near the barb to determine when the pressure in the barb area is not too negative so that a vacuum can be drawn on the drainage line without causing aspiration trauma to the bladder. The pressure sensor may also be used to determine the initial positioning of the system to ensure that the pressure in the drainage line is not too positive or too negative. If the pressure in the drainage line becomes too negative, the controller can operate a valve in a urine collection reservoir or the like to temporarily stop or slow urination to prevent the pressure from becoming negative and reduce the possibility of aspiration trauma to the bladder.

[0317] In some embodiments, the bladder is periodically pressurized to assist in emptying urine from the bladder, which can be done using a retention balloon, a pressure-sensing balloon, another balloon, etc.

[0318] In some embodiments, the airlock is cleared intermittently. In some embodiments, the airlock is cleared continuously, for example, by continuously pulling a slight vacuum on the drainage line.

[0319] In some embodiments, pulse oximetry data may be collected from the patient's skin, for example, from the thigh, or other locations on the groin or leg.

[0320] In some embodiments, the controller manages the air volume and / or pressure throughout the system. For example, the controller can detect when the urine collection bag becomes over-pressurized, which can occur if the air filter (shown as 1142 in some figures) is blocked or wet, increasing the risk of the bag bursting. In this case, the controller can instruct the system to do one or more things to mitigate the problem. The controller may attempt to clean the filter by "blowing" air through it. The controller may slow or stop urine output by slowing or stopping the airlock relief pump. The controller may instruct the pump to intermittently reverse rotation to reduce pressure in the drainage bag. The controller may alert the user to change or otherwise manually correct the drainage bag problem. The controller can monitor pressure anywhere in the system to identify and potentially mitigate pressure-related issues. The controller can monitor pressure in the barbs, drainage lines, vent lines, reservoirs / cassettes, drainage bags, etc. For example, the controller may control the pressure within the cassette to assist in emptying the cassette, cleaning the filter, reducing air bubbles, and the like.

[0321] In some embodiments, acute kidney injury (AKI), or other conditions, can be detected early and, in some cases, predicted and / or prevented. For example, AKI is currently classified using the RIFLE (Risk, Injury, Failure, Renal Decline, and End-Stage Renal Disease) criteria. The RIFLE criteria include the following classifications:

[0322] [Table 1]

[0323] The embodiments of the sensing Foley catheter system disclosed herein can measure urine output, as well as intraperitoneal pressure and other parameters in real time, frequently, or continuously, so that patient health parameters can be assessed in context and over time. For example, urine output can be measured continuously, and the data can be captured, stored, and analyzed over time. Patient weight and other patient-related data can be input into the system. As a result, UO / kg / h can be easily captured, calculated, tracked, and analyzed over time. Based on the RIFLE criteria, alerts can be programmed to trigger at or before the occurrence of AKI risk, injury, and failure. Patient weight and / or other patient data can be received by the system controller via manual user input, integration with other hardware such as a scale, integration with a lifetime electronic medical record or electronic health record, wireless transmission, or other means.

[0324] Additionally, sensing Foley catheter systems may use different algorithms or refine existing algorithms to predict or identify patient conditions, for example, by considering earlier available urine output data to predict the risk of kidney damage or failure earlier than the RIFLE criteria.

[0325] As an example, referring to Figures 55A through 55E, Figure 55A is a graph showing the change in urine volume over time in hourly increments. The urine volume scale is marked with a line at 0.5 mL / kg / h. According to the RIFLE criteria, urine volume below this level for six consecutive hours indicates a risk of kidney damage. The most recent six urine volume measurements (hours 12 through 17) represent symptoms that, according to the RIFLE criteria, indicate an increased risk of kidney damage. A Foley catheter detection system can add more information beyond these data to the patient's condition. For example, looking at urine volume at hours 9, 10, and 11, we can see a decrease in urine volume at each time point. Following this decrease, a 3-hour urine volume below 0.5 mL / kg / h predicts a further 3-hour urine volume below 0.5 mL / kg / h. That is, a decrease in urine output (even greater than 0.5 mL / kg / h) followed by a 3-hour urine output of less than 0.5 mL / kg / h can predict the risk of kidney injury earlier than the RIFLE criteria. The detector Foley system can predict AKI risk 3 hours earlier than the current RIFLE criteria.

[0326] Figures 55B-55E are additional examples showing possible methods for predicting risk of kidney injury earlier than the RIFLE criteria. Figure 55B illustrates an algorithm that uses the trend of urine volume decline data over several hours to predict risk of kidney injury before three consecutive hours of urine output below 0.5 mL / kg / h. Figure 55C illustrates an algorithm that uses a moving average of urine volume over several hours to predict risk of kidney injury before three consecutive hours of urine output below 0.5 mL / kg / h. Figure 55D illustrates an algorithm that uses a moving average of urine volume over several hours to predict risk of kidney injury. Figure 55E illustrates an algorithm that uses a more complex analysis of multiple hours of urine output data to predict risk of kidney injury.

[0327] The Foley system for detection can predict AKI risk up to 1 hour earlier than the RIFLE criteria. Alternatively, the Foley system for detection can predict AKI risk up to 2 hours earlier than the RIFLE criteria. Alternatively, the Foley system for detection can predict AKI risk up to 3 hours earlier than the RIFLE criteria. Alternatively, the Foley system for detection can predict AKI risk up to 4 hours earlier than the RIFLE criteria. Alternatively, the Foley system for detection can predict AKI risk up to 5 hours earlier than the RIFLE criteria. Alternatively, the Foley system for detection can predict AKI risk up to 6 hours earlier than the RIFLE criteria.

[0328] Alternatively, the Foley system for detection can predict AKI risk more than 1 hour earlier than the RIFLE criteria. Alternatively, the Foley system for detection can predict AKI risk more than 2 hours earlier than the RIFLE criteria. Alternatively, the Foley system for detection can predict AKI risk more than 3 hours earlier than the RIFLE criteria. Alternatively, the Foley system for detection can predict AKI risk more than 4 hours earlier than the RIFLE criteria. Alternatively, the Foley system for detection can predict AKI risk more than 5 hours earlier than the RIFLE criteria. Alternatively, the Foley system for detection can predict AKI risk more than 6 hours earlier than the RIFLE criteria.

[0329] The Foley system for detection can predict kidney injury up to 1 hour earlier than the RIFLE criteria. Alternatively, the Foley system for detection can predict kidney injury up to 2 hours earlier than the RIFLE criteria. Alternatively, the Foley system for detection can predict kidney injury up to 3 hours earlier than the RIFLE criteria. Alternatively, the Foley system for detection can predict kidney injury up to 4 hours earlier than the RIFLE criteria. Alternatively, the Foley system for detection can predict kidney injury up to 5 hours earlier than the RIFLE criteria. Alternatively, the Foley system for detection can predict kidney injury up to 6 hours earlier than the RIFLE criteria.

[0330] Alternatively, the Foley system for detection can predict kidney damage more than one hour earlier than the RIFLE criteria. Alternatively, the Foley system for detection can predict kidney damage more than two hours earlier than the RIFLE criteria. Alternatively, the Foley system for detection can predict kidney damage more than three hours earlier than the RIFLE criteria. Alternatively, the Foley system for detection can predict kidney damage more than four hours earlier than the RIFLE criteria. Alternatively, the Foley system for detection can predict kidney damage more than five hours earlier than the RIFLE criteria. Alternatively, the Foley system for detection can predict kidney damage more than six hours earlier than the RIFLE criteria.

[0331] The Foley system for detection can predict renal failure up to 1 hour earlier than the RIFLE criteria. Alternatively, the Foley system for detection can predict renal failure up to 2 hours earlier than the RIFLE criteria. Alternatively, the Foley system for detection can predict renal failure up to 3 hours earlier than the RIFLE criteria. Alternatively, the Foley system for detection can predict renal failure up to 4 hours earlier than the RIFLE criteria. Alternatively, the Foley system for detection can predict renal failure up to 5 hours earlier than the RIFLE criteria. Alternatively, the Foley system for detection can predict renal failure up to 6 hours earlier than the RIFLE criteria.

[0332] Alternatively, the Foley system for detection is capable of predicting renal failure more than one hour earlier than the RIFLE criteria. Alternatively, the Foley system for detection is capable of predicting renal failure more than two hours earlier than the RIFLE criteria. Alternatively, the Foley system for detection is capable of predicting renal failure more than three hours earlier than the RIFLE criteria. Alternatively, the Foley system for detection is capable of predicting renal failure more than four hours earlier than the RIFLE criteria. Alternatively, the Foley system for detection is capable of predicting renal failure more than five hours earlier than the RIFLE criteria. Alternatively, the Foley system for detection is capable of predicting renal failure more than six hours earlier than the RIFLE criteria.

[0333] Some embodiments of the Foley system for detection may identify RIFLE risk 3 hours earlier than would be predicted by traditional RIFLE criteria. Some embodiments of the Foley system for detection may identify RIFLE risk 1-3 hours earlier than would be predicted by traditional RIFLE criteria. Some embodiments of the Foley system for detection may identify RIFLE risk 1-2 hours earlier than would be predicted by traditional RIFLE criteria. Some embodiments of the Foley system for detection may identify RIFLE risk 3-5 hours earlier than would be predicted by traditional RIFLE criteria.

[0334] Some embodiments of the Foley system for detection may identify RIFLE injuries 9 hours earlier than would be predicted by traditional RIFLE criteria. Some embodiments of the Foley system for detection may identify RIFLE injuries 1 to 3 hours earlier than would be predicted by traditional RIFLE criteria. Some embodiments of the Foley system for detection may identify RIFLE injuries 3 to 5 hours earlier than would be predicted by traditional RIFLE criteria. Some embodiments of the Foley system for detection may identify RIFLE injuries 5 to 8 hours earlier than would be predicted by traditional RIFLE criteria. Some embodiments of the Foley system for detection may identify RIFLE injuries 8 to 9 hours earlier than would be predicted by traditional RIFLE criteria. Some embodiments of the Foley system for detection may identify RIFLE injuries 9 to 10 hours earlier than would be predicted by traditional RIFLE criteria.

[0335] While Figures 55A-55E illustrate algorithms that use urine volume data over time, other parameters besides or in addition to urine volume can be used in the disease prediction or identification algorithms. For example, intra-abdominal pressure, temperature, respiratory rate, and / or heart rate data over time can also be factored into AKI risk algorithms. For example, renal perfusion and glomerular filtration gradient are affected by lAP, and lAP often increases prior to oliguria and elevated serum creatinine.

[0336] FIGS. 56A-56C illustrate a Foley sensing system according to one embodiment, including a peristaltic pump. In some embodiments, the pump may be integrated into the monitor / controller and reservoir or cassette. A peristaltic pump can be used in any of the embodiments disclosed herein that include a pump. FIG. 56A illustrates a cassette 1022 including a flexible membrane 5602. The flexible membrane forms a space between the membrane and the relatively rigid cassette. Fluid is forced through the space by the rolling action of rollers 5604. Fluid channels 5606 and 5608 are shown here as part of the cassette. As the pump rollers roll over the flexible membrane, fluid is forced from input fluid channel 5606, through the membrane space, and out output fluid channel 5608. In this manner, the peristaltic pump moves fluid from the drainage tube, through the input fluid channel, through the membrane space, and out the output channel into the reservoir region of the cassette (not shown).

[0337] FIG. 56B is a side view showing the cassette including membrane 5602 and output channel 5608.

[0338] 56C is a side view of the cassette showing a peristaltic pump 5610 engaged with the cassette. As the pump 5610 rotates, rollers 5604 roll around the membrane, forcing fluid into the reservoirs of the cassette. The pump may be integrated into the monitor / controller.

[0339] Although only one pump is shown here, more than one may be provided. The same pump or a separate pump may be used to apply negative pressure to the drainage tube and empty the cassette reservoir. The pump may have two rollers, one roller, or more than two rollers. The channels may be configured in any arrangement that allows the pump to function properly. The pump may operate continuously or intermittently.

[0340] 57A-57C show example screenshots of embodiments disclosed herein. These screenshots may be displayed on the monitor / controller or remotely, such as on a computer or tablet. These screenshots may be particularly applicable to embodiments including controlled feedback loops or loop controls, such as the embodiments shown in FIGS. 26-30.

[0341] The screen shown in FIG. 57A is for a specific patient. The patient ID number and / or patient name may also be displayed. Other patient vitals, such as weight, age, and gender, may also be included on the display. This screen offers three display options: Fluid Balance, Vitals, and Risk Indicators. These display options can be selected by clicking tab 5702, tab 5704, or tab 5706, respectively. In FIG. 57A, the Fluid Balance tab is selected. The desired fluid balance is indicated by dotted line 5708. The actual fluid balance over time is indicated by solid line 5710. The current fluid balance is indicated by symbol 5712. This screen also shows the various status and several settings of various types of devices that may or may not be connected to the patient.

[0342] For example, the urine output area 5714 displays an option to connect or disconnect the device to the loop control system. Connecting the device can be done through this screen when a sensing Foley catheter according to any embodiment of the Foley catheter system is inserted into the patient. Also displayed are the date of insertion of the sensing Foley catheter and the number of days it has been in place. The urine output rate and / or volume can be used for fluid balance analysis by the loop control unit.

[0343] The Enteral Nutrition field 5716 can indicate whether the feeding device is connected to a loop controller and what model it is. Other settings can be configured, such as the amount and rate of delivery. The rate and / or amount can be used in fluid balance analysis by the loop controller. In some feeding tube models, gastric residual volume (GRV) or gastric emptying 5724 can be detected and incorporated into the fluid balance analysis.

[0344] The IV Infusion Pump field 5723 can indicate whether an infusion pump is connected to the loop controller and what model it is. Other settings can include the infusion volume and infusion rate. The infusion rate and / or volume can be used for fluid balance analysis by the loop controller.

[0345] The wound drainage field 5722 can indicate whether a wound drainage system is connected to the loop control and what model it is in. The wound drainage rate and / or volume can be used for fluid balance analysis by the loop control.

[0346] Also shown are a pulse oximeter area 5718 and an electrocardiogram area 5720. These are not directly related to fluid balance, but may also be monitored by the loop control. These sensors may be part of a Foley system for detection, for example.

[0347] The loop controller collects data from various fluid input and output devices and controls these devices to maintain a desired fluid balance within the patient's body. For example, if the patient is urinating at a higher volumetric rate than the rate of fluid input through nutritional delivery and / or infusion, the patient's fluid balance will be more negative. If the fluid balance falls below the desired range, the nutritional delivery rate and / or infusion rate can be increased to bring the fluid balance back within the desired range. Alternatively, if the fluid balance is too positive (too much fluid), the nutritional delivery rate and / or infusion rate can be decreased until the fluid balance returns to the desired range. Other fluid output measurements may also be included as appropriate, such as wound drainage, as shown in area 5722. Fluid losses through sweat, exhalation, and bowel movements may also be considered by the loop controller in the fluid balance analysis. Although connections for these devices are not shown on this screen, they may be included. The desired fluid balance range may be set via settings such as area 5725 shown here.

[0348] The various devices to be connected may be automatically detected via mechanisms such as Bluetooth®, or may be manually connected.

[0349] FIG. 57B shows another example screen of the loop controller system. This screen shows an example of what may be displayed within the "Vitals" tab area. This area displays one or more of the patient's vital signs over time. The time axis can be changed, for example, via button 5726. This displays the patient's temperature, heart rate, respiratory rate, urine volume (or alternatively, urine output rate), intraperitoneal pressure, and pulse oximeter measurements over time. Other vital signs may also be displayed. For example, an electrocardiogram, weight, blood pressure, etc. may be displayed. Some or all of these measurements may be collected by a sensing Foley catheter system.

[0350] Figure 57C shows an example of the back screen of the "Fluid Balance" tab, with the settings area shown in Figure 57A minimized at the bottom of the screen. The ongoing and current actual and desired fluid balance are displayed at the top of the screen. Also displayed over time are IV infusion volumes, enteral nutrition volumes, urine output, and wound drainage volumes, if desired. In this example, the patient is not using a wound drainage device, so no data is displayed in the graphs.

[0351] The risk area of the display can indicate risk for various conditions based in part or in whole on data collected from the sensing Foley catheter system and / or other devices. For example, AKI risk, sepsis risk, and other risks can be assessed by the control unit and displayed here. Settings for various parameters used in risk assessment can also be entered or collected by the control unit. For example, a patient's weight can be entered into the risk profile.

[0352] 58A and 58B illustrate a Foley catheter sensing system according to one embodiment, including analysis and recording of various urine parameters. FIG. 58A shows a cassette for collecting urine output, which includes an optically transparent portion 5804 and a test strip 5806. The test strip 5806 includes one or more test strip segments 5808. The test strip segments can change color based on various urine parameters. For example, the test strip segments may test for the presence of white blood cells, nitrite, urobilinogen, protein, hemoglobin, ketone, bilirubin, acetone, glucose, hormones, drugs, creatinine, or other entities, or the test strip can determine urine pH, specific gravity, color, or other parameters. The test strip segments can also test for pathogens.

[0353] The camera 5802 is preferably a visible light camera, but may also be a camera that detects wavelengths of light outside the visible spectrum and may be integrated into the monitor / controller. The camera can be moved up and down automatically by the control, or manually, to capture images of the test strip segments in various rows on the test strip. Alternatively, the camera lens may have a wide enough angle to capture an area large enough to monitor the liquid level over the required range. Alternatively, multiple cameras may be mounted and in communication with the control. These camera options apply to any embodiment incorporating any type of camera and / or wavelength detector disclosed herein.

[0354] The test strip 5806 may include multiple test strip segments in multiple rows. Preferably, each row is identical, but may be different. Each row includes one or more test strip segments, each capable of testing a different parameter. For example, the test strip may include two or more rows with two different test strip segments. Alternatively, the test strip may include two or more rows with three different test strip segments. Alternatively, the test strip may include two or more rows with four different test strip segments. Alternatively, the test strip may include two or more rows with five different test strip segments. Alternatively, the test strip may include two or more rows with six different test strip segments. Alternatively, the test strip may include two or more rows with seven different test strip segments. Alternatively, the test strip may include two or more rows with eight different test strip segments. Alternatively, the test strip may include two or more rows with nine different test strip segments. Alternatively, the test strip may include two or more rows of ten different test strip segments. Alternatively, the test strip may include two or more rows of two or more different test strip segments. Alternatively, the test strip may include two or more rows of three or more different test strip segments. Alternatively, the test strip may include two or more rows of four or more different test strip segments. Alternatively, the test strip may include two or more rows of six or more different test strip segments.

[0355] FIG. 58B shows a test strip 5806 having ten rows of seven different test strip segments.

[0356] To expose different rows of test strip segments to urine as urine is collected, the test strip array may be enclosed within a urine collection chamber, as shown in FIG. 58A. As urine collects in the chamber, it may first contact the lowest segment of the test strip segments. Alternatively, the bottom (first) row of test strip segments may be above a level corresponding to the emptying volume of the collection chamber. In this embodiment, urine may first contact the lower row of test strip segments by a controller controlling the pump to draw a vacuum via the cassette pump interface 1148. The vacuum drawn by the vacuum pump temporarily elevates the row of urine within the cassette cylinder 5809 via vacuum path 5810, thereby allowing the urine to contact subsequent rows of test strip segments. The controller may be programmed to periodically draw a vacuum, subsequently exposing higher rows of test strip segments to urine and testing the collected urine. In this manner, multiple tests can be performed individually by exposing new test strips to urine. The number of test strip rows corresponds to the number of fresh tests that can be performed on each test strip. For example, row 1 of the test paper is used first, then row 2, and so on.

[0357] The camera may move incrementally higher as each row of the test strip is used, or alternatively, the camera's viewing angle may change to view subsequent rows of the test strip.

[0358] The test strips can be replaced via a sterile cartridge, which can be removed and replaced.

[0359] The camera can detect the color of the test strip segment row and compare it to a standard color array to determine whether any of the parameters of the test strip segment indicate that the urine is outside of its parameter range. The camera may be calibrated to the standard color array.

[0360] Other camera and / or test strip configurations are also contemplated. For example, the reading of the test strip can be done manually rather than automatically via the camera / controller.

[0361] FIG. 59 illustrates a sensing Foley catheter system according to one embodiment, including a pump 5902 that acts directly on or in line with the urinary drainage lumen 1012. This type of pump may be a positive displacement pump, a peristaltic pump, a centrifugal pump, or any other type of pump, including those described herein. FIG. 59 also illustrates a pump bypass lumen 5904, which connects to the urinary drainage line both before and after the pump 5902. The bypass lumen 5904 includes a one-way valve 5906. This embodiment operates similarly to other embodiments disclosed herein, except that the bypass lumen allows urinary drainage to bypass the pump under these or other circumstances when a malfunction occurs or the pump does not pump as fast as the urinary drainage flow, which could cause the pump to block the urinary drainage line. The one-way valve prevents urine from moving upward in the bypass lumen and allows the pump to effectively pull a vacuum on the drainage line, eliminating the airlock. A vent 1180 may be provided to allow air to enter the vent line. Additionally, a vent 5908 may be provided to allow air to escape from the cassette 1022.

[0362] FIG. 60 illustrates an embodiment including a pump mechanism that can be added to any urinary drainage system, including any standard Foley system, having a drainage line, such as drainage line 1012. The add-on pump mechanism can be contained in a container, such as container 6002, that can be placed alongside the drainage line. The pump mechanism, as shown here, can operate similarly to that shown in FIG. 59. The pump mechanism can be connected between the drainage line and the drainage bag or anywhere along the drainage line. The pump mechanism may include a proximal connector and a distal connector.

[0363] FIG. 61 illustrates another example including a pump mechanism that can be added to any urinary drainage system, including any standard Foley system with a drainage line, such as drainage line 1012. The add-on pump mechanism may or may not include an external container. The pump mechanism can be connected between the drainage line and a drainage bag or anywhere along the drainage line. The pump mechanism may include a proximal connector and a distal connector. This embodiment includes an inlet one-way valve 6102 and an outlet one-way valve 6108. Between the two one-way valves is a length of tubing, or reservoir 6104, that remains unobstructed so that urine flow is never interrupted. The pump 6106 may be a simple syringe, a flexible squeeze valve, or a more sophisticated pump mechanism. A filter may be provided between the pump and reservoir 6104. The pump may be either manual or automatic.

[0364] FIG. 62 illustrates an embodiment including a fluid flow meter that can be added to any urinary drainage system, including any standard Foley system, having a drainage line, such as drainage line 1012. The add-on fluid flow meter mechanism 6202 can be contained in a container, such as container 6204, that can be positioned alongside the drainage line. The fluid metering mechanism can be connected between the drainage line and a drainage bag or anywhere along the drainage line. The pump mechanism can include a proximal connector and a distal connector. The fluid flow meter mechanism can be pressure-based, resistance-based, capacitance-based, ultrasound-based, weight-based, or optical-based technology, or any other suitable technology.

[0365] FIG. 63 illustrates one embodiment including a gravimetric fluid flow meter. The weight control unit 6302 includes the capability to measure the weight of the urine collection reservoir, in this case a bag, via weight sensor 6306 and, optionally, the weight of the urinary drainage line via weight sensor 6304, so that the weight / movement of the urinary drainage line can be factored into (e.g., subtracted from) urine flow or total urine output calculations. Urine flow and / or real-time urine volume can be measured and optionally displayed on the weight control unit 6302 or elsewhere. As with any of the embodiments disclosed herein, data from the weight control unit may be transmitted remotely and aggregated, analyzed, etc., on a computer server and / or communicated to various users.

[0366] Figure 64 illustrates a standard Foley catheter system with a standard drainage bag incorporating an embodiment similar to Figures 53, 61, and 63, i.e., a standard Foley catheter and drainage system with the addition of three modular components.

[0367] -Add-on ventilation mechanism, 6402

[0368] -Add-on pump / airlock release mechanism, 6404.

[0369] -Add-on urine volume measuring mechanism, 6406.

[0370] Adding these three add-on features to a standard Foley catheter drainage system not only eliminates airlock but also improves the system by enabling accurate, real-time urine volume measurement. It is also anticipated that these three add-on features may be combined, such as an optical urine volume measurement feature. These features may be used in combination, one, two, or three, on a single system.

[0371] Figures 65A-65D illustrate a Foley catheter system according to one embodiment that includes the ability to measure urine osmolality, which can be used to diagnose, predict, or monitor certain health conditions. Urine osmolality is measured by measuring the rate at which urine passes through a filter of a specific pore size at a specific differential pressure across the filter. In some embodiments, the measurement of urine osmolality may be incorporated into the cassette / monitor of the system. Figure 65A illustrates a cassette 1022 according to one embodiment, including a main urine collection area 6502, a bubble column 6504, a one-way valve 6506, a filter membrane 6508, a first pressure sensor and pump-cassette interface 6510, a second pressure sensor and pump-cassette interface 6512, an ultrasonic (or other) urine volume measurement mechanism 6514, and a one-way emptying valve 6516. Pressure interfaces 6510 and 6512 can measure the pressure in and / or apply positive and / or negative pressure to the main urine collection area 6502 and the bubble column 6504, respectively. Both the one-way valve 6506 and filter membrane 6508 are located at or near the bottom of the cassette where the main urine collection area and bubble column are connected. While the valve 6506 and membrane 6508 are shown overlapping each other here, they would likely be next to each other as close to the bottom of the cassette as possible. While the cassette is collecting urine, the one-way emptying valve 6516 is closed.

[0372] As urine is collected, it moves from the main urine collection area 6502 through the membrane 6508 and into the bubble column 6504, as shown in FIG. 65A. To perform an osmolality measurement, the controller pressurizes the bubble column 6504 via pressure interface 6512, forcing all of the urine in the bubble column through valve 6506 and into the main collection area 6502, as shown in FIG. 65B. The pressure in the main collection chamber 6502 and the bubble column 6504 is monitored via pressure interfaces 6510 and 6512, respectively. When there is no urine in the bubble column, air bubbles pass through the one-way valve 6506. This can be detected by the controller through pressure measurements in the main collection area and the bubble column, at which point the controller knows the bubble column is empty. The controller then reduces the pressure in the bubble column 6504 so that urine can pass from the main collection chamber 6502 through the filter membrane 6508 and into the bubble column 6504. The pressure in the main collection chamber, the bubble column, and the volume of urine in the main collection chamber are monitored. At a given differential pressure (zero or greater), the rate at which urine passes through the filter membrane and into the bubble chamber is related to the osmolality of the urine. Thus, the osmolality of the urine may be measured by the controller. The volume of urine in the main collection area and / or the bubble column can be monitored by ultrasound, pressure, or other mechanisms.

[0373] FIG. 65C shows the cassette after some of the urine has moved from the main collection chamber through the filter membrane and into the bubble column.

[0374] 65D shows an embodiment in which the controller opens the emptying valve 6516 to allow urine to drain from the cassette. The drainage of urine from the cassette may be facilitated by pressurizing the main collection area 6502 and / or the bubble column 6504.

[0375] Osmolality measurements may be taken periodically to measure changes in urine osmolality over time. For example, osmolality measurements may be taken each time the cassette is filled / emptied. Alternatively, osmolality measurements may be taken at specific time intervals.

[0376] The filter membrane may be periodically cleaned by passing pressurized air across the membrane.

[0377] Some embodiments may include conductivity electrodes in or on the cassette to measure the concentration of various conductive and non-conductive solutes in urine, such as salts, sodium (Na), creatinine, urea, uric acid, glucose, potassium, chloride, inorganic phosphate, nitrite, calcium, magnesium, chloride, hormones, vitamins, drugs, etc. The electrodes may be gold or silver plated to prevent biofilm buildup. Biofilm can be removed / prevented using vibration, ultrasound, etc. Non-contact impedance electrodes / meters may also be used.

[0378] Figures 66A and 66B show a cassette according to one embodiment that includes electrodes 6602 for measuring the conductivity of urine within the cassette. Figure 66A shows the front of the cassette, and Figure 66B shows the back of the cassette. The electrodes may be on the inside surface of the cassette, embedded in the walls of the cassette, or located elsewhere.

[0379] FIGS. 67A and 67B illustrate a controller according to one embodiment for use in conjunction with the cassette shown in FIGS. 66A and 66B. FIG. 67A shows the cassette attached to the controller. A display showing a graph 6702 of Na+ concentration over time is also shown. The display may or may not have units. Without units, the number simply indicates a relative value, which is useful for understanding changes. Changes in Na+ (or any other analyte) levels or general conductivity may indicate changes in urine volume or other upcoming health information. For example, urine conductivity may increase before urine volume decreases. In this way, conductivity may be an early indicator of decreased urine volume, which in turn may be an indicator of the patient's health status. Device embodiments can sound an alarm or communicate when certain conductivity parameters, such as a sudden increase or decrease in conductivity, are detected or analyzed.

[0380] Figure 67A shows the control unit of Figure 67A without a cassette installed. Electrode connectors 6704 are shown that contact electrodes 6602 on the cassette. The electrode connectors are now shown within openings 6706 that receive the cassette.

[0381] Some embodiments of the device combine information from different sensors to assess the patient's health status. For example, a combination of high urine volume and high urinary conductivity can be indicative of a particular health condition.

[0382] Different sizes, numbers, types, and / or locations of electrodes can be used to sense different parameters of urine, and it is even possible to sense more than one parameter at a time.

[0383] In some embodiments, the controller is initially in a standby state, and when the controller detects, via sensors such as pressure, volume, ultrasonic, or optical sensors, that urine has first entered the cassette, the controller can automatically wake up and begin functions such as monitoring urine volume and clearing airlocks.

[0384] As with any embodiment disclosed herein, a pressure sensor may be included elsewhere in the system, such as in the barb area, to monitor the pressure (positive or negative) within the system and determine when an optimal pressure is reached for fluid drainage. For example, the monitor / controller may monitor the signal from the pressure sensor at the barb to ensure an optimal pressure range, e.g., approximately 0.5 mmHg (approximately 66.66 Pa). This optimal pressure range allows for proper airlock clearance and fluid drainage without excessive negative pressure on the bladder. This optimal pressure range may be controlled periodically or continuously by the controller controlling a pump that generates negative pressure within the drainage tube. For continuous operation, the monitor / controller may control the pump speed to maintain the appropriate pressure range within the system.

[0385] In some embodiments, a flow meter or flow sensor may be incorporated into the system. For example, a flow meter may be added to the vent tube to monitor airflow and better control the airlock clearance function. The flow rate is sensed by the flow meter and a signal is transmitted to the controller. In some embodiments, the flow sensor or meter may be located elsewhere in the system, for example, in or near the reservoir / cassette.

[0386] For example, an airlock in the drainage line will prevent air from flowing through the vent tube. This information can be used by the controller to initiate an airlock clearance cycle, such as by applying negative pressure to the cassette and drainage line. If there is air flow through the vent tube, the controller may determine that an airlock is not present. In embodiments that also include a flow sensor in the reservoir / cassette, the controller may be able to determine where in the system the blockage is. For example, it may be able to determine whether the blockage is in the drainage tube, the vent tube, or the cassette. For example, the controller may be able to determine if the user forgot to unclamp the drainage line and indicate this to the user. The controller can detect the flow rate when a vacuum is pulled by a vacuum pump. By detecting the flow rate within the cassette, the location of the blockage can be identified. A low flow rate indicates a blockage closer to the cassette, while a high flow rate (but below an expected cutoff value) indicates a blockage further from the cassette.

[0387] As with any embodiment disclosed herein, an overflow barrier or overflow path may be incorporated into the reservoir / cassette.

[0388] Some embodiments of the Foley system for sensing may incorporate comprehensive "smart" sensing, including any of the sensing types disclosed herein. For example, a "smart" Foley catheter sensing system may include:

[0389] -Oxygen saturation by detection mechanisms such as pulse oximetry;

[0390] - electrocardiogram, i.e. via electrodes in contact with the urethra, bladder, or skin;

[0391] - Urinary parameters by visible or other wavelength cameras, including spectroscopy,

[0392] - measuring the capacitance of tissue and / or urine via electrodes in contact with the urethra, bladder, skin, or electrodes placed in a reservoir / cassette in contact with urine;

[0393] - Measuring tissue and / or urine conductivity via electrodes in contact with the urethra, bladder, skin, or electrodes placed within a reservoir / cassette in contact with urine,

[0394] -Urine chemistry analysis via sensors in the catheter and / or drainage tube or monitor / cassette, including albumen, bilirubin, red blood cells, hemoglobin, myoglobin, hemolysis, urine pH, bile, urea, sodium, potassium, calcium, creatinine, etc.

[0395] -Heart rate

[0396] -Respiration rate

[0397] -blood pressure

[0398] - Sleep analysis (ie duration and / or quality) - This can be achieved by analysis of blood pressure, respiratory rate, heart rate, IAP, etc.

[0399] -Central venous pressure.

[0400] It should be noted that elements disclosed in association with any embodiment herein may be used with any other embodiment disclosed herein.

Claims

1. a pump mechanism fluidly connectable at a first end to a portion of the drainage line; a venting mechanism having a one-way valve for venting and connectable at a first end in fluid communication with the drainage catheter and the drainage line; an inlet one-way valve disposed at the inlet of the portion between the drainage catheter and the pump mechanism; an outlet one-way valve disposed at an outlet of the portion distal to the pump mechanism; Equipped with the pump mechanism is configured to generate a negative pressure in the drainage line when in communication with the drainage line; the one-way vent valve is configured to open to the environment when the vent mechanism is connected at the first end and the drainage line is at a pressure lower than ambient pressure so that an airlock is not formed in the drainage line.

2. 10. The system of claim 1, further comprising a bypass lumen fluidly connected along the drainage line at a first bypass end located proximal to the pump mechanism and at a second bypass end located distal to the pump mechanism.

3. The system of claim 1 , further comprising the drainage line fluidly connected to the pump mechanism.

4. The system of claim 1 further comprising the drainage catheter comprising a Foley catheter.

5. 2. The system of claim 1, wherein the venting mechanism is connectable in fluid communication with the drainage line at the first end through a sampling port of the drainage system, including within the drainage line, as part of the drainage catheter, or between the drainage catheter and the drainage line.

6. 2. The system of claim 1, wherein the venting mechanism is connectable at the first end to be in fluid communication with the proximal end of the drainage catheter and is further connectable at a second end to be in fluid communication with the distal end of the drainage line.

7. The system of claim 1 , wherein the pump mechanism is configured to periodically generate the negative pressure in the drainage line.

8. The system of claim 1 , wherein the pump mechanism is configured to continuously generate the negative pressure in the drainage line.

9. The system of claim 1 , wherein the pump mechanism is directly connectable to the drainage line.

10. The system of claim 1 , wherein the pump mechanism comprises a peristaltic pump.

11. The system of claim 1 , wherein the pump mechanism comprises a positive displacement pump.

12. The system of claim 1 , wherein the pump mechanism comprises a centrifugal pump.

13. The system of claim 1 , wherein the pump mechanism is fluidly coupled at a first end to the portion of the drainage line and at a second end to a reservoir.

14. The system of claim 1 , further comprising a fluid flow meter configured to communicate with the drainage line.

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