Catheter system with pressure control device

Abstract

The system includes a catheter and a pressure management device. The catheter includes a cuff, a resilient device, a drain passage, and a first fitting. The cuff defines a chamber and has a deflated state and an inflated state. The resilient device is disposed within the chamber and has a compressed state and an expanded state. The resilient device is configured to expand from the compressed state to the expanded state upon transition of the cuff from the deflated state to the inflated state. The drain passage extends from the cuff to an exhaust port. The first fitting is in fluid communication with the chamber. The pressure management device includes a second fitting that engages the first fitting and at least one check valve in fluid communication with the second fitting. In this embodiment, the at least one check valve includes an inlet check valve in fluid communication with the second fitting and an outlet check valve in fluid communication with the second fitting.

Description

Cross - Reference to Related Disclosures

[0001] This disclosure claims the benefit of U.S. Application No. 63 / 173,814, filed Apr. 12, 2021, and U.S. Application No. 63 / 186,528, filed May 10, 2021, the disclosures of which are incorporated herein by reference in their entireties.

Technical Field

[0002] This disclosure generally relates to catheters and related systems, and more particularly, but not limited to, bowel management catheters and related systems.

Background Art

[0003] Indwelling catheters for fecal management are often used to manage liquid or semi - liquid feces of non - ambulatory inpatients. Fecal incontinence catheters are considered standard in most intensive care units (ICUs) for managing non - ambulatory inpatients who have fecal incontinence due to liquid or semi - liquid feces. However, one of the patient risks when using an invasive device such as a fecal incontinence catheter is the increase in rectal pressure due to the indwelling balloon. To effectively fix the indwelling balloon, the balloon needs to be inflated sufficiently, which results in an increase in balloon pressure and, in turn, an increase in rectal pressure. Such high rectal pressure over a long period during the use of the device can cause various adverse events such as pressure ulcers and rectal bleeding. Therefore, these two factors represent conflicting needs in the design of indwelling balloons for essentially all indwelling catheters, such as fecal, urinary, and airway catheters.

[0004] To address this unmet patient need, various designs have been developed. For example, European Patent No. 2,278,945 discloses the use of a filling indicator. More specifically, the '945 patent discloses a rectal drainage device comprising a tubular element having an inflatable balloon at its distal end for securing the rectal drainage device to the rectum. The device may include first and second auxiliary lumens communicating with the inflatable balloon, providing independent inflation and pressure monitoring pathways connected to the balloon. The device may include a pressure state indicator defined by a mechanical element configured to invert between a first and second state or shape in response to sensed pressure. The pressure state indicator can also be used for intestinal drains.

[0005] Another conventional approach is disclosed in U.S. Patent No. 8,939,952, which uses a double balloon including an air pocket. More specifically, the '952 patent discloses a rectal instrument comprising a tubular member defining a passage for bodily waste and first and second inflatable chamber portions supported on the tubular member to form internal and external seals to the anus. One or both of the inflatable chamber portions have a partially flared shape. The second inflatable portion of the chamber has a low profile and a concave sealing surface. The inflatable chamber portions are at least partially defined by a common flexible membrane constrained near an intermediate region to define a narrow waist between the two inflatable chamber portions.

[0006] Another conventional approach, including the use of a double balloon with an air pocket, is disclosed in PCT Publication No. WO 2007 / 118621 A1. Publication No. 621 discloses an occlusion system for managing rectal or anal incontinence, comprising a shaft element having a distal end and a proximal end, with a lumen extending from the distal end to the proximal end of the shaft element, and a balloon that is adhesively and sealably attached to the shaft element and can be filled with a filling medium via a filling line. The balloon is formed from a tubular portion and, when filled with the filling medium, forms a first balloon shape as an intrarectal balloon and a second balloon shape as an adjacent balloon, which are shaped such that they are separated from each other by a stenosis. The distal end of the shaft element is designed with an end cap with a tip, and at a position away from the tip, there is at least one gas inlet opening communicating with the lumen of the shaft element. The proximal end of the shaft element is connected to an outlet tube, which extends laterally with respect to the longitudinal axis of the shaft element and has an outlet opening at its end that communicates with the lumen.

[0007] Another conventional approach is disclosed in European Patent No. 2,575,703, which generally discloses a catheter comprising a compressible foam. More specifically, the '703 patent discloses a drainage device comprising a distal portion having an expandable retaining cuff for holding the distal portion in the rectum, intestine, or urinary tract. The inflation of the cuff is controlled by a combination of: (a) an elastically deformable device for promoting cuff inflation; (b) a chamber containing a variable-size fluid; and (c) a fluid transfer damper for restricting the flow of fluid into the chamber when the chamber is resized.

[0008] Many existing approaches, including those described in the documents referenced above, may have one or more drawbacks or limitations. For example, certain existing approaches can only mitigate the risk of balloon overinflation, rather than the pressure present during standard use. Certain existing approaches still cannot reduce high balloon pressure, especially when the indwelling balloon is compressed by the rectal wall during defecation or patient movement. Certain existing approaches require the use of a fluid transfer damper to restrict the flow of fluid in and out of the indwelling balloon, but the slow response of the fluid transfer damper means that relatively high balloon pressure does not necessarily decrease quickly. For these reasons in particular, further improvements are still needed in this field. [Overview of the Initiative]

[0009] An example of a system includes a catheter and a pressure management device. The catheter includes a cuff, an elastic device, a discharge passage, and a first fitting. The cuff defines a chamber and has a contracted state and an expanded state. The elastic device is located within the chamber and has a compressed state and an expanded state. The elastic device is configured to transition the cuff from a contracted state to an expanded state by expanding from a compressed state to an expanded state. The discharge passage extends from the cuff to the discharge port. The first fitting is in fluid communication with the chamber. The pressure management device includes a second fitting that engages with the first fitting and at least one check valve that is in fluid communication with the second fitting. In certain embodiments, the at least one check valve has an inlet check valve that is in fluid communication with the second fitting and an outlet check valve that is in fluid communication with the second fitting. Further embodiments, forms, features, and aspects of the present application will become apparent from the description and drawings provided herein. [Brief explanation of the drawing]

[0010] [Figure 1] Figure 1 is a cross-sectional view of a catheter according to a specific embodiment. [Figure 2] Figure 2 is a schematic diagram of a system according to a specific embodiment, which includes the catheter and pressure management device shown in Figure 1. [Figure 3] Figure 3 is a cross-sectional view of the pressure control device shown in Figure 2. [Figure 4] Figure 4 is a schematic flowchart of the process according to a specific embodiment. [Modes for carrying out the invention]

[0011] While the concepts of this disclosure are subject to various modifications and alternative forms, specific embodiments are shown in the drawings as examples and described in detail herein. However, it should be understood that the concepts of this disclosure are not intended to be limited to the specific forms disclosed, but rather are intended to cover all modifications, equivalents, and alternatives that conform to the scope of this disclosure and the appended claims.

[0012] References to “one embodiment,” “one example embodiment,” and “exemplary embodiment” in this specification indicate that the described embodiments may include certain features, structures, or characteristics, but not all embodiments will include those specific features, structures, or characteristics. Furthermore, such expressions do not necessarily refer to the same embodiment. References to “preferred” components or features may indicate the desirability of certain components or features in a particular embodiment, but it should be further understood that this disclosure is not so limited with respect to other embodiments in which such components or features may be omitted. Furthermore, where certain features, structures, or characteristics are described in relation to an embodiment, whether expressly described or not, it is presented that implementing such features, structures, or characteristics in relation to other embodiments is within the knowledge of those skilled in the art.

[0013] Furthermore, please understand that items in a list in the form of "at least one of A, B, or C" may mean (A), (B), (C), (A and B), (B and C), (A and C), or (A, B and C). Similarly, items listed in the form of "at least one of A, B, or C" may mean (A), (B), (C), (A and B), (B and C), (A and C), or (A, B, C). Items listed in the form of "A, B, and / or C" may also mean (A), (B), (C), (A and B), (B and C), (A and C), or (A, B, and C). Furthermore, with respect to the claims, the use of phrases such as “one (a),” “one (an),” “at least a portion,” and / or “at least a portion” should not be interpreted as limiting such elements to only one unless otherwise stated, and the use of phrases such as “at least a portion,” and / or “a portion,” should be interpreted as encompassing both embodiments that include only a portion of such elements and embodiments that include the whole of such elements, unless otherwise stated.

[0014] In drawings, certain structural or methodological features may be shown in a specific arrangement and / or order. However, it should be understood that such a specific arrangement and / or order is not necessarily required. Rather, in some embodiments, such features may be arranged in a different manner and / or order than those shown in the illustrative drawings unless otherwise specified. Furthermore, the inclusion of structural or methodological features in a particular drawing does not mean that such features are required in all embodiments, and in some embodiments they may be omitted or combined with other features.

[0015] Where used herein, the term “about” may be used to modify quantitative expressions that may vary acceptablely from stated values. In certain embodiments, the term “about” may mean a 10% tolerance. For example, a pressure described as “about 10 mmHg above atmospheric pressure” may be in the range of 9 to 11 millimeters of mercury (mmHg) above atmospheric pressure. Also, the term “atmospheric pressure” refers to standard atmospheric pressure (i.e., about 760 mmHg).

[0016] Referring to Figure 1, an indwelling catheter 100 according to a specific embodiment is shown. The catheter 100 generally includes a tubular body portion 110 having a proximal end portion 112 and a distal end portion 114 opposite it, a cuff 120 positioned on the distal end portion 114 of the body portion 110, an elastic device 130 positioned within the chamber 122 of the cuff 120, an inflatable / deflated lumen 140 extending from the cuff 120 to an inflatable / deflated port 102, and a first attachment 104 attached to the inflatable / deflated port 102. In the illustrated example, the indwelling catheter 100 is provided in the form of a fecal catheter, with the distal end portion 114 configured for insertion into the patient's rectum. The catheter 100 may also be provided in other forms, such as a urinary catheter or an airway catheter.

[0017] The catheter body portion 110 extends from the proximal end portion 112 to the distal end portion 114, defining a drainage passage 116 having an inlet 115 formed at the distal end portion 114 and an outlet or drain 113 formed at the proximal end portion 112. The passage 116 is configured to allow a fluid (e.g., air, liquid, or semi-liquid) to flow from the inlet 115 to the outlet 113. For example, in the illustrated example, drainage flows from the inlet 115 to the outlet 113 and is discharged from the outlet 113. In certain embodiments, such as when the catheter 100 is used as an airway catheter, the passage 116 can further facilitate the flow of fluid (e.g., air) from the outlet 113 to the inlet 115, for example, during inhalation by the patient.

[0018] The cuff 120 is located at the distal end portion 114 of the main body portion 110 and defines a chamber 122 in which the elastic device 130 is housed. Although other configurations are possible, the illustrated cuff 120 is provided in the form of a substantially toroidal balloon surrounding the inlet 115 of the discharge passage 116. As described herein, the cuff 120 has a contracted state corresponding to a collapsed state of the elastic device 130 and an expanded state corresponding to an expanded state of the elastic device 130. During the contraction of the cuff 120, the cuff 120 compresses or collapses the elastic device, causing the elastic device to store mechanical energy that can be released to inflate the cuff 120.

[0019] The elastic device 130 is located within the chamber 122 and has a compressed state and an expanded state. In the illustrated example, the elastic device 130 is provided in the form of an open-cell foam 132, such as open-cell polyurethane foam. The elastic device 130 is also intended to be provided in other forms, such as a form including one or more springs. As described herein, the elastic device 130 is configured to compress when the cuff 120 is deflated to insert the cuff 120 into a patient's cavity (e.g., the rectal cavity), and then expand to cause the cuff 120 to inflate in order to secure the cuff 120 in the cavity.

[0020] The inflatable / deflated lumen 140 has a distal end 142 that opens to the chamber 122, a proximal end 144 connected to the inflatable / deflated port 102, and optionally an elongated portion 146 that extends between the distal end 142 and the proximal end 144, connecting the distal end 142 and the proximal end 144, so that the chamber 122 is in fluid communication with the inflatable / deflated port 102. As a result, the cuff 120 is operable to inflate and deflate via the first fitting 104 as described herein. The first fitting 104 may be provided, for example, in the form of a normally closed check valve configured to transition to an open state when engaged with a mating syringe 220 or a pressure control device 210, as described herein.

[0021] Referring further to Figure 2, a system 200 according to a particular embodiment is shown. The system 200 includes a catheter 100 and a pressure control device 210 according to a particular embodiment, and may further include a negative pressure generator such as a syringe 220. In a particular embodiment, the pressure control device 210 may be attached to the proximal end portion of the catheter 100 to prevent loss of the pressure control device 210. For example, the pressure control device 210 may include a strap that secures the pressure control device 210 to a portion of the catheter 100 near the attachment 104 of the expansion / contraction port 102.

[0022] Referring further to Figure 3, the pressure control device 210 generally includes a body 212 defining a fluid passage 213, a second fitting 214 connected to a first branch 215 of the fluid passage 213, an inlet check valve 216 connected to a second branch 217 of the fluid passage 213, and an outlet check valve 218 connected to a third branch 219 of the fluid passage 213. In the illustrated example, the fluid passage 213 is arranged in a generally T-shape, with the third branch 219 substantially perpendicular to the first branch 215 and the second branch 217. The fluid passage 213 may take other forms. For example, the fluid passage 213 may be provided in a substantially Y-shape configuration with branches 215, 217, and 219 extending at oblique angles to each other, or in a V-shape configuration with the first branch 215 omitted. The second fitting 214 is configured to fit with the first fitting 104 such that the fluid passage 213 communicates with the expansion / contraction lumen 140 when the fittings 104 and 214 are engaged with each other.

[0023] The inlet check valve 216 is normally closed and has a first cracking pressure, and is configured to allow the flow of fluid from the first pressure source to the fluid passage 213 when the pressure of the first pressure source exceeds the pressure in the fluid passage 213 by at least the first cracking pressure. When the pressure management device fixture 214 is fixed to the catheter fixture 104, the pressure in the fluid passage 213 corresponds to the pressure in the cuff chamber 122. Although other pressure sources are conceivable, in the illustrated embodiment, the first pressure source is ambient air. The illustrated inlet check valve 216 is provided in the form of a duckbill valve, but it is also contemplated that the inlet check valve 216 may be provided in another form such as an umbrella valve, a disk valve, a diaphragm valve, or an open vent.

[0024] The outlet check valve 218 is normally closed and has a second cracking pressure, and is configured to allow the flow of fluid from the fluid passage 213 to the second pressure source when the pressure in the fluid passage 213 exceeds the pressure of the second pressure source by at least the second cracking pressure. As described above, when the pressure management device fixture 214 is fixed to the catheter fixture 104, the pressure in the fluid passage 213 corresponds to the pressure in the cuff 122. Although other pressure sources are conceivable, in the illustrated embodiment, the second pressure source is ambient air. The illustrated outlet check valve 218 is provided in the form of a duckbill valve, but it is also contemplated that the outlet check valve 218 may be provided in another form such as an umbrella valve, a disk valve, or a diaphragm valve.

[0025] In certain embodiments, the inlet check valve 216 and the outlet check valve 218 can be selected as the same type of check valve (e.g., any of a duckbill valve, an umbrella valve, a disk valve, a diaphragm valve, an open vent). In certain embodiments, the inlet check valve 216 and the outlet check valve 218 can be selected as different types of check valves.

[0026] As described herein, the pressure management device 210 is configured to maintain the pressure within the cuff chamber 122 within a predetermined pressure range having a minimum pressure corresponding to the cracking pressure of the inlet check valve 216 and a maximum pressure corresponding to the cracking pressure of the outlet check valve 218. In certain embodiments, the cracking pressure of the inlet check valve 216 may be 5 mmHg or more and 15 mmHg or less. In certain embodiments, the cracking pressure of the inlet check valve 216 may be about 10 mmHg (e.g., 9 mmHg to 11 mmHg). In certain embodiments, the cracking pressure of the outlet check valve 218 may be about 30 mmHg (e.g., 27 mmHg to 33 mmHg). In certain embodiments, the cracking pressure of the outlet check valve 218 may be about 20 mmHg (e.g., 18 mmHg to 22 mmHg). In certain embodiments, the cracking pressure of the outlet check valve 218 may be about 10 mmHg (e.g., 9 mmHg to 11 mmHg). In certain embodiments, the cracking pressure of the outlet check valve 218 may be 4 to 6 mmHg or about 5 mmHg (e.g., 4.5 mmHg to 5.5 mmHg).

[0027] The syringe 220 generally includes a body portion 212 that partially defines a fluid chamber 223, a third fitting 224, and a plunger 226 slidably attached to the body portion 222. The third fitting 224 is configured to mate with the first fitting 104 such that when the fittings 104, 224 are engaged with each other, the fluid chamber 223 communicates with the expansion / contraction lumen 140. When engaged in this manner, the retraction of the plunger 226 expands the fluid chamber 223, thereby generating a negative pressure within the cuff chamber 122. The negative pressure within the cuff chamber 122 can also be generated by another method, such as the use of a pump.

[0028] As described above, each of the pressure control device attachment 214 and the syringe 224 is configured to mate with the catheter attachment 104. Those skilled in the art will be able to easily select the appropriate attachments to be used as attachments 104, 214, and 224. In certain embodiments, the catheter attachment 104 may be provided in the form of either a female Luer attachment or a male Luer attachment, and each of the pressure control device attachment 214 and the syringe attachment 224 may be provided in the form of either a female Luer attachment or a male Luer attachment. For example, the catheter attachment 104 may be provided in the form of a female Luer attachment, and each of the pressure control device attachment 214 and the syringe attachment 224 may be provided in the form of a mating male Luer attachment. It should be understood that other forms of attachments are also conceivable and can be used to form appropriate connections.

[0029] Further reference to Figure 4 shows an exemplary process 300 that may be performed using System 200. The illustrated blocks for the processes of this application are to be understood as illustrative only, and the blocks may be combined, divided, added, deleted, or rearranged in whole or in part unless expressly otherwise stated. Furthermore, although the blocks are illustrated in a relatively serial manner, it should be understood that two or more blocks may be performed simultaneously or in parallel with one another. Furthermore, although this specification describes Process 300 with specific reference to the system shown in Figures 1 and 2, it should be understood that Process 300 may be performed on a system having additional or alternative features.

[0030] Process 300 can be initiated with block 310, which generally includes generating negative gauge pressure in a chamber having an elastic device located therein, thereby compressing the elastic device. In certain embodiments, the chamber is formed within a cuff, with a discharge passage extending from the cuff to the discharge port. In the illustrated example, block 310 includes generating negative pressure in the chamber 122 of the cuff 120 using a negative pressure generating device such as a syringe 220. More specifically, block 310 includes connecting a syringe fitting 224 to a catheter fitting 104, which is typically a unidirectional normally closed check valve, which retracts a plunger 226, thereby generating negative gauge pressure in the chamber 122. It is also intended that block 310 include operating another form of negative pressure generating device to generate negative pressure in the chamber 122. For example, block 310 may include operating a pump to generate negative pressure in the chamber 122.

[0031] When negative pressure is generated in the chamber 122, the cuff 120 moves from an expanded state to a contracted state, thereby compressing the elastic device 130 with the walls of the cuff 120. As a result, the elastic device 130 transitions to a compressed state during the contraction of the cuff 120. In the compressed state, the elastic device 130 stores mechanical energy, which, when released, causes the elastic device 130 to expand to its expanded state, thereby expanding the cuff 120 as described herein.

[0032] In certain embodiments, process 300 generally includes block 320, which involves inserting the cuff into the patient's cavity. In the illustrated example, catheter 100 is a fecal catheter, and block 320 includes inserting the cuff 120 into the patient's rectum. Block 320 may also include inserting the cuff 120 into another cavity of the patient, for example, if catheter 100 is configured to be used as a urethral catheter or an airway catheter.

[0033] Process 300 further includes block 330, which generally includes connecting a first fitting that is in fluid communication with the chamber to a second fitting of the pressure control device. In certain embodiments, the pressure control device includes an inlet check valve that is in fluid communication with the second fitting and an outlet check valve that is in fluid communication with the second fitting. In the illustrated example, block 330 includes connecting the inlet / outlet fitting 104 of the catheter 100 to fitting 214 of the pressure control device 210, which includes an inlet check valve 216 and an outlet check valve 218. As described above, each of the check valves 216 and 218 is in fluid communication with the pressure control device fitting 214 via a fluid passage 213. In certain embodiments, such as including block 320, block 330 may be performed with the cuff 120 positioned in the patient's cavity.

[0034] Process 300 further includes block 340, which generally involves expanding an elastic device from a compressed state to an expanded state, thereby inflating the cuff and allowing fluid to flow into the chamber through an inlet check valve. In the illustrated example, block 340 includes allowing the elastic foam 332 to expand from a compressed state to an expanded state, thereby inflating the cuff 120. The cuff 120 remains deflated in blocks 310 and 320 despite the negative gauge pressure due to the one-way check valve properties of the first fixture 104. When the pressure control device 210 is connected to the first fixture 104 as described in block 330, the negative pressure in the cuff 120 is communicated to the pressure control device 210 through the expansion / contraction lumen 140. When the pressure difference across the inlet check valve 216 of the pressure control device 210 exceeds the cracking pressure of the inlet check valve 216 (which is normally closed), the inlet check valve 216 opens, thereby allowing air to flow into the chamber 122 to inflate the cuff 120. Between blocks 330 and 340, the cuff 120 is still under negative pressure, so the outlet check valve 218 remains closed. Fluid flow into the cuff 120 continues until the cuff pressure reaches the cracking pressure of the inlet check valve 216, beyond which the flow is automatically shut off. The use of the one-way inlet check valve 216 allows the internal cuff pressure to remain at negative pressure or at its limit atmospheric pressure, depending on the selected cracking pressure.

[0035] Process 300 may further include block 350, which generally includes at least partially compressing an elastic device in response to an externally applied force on the cuff, thereby at least partially deflating the cuff so that fluid flows out of the chamber through the outlet check valve. The externally applied force is, for example, the result of a patient's movement such as coughing, sneezing, or rectal contraction to defecate. In the illustrated example, block 350 involves at least partially compressing an elastic device 130 in response to an externally applied force on the cuff 120, thereby at least partially deflating the cuff 120 so that fluid flows out of the chamber 122 through the outlet check valve 218. Those skilled in the art will readily understand that when the external force is removed, the elastic device 130 expands again to reinflate the cuff 120 in a manner similar to that described with reference to block 340. The outflow of fluid from the cuff 120 reduces the pressure in the cuff. Since cuff 120 is under positive pressure within block 350, the inlet check valve 216 remains closed. Fluid outflow from cuff 120 continues until the cuff pressure reaches the cracking pressure of the outlet check valve 216, beyond which outflow automatically stops. By using a one-way outlet check valve, the pressure inside the cuff remains positive or at critical atmospheric pressure, depending on the selected cracking pressure.

[0036] Process 300 may further include block 360, which generally includes maintaining the pressure in the chamber within a selected pressure range having a minimum pressure and a maximum pressure. Block 360 may be performed, for example, by a pressure control device 210. In certain embodiments, the minimum pressure is above atmospheric pressure and not exceeding a pressure about 15 mmHg below atmospheric pressure. In certain embodiments, the minimum pressure is above a pressure of 8 mmHg below atmospheric pressure and not exceeding a pressure of 12 mmHg below atmospheric pressure. In certain embodiments, the minimum pressure is above atmospheric pressure and not exceeding a pressure about 10 mmHg below atmospheric pressure. In certain embodiments, the maximum pressure is not exceeding a pressure about 30 mmHg above atmospheric pressure. In certain embodiments, the maximum pressure is not exceeding a pressure about 20 mmHg above atmospheric pressure. In certain embodiments, the maximum pressure is not exceeding a pressure about 10 mmHg below atmospheric pressure. In certain embodiments, the maximum pressure is not exceeding a pressure of 4 to 6 mmHg above atmospheric pressure. In certain embodiments, block 360 may include maintaining the pressure in chamber 122 in a range from 10 mmHg below atmospheric pressure to 20 mmHg above atmospheric pressure. In certain embodiments, block 360 may include maintaining the pressure in chamber 122 in a range from 10 mmHg below atmospheric pressure to 10 mmHg above atmospheric pressure. In certain embodiments, block 360 may include maintaining the pressure in chamber 122 in a range from 10 mmHg below atmospheric pressure to 5 mmHg above atmospheric pressure. The ability to maintain negative pressure (i.e., below atmospheric pressure) while the cuff pressure is fully expanded is one difference between existing approaches of the disclosed subject matter and the particular embodiments. The external cuff pressure is the sum of the internal cuff pressure described above and the expansion force exerted by the resilient foam 130 on the cuff 120, and may be about 10 mmHg or less based on the type of foam selected according to Table 1. Accordingly, at least some embodiments of the present disclosure make it possible to set the maximum pressure of the cuff in contact with the mucous membrane tissue of the body cavity to a maximum pressure of about 30 mmHg higher than atmospheric pressure, preferably about 20 mmHg higher than atmospheric pressure, and more preferably about 10 mmHg higher than atmospheric pressure.

[0037] Those skilled in the art will readily understand that the pressure range maintained within the chamber 122 depends at least in part on the cracking pressures selected for the check valves 216, 218, and that check valves with appropriate cracking pressures can be selected to maintain a desired pressure range within the chamber 122. For example, in an embodiment where the minimum selected pressure within the chamber 122 is about 10 mmHg lower than atmospheric pressure, the inlet check valve 216 may be selected with a cracking pressure of about 10 mmHg (e.g., 10 mmHg ± 2 mmHg). Similarly, in an embodiment where the maximum selected pressure within the chamber 122 is about 20 mmHg higher than atmospheric pressure, the outlet check valve 218 may be selected with a cracking pressure of about 20 mmHg (e.g., 20 mmHg ± 4 mmHg). Certain embodiments may utilize an open vent to allow for rapid equilibrium with atmospheric pressure.

[0038] As can be understood from the above, the system 200, including the catheter 100 and the pressure management device 210, can accommodate patient movement while mitigating certain difficulties associated with conventional approaches, such as patient discomfort and the risk of pressure ulcers. For example, when the patient moves, the pressure increase in the chamber 122 acts on the outlet check valve 218, which opens, and the pressure drops rapidly. The use of one-way check valves 216, 218 can additionally or alternatively provide the advantages of rapid pressure adjustment and conformity to the rectal wall, which may correlate with improved sealing properties.

[0039] In certain embodiments, System 200 can provide better response times than conventional approaches. For example, some prior approaches required the use of a fluid transfer damper, which may be omitted in System 200 as described. In certain prior approaches requiring the use of a fluid transfer damper, the response time was generally in the range of 10 to 20 minutes. In other words, in such prior systems including a fluid transfer damper, it takes 10 to 20 minutes for the cuff 120 and elastic device 130 to expand and / or contract. Such response times may be improved by certain embodiments of System 200. For example, System 200 may be configured so that the cuff 120 transitions from an expanded state to a compressed state within 2 minutes, 1 minute, or 30 seconds. Such response times depend on many factors, including the compressibility or elasticity of the elastic device 130 and / or the cracking pressure of the outlet check valve 218. A person skilled in the art will find it easy to select these factors to provide the response times described above after reading this disclosure. Exemplary parameters that may help to reduce response times and / or improve patient comfort are shown here as Table 1. TIFF0007857961000001.tif34170

[0040] Specific embodiments relating to the present application relate to a system 200 having a catheter 100 and a pressure control device 210. The catheter 100 includes a cuff 120 defining a chamber 122, the cuff 120 having a contracted state and an expanded state; an elastic device 130 disposed within the chamber 122, having a compressed state corresponding to the contracted state and an expanded state corresponding to the expanded state, the elastic device 130 configured to expand from the compressed state to the expanded state as the cuff 120 transitions from the contracted state to the expanded state; a discharge passage 116 extending from the cuff 120 to a discharge port 113; and a first fitting 104 in fluid communication with the chamber 122. The pressure control device 210 includes a second fitting 214 releasably engaged with the first fitting 104, and at least one check valve 214 / 216 in fluid communication with the second fitting 214.

[0041] In a particular embodiment, at least one check valve includes an inlet check valve 216 that is in fluid communication with a second fitting 214, and an outlet check valve 218 that is in fluid communication with the second fitting 214.

[0042] In certain embodiments, the inlet check valve 216 has a first cracking pressure and is configured to allow fluid flow from the first pressure source to the chamber 122 when the pressure of the first pressure source exceeds the pressure in the chamber 122 by at least the first cracking pressure, and the outlet check valve 218 has a second cracking pressure and is configured to allow fluid flow from the chamber 122 to the second pressure source when the pressure in the chamber 122 exceeds the pressure of the second pressure source by at least the second cracking pressure.

[0043] In certain embodiments, the first pressure source and the second pressure source are both atmospheric pressure.

[0044] In certain embodiments, the pressure control device 210 does not have a fluid transfer damper.

[0045] In a particular embodiment, the elastic device 130 consists of a compressible foam 132.

[0046] In certain embodiments, each of the inlet check valve 216 and the outlet check valve 218 is composed of at least one of a duckbill valve, umbrella valve, disc valve, or diaphragm valve.

[0047] In certain embodiments, the outlet check valve 218 is configured to allow the cuff 120 to move from an inflated state to a deflated state within 2 minutes.

[0048] In certain embodiments, the outlet check valve 218 is configured to allow the cuff 120 to move from an inflated state to a deflated state within one minute.

[0049] In a particular embodiment, the pressure control device 210 is configured to maintain the pressure in the chamber 122 between a minimum pressure and a maximum pressure, where the minimum pressure is between atmospheric pressure and 12 mmHg below atmospheric pressure, and the maximum pressure is 30 mmHg above atmospheric pressure.

[0050] In certain embodiments, the maximum pressure is no more than 20 mmHg higher than atmospheric pressure.

[0051] In certain embodiments, the maximum pressure is 4 to 6 mmHg higher than atmospheric pressure.

[0052] A particular embodiment of this application relates to a method which generates a negative gauge pressure in a chamber 122 having an elastic device 130 310, thereby compressing the elastic device 130 into a compressed state, the chamber 122 being formed within a cuff 120, a discharge passage 116 extending from the cuff 120 to a discharge port 113, a first fitting 104 fluidly communicating with the chamber 122 connected to a second fitting 214 of a pressure control device 210 330, the pressure control device 210 having an inlet check valve fluidly communicating with the second fitting 214 The device includes a valve 216 and an outlet check valve 218 which is in fluid communication with a second fitting 214, and includes expanding the elastic device 130 from a compressed state to an expanded state 340, thereby inflating the cuff 120 and allowing fluid to flow into the chamber 122 through the inlet check valve 216, and at least partially compressing the elastic device 130 350 in response to an external force applied to the cuff 120, thereby at least partially crushing the cuff 120 so that fluid flows out of the chamber 122 through the outlet check valve 218.

[0053] In certain embodiments, the inlet check valve 216 allows the elastic device 130 to transition from a compressed state to an expanded state within two minutes.

[0054] In certain embodiments, the inlet check valve 216 allows the elastic device 130 to transition from a compressed state to an expanded state within one minute.

[0055] In certain embodiments, the outlet check valve 218 allows the elastic device 130 to transition from an expanded state to a compressed state within two minutes.

[0056] In certain embodiments, the outlet check valve 218 allows the elastic device 130 to transition from an expanded state to a compressed state within one minute.

[0057] In a particular embodiment, the pressure control device 210 maintains the pressure in the chamber 122 between a minimum pressure and a maximum pressure, where the minimum pressure is between atmospheric pressure and 12 mmHg below atmospheric pressure, and the maximum pressure is 20 mmHg above atmospheric pressure.

[0058] In certain embodiments, the maximum pressure is no more than 10 mmHg higher than atmospheric pressure.

[0059] In certain embodiments, the maximum pressure is 4-6 mmHg higher than atmospheric pressure.

[0060] In certain embodiments, the fluid is air.

[0061] A particular embodiment of the present application relates to a pressure control device 210 configured for use with a catheter 110 having a catheter attachment 104 that fluidly communicates with a chamber 122 defined by a cuff 120, wherein the pressure control device 210 comprises a fluid passage 213, an attachment 214 that fluidly communicates with the fluid passage 213 and is configured to engage with the catheter attachment 104 such that the fluid passage 213 communicates with the chamber 122 when the attachment 214 engages with the catheter attachment 104, and an inlet check valve 216 disposed between the fluid passage 213 and ambient air. The fluid passage includes an inlet check valve 216 having a first cracking pressure and configured to allow ambient air to flow into the fluid passage 213 when the ambient pressure exceeds the pressure in the fluid passage 213 by the first cracking pressure, and an outlet check valve 218 positioned between the fluid passage 213 and the ambient air, the outlet check valve 213 having a second cracking pressure and configured to allow ambient air to flow out of the fluid passage 213 when the pressure in the fluid passage 213 exceeds the ambient pressure by the second cracking pressure.

[0062] In certain embodiments, the pressure control device 210 further comprises a housing that defines a fluid passage 213, and a fitting 214, an inlet check valve 216, and an outlet check valve 218 are each attached to the housing.

[0063] In certain embodiments, the inlet check valve 216 and the outlet check valve 218 are each composed of one of the following: a duckbill valve, an umbrella valve, a disc valve, a diaphragm valve, or an open vent.

[0064] In certain embodiments, the first cracking pressure is between 0 mmHg and 15 mmHg.

[0065] In certain embodiments, the first cracking pressure is approximately 10 mmHg or less.

[0066] In certain embodiments, the second cracking pressure is approximately 30 mmHg or less.

[0067] In certain embodiments, the second cracking pressure is approximately 20 mmHg or less.

[0068] In certain embodiments, the second cracking pressure is approximately 10 mmHg or less.

[0069] In certain embodiments, the second cracking pressure is between 4 mmHg and 6 mmHg.

[0070] In a particular embodiment, the catheter attachment 104 consists of either a male Luer connector or a female Luer connector, and the attachment 214 consists of the other of either a male Luer connector or a female Luer connector.

[0071] A particular embodiment of the present application relates to a method of using a pressure control device, wherein the cuff 120 is in a retracted state, the catheter attachment 104 is fitted and engaged with the attachment 104, thereby fluidly communicating the fluid passage 213 with the chamber 122, a compressed elastic device 130 is placed inside the cuff 120, and in response to the ambient pressure which exceeds the pressure in the fluid passage 213 by a first cracking pressure or more, ambient air is allowed to flow into the chamber 122 via an inlet check valve 216, and in response to the pressure in the fluid passage 213 which exceeds the ambient pressure by a second cracking pressure or more, ambient air is allowed to flow out of the chamber 122 via an outlet check valve 218.

[0072] Although the present invention is illustrated and described in detail in the drawings and the foregoing description, these are illustrative and not intended to be restrictive. However, only preferred embodiments are illustrated and described, and it is understood that it is desirable that all changes and modifications within the spirit of the invention be protected.

[0073] The use of words such as preferred, preferable, desirable, or more preferred in the above description indicates that a feature described in this way may be more preferable, but nevertheless, it may not be necessary, and embodiments lacking the same may be contemplated within the scope of the invention, but it should be understood that the scope is defined by the claims that follow. When reading the claims, if words such as "one (a)," "one (an)," "at least one," or "at least a portion" are used, it is intended that the claims are not intended to be limited to only one item unless otherwise stated in the claims. If the words "at least a portion" and / or "a portion" are used, unless otherwise stated in the claims, that item may include a portion and / or all of the items.

Claims

1. A cuff defining a chamber, having both a contracted state and an expanded state. An elastic device disposed within the chamber, having a compressed state corresponding to the contracted state and an expanded state corresponding to the expanded state, wherein the cuff moves from the contracted state to the expanded state by expanding from the compressed state. A discharge passage extending from the cuff to the discharge port, A first mounting fixture that communicates fluid with the chamber. A catheter having, A second mounting fixture removably engaged with the first mounting fixture, and At least one check valve connected to the second mounting fixture via fluid communication A pressure control device having, The at least one check valve comprises an inlet check valve fluidly connected to the second fitting and an outlet check valve fluidly connected to the second fitting. The inlet check valve has a first cracking pressure and is configured to allow fluid flow from the first pressure source to the chamber when the pressure of the first pressure source exceeds the pressure in the chamber by at least the first cracking pressure. The outlet check valve has a second cracking pressure and is configured to allow fluid flow from the chamber to the second pressure source when the pressure in the chamber exceeds the pressure of the second pressure source by at least the second cracking pressure. The first pressure source and the second pressure source are, respectively, ambient air. system.

2. The inlet check valve and the outlet check valve are each composed of at least one of the following: a duckbill valve, an umbrella valve, a disc valve, or a diaphragm valve. The system according to claim 1.

3. The elastic device has an open-cell polyurethane foam having a density of 35 kg / m³ or more and 40 kg / m³ or less, and a 40% compression load deflection of 4 kPa or more and 5 kPa or less, and the check valve has a second cracking pressure of 30 mmHg or less. The system according to claim 1.

4. The elastic device has a compressible foam, The system according to claim 1.

5. The pressure control device is configured to maintain the pressure in the chamber between a minimum pressure and a maximum pressure. The aforementioned minimum pressure is between 12 mmHg lower than atmospheric pressure and atmospheric pressure. The aforementioned maximum pressure is no more than 20 mmHg higher than atmospheric pressure. The system according to claim 1.

6. The aforementioned maximum pressure is no more than 10 mmHg higher than atmospheric pressure. The system according to claim 5.

7. The pressure inside the chamber is a negative pressure that is between 12 mmHg lower than atmospheric pressure and atmospheric pressure. The system according to claim 5.

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