Patent ID: 12239464

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Increased abdominal pressure can cause many adverse conditions including diminishing the function of the intestines, liver, and blood vessels. Simply viewing or feeling the abdomen does not provide sufficient information or reading of health conditions.

It is recognized that urinary bladder pressure directly correlates to the intra-abdominal pressure. Although pressure readings can be determined by access to the esophagus or rectum, the bladder has been found to be the most accurate and the least invasive. In trauma or burn patients for example, time is critical and the less complicated the method for determining bladder pressure the better the clinical results.

It should be noted that the catheters of the present invention can be utilized for measuring other pressure in a patient and are not limited to intra-abdominal pressure. For example, they can be used to measure maternal uterine contraction measure by measuring bladder pressure. The catheters of the present invention can also be inserted into a variety of body cavities of the patient and can be used for monitoring pressure of various body regions.

These catheters can be used in various body cavities for measuring pressure and can be used without insertion of water or other fluid into the body cavity and thus have the numerous advantages associated with not requiring water as described herein.

Referring now to the drawings and particular embodiments of the present invention wherein like reference numerals identify similar structural features of the devices disclosed herein, there is illustrated inFIGS.1A-1Ba catheter of a first embodiment of the present invention. The catheter (device) is designated generally by reference numeral10and is configured for insertion into and positioning within the bladder of the patient for measuring intra-abdominal pressure, although it can be used to measure pressure of other body regions and inserted into other body regions. This measurement is to check if the intra-abdominal pressure exceeds a specified threshold since if such threshold is exceeded, there is a risk to the patient as discussed above and steps need to be taken to reduce the pressure such as draining additional fluid from the abdomen, opening the abdomen, etc.

As used herein, the term fluid encompasses a liquid or a gas.

The catheter10of the present invention can in some embodiments include an alarm or indicator to alert the user if pressure within the bladder, which correlates to pressure within the abdomen, rises to an unacceptable level, i.e., beyond a threshold or predetermined value (pressure). The indicator or alarm can be on the catheter or alternatively on an external device such as the monitor. The alarm can also be connected via wireless connection to a phone or remote device to alert the appropriate personnel. The indicator or alarm can alternatively or in addition be activated if a change in pressure measurement exceeds a specified rate over a specified period of time. This would alert the staff to an imminent risk prior to intra-abdominal pressure exceeding a certain value, e.g., 20 mm Hg, since due to this link, the relationship between intra-abdominal pressure and abdominal cavity volume is believed to be linear up to an intra-abdominal pressure of 12-15 mm Hg and increasing exponentially thereafter. The alarm system can include a comparator for comparing the measured pressure (and/or temperature) to a threshold (predetermined) value, and if such threshold is exceeded, an indicator, e.g., an alarm, is triggered to indicate to the hospital personnel the excessive pressure and/or temperature.

Turning now to details of the catheter10, which is also referred to herein as the device10, the catheter10of this embodiment has an elongated flexible shaft12having a lumen (channel)13extending within the shaft12and communicating at its distal region with balloon16to fluidly communicate with balloon16to inflate the balloon. Expandable balloon16is utilized for monitoring pressure and is also referred to herein as the “pressure balloon.” A fluid port15is positioned at a proximal region17of the catheter10for communication with an infusion source for infusion of fluid such as saline through the lumen13of shaft12and into the balloon16. The catheter10is shown inFIG.1Awith balloon16in the deflated condition (position) and inFIG.1Bwith the balloon16in the inflated condition (position). The shaft12can also include a second lumen (channel) and third lumen (channel) extending therein. In a preferred embodiment, the second lumen is the largest lumen and is configured for continuous drainage of bodily contents from the bladder and can be connected to a drainage bag for collection of urine. This lumen extends into lumen21at the catheter hub for drainage. The second lumen has a side opening22at a distal portion communicating with the bladder. The side opening22can be distal of the pressure balloon16or alternatively proximal of the balloon16such as between the pressure balloon16and the stabilizing balloon26as in the embodiment ofFIG.1B.

The third lumen terminates at its distal end within balloon26to fluidly communicate with balloon26to inflate the balloon26. The balloon26is inflatable to stabilize the catheter10to limit movement of the catheter10to keep it in place within the bladder and is also referred to herein as “the stabilizing balloon” or “retention balloon.” A fluid port28is positioned at a proximal region of the catheter10for communication with an infusion source for infusion of fluid through the third lumen and into the balloon26. The balloon26can be filled with fluid, e.g., liquid such as water or saline, or a gas, e.g., air. InFIG.1A, the balloon26is shown in the deflated condition and inFIG.1Bin the inflated condition.

The cross-sectional shapes of the lumens of catheter10and the other catheters disclosed herein can vary and can for example be circular, oval or other symmetrical or asymmetrical shapes in transverse cross section. As noted above, preferably the drainage lumen is the largest lumen but in alternate embodiments one or more of the other lumens could be larger than the drainage lumen.

The lumen13and space16awithin balloon16together form a closed fluid, chamber, i.e., the lumen13forming a fluid column. With the balloon16filled with saline or other liquid, pressure on the external wall of the balloon16will force the balloon16to deform inwardly, thereby compressing the liquid contained within the balloon space16aand within the lumen13.

A pressure sensor30can be located in a distal portion of the lumen14at the region of the balloon16and thus is positioned at the distal end of the fluid column. Thus, the pressure is sensed at the distal region as the sensor30detects change in fluid pressure in lumen13due to balloon deformation. Placement of the sensor30at a distal location provides a pressure reading closer to the source which in some embodiments/applications increases the accuracy because it reduces the risk of transmission issues by reducing the amount of interference which could occur due to water, air, clots, tissue, etc. if the transmission is down the lumen (fluid column).

In alternate embodiments, the pressure sensor is at a proximal region of the catheter and can in some embodiments be connected at the hub of the catheter or in a side port of the catheter or in a proximal portion of the lumen. It can be or positioned outside the patient at a proximal region of the catheter or part of a connector attached to the catheter hub.FIG.2illustrates the sensor in the connector connected to the catheter.

The sensor30in the embodiment ofFIGS.1A and1Bis positioned within lumen13adjacent balloon16, although alternatively it can be positioned within the balloon. The wire(s)32are shown extending through lumen13, the sensor30and wire(s)32being of sufficiently small size so as not to interfere with liquid flow though lumen13. The sensor30measures pressure of the bladder. The sensor30converts the variation in pressure to an electrical signal for transmission to an external monitor. The pressure sensor can also include a temperature sensor, or alternatively another sensor for sensing temperature could be provided, to measure core temperature of the body as seen inside the bladder. Transmission wire(s)34of the temperature sensor extend adjacent wire32through lumen13and terminate external of the catheter10for connection to an external monitor. The transducer can be wired directly to the monitor or alternatively wired to a converter external of the catheter for converting the signal received by the transducer and transmitting a signal to the monitor, e.g., a bedside monitor, to display the pressure readings. A cable with a monitor connector like cable50ofFIG.2Aextends from the catheter10to a pressure monitor. The pressure readings can be displayed in quantitative form, graphical form or other displays to provide an indicator to the clinician of the bladder pressure. The monitor, or a separate monitor, can also display the temperature readings from sensor30. Alternatively, the sensor/transducer can be connected to the monitor via a Bluetooth wireless connection.

Wires32and34can extend though lumen13and exit side port15for connection to a converter or monitor or alternatively can be inserted through the lumen13, piercing the wall to enter the lumen distal of the side port.

The lumen13and space16awithin balloon16together form a closed fluid chamber, i.e., the lumen13forming a fluid column. With the balloon16filled (either fully filled or partially filled, although partially filled is preferred) with fluid such as saline, pressure on the external wall of the balloon will force the balloon to deform inwardly, thereby compressing the fluid contained within the balloon space16aand within the lumen13. The pressure sensor30, located in a distal portion or alternatively a proximal portion of the catheter10, detects change in fluid pressure in lumen13due to balloon deformation.

The pressure measurement occurs about a more circumferential area of the balloon16providing a pressure reading of a region greater than a point pressure sensor reading. Also, average pressure over an area of the bladder wall can be computed. Thus, the area reading gleans information on pressure over more of the bladder wall. Stated another way, the balloon has a relatively large surface area with multiple reference points to contribute to average pressure readings of the surface around it by the sensor.

The fluid is inserted through the side port15which communicates with lumen13. The side port15at the catheter hub includes a membrane or filter19designed to enable the escape of air but prevent the escape of fluid. This enables removal of air to ensure filling of the pressure balloon16. That is, when the fluid is inserted through the catheter lumen13into the balloon16, air is forced out of the balloon16and proximally within the lumen of the catheter, through exit port and exiting the membrane19. This provides a way to remove the air for accurate pressure readings without having to pull a vacuum. The membrane19can for example be a 0.2 micron filter with pores sized to enable outflow of air, but prevent outflow of saline or other liquid. In this manner, the saline remains in the catheter in a closed system and the air is forced out so the pressure can be accurately measured since the presence of air could create pressure reading inaccuracies. For example, air in the system could create an air lock and affect pressure reading. The membrane19is shown in the side port15of the catheter, however, it is also contemplated that it can be positioned in other regions of the catheter which is discussed in more detail below. The membrane can be composed of PTFE or other materials. A valve can be provided in some embodiments to provide two lines communicating with the balloon.

The air escape can be through an opening in the drainage lumen, covered with the membrane, which can communicate with the interior space of the pressure balloon, so air escapes through the drainage lumen. Alternatively, the air escape can be through another lumen of the catheter with an opening in the lumen communicating with the interior space of the balloon.

The balloon16, as well as other balloons disclosed herein, can be composed of impermeable material, or in alternative embodiments, a permeable or semi-permeable material with an impermeable coating, depending on the material used and the fluid utilized for inflation, to prevent escape of air through the wall of the balloon16. The fluid column is sealed at the distal end to prevent escape of air through the distal end.

The balloon16can be fully inflated and can press against the wall of the cavity in use. In some embodiments, depending on the material used and the fluid used for inflation, the balloon can be partially inflated to provide more compliancy to prevent the balloon from introducing artifact into the pressure reading which would diminish its accuracy.

Note in this embodiment, the stabilizing balloon26is positioned proximal of the pressure balloon16. Also, in this embodiment, the stabilizing balloon26is larger than the pressure balloon16. By way of example, the stabilizing balloon26can have a fully expanded diameter of about 23 mm and the pressure balloon16can have a fully expanded diameter of about 15 mm, although other dimensions or diameters for these balloons are also contemplated. By way of example, the stabilizing balloon26can have a capacity of about 10 cc (10 ml) of air, although other sizes/volumes are also contemplated. Note these sizes/volumes for both balloons are provided by way of example and other sizes are also contemplated. Alternatively, the stabilizing balloon can be the same size or smaller than the pressure balloon. Various shapes of the balloons are also contemplated.

Additionally, although the stabilizing balloon26is positioned proximal of the balloon16, it is also contemplated that the balloon26be positioned distal of balloon16. The axial spacing of the balloons16,26enable the stabilizing balloon26to engage the bladder wall (or other cavity wall) to provide a sufficient radial force thereon for securing/mounting the catheter within the bladder without interfering with the function of balloon16.

Note that although only one sensor is shown in, it is also contemplated that multiple sensors can be provided. Also, note that the sensor30is positioned in lumen13at a mid-portion of the balloon, i.e., just proximal where the opening in lumen13communicates with the interior16aof the balloon16. It is also contemplated that the sensor can be placed at another portion within the lumen13, e.g., a more proximal portion, with respect to the lumen opening for the balloon. Also, the lumen opening for the balloon need not be at the mid portion of the balloon and can be at other regions of the balloon to communicate with the interior space16a. Note if multiple sensors are provided, they can be positioned at various locations within the lumen13.

As shown, the sensor30and its transmission wires are located in the same lumen13also used for initial inflation for balloon16and for the column. This minimizes the overall transverse cross-section (e.g., diameter) of the catheter10by minimizing the number of lumens since additional lumens require additional wall space of the catheter. However, it is also contemplated in an alternate embodiment the sensor is in a dedicated lumen separate from the inflation lumen13. This can be useful if a larger sensor or additional wires are utilized which would restrict the inflation lumen if provided therein. This is also useful if a specific sized lumen for the sensor and wires is desired to be different than the sized lumen for the fluid column. In such embodiments, the catheter would have four lumens: 1) a lumen for drainage of the bladder which has a side opening at a distal end to communicate with the bladder; 2) a lumen for filling the pressure balloon; 3) a lumen for filling the stabilizing balloon; and 4) a lumen in which sensor30and its transmission wires32and temperature sensor wires34are contained. Note in some embodiments, separate lumens could be provided for the wires32and wires34. Also, in some embodiments, a stabilizing balloon is not provided so the catheter can have one less lumen.

Turning now to the use of the catheter10, the catheter10is inserted into the bladder. The stabilizing balloon26is inflated to secure the catheter10in place during the procedure by insertion of a fluid (liquid or gas) through side port28which is in fluid communication with the lumen communicating with balloon26. The balloon16is inflated by insertion of saline or other liquid via a syringe through port15which is in fluid communication with lumen13. Insertion/injection of saline forces the air out of the balloon16and proximally through the catheter10to exit through the membrane19. The balloon16is sealed so that saline inserted through lumen13and into balloon16cannot escape through balloon16. Thus, a closed chamber for the saline is formed comprising the internal space16aof the balloon16and the internal lumen13communicating with the internal space16aof balloon16. With the balloon16inflated, pressure monitoring can commence. When external pressure is applied to an outer surface16bof the balloon16, caused by outward abdominal pressure which applies pressure to the bladder wall and thus against the wall of balloon16, the liquid within the chamber is compressed. The sensor30at the distal end of lumen13(or in other regions of the catheter or attached to the catheter hub in alternate embodiments as described herein) provides continuous pressure readings, converted to an electrical signal by the transducer, and then electrically communicates through wire(s)32extending through lumen13, exiting through the proximal side port15and connected to an external monitor. Note the wire can terminate at the proximal end in a plug in connector which can be connected directly to the monitor or alternatively plugged into a converter to convert the signals from the transducer in the embodiments wherein the converter is interposed between the wires and monitor to provide the aforedescribed graphic display. Although, the system is capable of continuous pressure and temperature monitoring, it can also be adapted if desired for periodic monitoring so the pressure and/or temperature readings can be taken at intervals or on demand by the clinician.

In the embodiments wherein an indicator is provided, if the measured pressure exceeds a threshold value, and/or a change in pressure measurement exceeds a specific rate over a specific time period, the indicator would alert the clinician, e.g., via a visual indication or an audible indication that the threshold is exceeded. The indicator in some embodiments can include an audible or visual alarm. In the embodiments having an indicator, the indicator can be provided on a proximal end of the catheter which extends out of the patient or the indicator can be part of an external component such as the monitor or a separate alarm system. A visual, audible, or other indicator can likewise be provided in any of the other embodiments disclosed herein to indicate if the measured temperature exceeds a predetermined value, and such indicator can include an alarm and can be part of the catheter or a separate component.

As discussed above, the pressure balloons disclosed herein have a large circumferential area (and large volume) to provide multiple reference points for pressure readings and to provide an average pressure to enable more accurate readings. In some embodiments, a pear shaped larger outer balloon is provided such as in the embodiment ofFIG.2A. The covers more surface area for pressure readings. The pear shape could in certain applications decrease the risk of obstructing the ureter and provide more tactile continuity of the balloon to the bladder wall giving a better transmission of abdominal pressure to the internal sensor. This pear shape in some applications is designed to conform to the shape of the bladder. The pressure balloon can be shaped such that a distal region has an outer transverse cross-sectional dimension, e.g., diameter, greater than an outer transverse cross-sectional dimension, e.g., diameter, of the proximal region such as in the embodiments ofFIGS.2and3. The pressure balloons of the embodiments herein can be symmetrically or asymmetrically shaped.

FIGS.3and4illustrate an alternate embodiment of the pressure and stabilizing balloon. The stabilizing balloon74of catheter70is proximal of the pressure balloon72and has an oval like shape. The pressure balloon72is shown extending beyond the tip76of the catheter70. Tip76has a proximal extension76apositioned within the lumen77. The catheter70has a filter or membrane78adjacent balloon72so that when balloon72is inflated with saline or other liquid, air is forced out of balloon72and travels through the catheter lumen77and through the membrane78to exit the catheter at a proximal end. A separate lumen75inflates pressure balloon72. The pores of membrane78are dimensioned to allow escape of air but prevent escape of the inflation liquid. The membrane78is shown adjacent the pressure balloon72but can be positioned in other regions of the catheter70, i.e. in the various locations disclosed herein, e.g., in a proximal portion of the catheter, in the catheter hub, etc. As in the embodiment ofFIG.1A, in the expanded position of the balloon72, pressure on the wall of balloon72deforms the outer wall of the balloon72and compresses the liquid therein to provide pressure readings as disclosed herein. A drainage hole79can be provided between the stabilizing balloon74and pressure balloon72for drainage through lumen71. A separate lumen is used to inflate the stabilizing balloon74.

In the embodiment ofFIG.2, the pressure sensor/transducer are external to catheter40and mounted to port42at the proximal end44of catheter40. More specifically, a transducer hub or housing46contains the sensor/transducer and is mounted to the angled side port42. The hub46can be mounted over the port42and can be locked or secured thereto such as by a friction fit, snap fit, threaded attachment, a latch, etc. Thus, when external pressure is applied to an outer surface45aof the balloon45, caused by outward abdominal pressure which applies pressure to the bladder wall and thus against the wall of balloon45, the fluid within the chamber (formed by the internal space of the balloon45and the lumen) is compressed. The sensor in the hub46attached to the catheter port provides continuous pressure readings, and then electrically communicates through cable50to an external monitor. Port41is for fluid insertion to inflate the stabilizing balloon47.

The pressure balloons of the various embodiments can by way of example be made of urethane, although other materials are also contemplated such as silicone or EVA.

A temperature sensor, such as a thermocouple, is positioned within the catheter40at a distal end to measure core body temperature in the same manner as inFIG.1A, with. one or more wires extending from the sensor through the lumen. A connector, e.g., a male connector, is at the proximal terminal end of the wire and the transducer hub46includes a connector which receives the connector of the wire. When the hub46is mounted to port42of catheter40, the connector of the wire is automatically connected to a connector carried by or within the hub46which is in communication with a temperature monitor, such as by cable50. Other types of connectors/connections are also contemplated. Temperature readings can be taken at intervals or on demand by the clinician. The temperature monitor can be separate from the pressure display monitor or alternatively integrated into one monitor. Cable50can connect to the temperature monitor as well (directly or via a converter) or a separate cable extending from the hub46could be provided for connection to the temperature monitor.

FIGS.5A and5B,6and7illustrate alternate embodiments of the membrane for allowing the escape of air during filling of the balloon with saline or other fluid. Note these embodiments can have a stabilizing balloon in addition to the pressure balloon. In the embodiments ofFIGS.5A and5B, catheter60has a filter/membrane62at a distal region of lumen64adjacent pressure balloon66. Saline is inserted through lumen68which communicates with pressure balloon66. As the balloon is being filled, the air is forced out of the balloon66, passing through membrane62and traveling proximally in lumen64to exit in a vent in or adjacent a hub of the catheter at the proximal end. The membrane62has pores dimensioned to allow the escape of air but prevent the escape of saline so that during inflating the balloon, the saline cannot escape from the balloon66into lumen64through membrane62.

In the embodiment ofFIG.6, catheter80has a membrane82positioned within a lumen84at the proximal end of the catheter. Liquid, e.g. saline, is inserted through port85to flow through lumen86to inflate the pressure balloon87which forces out air from the balloon87which flows through lumen84(which is in communication with balloon87) to exit through membrane82. The catheter80can include a valve89which can be turned on to allow passage of air through the membrane82and closed to prevent passage of air. The liquid is prevented from flowing out of the catheter when the valve is closed as well as when the valve is open since it cannot pass through the pores of the membrane82. Note a valve can be provided in the catheters having the membrane placed in other regions of the catheter.

In the embodiment ofFIG.7, catheter90includes a T-connector92with an opening94for liquid, e.g., saline or water insertion, and opposing opening (vent port)96for escape of air. At opening94, a luer or other connector enabling connection of a syringe or other device to fill the pressure balloon93is provided. The liquid inflates the pressure balloon93and forces the air out through exit opening96. Membrane98is positioned within the T-fitting92to enable passage/escape of air and prevent passage of the other liquid, e.g. saline or water. InFIG.7, one of the catheter lumens has a tube97positioned therein. This tube97has an opening communicating with the interior space of the pressure balloon93and extends back to the membrane98. In alternate embodiments, the tube is not provided and air flows through the lumen for escape rather than through the tube. The balloon inflation lumen (channel) can be filled until water comes to the end to fill the channel which would force the air out of the system through the membrane98. The membrane can alternatively be located in other portions of the catheter. The tube communicating with the membrane can be provided in the catheters of the other embodiments disclosed herein.

The membrane for passage of air can be provided at various regions of the catheter, e.g., adjacent the balloon, at the catheter hub, at a proximal region of the catheter, etc. Also, the membrane can be positioned within the drainage lumen or in a separate lumen which communicates with the interior space of the balloon. It can also be provided in a tube which extends through a lumen of the catheter and has an opening in communication with the interior space of the balloon. In some embodiments, the pressure sensor can be positioned in a chamber and the chamber can have air passage, e.g., a membrane, filter, and valve. The sensor can be connected to the catheter, and the air can be removed at the interface of the catheter and the sensor. A purge valve can be provided on the connector. The vent can be below (distally) but before the side ports of the catheter.

The membrane can also be utilized in a catheter with multiple pressure balloons as in the embodiment ofFIG.13. Catheter100has first and second pressure balloons102,104extending radially on opposing sides of the catheter, i.e., positioned side by side. A plurality of drainage holes106a,106b.106care positioned in a side wall of the catheter100between the balloons102,104. A membrane is provided in catheter100either adjacent the balloon102,104or at another region of the catheter100to enable escape of air from the balloon102,104as they are inflated as described in the foregoing embodiments. In some embodiments, separate membranes108,110can be provided for the lumens communicating with balloons102,104, respectively, for air escape. The balloons102,104are filled with liquid such as saline or water and form a liquid chamber or column as described above. Pressure can be determined by pressure differentials between the two balloons or by reading both pressure balloons and taking an average of the two readings.

In the embodiment ofFIGS.8-12, the pressure balloon112extends distally of the catheter110in the non-expanded position to shield the tip of the catheter. As shown, catheter110has an outer pressure balloon112which during insertion is deflated and partially contained within the shaft114. However, in this insertion position, a distal region116of balloon112extends forward of the distal end of the catheter110. This shape creates a nose cone at the tip. The protruding pressure balloon112is preferably made of polyurethane, although other materials can be utilized. When the balloon is inflated, it slides/pops out of the distal end of the catheter shaft114. Thus, as it opens up, it elongates out of the catheter body and the proximal portion is a smaller diameter so the distal opening115of catheter110becomes open for drainage. The catheter is shown inFIG.12with the balloon112illustrated in phantom lines in the expanded position. Additional drainage openings121can be provided in a side wall of the catheter110. A stabilizing balloon120can be positioned proximal of the pressure balloon112. The stabilizing balloon120can be made of silicon, although other materials are also contemplated. The catheter in some embodiments can be made of polyurethane, although other materials are also contemplated. The catheter hub has port122for fluid infusion to inflate/expand the pressure balloon112, port124for drainage, and port126for fluid insertion to inflate/expand the stabilizing balloon120. Temperature sensor (thermistor)129can be positioned adjacent or within the pressure balloon112. Temperature sensor wires can extend through port128.

Pressure balloon112can be filled with gas such as air to form a closed gas chamber for pressure monitoring. Alternatively, it can be filled with a liquid such as saline in which case the catheter (or connector) can include a membrane to allow escape of air as the pressure balloon is filled as in the embodiments described above.

As noted herein, the catheters of the present invention can be utilized for measuring other pressure in a patient and are not limited to intra-abdominal pressure nor limited to measuring bladder pressure.

In the catheters disclosed herein, thermistor can be placed adjacent the drainage opening for temperature readings, and the thermistor wire can extend through a lumen of the catheter, e.g., the drainage lumen, the pressure lumen or a separate lumen, for electrical connection to a temperature monitor.

The balloons of the catheters disclosed herein could include a coating such a parylene to change the modulus of the balloon. That is, such coating could stiffen the balloon so it is not to continuously expand under pressure, which could cause a reduced pressure reading. The coating can also cover all or part of the catheter which could add lubricity.

The balloons disclosed in the various embodiments can be coated to reduce their permeability. That is, to prevent escape of fluid, the balloons can be made of an impermeable material and/or the balloons can be made of a permeable material and coated with an impermeable material.

As noted herein, the catheters of the present invention can be utilized for measuring other pressure in a patient and are not limited to intra-abdominal pressure nor limited to measuring bladder pressure. Thus, the structure can be used for example with catheters to measure maternal uterine contraction pressure by measuring bladder pressure as in co-pending application Ser. No. 15/949,022, filed Apr. 9, 2018 (Publication No. 2018/0344250), the entire contents of which are incorporated herein by reference, and with catheters to measure the intrauterine pressure in the uterus and the fallopian tubes during HSG, SHG, HyCoSy, or SIS procedures or other procedures, as in co-pending application Ser. No. 15/978,072, filed May 11, 2018 (Publication No. 2018/0344183), the entire contents of which are incorporated herein by reference.

In embodiments disclosed herein, a digital pressure sensor can be used instead of an analog sensor.

The wire connector of the foregoing embodiments can plug into the openings of a connector positioned on or in the hub. The wire connector can be internal of the hub with an opening in the wall of the hub to enable access for the wire connector. Also note that alternatively the wire can include a female connector and the hub can have a male connector. Other types of connectors/connections are also contemplated.

In some embodiments the catheters disclosed herein can include a pulse oximetry sensor to measure oxygen saturation in the urethral or bladder tissue. The sensor can be located either proximal or distal to the pressure balloon and/or either proximal or distal to the stabilizing balloon. It could also alternatively be mounted within one of the balloons.

It is also contemplated that in some embodiments a backup system can be provided to determine pressure. The backup system can provide a double check of pressure readings to enhance accuracy. Such backup system can be used with any of the embodiments disclosed herein to provide a second pressure reading system. One example of such backup system is providing a pressure transducer/pressure sensor within the catheter lumen communicating with the pressure balloon, forming a “first system”, plus a pressure transducer/pressure sensor at another region of the catheter or external of the catheter forming a “second system”. The pressure sensors are electrically connected to a monitor which provides a graphic display of pressure readings. The catheter can also include a temperature sensor either as part of the pressure sensor adjacent the distal portion of the catheter or a separate component that can be positioned in the lumen.

In use of such backup system, the sensor provides continuous pressure readings, and such pressure readings can be confirmed by the proximal sensor. Such pressure readings can be performed continuously (along with continuous temperature monitoring) or alternatively can also be adapted if desired for periodic monitoring so the pressure and/or temperature readings can be taken at intervals or on demand by the clinician. Thus, pressure readings at a proximal end plus microtip pressure readings at the distal end are provided. The sensors can electrically communicate with an external monitor to display both pressure readings from the sensors, or alternatively, if the pressure readings are different, they can be averaged to display a single measurement. Other displays of information can be provided to display the information from the two sensors.

The sensors disclosed herein can be microtip sensors within the fluid lumen or balloon. In alternative embodiments, fiber optic sensors within the fluid lumen or balloon can by utilized to transmit circumferential/area pressure. The pressure transducers can be housed within the catheter or alternatively external to the catheter. Additionally, core temperature sensors can be part of the pressure sensor or a separate axially spaced component.

The multi-lumen catheters are easily inserted into the bladder in the same manner as standard bladder drainage catheters and enable continuous drainage of urine while continuously recording IAP without interrupting urine flow and without requiring retrograde filling of the bladder with water. The catheters also have a balloon providing a large reservoir (large capacity) and large circumferential area/interface for obtaining more information from the bladder over multiple reference points (rather than a single point sensor) that provides an average pressure to provide a more accurate assessment of the surrounding environment as pressure measurement is not limited to one side of the bladder but can determine measurements on the opposing side as well. The balloon can have a sufficiently large circumferential area so that it is in contact with the bladder wall, and in some embodiments, could distend the bladder wall, thus enabling pressure measurement without insertion of fluid into the bladder. When used in other body cavities for other pressure measurements, the pressure balloon of the multi-lumen or single lumen catheters disclosed herein can be of sufficiently large to contact or in some embodiments, distend the cavity wall, thus enabling pressure measurement without insertion of fluid into the cavity.

The catheters in some embodiments can be connected to a bedside monitor through either a wire or blue-tooth wireless connection. The system can also in some embodiments include an indicator or alarm system to alert the staff at the site as well as remote staff through wired or wireless connections to external apparatus, e.g., hand held phones or remote monitors.

As noted above, an alarm or indicator can be provided in some embodiments to alert the staff. The indicator can be a visual indicator such as a light, LED, color change, etc. Alternatively, or additionally, the indicator can be an audible indicator which emits some type of sound or alarm to alert the staff. The indicator can be at the proximal region of the catheter or at other portions of the catheter, e.g., at a distal end portion, where known imaging techniques would enable the user to discern when the indicator is turned on. It is also contemplated that in addition to providing an alert to the user in some embodiments, the pressure monitoring system can be tied into a system to directly reduce abdominal pressure so that if the pressure exceeds a threshold level (value), the abdominal pressure can automatically be reduced. In such systems, an indicator can be provided on the proximal portion of the catheter, e.g., at a proximal end outside the patient's body, or separate from the catheter. The sensor can be in communication with the indicator, either via connecting wires extending through a lumen of the catheter or a wireless connection. The sensor can be part of a system that includes a comparator so that a comparison of the measured pressure to a predetermined threshold pressure value is performed and a signal is sent to the indicator to activate (actuate) the indicator if the measured pressure exceeds the threshold pressure to alert the clinician or staff that pressure within the abdomen is too high and a signal is also sent to a device or system to automatically actuate the device or system to reduce the abdominal pressure. If the measured temperature is below the threshold, the indicator is not activated. A similar system can be used for temperature measurement and indication.

It is also contemplated that a micro-air charged sensor could be provided in the retention (stabilizing) balloon.

It is also contemplated that microtip sensors and/or fiber optic sensors can be utilized to measure pressure, and these sensors can be utilized instead of or in addition to the fluid pressure readings utilizing the aforedescribed balloon(s) for measuring pressure.

Pulse oximeters for measuring oxygen levels (oxygen saturation) in the urethral and/or bladder tissue could also be provided. In some embodiments, the pulse oximetry sensors can be positioned on the catheter proximal to the retention balloon. Alternatively, the sensors can be positioned within the retention balloon, on the catheter distal to the pressure balloon or on other regions of the catheter. Another channel in the catheter can be provided for the sensor and its connector to external devices, e.g. readers.

The catheters disclosed herein are designed for insertion into the bladder. However, it is also contemplated that they can be adapted for insertion into the rectum, colostomy pouch, stomach, supra-pubic bladder drain, or other orifice directly connected with the abdominal cavity. They can also be inserted into other areas connected with other cavities. Uses include by way of example, cardiac use, labor and delivery use, rectal placement for abdominal cavity, use for gastric pressure, esophageal motility, endocranial pressures ERCP, gall bladder, etc.

Although the apparatus and methods of the subject invention have been described with respect to preferred embodiments, those skilled in the art will readily appreciate that changes and modifications may be made thereto without departing from the spirit and scope of the present invention as defined by the appended claims.