Patent Application
20240382660
The present disclosure relates generally to medical fluid treatments and in particular to dialysis fluid treatments.
Due to various causes, a person's renal system can fail. Renal failure produces several physiological derangements. It is no longer possible to balance water and minerals or to excrete daily metabolic load. Toxic end products of metabolism, such as, urea, creatinine, uric acid and others, may accumulate in a patient's blood and tissue.
Reduced kidney function and, above all, kidney failure is treated with dialysis. Dialysis removes waste, toxins and excess water from the body that normal functioning kidneys would otherwise remove. Dialysis treatment for replacement of kidney functions is critical to many people because the treatment is lifesaving.
One type of kidney failure therapy is Hemodialysis (“HD”), which in general uses diffusion to remove waste products from a patient's blood. A diffusive gradient occurs across the semi-permeable dialyzer between the blood and an electrolyte solution called dialysate or dialysis fluid to cause diffusion.
Hemofiltration (“HF”) is an alternative renal replacement therapy that relies on a convective transport of toxins from the patient's blood. HF is accomplished by adding substitution or replacement fluid to the extracorporeal circuit during treatment. The substitution fluid and the fluid accumulated by the patient in between treatments is ultrafiltered over the course of the HF treatment, providing a convective transport mechanism that is particularly beneficial in removing middle and large molecules.
Hemodiafiltration (“HDF”) is a treatment modality that combines convective and diffusive clearances. HDF uses dialysis fluid flowing through a dialyzer, similar to standard hemodialysis, to provide diffusive clearance. In addition, substitution solution is provided directly to the extracorporeal circuit, providing convective clearance.
Most HD, HF, and HDF treatments occur in centers. A trend towards home hemodialysis (“HHD”) exists today in part because HHD can be performed daily, offering therapeutic benefits over in-center hemodialysis treatments, which occur typically bi- or tri-weekly. Studies have shown that more frequent treatments remove more toxins and waste products and render less interdialytic fluid overload than a patient receiving less frequent but perhaps longer treatments. A patient receiving more frequent treatments does not experience as much of a down cycle (swings in fluids and toxins) as does an in-center patient, who has built-up two or three days' worth of toxins prior to a treatment. In certain areas, the closest dialysis center can be many miles from the patient's home, causing door-to-door treatment time to consume a large portion of the day. Treatments in centers close to the patient's home may also consume a large portion of the patient's day. HHD can take place overnight or during the day while the patient relaxes, works or is otherwise productive.
Another type of kidney failure therapy is peritoneal dialysis (“PD”), which infuses a dialysis solution, also called dialysis fluid, into a patient's peritoneal chamber via a catheter. The dialysis fluid is in contact with the peritoneal membrane in the patient's peritoneal chamber. Waste, toxins and excess water pass from the patient's bloodstream, through the capillaries in the peritoneal membrane, and into the dialysis fluid due to diffusion and osmosis, i.e., an osmotic gradient occurs across the membrane. An osmotic agent in the PD dialysis fluid provides the osmotic gradient. Used or spent dialysis fluid is drained from the patient, removing waste, toxins and excess water from the patient. This cycle is repeated, e.g., multiple times.
There are various types of peritoneal dialysis therapies, including continuous ambulatory peritoneal dialysis (“CAPD”), automated peritoneal dialysis (“APD”), tidal flow dialysis and continuous flow peritoneal dialysis (“CFPD”). CAPD is a manual dialysis treatment. Here, the patient manually connects an implanted catheter to a drain to allow used or spent dialysis fluid to drain from the peritoneal chamber. The patient then switches fluid communication so that the patient catheter communicates with a bag of fresh dialysis fluid to infuse the fresh dialysis fluid through the catheter and into the patient. The patient disconnects the catheter from the fresh dialysis fluid bag and allows the dialysis fluid to dwell within the peritoneal chamber, wherein the transfer of waste, toxins and excess water takes place. After a dwell period, the patient repeats the manual dialysis procedure, for example, four times per day. Manual peritoneal dialysis requires a significant amount of time and effort from the patient, leaving ample room for improvement.
Automated peritoneal dialysis (“APD”) is similar to CAPD in that the dialysis treatment includes drain, fill and dwell cycles. APD machines, however, perform the cycles automatically, typically while the patient sleeps. APD machines free patients from having to manually perform the treatment cycles and from having to transport supplies during the day. APD machines connect fluidly to an implanted catheter, to a source or bag of fresh dialysis fluid and to a fluid drain. APD machines pump fresh dialysis fluid from a dialysis fluid source, through the catheter and into the patient's peritoneal chamber. APD machines also allow for the dialysis fluid to dwell within the chamber and for the transfer of waste, toxins and excess water to take place. The source may include multiple liters of dialysis fluid including several solution bags.
APD machines pump used or spent dialysate from the peritoneal chamber, though the catheter, and to the drain. As with the manual process, several drain, fill and dwell cycles occur during dialysis. A “last fill” may occur at the end of the APD treatment. The last fill fluid may remain in the peritoneal chamber of the patient until the start of the next treatment, or may be manually emptied at some point during the day.
In any of the above modalities using an automated machine, the automated machine operates typically with a disposable set, which is discarded after a single use. Depending upon the complexity of the disposable set, the cost of using one set per day may become significant. Also, daily disposables require space for storage, which can become a nuisance for home owners and businesses. Moreover, daily disposable replacement requires daily setup time and effort by the patient or caregiver at home or at a clinic.
There is also a need for APD devices to be portable so that a patient may bring his or her device on vacation or for work travel.
For each of the above reasons, it is desirable to provide a relatively simple, compact APD machine, which operates a simple and cost effective disposable set.
The present disclosure relates to an automated peritoneal dialysis (“APD”) machine or cycler, which provides a chamber sized to hold all of the fresh and used peritoneal dialysis (“PD”) fluid, albeit at different times, used over the course of a treatment. A weigh scale may be positioned to weigh the chamber and any of the fresh of used PD fluid provided initially, any fresh PD fluid that enters during treatment, and any used PD fluid that leaves during treatment. In this manner, the weigh scale is able to monitor over an entire treatment, including an initial patient drain if needed, and output weight signals to a control unit so that fill and drain volumes may be monitored and known and an overall amount of patient ultrafiltration (“UF”) at the end of treatment may be determined.
The chamber is also provided with a fluid heater, such as an electrical plate heater, which heats the fresh PD fluid provided in each PD fluid container or bag loaded into the chamber. The PD fluid containers or bags may be loaded on top of each other or side-by-side within the chamber as needed for proper heating. The PD fluid containers or bags may hold multiple patient fill volume's worth of fluid and a last fill container of icodextrin may be provided. The PD fluid containers or bags may hold different formulations, so that different patient fills may contain different dextrose or glucose levels. The different formulations may also be mixed for a single patient fill to provide a PD formulation optimized for the patient.
The PD fluid containers are connected to and fluidly communicate with an initially dry portion of the disposable set, which includes a common line connecting to each of the PD fluid container supply lines, a pumping (e.g., peristaltic pumping) line, a patient line and in one embodiment a terminal or final drain line. The disposable set may also include a drain container located within the chamber, which enables used dialysis fluid to be removed from the patient, delivered temporarily to the drain container for weighing, and then removed from the drain container to a house drain or final or terminal drain container, which may be performed during a patient dwell.
In an embodiment, the supply lines of the dry portion of the disposable set connect to container lines extending from fresh PD fluid supply containers. The connections may be made along a side, surface or wall of the chamber. In another embodiment, the supply lines of the dry portion of the disposable set extend through holes or slots in the side, surface or wall of the chamber for direct connection to the fresh PD fluid supply containers.
In another embodiment, a separate drain container is not provided and instead the PD fluid containers or bags accept used dialysis fluid or effluent from the patient. The PD fluid containers or bags may be partitioned by an interior polymer layer into separate fresh and used fluid compartments. Here, a supply line is placed in fluid communication with the fresh PD fluid compartment, while a drain line is placed in fluid communication with the used PD fluid compartment. Fresh dialysis fluid is delivered from the fresh PD fluid compartment, through the supply line, through the patient line, to the patient. Used dialysis fluid is delivered from the patient, through the patient line, through the drain line, to the drain compartment. In a variation of this embodiment, ports from the fresh PD fluid compartment and the used PD fluid compartment are each fitted with a one-way valve and are tee′d together to form a single inlet/outlet port that connects to a single supply/drain line extending outside of the chamber to the pump line or tube. The first or fresh one-way valve is oriented to only open under negative pressure to enable fresh PD fluid to be pulled from the fresh PD fluid compartment. The second or used one-way valve is oriented to only open under positive pressure to enable used PD fluid to be delivered into the used PD fluid compartment.
The PD fluid containers or bags may alternatively be configured so that the mixing of fresh and used PD fluid, which are allowed to contact each other at an interface, is reduced to a negligible amount. Here, a supply line is placed in fluid communication with a fresh PD fluid end of the container, while a drain line is placed in fluid communication with a used PD fluid end of the container. Fresh dialysis fluid is delivered from the fresh PD fluid end, through the supply line, through the patient line, to the patient. Used dialysis fluid is delivered from the patient, through the patient line, through the drain line, to the drain side of the container. A drain inlet barrier may be positioned in the drain side of the container to deflect and make laminar the flow of incoming drain fluid.
A control unit having one or more processor and memory is provided to (i) control all of the fluid valves, a bidirectional pump, the heater and (ii) receive signals from the weigh scale and other sensors, such as temperature and pressure sensors, to perform each of the pumping sequences described herein. The control unit also interfaces with a user interface. The user interface may be provided with a touchscreen and/or electromechanical pushbuttons to allow the user or patient to enter parameters for treatment and a display screen for providing information, such as treatment status information. The control unit may also communicate over a network with a doctor or clinician computer or computer system to upload treatment and compliance data and to receive device and treatment prescriptions from the doctor or clinician.
In light of the disclosure set forth herein, and without limiting the disclosure in any way, in a first aspect, which may be used with any other aspect described herein, or portion thereof, a peritoneal dialysis (“PD”) system comprises a cycler including a weigh scale, a chamber positioned to be weighed by the weigh scale, a heater positioned to heat an inside of the chamber, a plurality of valves supported by the chamber or a housing of the cycler, a pump supported by the chamber or a housing of the cycler, and a control unit operable with the weigh scale, the heater, the plurality of valves and the pump; and a disposable set including a PD fluid container sized to fit within the chamber so as to be weighed by the weigh scale and heated by the heater, a supply line in fluid communication with the PD fluid container and extending outside of the chamber, a drain container sized to fit within the chamber so as to be weighed by the weigh scale, a drain line in fluid communication with the drain container and extending outside of the chamber, and a patient line positioned on an opposing side of the pump from the supply line and the drain line, wherein the control unit is configured to operate the plurality of valves and the pump bidirectionally to pump (i) used dialysis fluid from the patient line, through the drain line, to the drain container and (ii) fresh dialysis fluid from the PD fluid container, through the supply line, and through the patient line.
In a second aspect, which may be used with any other aspect described herein, or portion thereof, the plurality of valves include a supply line valve, a drain line valve and a patient line valve, wherein the control unit is configured to open the drain line valve and the patient line valve for (i) of claim 1, and wherein the control unit is configured to open the supply line valve and the patient line valve for (ii) of claim 1.
In a third aspect, which may be used with any other aspect described herein, or portion thereof, at least one of the supply line valve, drain line valve or patient line valve is a pinch valve that opens or occludes the supply line, drain line or patient line, respectively.
In a fourth aspect, which may be used with any other aspect described herein, or portion thereof, the pump is a peristaltic pump, and wherein the disposable set includes a peristaltic pumping tube located between (a) the supply line and the patient line and (b) the drain line and the patient line.
in a fifth aspect, which may be used with any other aspect described herein, or portion thereof, the PD fluid container is a first PD fluid container and the supply line is a first supply line, and which includes a second PD fluid container sized to fit within the chamber so as to be weighed by the weigh scale and heated by the heater, and a second supply line in fluid communication with the second PD fluid container and extending outside of the chamber.
In a sixth aspect, which may be used with any other aspect described herein, or portion thereof, the chamber is configured for the second PD fluid container to be placed on top of the first PD fluid container.
In a seventh aspect, which may be used with any other aspect described herein, or portion thereof, the chamber is configured for the second PD fluid container to be placed adjacent to the first PD fluid container.
In an eighth aspect, which may be used with any other aspect described herein, or portion thereof, the patient line is positioned on the opposing side of the pump from the supply line, the drain line and the second supply line.
In a ninth aspect, which may be used with any other aspect described herein, or portion thereof, the supply line mates with a container line extending from the PD fluid container.
In a tenth aspect, which may be used with any other aspect described herein, or portion thereof, the mating of the supply line and the container line occurs along a side of the chamber supporting at least one of the supply line or the container line.
In an eleventh aspect, which may be used with any other aspect described herein, or portion thereof, the chamber is configured for the supply line to extend into the chamber for connection to the PD fluid container.
In a twelfth aspect, which may be used with any other aspect described herein, or portion thereof, the disposable set further includes a terminal drain line, and wherein the control unit is further configured to operate at least some of the plurality of valves and the pump to pump used dialysis fluid from the drain container, after the used dialysis fluid is weighed by the weigh scale, to the terminal drain line.
In a thirteenth aspect, which may be used with any other aspect described herein, or portion thereof, the terminal drain line is positioned along with the patient line on the opposing side of the pump from the supply line and the drain line.
In a fourteenth aspect, which may be used with any other aspect described herein, or portion thereof, the terminal drain line extends to a terminal drain container or to a house drain.
In a fifteenth aspect, which may be used with any other aspect described herein, or portion thereof, a peritoneal dialysis (“PD”) system comprises a cycler including a weigh scale, a chamber positioned to be weighed by the weigh scale, a heater positioned to heat an inside of the chamber, a plurality of valves supported by the chamber or a housing of the cycler, a pump supported by the chamber or a housing of the cycler, and a control unit operable with the weigh scale, the heater, the plurality of valves and the pump; and a disposable set including a PD fluid container sized to fit within the chamber so as to be weighed by the weigh scale and heated by the heater, the PD fluid container including a fresh PD fluid compartment and a used PD fluid compartment, a supply line in fluid communication with the fresh PD fluid compartment and extending outside of the chamber, a drain line in fluid communication with the used PD fluid compartment and extending outside of the chamber, and a patient line positioned on an opposing side of the pump from the supply line and the drain line, wherein the control unit is configured to operate the plurality of valves and the pump bidirectionally to pump (i) used dialysis fluid from the patient line, through the drain line, to the used PD fluid compartment and (ii) fresh dialysis fluid from the fresh PD fluid compartment, through the supply line, and through the patient line.
In a sixteenth aspect, which may be used with any other aspect described herein, or portion thereof. (i) the supply line mates with a fresh compartment line extending from the fresh PD fluid compartment and (ii) the drain line mates with a used compartment line extending from the used PD fluid compartment.
In a seventeenth aspect, which may be used with any other aspect described herein, or portion thereof, the chamber is configured for (i) the supply line to extend into the chamber for connection to the fresh PD fluid compartment and (ii) the drain line to extend into the chamber for connection to the used PD fluid compartment.
In an eighteenth aspect, which may be used with any other aspect described herein, or portion thereof, the chamber is sized to hold an entire fresh PD fluid volume at a beginning of a treatment and used PD fluid from multiple drains at the end of the treatment.
In a nineteenth aspect, which may be used with any other aspect described herein, or portion thereof, a peritoneal dialysis (“PD”) system comprises a cycler including a weigh scale, a chamber positioned to be weighed by the weigh scale, a heater positioned to heat an inside of the chamber, a plurality of valves supported by the chamber or a housing of the cycler, a pump supported by the chamber or a housing of the cycler, and a control unit operable with the weigh scale, the heater, the plurality of valves and the pump; and a disposable set including a PD fluid container sized to fit within the chamber so as to be weighed by the weigh scale and heated by the heater, the PD fluid container including a fresh PD fluid compartment and a used PD fluid compartment, a first one-way valve in fluid communication with the fresh PD fluid compartment, the first one-way valve oriented to open under negative pressure from outside the fresh PD fluid compartment, a second one-way valve in fluid communication with the used PD fluid compartment, the second one-way valve oriented to open under positive pressure from outside the used PD fluid compartment, a supply/drain line in fluid communication with the first and second one-way valves, the supply/drain line extending outside of the chamber, and a patient line positioned on an opposing side of the pump from the supply/drain line, wherein the control unit is configured to operate the plurality of valves and the pump bidirectionally to pump (i) used dialysis fluid from the patient line, through the supply/drain line and the second one-way valve, to the used PD fluid compartment and (ii) fresh dialysis fluid from the fresh PD fluid compartment, through the first one-way valve and the supply/drain line, through the patient line.
In a twentieth aspect, which may be used with any other aspect described herein, or portion thereof, wherein the supply/drain line mates with a tee extending to a first port holding the first one-way valve and a second port holding the second one-way valve.
In a twenty-first aspect, which may be used with any other aspect described herein, or portion thereof, the chamber is sized to hold an entire fresh PD fluid volume at a beginning of a treatment and used PD fluid from multiple drains at the end of the treatment.
In a twenty-second aspect, which may be used with any other aspect described herein, or portion thereof, a peritoneal dialysis (“PD”) system comprises a cycler including a weigh scale, a chamber positioned to be weighed by the weigh scale, a heater positioned to heat an inside of the chamber, a plurality of valves supported by the chamber or a housing of the cycler, a pump supported by the chamber or a housing of the cycler, and a control unit operable with the weigh scale, the heater, the plurality of valves and the pump; and a disposable set including a PD fluid container sized to fit within the chamber so as to be weighed by the weigh scale and heated by the heater, the PD fluid container including a fresh PD fluid end and a used PD fluid end, a supply line in fluid communication with the fresh PD fluid end and extending outside of the chamber, a drain line in fluid communication with the used PD fluid end and extending outside of the chamber, and a patient line positioned on an opposing side of the pump from the supply line and the drain line, wherein the control unit is configured to operate the plurality of valves and the pump bidirectionally to pump (i) used dialysis fluid from the patient line, through the drain line, to the used PD fluid end of the PD fluid container and (ii) fresh dialysis fluid from the fresh PD fluid end of the PD fluid container, through the supply line, and through the patient line.
In a twenty-third aspect, which may be used with any other aspect described herein, or portion thereof. (i) the supply line mates with a fresh compartment line extending from the fresh PD fluid end of the PD fluid container and (ii) the drain line mates with a used compartment line extending from the used PD fluid end of the PD fluid container.
In a twenty-fourth aspect, which may be used with any other aspect described herein, or portion thereof, the chamber is configured for the (i) supply line to extend into the chamber for connection to the fresh PD fluid end of the PD fluid container and (ii) the drain line to extends into the chamber for connection to the used PD fluid end of the PD fluid container.
In a twenty-fifth aspect, which may be used with any other aspect described herein, or portion thereof, the used PD fluid end of the PD fluid container includes a drain inlet barrier for dampening incoming used PD fluid flow.
In a twenty-sixth aspect, which may be used with any other aspect described herein, or portion thereof, fresh PD fluid and used PD fluid within the PD fluid container meet at a fresh/used PD fluid interface.
In a twenty-seventh aspect, any of the features, functionality and alternatives described in connection with any one or more of
It is accordingly an advantage of the present disclosure to provide an automated peritoneal dialysis (“APD”) cycler that is massed balanced to provide needed accuracy to control fill and drain volumes and the difference between fill and drain volumes.
It is another advantage of the present disclosure to provide an APD cycler that uses a relatively simple disposable set.
It is a further advantage of the present disclosure to provide a relatively quiet APD cycler.
It is still another advantage of the present disclosure to provide an APD cycler that is relatively cost effective.
It is yet a further advantage of the present disclosure to provide an APD system that is relatively easy to setup and use.
It is yet another advantage of the present disclosure to provide an APD system that employs a relatively low cost disposable set.
It is still another advantage of the present disclosure to hold fresh PD fluid supply containers inside of a chamber so that they are contained within the overall system.
Additional features and advantages are described in, and will be apparent from, the following Detailed Description and the Figures. The features and advantages described herein are not all-inclusive and, in particular, many additional features and advantages will be apparent to one of ordinary skill in the art in view of the figures and description. Also, any particular embodiment does not have to have all of the advantages listed herein and it is expressly contemplated to claim individual advantageous embodiments separately. Moreover, it should be noted that the language used in the specification has been selected principally for readability and instructional purposes, and not to limit the scope of the inventive subject matter.
Referring now to the drawings and in particular to
Disposable set 100, including all tubing, connectors and containers or bags, is made of a medically safe material such as PVC or a non-PVC material, such as one of the polymers listed above.
The initially wet portion of disposable set 100 shown in
As illustrated in
Cycler 20 may include a heater 32, such as an electrical plate heater, which is located inside of chamber 22, e.g., supported by the bottom 24 of the chamber. One or more temperature sensor 34a to 34c is positioned to measure any one or more of (i) the temperature of heater 32 (34a), (ii) the surface temperature of any one or more or all of the dialysis fluid containers or bags located within chamber 22 (34b), and/or (iii) the air temperature within chamber 22 (34c). The output of any one or more temperature sensor 34a to 34c may be used as feedback to a control unit 50 controlling heater 32 and/or for a display on a user interface 58 of system 10.
Referring now to
A peristaltic pump actuator 76 is operable in clockwise and counterclockwise directions to pump fresh and used dialysis fluid through peristaltic pumping tube 116. Peristaltic pump actuator 76 may for example include an electrically actuated stepper motor that moves a peristaltic pump rotor, which pinches peristaltic pumping tube 116 against a raceway to drive fluid in a desired direction. Pressure sensing pod 118 operates with pressure transducer 78. Each of control unit 50, user interface 58, valves 62, 64, 66, 68, 70 and 74, peristaltic pump actuator 76 and pressure transducer 78 may be located, for example, on the outer surface of one or more of sides 26a to 26c of chamber 22, the surface on the page (cutaway to see inside the chamber), and/or lid 28. In the illustrated example, control unit 50 and user interface 58 may be located on the outer surface of side 26a, while valves 62, 64, 66, 68, 70 and 74, peristaltic pump actuator 76 and pressure transducer 78 are located on the outer surface of side 26b. Alternatively, each of the structures is located on the same side of chamber 22. In an embodiment, peristaltic pump actuator 76 is located so that patient line 120 is prevented from tugging or pulling on chamber 22, which may affect the reading of scale 40. For example, a service loop or other type of strain relief structure may be provided in the tubing on one or both sides of peristaltic pump actuator 76.
Each of temperature sensors 34a to 34c, heater 32, valves 62, 64, 66, 68, 70 and 74, peristaltic pump actuator 76 and pressure transducer 78 is under the control of and/or outputs to control unit 50. Although it may not be explicitly stated below, control unit 50 may control any of the valve states and peristaltic pump actuations described herein. Control unit 50 receives output signals from any one or more temperature sensor 34a to 34c to use as feedback to control heater 32 so as to heat fresh dialysis fluid within container or bags 132a to 132c to body temperature or 37° C. Control unit 50 receives output signals from pressure transducer 78 to use as feedback to control the speed of peristaltic pump actuator 76 so as to maintain any patient pumping within a safe pressure limit, e.g., within one to five psig for patient fills (e.g., two psig (14 kPa)) and −1.0 to −3.0 psig (e.g., 1.3 psig (−9 kPa)) for patient drains. Draining from drain container or bag 114 through terminal drain line 124 to a final drain container or house drain may be performed at higher pressures and flowrates because it does not involve the patient. Control unit 50 may employ proportional, integral and derivative (“PID”) control for either one or both of PD fluid temperature and pumping pressure.
It is quite possible that the patient is not full of used dialysis fluid or effluent at the beginning of treatment. In such a case, treatment begins with a patient fill. It is also possible that the patient does not receive a last fill at the end of treatment (e.g., if the last fill PD fluid container or bag 132c is not provided or if the patient has drained some time during the day). It should be appreciated however that control unit 50 may be configured to default to attempting a patient drain (safety drain) at the beginning of each treatment in case the patient may have forgotten to perform a drain at the end of a previous treatment or from an exchange in between treatments.
In any case, it is contemplated to prime disposable set 100 prior to the first patient fill. For priming, control unit 50 causes each supply valve 64, 66 and 68 and final drain valve 74 to be opened and peristaltic pump actuator 76 to operate in a counterclockwise direction to pull fresh PD fluid from each of PD fluid containers 132a to 132c, which in turn drives air in lines 134/104, 136/106, 138/108 and 102 into terminal drain line 124, to a terminal drain container or house drain. Control unit 50 in an embodiment sequences supply valves 64, 66 and 68 and drain valve 74 open so that control unit 50 can confirm via signals from weigh scale 40 that fluid has traveled to each of the valves. The amount of fresh PD fluid needed and delivered here may be known via corresponding tubing volume and controlled via a corresponding weight sensed by weigh scale 40, e.g., plus an engineering factor of additional PD fluid. It should be appreciated that an initial drain could be used to prime patient line 120, manifold line 102 and drain line 112, pushing air into drain container or bag 114, after which the above priming sequence pushes much of the effluent priming fluid to terminal drain. It may however be prudent not to rely on an initial patient drain for priming, e.g., in case the patient has less effluent to drain than expected. Here, or if an initial drain is not provided, patient line 120 may be primed with fresh PD fluid up to a hydrophobic membrane provided with patient connector 122, or up to a prime sensor (e.g., optical, capacitive or other) outputting to control unit 50 and against which patient connector 122 at the end of patient line 120 is located prior to treatment.
Referring now to
In the illustrated embodiment, fresh PD fluid port 240a is fitted with a check valve or one-way valve 260a (e.g., duck-billed check valve) that is oriented to open only under negative PD fluid pressure and to remain closed under positive PD fluid pressure. Here, one-way valve 260a is pressure closed shut when used PD fluid is delivered to container 252a, 252b but opens under negative pressure to enable fresh PD fluid to be pulled from fresh PD fluid compartment 234 during a patient fill. Used PD fluid port 240b is in turn fitted with a check valve or one-way valve 260b (e.g., duck-billed check valve) that is oriented to open only under positive PD fluid pressure and to remain closed under negative PD fluid pressure. Here, one-way valve 260b remains closed when fresh PD fluid is pulled from container 252a, 252b but opens under positive pressure to enable used PD fluid to be pushed into used PD fluid compartment 236 during a patient drain.
PD fluid container or bag 242a, 242b may be provided in a size allowing for a three liter initial patient drain, e.g., as an overall nine liter container assuming the container holds six liters of fresh PD fluid. PD fluid container or bag 242a, 242b may be packaged with the additional material rolled-up or otherwise pressed closed to mitigate the amount of air that needs to be displaced when an initial drain volume is introduced. It may be that only an initial one of PD fluid containers or bags 242a, 242b needs to be provided with an additional empty volume for an initial drain. That is, when the first operation using the second one of PD fluid containers or bags 242a, 242b is a patient fill, space is created for a subsequent drain, so an initial free space is not needed. If the patient's therapy does not call for an initial drain then none of PD fluid containers or bags 242a, 242b needs to be provided with an additional empty volume for an initial drain.
Alternative disposable set 200 also includes drain line segments 204 and 206 extending from manifold line 102 adjacent to supply lines 104 and 106, respectively. Drain line segments 204 and 206 each terminate at a drain line connector 110c. Supply line connector 110a and drain line connector 110c are illustrated as being provided together, e.g., within one housing having separate connection heads, but can alternatively be provided as separate connectors located adjacent to each other. Supply lines 104, 106 and 108 are used for patient fills of a treatment, while drain line segments 204 and 206 are used for patient drains.
For use with container 252a, 252b of
It is quite possible that the patient is not full of used dialysis fluid or effluent at the beginning of treatment, which may occur if the patient does not receive a last fill at the end of treatment (e.g., last fill container 132c is not provided). In such a case, treatment begins with a patient fill. Again, control unit 50 may be configured to default to attempting a patient drain (safety drain) at the beginning of each treatment, which attempts to pull a small amount off effluent from the patient by applying a small negative pressure that does not cause the patient discomfort. When trying to pull the small amount of effluent, control unit 50 may (i) if a negative pressure increase is sensed, prompt the patient to check and see if a clamp that should be open is closed or if a patient or supply line is kinked, (ii) if all lines are clear after detecting the negative pressure increase, determine that the patient is dry and begin treatment with a patient fill, and (iii) if the negative pressure increase is not sensed, determine that the patient is full of effluent and begin treatment with a patient drain.
In any case, it is contemplated to prime disposable set 200 prior to the first patient fill. Here, control unit 50 causes each supply valve 64, 66 and 68 and patient line valve 70 to be opened and peristaltic pump actuator 76 to operate in a counterclockwise direction to pull fresh PD fluid from each of PD fluid containers 232a or 242a, 232b or 242b and 132c, which in turn drives air in lines 134/104, 136/106, 138/108 and 102 into patient line 120. In one priming example, control unit 50 causes supply valve 68 and patient valve 70 to open and peristaltic pump actuator 76 to slowly pull fluid from container 132c, so that fresh dialysis fluid reaches the inlet of the pump. Control unit 50 then causes supply valve 68 to close and first drain segment valve 84 to open and reverses peristaltic pump actuator 76 to push fresh dialysis fluid into used compartment line 254. Control unit 50 then causes supply valve 66 and patient valve 70 to open and peristaltic pump actuator 76 to slowly pull fluid from container 232b, 242b, so that fresh dialysis fluid again reaches the inlet of the pump. Control unit 50 then causes supply valve 66 to close and second drain segment valve 86 to open and reverses peristaltic pump actuator 76 to push fresh dialysis fluid into used compartment line 256. Control unit 50 then, assuming container 232b, 242b is used for the first fill, opens supply valve 64 and patient valve 70 to prime the whole set up to patient connector 122.
The amount of fresh PD fluid needed and delivered during priming may be known via corresponding tubing volume and controlled via a corresponding weight sensed by weigh scale 40. Priming patient line 120 up to patient connector 122 may be performed by pushing fresh PD fluid up to a hydrophobic membrane provided with patient connector 122, or to a prime sensor (e.g., optical, capacitive or other) outputting to control unit 50 and against which patient connector 122 at the distal end of patient line 120 is located prior to treatment.
The patient after treatment may wheel all of the used dialysis fluid to a house drain for removal, which is advantageous because less disposable material is used, saving cost and lessening environmental impact, and because a leaking house drain line is prevented. Each of the pumping procedures performed in connection with disposable set 200, except the priming procedure, involves either removing used dialysis fluid from or delivering fresh dialysis fluid to the patient. Control unit 50 receives output signals from pressure transducer 78 operating with pressure sensing pod 118 for each of the patient pumping procedures to use as feedback to control the speed of peristaltic pump actuator 76 so as to maintain any patient pumping within a safe pressure limit, e.g., within one to five psig for patient fills (e.g., two psig (14 kPa)) and −1.0 to −3.0 psig (e.g., 1.3 psig (−9 kPa)) for patient drains. Control unit 50 may alternatively be programmed to remove used dialysis fluid during treatment dwells or after treatment to drain using a dedicated drain line so that the patient does not have to transport containers full of effluent.
The sequence described above for
It should be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present subject matter and without diminishing its intended advantages. It is therefore intended that such changes and modifications be covered by the appended claims. For example, pneumatic valves, or other types of valves, may be used instead of electrically actuated pinch valves. Other types of pumping may also be used, such as diaphragm pumping and/or pneumatic pumping. In another example, inline heating may be used alternatively. In a further example, while the present disclosure illustrates the supply lines being matted via connectors 110a and 110b at a side, surface or wall of chamber 22, it is also contemplated to allow the supply lines of disposable set 100 to instead extend through a hole or slot in the side, surface or wall of chamber 22 and be connected directly to dialysis fluid containers or bags 132a, 132b, 132c, 232a, 232b, 242a and 242b. The same holds true for the drain lines associated with dialysis fluid containers or bags 232a, 232b, 242a and 242b. In a further example, while the pump and valve actuators are illustrated and described as being located outside of chamber 22, one or more or all of the pump and valve actuators may instead be located inside of the chamber. Also, while the pump and valve actuators are illustrated and described as being attached directly to chamber 22, one or more or all of the pump and valve actuators may instead be attached to a housing of the cycler supporting, providing or forming the chamber.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2022/017749 | 2/24/2022 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 63153085 | Feb 2021 | US |
