Wearable kidney

• US 20070213665A1
• Filed: 03/08/2006
• Published: 09/13/2007
• Est. Priority Date: 03/08/2006
• Status: Active Grant

• Current Assignee: Fresenius Medical Care Holdings Incorporated (Fresenius Medical Care AG)
• Original Assignee: Fresenius Medical Care Holdings Incorporated (Fresenius Medical Care AG)
• Inventors: Curtin, Conor, Ofsthun, Norma, Lipps, Benjamin, Sandford, Harold
• Granted Patent: US 8,715,221 B2
• Time in Patent Office: Days
• US Class Current: 604/131
• CPC Class Codes: A61M 1/1696 with dialysate regeneration
• CPC Class Codes: A61M 1/28 Peritoneal dialysis ; Other peritoneal treatment, e.g. oxygenation
• CPC Class Codes: A61M 1/284 Continuous flow peritoneal dialysis [CFPD]
• CPC Class Codes: A61M 2209/088 on the body

Abstract

The present invention relates to a wearable peritoneal dialysis system and a replaceable cartridge in the wearable peritoneal dialysis system that regenerates the peritoneal dialysis solution without removing essential ions from the solution and, consequently, the patient. The invention also relates to methods of removing uremic waste metabolites from a patient using the wearable peritoneal dialysis system. A source of one or more enzymes that degrades uremic waste metabolites can be administered orally in conjunction with use of the wearable peritoneal dialysis system such that the load of toxins needing to be eliminated by the wearable peritoneal dialysis system is reduced. The wearable peritoneal dialysis system is meant to operate continuously or semi-continuously, its components small and light enough that it can be comfortably worn by a patient constantly, without burden.

Claims

1. A wearable peritoneal dialysis system for a patient comprising:

an access port coupled to a component for providing inflow to and outflow from the patient'"'"'s peritoneal cavity;

a volume of peritoneal dialysis solution that is infused into and moved out of the patient'"'"'s peritoneal cavity, thereby removing from the patient uremic waste metabolites that have diffused into the peritoneal dialysis solution;

a closed fluid system loop for circulating the peritoneal dialysis solution from the patient, throughout the system and back into the patient;

at least one pump attached to the fluid system loop for infusing the peritoneal dialysis solution into the patient'"'"'s peritoneal cavity and moving the peritoneal dialysis solution containing uremic waste metabolites out of the patient'"'"'s peritoneal cavity and into the fluid system loop;

a replaceable drain container attached to the fluid system loop for draining excess fluid;

a filter attached to the fluid system loop for removing particulates and debris from the peritoneal dialysis solution containing uremic waste metabolites and;

a replaceable cartridge attached to the fluid system loop for regenerating the peritoneal dialysis solution, said replaceable cartridge having an urea removal layer that rejects calcium and magnesium ions.

2. The wearable peritoneal dialysis system of claim 1 wherein the system is used in conjunction with a source of one or more enzymes that degrade uremic waste metabolites, the source of one or more enzymes orally administered to the patient, thereby reducing the load of uremic waste metabolites to be removed from the patient by the system.

3. The wearable peritoneal dialysis system of claim 2 wherein the source of the one or more enzymes is a cell selected from the group consisting of a microbial cell, a yeast cell and a mammalian cell.

4. The wearable peritoneal dialysis system of claim 3 wherein the one or more enzymes are selected from the group consisting of urease, creatininase and uric acid.

5. The wearable peritoneal dialysis system of claim 2 wherein the replaceable cartridge comprises:

a purification layer for removing heavy metals, oxidants and other uremic waste metabolites from said peritoneal dialysis solution;

a urea removal layer that rejects calcium and magnesium ions; and

an ion-exchange layer for removing phosphate and sulfate from said peritoneal dialysis solution.

6. The wearable peritoneal dialysis system of claim 5 wherein the urea removal layer comprises urea removal components selected from the group consisting of:

a strong acid cation resin together with a weak base resin, a dual-property resin and a urea-degradation enzyme together with an ion exchange sorbent.

7. The wearable peritoneal dialysis system of claim 6 wherein the urea removal layer further comprises a composition that rejects calcium and magnesium ions selected from the group consisting of:

hollow fibers comprised of an ion-selective nanofiltration membrane, hollow fibers coated with a material that rejects calcium and magnesium ions and an encapsulation surrounding the urea removal components, the encapsulation comprised of a material that rejects calcium and magnesium ions.

8. The wearable peritoneal dialysis system of claim 7 wherein each layer of the cartridge is removable and replaceable.

9. The wearable peritoneal dialysis system of claim 8 further comprising a mix container attached to the fluid system loop to re-mix the regenerated peritoneal dialysis solution with glucose.

10. The wearable peritoneal dialysis system of claim 9 further comprising a three-way valve to connect the flow of the re-mixed and regenerated peritoneal dialysis solution to an initial priming point of the fluid system loop.

11. The wearable peritoneal dialysis system of claim 10 further comprising a filter attached to the fluid system loop to remove bacterial contamination from the regenerated peritoneal dialysis solution.

12. The wearable peritoneal dialysis system of claim 11 further comprising a microprocessor in communication with the components of the fluid system loop, said microprocessor controlling the pump flow rates and the timing and sequencing of the components of the dialysis system.

13. A replaceable cartridge for regenerating peritoneal dialysis solution comprising:

a purification layer for removing heavy metals, oxidants and other uremic waste metabolites from said peritoneal dialysis solution;

a urea removal layer that rejects calcium and magnesium ions; and

an ion-exchange layer for removing phosphate and sulfate from said peritoneal dialysis solution.

14. The replaceable cartridge of claim 13 wherein the purification layer comprises activated carbon.

15. The replaceable cartridge of claim 13 wherein the ion-exchange layer is comprised of one selected from the group consisting of a polymeric phosphate binder and an ion-exchange resin.

16. The replaceable cartridge of claim 13 wherein the urea removal layer comprises a composition that rejects calcium and magnesium ions selected from the group consisting of:

hollow fibers comprised of an ion-selective nanofiltration membrane, hollow fibers coated with a material that rejects calcium and magnesium ions and an encapsulation surrounding the urea removal components, the encapsulation comprised of a material that rejects calcium and magnesium ions.

17. The replaceable cartridge of claim 16 wherein the material coating the hollow fibers and the encapsulation surrounding the urea removal components is positively charged.

18. The replaceable cartridge of claim 17 wherein the material coating the hollow fibers and the encapsulation surrounding the urea removal components is selected from the group consisting of cellulose acetate, fatty acids and polymer chains.

19. The replaceable cartridge of claim 16 wherein the urea removal layer further comprises:

a strong acid cation resin to absorb the urea; and

a weak base anion resin to absorb the counter ions released by the absorption of urea by said strong acid cation resin.

20. The replaceable cartridge of claim 19 wherein a dual-property resin is both the strong acid resin and the weak base resin.

21. The replaceable cartridge of claim 16 wherein the urea removal layer further comprises:

an enzyme to degrade the urea; and

an ion-exchange sorbent to absorb the urea degradation products.

22. The replaceable cartridge of claim 21 wherein the enzyme to degrade the urea is urease.

23. The replaceable cartridge of claim 21 wherein the ion exchange sorbent is a zirconium phosphate resin.

24. The replaceable cartridge of claim 16 wherein each layer of the cartridge is removable and replaceable.

25. A method for the removal of uremic waste metabolites from a patient using a wearable peritoneal dialysis system comprising:

providing a volume of peritoneal dialysis solution;

pumping the peritoneal dialysis solution into the peritoneal cavity of the patient through an access port, allowing the patient'"'"'s uremic waste metabolites to diffuse across the peritoneal membrane into the peritoneal dialysis solution;

pumping the peritoneal dialysis solution containing uremic waste metabolites out of the patient and into the system;

draining excess fluid into a replaceable drain container;

filtering particulates and debris from the peritoneal dialysis solution containing uremic waste metabolites;

regenerating the peritoneal dialysis solution containing uremic waste metabolites using a replaceable cartridge having an urea removal layer that rejects calcium and magnesium ions; and

returning the regenerated peritoneal dialysis solution to the patient'"'"'s peritoneal cavity.

26. The method of claim 25 further comprising orally administering to a patient a source of one or more enzymes that degrade uremic waste metabolites, thereby reducing the load of uremic waste metabolites to be removed from the patient by the peritoneal dialysis system.

27. The method of claim 26 further comprising controlling the pump flow rates and the timing and sequencing of the components of the dialysis system using a microprocessor.