POTASSIUM LOADED ION-EXCHANGE MATERIAL FOR USE IN A DIALYSATE REGENERATION SYSTEM

• US 20140158538A1
• Filed: 02/02/2013
• Published: 06/12/2014
• Est. Priority Date: 12/10/2012
• Status: Active Grant

• Current Assignee: Mozarc Medical US LLC
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Gerber, Martin T., Lura, David B., Meyer, Thomas E., Pudil, Bryant J., COLLIER, Kenneth J.
• Granted Patent: US 9,399,090 B2
• Time in Patent Office: Days
• US Class Current: 204/519
• CPC Class Codes: A61M 1/1654 Dialysates therefor
• CPC Class Codes: A61M 1/1656 Apparatus for preparing dialysates
• CPC Class Codes: A61M 1/1666 by dissolving solids
• CPC Class Codes: A61M 1/1668 Details of containers
• CPC Class Codes: A61M 1/1672 using membrane filters, e.g. for sterilising the dialysate
• CPC Class Codes: A61M 1/1696 with dialysate regeneration
• CPC Class Codes: A61M 1/287 Dialysates therefor
• CPC Class Codes: A61M 2205/3317 Electromagnetic, inductive or dielectric measuring means

Abstract

Systems and methods for managing the potassium concentration of a dialysate fluid during hemodialysis therapy using cation exchange materials that do not release sodium ions.

Claims

1. A system for kidney replacement therapy, comprising:

a dialysate flow loop for circulating a dialysate through a dialyzer where at least one waste species enters the dialysate;

a dialysate regeneration unit for decreasing the concentration or conductivity of at least one waste species and releasing potassium ions to the dialysate; and

a potassium management system for modifying the potassium ion concentration of the dialysate in the dialysate flow loop, the potassium-modified fluid having a potassium ion concentration or conductivity that is higher or lower than the fluid in the dialysate flow loop.

2. The system of claim 1, further comprising a deionization resin to lower the sodium ion concentration of the dialysate entering the potassium management system.

3. The system of claim 2, wherein the deionization resin substantially removes sodium ions from the dialysate entering the potassium management system.

4. The system of claim 1, wherein the potassium management system further comprises a deionization resin to lower the potassium ion concentration from the dialysate.

5. The system of claim 1, further comprising a control pump connected to an ultrafiltrate reservoir that removes or adds fluid to the dialysate flow loop downstream from the dialyzer, wherein operation of the control pump in an efflux direction causes net removal of fluid from the blood on an extracorporeal side of a membrane in the dialyzer and operation of the control pump in an influx direction causes net addition of fluid to the blood on the extracorporeal side of the membrane.

6. The system of claim 1, further comprising a potassium ion or conductivity detector that measures the conductivity or potassium ion concentration of the dialysate.

7. The system of claim 1, wherein the potassium management system is an electrodialysis cell comprising at least a concentrate flow channel, a diluate flow channel and an electrode rinse flow channel, wherein potassium ions move from the diluate flow channel to the concentrate flow channel in response to an electric field, wherein the potassium-modified fluid is generated in the diluate flow channel for addition to the dialysate flow loop.

8. The system of claim 7, wherein the diluate flow channel is defined by a cation and an anion exchange membrane, the concentrate flow channel is defined by a cation and anion exchange membrane, and an electrode rinse channel is defined by a cation exchange membrane wherein the diluate flow channel is separated from the one or more concentrate flow channel by either a cation or anion exchange membrane.

9. The system of claim 7, wherein the flow channels are defined in part by a bipolar membrane.

10. The system of claim 7, further comprising an electrode rinse pump and electrode rinse reservoir for circulating the electrode rinse solution through the electrode rinse flow channel.

11. The system of claim 7, further comprising a concentrate solution and a concentrate pump for circulating the concentrate solution through the concentrate flow channel and an electrode rinse pump and electrode rinse reservoir for circulating the electrode rinse solution through the electrode rinse flow channel.

12. The system of claim 6, wherein ultrafiltrate directed toward the ultrafiltrate reservoir passes through the potassium management system prior to collection in the ultrafiltrate reservoir.

13. The system of claim 1, wherein the dialysate flow loop further comprises a dialysate reservoir located downstream from the dialyzer and upstream from the dialysate regeneration unit.

14. The system of claim 12, wherein the potassium management system is an electrodialysis cell comprising at least a concentrate flow channel, a diluate flow channel and an electrode rinse flow channel and ultrafiltrate passes through the concentrate flow channel prior to collection in the ultrafiltrate reservoir.

15. The system of claim 1, wherein the potassium-modified fluid has a potassium ion conductivity or concentration less than the dialysate in the dialysate flow loop and thereby capable of reducing the concentration of potassium in the dialysate flow loop upon addition to the dialysate.

16. The system of claim 1, wherein the potassium management system modifies the conductivity or potassium ion concentration by application of an electrical field.

17. The system of claim 1, wherein the potassium management system generates the potassium-modified fluid from dialysate removed from the dialysate flow loop.

18. The system of claim 17, wherein dialysate from the dialysate flow loop is directed through the potassium management system or bypasses the potassium management system using a by-pass regulator.

19. The system of claim 1, wherein potassium-modified fluid from the potassium management system is added to the dialysate flow loop at a position between an inlet of the dialyzer and an outlet of the dialysate regeneration unit.

20. The system of claim 1, wherein the potassium management system comprises a capacitive deionization cell.

21. The system of claim 20, wherein the capacitive deionization cell can store potassium ions for generating a potassium-modified fluid having a higher concentration than the fluid entering the capacitive deionization cell.

22. The system of claim 20, wherein the potassium management system comprises at least two capacitive deionization cells, wherein one capacitive deionization cell can be regenerated by passing a flushing fluid through the capacitive deionization cell while the other capacitive deionization remains operable to generate the potassium-modified fluid.

33. The system of claim 1, wherein the system is controlled compliant.

34. The system of claim 1, wherein the system selectively meters fluid into and out of the dialysate flow loop.

35. The system of claim 1, wherein the system selectively meters fluid into and out of the dialysate flow loop using any one of a control pump, a water pump, a salination pump, an acid concentrate pump, a replacement fluid pump, and combinations thereof.

36. The system of claim 1, wherein the system provides for bi-directional flow.

23. A method for regenerating a dialysate, comprising:

circulating a dialysate in a dialysate flow loop wherein the dialysate contacts a dialyzer and a dialysate regeneration unit and a waste species enters the dialysate at the dialyzer and is at least partially removed by the dialysate regeneration unit; and

modifying the potassium concentration of a provided input fluid using a potassium management system to modify the potassium concentration of the dialysate within the dialysate flow loop.

24. The method of claim 23, wherein the potassium concentration of the provided input fluid is modified by application of an electrical field to generate the potassium-modified fluid.

25. The method of claim 23, wherein the dialysate is contacted with a deionization resin to substantially remove sodium ions from the dialysate prior to modifying the potassium concentration through application of the electric field.

26. The method of claim 23, wherein the input fluid is a fluid removed from the dialysate flow loop at a location between an outlet of the dialysate regeneration unit and an inlet of the dialyzer.

27. The method of claim 23, wherein the potassium-modified solution is added to the dialysate flow loop at a location between an outlet of the dialysate regeneration unit and an inlet of the dialyzer.

28. The method of claim 23, further comprising operating a control or ultrafiltration pump to remove or add fluid-to or ultrafiltrate-from the dialysate flow loop downstream from the dialyzer, wherein operation of the control pump in an efflux direction causes net removal of fluid from the blood on an extracorporeal side of a membrane in the dialyzer and operation of the control pump in an influx direction causes net addition of fluid to the blood on the extracorporeal side of the membrane.

29. The method of claim 28, wherein the potassium management system is an electrodialysis cell comprising at least a concentrate flow channel, a diluate flow channel and an electrode rinse flow channel, wherein potassium ions move from the diluate flow channel to the concentrate flow channel in response to an electric field wherein the potassium-modified fluid is generated in the diluate flow channel for addition to the dialysate flow loop.

30. The method of claim 28, further comprising operating the control pump to transport ultrafiltrate through a concentrate flow channel of the potassium management system to a waste reservoir, where the potassium management system is an electrodialysis cell comprising at least a concentrate flow channel, a diluate flow channel and an electrode rinse flow channel, wherein potassium ions move from the diluate flow channel to the concentrate flow channel in response to an electric field wherein the potassium-modified fluid is generated in the diluate flow channel for addition to the dialysate flow loop.

31. The method of claim 23, further comprising and the dialysate regeneration contains a sorbent having potassium ions for cation exchange with the waste species.

32. The method of claim 23, further comprising a potassium management system that modifies the potassium concentration of the dialysate by adding the potassium-modified fluid to the dialysate flow loop.

37. The method of claim 23, wherein the method is controlled compliant.

38. The method of claim 23, wherein fluid is selectively metered into and out of the dialysate flow loop.

39. The method of claim 23, wherein the fluid is selectively metered into and out of the dialysate flow loop using any one of a control pump, a water pump, a salination pump, an acid concentrate pump, a replacement fluid pump, and combinations thereof.

40. The method of claim 23, wherein bi-directional flow is provided with the dialysate flow loop.