PH and buffer management system for hemodialysis systems
Systems and methods for managing the pH of a dialysate fluid during hemodialysis therapy. The systems and methods adjust dialysate pH and buffer concentration to generate a predetermined total bicarbonate buffer concentration in a dialysate entering a dialyzer. The systems and methods generate a pH-modifying fluid and selectively add the pH modifying fluid to the dialysate in order to accurately control the total bicarbonate buffer concentration in the dialysate entering the dialyzer.
1. A system comprising:
a dialysate flow loop for circulating a dialysate through a dialyzer,
wherein the dialysate flow loop comprises a dialysate regeneration unit having a sorbent cartridge;
a pH-buffer management system for adding or generating a pH-buffer modifying solution to the dialysate,
wherein the pH-buffer modifyinq solution has a different pH from the dialysate;
wherein the pH-buffer management system comprises a bipolar electrodialysis system for at least acidifying the dialysate;
a degasser module configured to remove at least carbon dioxide generated by the bipolar electrodialysis system; and
a controller programmed for calculating an amount of the pH-buffer modifying solution for addition to the dialysate to adjust the dialysate to be of a predetermined pH and bicarbonate buffer concentration,
wherein the controller is further programmed to determine an amount of bicarbonate generated by the dialysate regeneration unit due to a urea concentration of the dialysate upstream of the dialysate regeneration unit.
2. The system of claim 1 , wherein the pH-buffer management system comprises an infusate system configured to add a bicarbonate buffer component or unbuffered sodium bicarbonate to the dialysate.
3. The system of claim 1 , wherein the controller is programmed to determine the predetermined pH and bicarbonate buffer concentration based at least in part on an acid/base chemistry of a patient.
4. The system of claim 1 , wherein a feed into the bipolar electrodialysis system comprises an ultrafiltrate.
5. The system of claim 1 , wherein a feed into the bipolar electrodialysis system comprises a dialysate.
6. The system of claim 1 , wherein the controller is programmed to determine a pH and a buffer concentration of the dialysate to determine an addition rate of the pH-buffer modifying solution into the dialysate.
7. The system of claim 1 , wherein the controller sets an addition rate of the pH-buffer modifying solution into the dialysate at least in part based on the amount of bicarbonate generated by the dialysate regeneration unit.
8. The system of claim 1 , wherein the degasser module removes carbon dioxide undissolved within the dialysate to a certain level to achieve a specific dialysate pH.
9. The system of claim 1 , wherein the degasser module removes carbon dioxide dissolved within the dialysate to a certain level to achieve a specific dialysate pH.
10. A method comprising:
adding a pH-buffer modifying solution into a dialysate in a dialysate flow loop downstream of a dialyzer and upstream of a dialysate regeneration unit comprising a sorbent cartridge,
wherein an addition rate of the pH-buffer modifying solution into the dialysate is set to adjust the dialysate to be of a predetermined pH and bicarbonate buffer concentration;
wherein the pH-buffer modifying solution is added from a pH-buffer management system,
wherein the pH-buffer management system comprises a bipolar electrodialysis system for at least acidifying the dialysate;
determining an amount of bicarbonate generated by the dialysate regeneration unit due to a urea concentration of the dialysate upstream of the dialysate regeneration unit; and
removing, via a deqasser, carbon dioxide generated by the bipolar electrodialysis system from the dialysate.
11. The method of claim 10 , wherein the pH-buffer management system comprises an infusate system configured to add a bicarbonate buffer component or unbuffered sodium bicarbonate to the dialysate.
12. The method of claim 10 , further comprising determining the predetermined pH and bicarbonate buffer concentration based at least in part on an acid/base chemistry of a patient.
13. The method of claim 10 , wherein a feed into the bipolar electrodialysis system comprises an ultrafiltrate.
14. The method of claim 10 , wherein a feed into the bipolar electrodialysis system comprises a dialysate.
15. The method of claim 10 , further comprising determining a pH and a buffer concentration of the dialysate prior to addition of the pH-buffer modifying solution to determine an addition rate of the pH-buffer modifying solution into the dialysate.
16. The method of claim 10 , further comprising setting an addition rate of the pH-buffer modifying solution into the dialysate at least in part based on the amount of bicarbonate generated by the dialysate regeneration unit.
17. A system comprising:
a dialysate flow loop for circulating a dialysate through a dialyzer,
wherein the dialysate flow loop comprises a dialysate regeneration unit having a sorbent cartridge;
a pH-buffer management system for adding a pH-buffer modifying solution to the dialysate,
wherein the pH-buffer modifying solution has a different pH from the dialysate;
a degasser module configured to remove carbon dioxide within the dialysate to a certain level to achieve a specific dialysate pH,
wherein the degasser module is downstream from the pH-buffer management system and the sorbent cartridge; and
a controller programmed for calculating an amount of the pH-buffer modifying solution for addition to the dialysate to adjust the dialysate to be of a predetermined pH and bicarbonate buffer concentration.