Bicarbonate hemodialysis using a sorbent regenerative system.

In light of the concern about the use of acetate in dialyzate a simplified means of performing acetate-free hemodialysis has been developed using the sorbent regenerative system (RED). Fifteen sorbent bicarbonate hemodialyses free of acetate were performed on two patients for 4 or 6 hours. The initial dialyzate mixture contained 135 mEq/l NaHCO3 only. The infusate cations of K, Ca and Mg were in the form of chloride salts. A 30-minute titration of the sorbent cartridge with the bicarbonate dialyzate was necessary to release the excessive hydrogen ion from the cartridge which allowed the dialyzate bicarbonate to stabilize. The dialyzate Na fell during titration but rose during dialysis. The dialyzate Cl rose throughout titration and dialyses. The plasma bicarbonate rose significantly by the end of 4 and 6 hour dialyses. The blood pO2 and pCO2 did not change during dialysis and a significant rise in blood pH resulted. We conclude that bicarbonate dialysis is feasible and relatively easily accomplished in the sorbent system.