Clinical evaluation of a dialysate regeneration system for maintenance haemodialysis.

A commercially available sorbent-based dialysate regeneration system has been compared to conventional single-pass dialysate delivery systems for treatment periods of six weeks in 13 patients on maintenance dialysis. The results of treatment were virtually identical in comparing sorbent and conventional systems except that seven of the eight patients using 2-5 M2 dialysers for 3--4 hours thrice per week developed asymptomatic metabolic acidosis with the dialysate regeneration system. This complication was not seen in the five patients using 1-3 M2 dialysers and having a 6--7 hour treatment thrice weekly. Dialysate regeneration systems are particularly suited for use when water supplies are limited or of insufficient purity for single-pass dialysis, and when a portable artificial kidney is required. To avoid metabolic acidosis with this system, using currently available disposable cartridges, each dialysis treatment should be of at least 4-5 hours duration.