An economical new process for incenter bicarbonate dialysate production: comparison with acetate in a large dialysis population.

It is generally agreed that bicarbonate dialysate is preferable to acetate dialysate, but the major limiting factors of high cost and technical difficulty in maintaining its stability for prolonged periods preclude its widespread use. The procedure developed by the authors stabilizes bicarbonate dialysate for up to 4 days, rendering bicarbonate dialysate feasible for routine out-patient use. HCO3 dialysate is produced in our dialysis unit after an initial investment of $10,000.00, at a cost per 4-h treatment of $1.22 at a dialysate flow of 500 cc/min. One hundred fifty-one chronic dialysis patients participated in an 18-week study to evaluate clinical symptomatology when bicarbonate was substituted for acetate as the dialysis base buffer. Evaluation of each dialysis treatment (total of 8,183 treatments) consisted of both subjective and objective criteria (vomiting, angina, cramps, hypotension, and frequency of use of mannitol, hypertonic saline, and nitroglycerine). The patients were unaware of the change in dialysate solutions. There was a significant reduction (p less than 0.001) in the incidence of vomiting, cramps, hypotension, nausea, flushing, and the use of mannitol and hypertonic saline during bicarbonate dialysate treatment compared with acetate dialysate. Shortness of breath, angina, mental confusion, and paresthesias were not statistically changed. Although the method of HCO3 dialysate production is associated with occasional higher bacterial count than currently recommended by AAMI standards, no adverse reactions were observed in patients treated with standard efficiency dialyzers. It is concluded that the process for incenter HCO3 production is safe, economical, and better tolerated than acetate dialysate.