Continuous Ambulatory Peritoneal Dialysis with Bicarbonate Buffer-A Pilot Study

I deally, peritoneal dialysate as well as hemodialysis dialysate should be physiological in constitution and concentration. Lactate is the commonly used buffer in continuous ambulatory peritoneal dialysis (CAPD) solutions. In the commercially available CAPD solutions, unphysiological values of pH and unphysiological concentrations of lactate and glucose were demonstrated to affect the peritoneal membrane (1), the viability of mesothelial (2) and resident peritoneal cells (3), and to inhibit phagocytic functions (3-5). Lactate infusion, in particular, has been proved to affect many vital cellular functions and to have catabolic and other systemic side effects (6). In addition, the standard 35 mmol/L lactate CAPD solutions do not provide a full correction of metabolic acidosis (7) enhancing the catabolic state of uremic patients (8). By increasing the lactate concentration of the solutions to 40 mmol/L, the acid base status of the patients does not always improve, and lactate serum levels probably exceed the normal values (9,10). Bicarbonate is the physiological buffer of the body, but CAPD solutions containing bicarbonate could not be produced in the past because of calcium carbonate precipitation. This problem has been solved by using a new double-chamber bag with separate compart ments for acid and bicarbonate-containing solutions (11). The two solutions were directly mixed inside the bag just before use, and a final dialysate with a pH in the physiological range was obtained. The main purpose of this short-term clinical study is to assess the efficacy, adequacy, clinical tolerance, and safety of peritoneal dialysis solution with 34 mmol/L of bicarbonate as a buffer substance in CAPD patients.