The new AN69 membrane in biofiltration (BF): 18 month's follow-up.

BF is a dialytic procedure employing the new AN69 polyacrylonitrile membrane, which is more permeable to both water and solutes than the traditional AN69. A postdilutional bicarbonate infusion is necessary in BF. The treatment time is 3 hours. Six patients, previously on regular acetate (HD) or bicarbonate dialysis (BHD) with AN69 were treated for 18 months with BF. Biochemical and hematological parameters (BUN, creatinine, uric acid, CA, P, K, Na, blood pH, HCO3, hematocrit) and clinical signs were evaluated in BF, and compared to those of HD and BHD. An improvement in biochemical and hematological parameters accompanied by better clinical signs was seen in BF as compared to HD and BHD. In our opinion this is due both to better removal of small and middle molecules and the bicarbonate infusion, and to the shorter dialytic session.