Haemodialysis-membrane biocompatibility and mortality of patients with dialysis-dependent acute renal failure: a prospective randomised multicentre trial

Background There is controversy as to whether haemodialysis-membrane biocom patibility tie, the potential to activate complement and neutrophils) influ ences mortality of patients with acute renal failure. We did a prospective randomised multicentre trial in patients with dialysis-dependent acute rena l failure treated with two different types of low-flux membrane. Methods 180 patients with acute renal failure were randomly assigned bioinc ompatible Cuprophan (n=90) or polymethylmethacrylate (n=90) membranes. The main outcome was survival 14 days after the end of therapy (treatment succe ss). Odds ratios for survival were calculated and the two groups were compa red by Fisher's exact test. Analyses were based on patients treated accordi ng to protocol (76 Cuprophan, 84 polymethyl methacrylate). Findings At the start of dialysis, the groups did not differ significantly in age, sex, severity of illness las calculated by APACHE II scores), preva lence of oliguria, or biochemical measures of acute renal failure. 44 patie nts (58% [95% CI 46-69]) assigned Cuprophan membranes and 50 patients (60% [48-70]) assigned polymethyl-methacrylate membranes survived. The odds rati o for treatment failure on Cuprophan compared with polymethyl-methacrylate membranes was 1.07 (054-2.11; p=0.87). No difference between Cuprophan and polymethyl-methacrylate membranes was detected when the analysis was adjust ed for age and APACHE II score, 18 patients in the Cuprophan group and 20 i n the polymethyl-methacrylate group had clinical complications of therapy ( mainly hypotension). Interpretation There were no differences in outcome for patients with dialy sis-dependent acute renal failure between those treated with Cuprophan memb ranes and those treated with polymethyl-methacrylate membranes.