Low thrombogenicity of polyethylene glycol-grafted cellulose membranes does-not influence heparin requirements in hemodialysis

Heparin is the most commonly used anticoagulant for hemodialysis despite po tentially serious side effects. Polyethylene glycol-grafted cellulose (PGC) membranes produce less activation of the coagulation cascade than cupropha ne membranes. Anecdotally, we found some patients required a surprisingly l ow level of anticoagulation using these membranes, We compared the anticoag ulant requirement of the PGC membrane with that of the cuprophane membrane in this randomized, prospective, crossover study. Sixty-three patients were randomized to treatment using either membrane, and heparin administration was progressively reduced to the lowest dose that prevented visible cloning in excess of that normally encountered. Patients underwent dialysis at thi s dose for 1 month, after which the heparin requirement and Kt/V-urea (1.16 2 x In [urea pre/urea post]) were assessed. This process was then repeated for each patient using the other membrane, and the results were compared. H eparin administration during dialysis was reduced from a mean loading dose of 29.0 +/- 9.4 to 1.5 +/- 3.2 IU/kg for both membranes and a mean maintena nce infusion of 14.0 +/- 6.7 to 0.77 +/- 1.6 IU/kg/h for both membranes (bo th P < 0.0001 v full anticoagulation; no difference between membranes). The Kt/V-urea was not significantly altered. Forty-six patients with PGC and 4 5 patients with cuprophane membranes underwent dialysis successfully withou t heparin during dialysis, and the other patients were using considerably r educed doses. Aspirin and warfarin had no effect on the heparin requirement . These results do not support the theory that PGC membranes have a lower a nticoagulant requirement than cuprophane membranes; however, they suggest t hat dialysis can be performed successfully with much smaller anticoagulant doses than are currently in common use. (C) 1999 by the National Kidney Fou ndation, Inc.