Dialysis leukopenia, hypoxemia, and anaphylatoxin formation: effect of membrane, bath, and citrate anticoagulation

The goal of these prospective studies was to determine the effect of different dialyzer membranes and dialysate composition on leukopenia and hypoxemia during hemodialysis with citrate anticoagulation. Significant early leukopenia was found with a cuprophane membrane, while a cellulose acetate membrane was associated with mild early leukopenia. Bath composition had no effect. Bicarbonate dialysate, compared with acetate, eliminated hypoxemia in cellulose acetate membranes and reduced its degree and duration with cuprophane. Membrane composition had no effect on hypoxemia during acetate dialysis. The findings indicate that leukopenia is directly and exclusively related to membrane composition while hypoxemia only relates in part to membrane effects. Serial determinations of complement components C3a and C5a showed significant increases in parallel with leukopenia during heparin anticoagulation, but the anaphylatoxin concentration changes were dissociated during dialysis with citrate anticoagulation. The concentrations of anaphylatoxins C3a and C5a appear not to be directly related to dialysis-induced leukopenia. The dissociation between anaphylatoxin concentrations and leukopenia may be related to changes in generation or unmasked changes in leukocyte response. Citrate anticoagulation may provide a useful probe for further studies on membrane-leukocyte interactions in vivo.