Hematologic studies during isolated ultrafiltration

The effect of negative-pressure isolated ultrafiltration on leukocytes, platelets, and clotting factors was evaluated in maintenance hemodialysis patients. A significant decrease in the number of leukocytes was observed during the first 45 minutes of ultrafiltration. However, by one hour, leukocyte counts had returned to pre-ultrafiltration values. A slight, persistent decrease in platelet count was also found. There was no significant change in levels of haptoglobin, free hemoglobin, or fibrinogen after one hour of isolated ultrafiltration. Levels of fibrin degradation products and fibrin monomers similarly showed no change. Heparin administration alone had no effect on the above hematological values. It is suggested that isolated ultrafiltration, as clinically practiced, has little acute effect on the coagulation system, and does not cause detectable hemolysis. The transient decrease in leukocyte count, and the modest fall in platelet count that were found are in keeping with changes previously reported to occur during hemodialysis.