Bleeding Time after Aspirin in Disorders of Intrinsic Clotting

Abstract The Ivy bleeding times before and two hours after 1 gm of aspirin in 14 patients with mild hemophilia A, 2 with mild hemophilia B, 3 with PTA deficiency, and 3 with established or suspected von Willebrand's disease (despite a normal bleeding time) did not differ significantly from those found earlier in normal controls. Mean bleeding times before aspirin were normal in 11 patients with severe hemophilia A and eight with severe hemophilia B. Four patients in each group had profoundly prolonged bleeding times after aspirin. Seven patients eventually required transfusion to stop the bleeding. The combination of aspirin and the severe clotting defect "paralyzed" the formation of the platelet aggregates that stop bleeding in the bleeding-time test, illustrating the potential therapeutic hazard of aspirin in some patients with severe hemophilia.