Platelet Function in Recipients of Platelets from Donors Ingesting Aspirin

The effect of fresh platelet transfusions from donors ingesting aspirin was evaluated in a group of thrombocytopenic recipients. Prolonged bleeding times were corrected to normal in recipients of platelets from donors who had taken aspirin 36 hours before donation, but not in those receiving platelets from donors who had taken aspirin within 12 hours of donation. In healthy volunteers, the abnormalities induced by aspirin ingestion on the bleeding time and epinephrine-induced platelet aggregation disappeared by 72 hours after ingestion. Analysis of the data indicates that when approximately 20 per cent of the circulating platelets have not been exposed to aspirin, the hemostatic function of the platelet pool is maintained. Thus, widespread use of aspirin should not present a serious problem in the selection of platelet donors.