Postoperative platelet function in patients on small subcutaneous doses of heparin

Several platelet function tests were performed on 31 patients undergoing major operations, who recieved prophylactically small subcutaneous doses of heparin. A group of 15 similar patients without heparin served as controls. It was found that postoperatively in both groups (a) the platelet retention in glass bead column was significantly increased (p less than 0.001), (b) the platelet aggregation by ADP 1 micronM was slightly increased, (c) the collagen-induced aggregation, ADP release and the bleeding time remained unchanged and (d) the platelet counts decreased in the first 2 postoperative days and increased thereafter. There was no difference between patients on heparin and controls.