ABSTRACT
To investigate the effects of cardiopulmonary bypass (CPB)on the aquired platelet damage and the relationship between the aquired platelet damage and non-surgical postoperative bleeding. Method: Platelet counts (BPC), alphagranule membrane protein (GMP-140), ?-thromboglobulin (?-TG), platelet factor 4 (PF_4), and 5-hydrooxytryptamine levels were measured in 20 patients undergoing cardiac surgery before CPB, 30 min during CPB, 10 min after CPB, and 2, 12, and 24 hours postoperatively. The numbers of patients with bleeding volume over 200 ml within 24 hours postoperatively were counted. Result: BPC decreased markedly during CPB, but never decreased to the degree of 50?10~9/L. GMP-140, ?-TG, PF_4 and 5-HT levels were significantly increased during CPB until 12 hours postoperatively. Eight patients(40%) got the bleeding volume over 200 ml within 24 hours postoperatively. Conclusion: Platelet release reaction is violent during cardiac surgery with CPB. A large number of platelets dysfunctioned because of granula releasing or damage may be the main cause of non-surgical postoperative bleeding.