The Change of Platelet Function during Pediatric Open Heart Surgery

Kim, Chong Sung; Kim, Yong Lack

Abstract

To evaluate the change of platelet function during pediatric open heart surgery, authors measured CBC(hemoglobin, hematocrit, platelet count), bleeding time, activated clotting time (ACT), and the degree of platelet aggregation immediately after induction(Tl), after arrival at intensive eare unit (ICU)(T2) and 24 hours after operation(T3) separately. The patients were devided into two groups; one group (7 patients, DHCA(-) group) was not undergone deep hypothermic circulatory arrest(DHCA) and the other group (7 patients, DHCA(+) group) was undergone DHCA. Authors analized the differences between two groups(intergroup) and between pre-CPB and post-CPB values(intragroup). The correlations between the degree of platelet aggregation and platelet count, body temperatue, period of cardiopulmonary bypass (CPB), and hleeding time were also analized respectively. The results were as follows, 1) The age, weight, body surface, and the nadir of body temperature during CPB, except the period of CPB, were significantly different between two groups. The average period of DHCA was 53.7+/-7.5 minutes. The average nadir of rectal and esophageal temperature were 17.2+/-1.1 degrees C and 14.0+/-0.9 degrees C in DHCA(+) group. 2) Intergroup and intragroup differences were not significant in hemoglobin and hematocrit. 3) Intragroup differences in platelet count were significant but intergroup difference were not significant. 4) The percent changes of platelet aggregation at T2 and T3 compared to the value at Tl were 70-80%, and 80-90% respectively. 5) The correlations between the degree of p1atelet aggregation and temperature, period of CPB, platelet count and bleeding time were poor, but bleeding time correlated with platelet count(r=0.6, P< 0.05).