• Journal of Chest Surgery
• /
• v.30 no.7
• /
• pp.677-685
• /
• 1997

Thromboelastography(TEG) is the unique measure that gives rapid information about the whole clotting process. Simplifying the diagnosis of coagulopathy during operations, TEG can provide an adequate therapy for postoperative bleeding. Remarkable improvement in hemostasis after cardiopulmonary bypass(CPB) has been achieved by the treatment with proteinase inhibitor aprotinin, but the hemostatic mechanism of aprotinin during CPB is still unclear. This study was designed to evaluate the effects of aprotinin on coagulation system during CPB by using TEG. Forty patients who underwent CPB were divided into two groups: aprotinin(2u 106 kallikrein inhibition units, as a single dose into the cardiopulmonary bypass priming solution) treatment group(male 14, female 8, mean age=50.Byears) and no aprotinin treatment(control) group(male 10, female 8, mean age=53.4 years). TEG, activated clotting time, prothrombin time, activated partial thromboplastin time, platelet counts, fibrinogen an (ibrinogen degradation product(FDP) concentrations were checked before and after CPB(30 minutes after neutralization of heparin effect by protamine sulfate). There was no significant difference in other conventional coagulation tests of two groups except postcardiopulmonary bypass FDP concentration in control group, which was significantly increased compared to that in aprotinin group(p<0.05). In TEG variables of both groups, clot formation time(K) and alpha $angle(\alpha^{\circ})$ were significantly increased and decreased, respectively, after CPB(p<0.05), but fibrinolytic index(LYS60) was not changed during CPB. In aprotinin group, reaction time(R) was decreased significantly after CPB(p<0.05) but maximum amplitude(MA) was not changed(p>0.05). On the contrary, R was not changed markedly but MA was decreased significantly in control group after CPB(p<0.05). This result shows that main change in coagulation system during CPB is not hyperfibrinolysis but cecrease in clot strength by platelet dys unction, and the main effect of aprotinin during cardiopulmonary bypass is the maintenance of clot strength to the pre-CPB level by the preservation of platelet function.

• Journal of Chest Surgery
• /
• v.30 no.11
• /
• pp.1092-1096
• /
• 1997

Thromboelastography(TEG) enables a global assessment of hemostatic function to be made from a single blood sample, documenting the interaction of platelets with protein coagulation cascade from the time of the initial platelet-fibrin interaction, through platelet aggregation, clot strengthening and fibrin cross linking to eventual clot Iysis. Thirty-five patients(mean age 34$\pm$ 12) undergoing open heart surgery from April 1st, 1996 to August 31th, 1996 were investigated at preoperatively and immediate, one hour, and 24 hours after cessation of cardiopulmonary bypass using TEG. Comparisons were made between classic hematological indices and TEG data. There were statistically significant correlation between maximal amplitude(MA) and platelet count before CPB, activating clotting time(ACT) and TEG date(R time, K time and a angle) at 24-hour after CPB. The data on the predictive accuracy for postoperative bleeding at 24-hour after CPB, the TEG was significantly better than ACT(57%) or the coagulation profiles(43%) as a predictor of postoperative bleeding, with an accuracy rate of 100% (P=0.0043). In conclusion, TEG seems to be easy to use, clinically accurate, cost effective and provides data which can effectively manage a patient's hemostasis.