Evaluation of coagulation during cardiopulmonary bypass with thromboelastography

Objective: This study was done to evaluate coagulation function during cardiopulmonary bypass (CPB) with thromboelastography (TEG) in open heart surgery. Methods: 22 patients were studied with ACT and TEG assay before and a fter CPB. heparinase-modified TEG assays after protamine administration facilitated diagnosis of residual heparin and diminished heparin effect. Results: Except CL30, TEG values were in normal level preoperatively. After CPB, R, K and α had slightly changed, but still in normal range. TEG value of MA was significantly reduced compared with the value after protamine administration in no heparinase-modified group [(41 4±9 4) mm vs. (49 2±8 7) mm, P0 01]. MA in heparinase-modified group was greater than that in no heparinase-modified group [(44 6±9 9) mm vs. (41 4±9 4) mm, P0 05]. Heparinase eliminated residual heparin, MA was also lower compared to prebypass value (P0 01). ACT significantly correlated with the value of MA after protamine administration (r= -0 476 , P0 05), but when heparinase diminished heparin effect, the correlation disappeared. Conclusion: TEG allows for earlier diagnosis of coagulation dysfunction after cardiopulmonary bypass. It is a more sensitive predictor than ACT.