RESUMO
This study was conducted to determine the use of thromboelastograph in predicting excessive postoperative bleeding, detecting coagulopathy related bleeding, reducing usage of blood and blood products and aiding reexploration decisions. One hundred fifty patients undergoing coronary artery bypass graft surgery under cardiopulmonary bypass were randomized and studied prospectively in two equal groups. In the study group, celite activated heparinase pretreated blood samples, 30 minutes after protamine administration were subjected to thromboelastographic analysis and blood and blood component therapy was administered based on thromboelastograph values, if they had significant bleeding. In the control group transfusion therapy was based on routine coagulation tests and clinical judgement of the surgeon. Patients who bled 100ml / hour in the first three hours or 300 ml in the first three hours and 75 ml/hour in the next three hours were considered significant bleeders. Haematocrit at 0,6,12,18,24,30 and 36 hours of shifting to intensive care unit were noted. Accuracy of thromboelastograph in predicting excess postoperative bleeding was found to be 92%. Consumption of whole blood, packed red blood cells and fresh frozen plasma (p values 0.03, 0.05, 0.001 respectively) was significantly less in the study group. There was poor correlation between postoperative bleeding and platelet count but those who did not bleed had a significantly higher platelet count as compared to those who did. Except at 30 hours, haematocrit was significantly higher in the study group up to 36 hours. Thromboelastograph is a useful diagnostic tool to detect coagulopathies following cardiopulmonary bypass. It helps in instituting appropriate blood and blood component therapy thereby avoiding unnecessary transfusion and associated risks. Accurate detection of coagulopathy is possible with heparinase pretreatment of the blood sample.