Heparinization control by activated coagulation time in cardiac surgery with extracorporeal circulation

The authors studied 20 patients undergoing cardiac surgery with extracorporeal circulation using a protocol proposed by Bull for the control of heparinization using the activated coagulation time of whole blood proposed by Hattersley. The patients, alterations in the coagulation and in red cell values were evaluated comparing the pre-operatory values with the post-operatory ones. The activated coagulation time (ACT) was evaluated as to its variability in different periods (pre, trans, and post-surgery). All the results were compared with world literature. They conclude that it is an excellent method for the control of the monitoring of heparin therapy and neutralization with protamine sulfate, which was used in lower doses than those referred to in literature. No post-operatory complications due to alterations in the coagulation system were observed. The total doses of heparin and protamine per kilogram were, respectively, 5.85 mg and 4.34 mg. There was significant variation between the erythrocytes, the hemoglobin and the platelets (p less than 0.001). As to the prothrombin time, the partial thromboplastin time, the coagulation time and the fibrinogen, none showed significant variation. The ACT did not show significant variation between the values obtained during perfusion, and neither between the basal value and the value post-protamine, the basal and the 30 minutes post-protamine, and the post-protamine and 30 minutes post-protamine.