Hematologic and Coagulation Measurements in Autotransfused Blood
Reinfusion of blood shed during elective or emergency vascular surgery (autotransfusion) is an under utilized technique. This is due in part to doubts as to the quality of autotransfused blood and concern about the risk of inducing a coagulopathy in the recipient. We have measured coagulation and hematologic parameters in autotransfused blood in the recipient before and at intervals after operation in 62 patients, none of whom received bank blood or blood products at the time of the study. The patients were heparinized (3 mg/Kg) during operation and this was reversed by protamine at the end of the procedure. The salvaged blood was reinfused immediately after appropriate samples had been taken. The mean volume of blood autotransfused was 1.8L in 58 patients and 9.4L in 4 patients. There was excellent preservation of platelets and fibrinogen, normal levels being maintained both in the autotransfused blood and in the recipients. Values for fibrin degradation products and euglobulin clot lysis remained normal. The mean plasma hemoglobin in the autotransfused blood was 416 mg% and this was not correlated to the volume autotransfused. Partial thromboplastin time which was prolonged by heparin during surgery was consistently normal post-operatively. No patient developed complications which could be attributed to autotransfusion and, in particular, re-operation for post-operative bleeding was never required and wound hematoma was not seen. We conclude that autologous blood may be returned to patients in large amounts without significant risk using the technique described. The technique deserves wider application in major surgery.