Abstracts of Poster Discussions and Posters; Presented at the Society of Cardiovascular Anesthesiologists; 20th Annual Meeting; Seattle, Washington; April 25-29, 1998
Introduction. Abnormal bleeding is a well-known complication following cardiopulmonary bypass (CPB). Causes of bleeding after CPB include inadequate surgical hemostasis, hypothermia, inadequate heparin reversal, fibrinolysis, and most commonly platelet dysfunction. Often patients are transfused at the clinician's discretion because results from intraoperative coagulation test results are delayed. Thromboelastography (TEG) is an established bedside monitor of coagulation which has been shown to be a better predictor of postoperative bleeding than routine coagulation studies . The purpose of this pilot study was to use TEG in an intraoperative transfusion algorithm and to determine it's ability to reduce transfusion requirements and postoperative bleeding.
Methods. After Institutional Review Board Approval, written consent was obtained from 67 patients scheduled to undergo CPB for cardiac reoperation, valvular, or combined procedures. Patients were randomized into two groups receiving intraoperative transfusions based on: (1) a TEG guided algorithm or (2) standard routine practice. All patients received intraoperative epsilon-aminocaproic acid. TEG and routine coagulation tests were sampled preoperatively and during specific intraoperative time points. Intraoperative and postoperative transfusion requirements for all blood products and postoperative mediastinal tube drainage (CTD) were recorded. All data were compared using the Student's T-test and Fisher's exact test. P<0.05 was considered significant.
Results. Thirty-three patients were enrolled in the TEG study group, and 34 were enrolled in the control group. Patients in both groups were demographically similar. There were no differences in the intraoperative transfusion rates for any blood product. However, there was a significant reduction in platelet and fresh frozen plasma (FFP) transfusions postoperatively in the TEG group (p<or=to0.05 and p=0.007 respectively). See Table 1 for all postoperative transfusion requirements and CTD.
Discussion. Our results indicate that utilization of TEG as a guide for intraoperative transfusions reduces postoperative transfusion requirements in high risk surgical patients and suggests that these patients have improved postoperative hemostasis. The use of intraoperative TEG allows for early identification and treatment of specific hemostatic defects. As a result, the empiric transfusion of allogenic blood products can be avoided.
1. Anesth and Analg 1989;69:69-75