Objective: To evaluate the influence of acute autologous blood transfusion on postcardiopulmonary bypass coagulation disturbances evaluated by thromboelastography (TEG) as a point-of-care test.
Methods: This prospective randomized controlled study included consecutive patients who underwent elective cardiac surgery with cardiopulmonary bypass. The patients in group A underwent acute autologous blood transfusion with acute normovolemic haemodilution and those in group H received homologous blood, if needed, and served as controls.
Results: A total of 62 patients, from 68 enrolled, completed the study: 27 in group A and 35 in group H. Both groups had similar prolongation of prothrombin time and partial thromboplastin time, decreased platelets count and changes in postoperative thromboelastographic variables. There were no differences between them for postoperative bleeding, blood transfusions or haemoglobin values. There was significant prolongation of the R value of TEG (without heparinase) in both groups at 4 h after surgery compared with the immediate postoperative values: from 11.3 ± 4.2 to 12.3 ± 5.5 mm, P < 0.05 for group A and from 9.9 ± 3.7 to 12.5 ± 5.4 mm, P < 0.01 for group H. The R values of TEG with and without heparinase differed significantly (P < 0.05) at 4 h postoperatively.
Conclusion: Autologous blood transfusion of 15% estimated blood volume did not affect postcardiopulmonary bypass coagulopathy, nor did it decrease blood loss or homologous blood and its products transfusion in the early postoperative period. TEG is a valuable measure for detecting coagulation dysfunction with a potential role in the postoperative management of cardiac patients.