Off-pump CABG is potentially associated with reduced intraoperative blood loss and homologous blood transfusion in comparison to on-pump CABG. In this randomised controlled study we investigated the effects of autologous cell saver blood transfusion on blood loss and homologous blood transfusion requirements in patients undergoing CABG on- versus off-CPB.Methods:
Eighty patients were randomised into one of four groups: (A) on-CPB with cell saver blood transfusion (CSBT), (B) on-CPB without CSBT, (C) off-pump with CSBT and (D) off-pump without CSBT. Volume of intraoperative autologous blood transfusion, postoperative mediastinal blood loss and homologous blood transfusion requirements were measured. Homologous blood was transfused when haemoglobin concentration fell below 8 g/dl postoperatively. Pre- and postoperatively prothrombin time and partial thromboplastin time were measured.Results:
Preoperative patient characteristics were well matched among the four groups. The amount of salvaged mediastinal blood available for autologous transfusion was significantly higher in the on-pump group (A) compared to the off-CPB group (C) (433 ± 155 ml vs 271 ± 144 ml, P = 0.001). Volume of homologous blood transfusion was significantly higher in group B vs groups A, C and D (595 ± 438 ml vs 179 ± 214, 141 ± 183 and 230 ± 240 ml, respectively, P ≪ 0.005). The cell saver groups (A and C) received significantly less homologous blood than the groups without cell saver (160 ± 197 ml vs 413 ± 394 ml, respectively, P ≪ 0.005). Patients undergoing off-CPB surgery received significantly less homologous blood than those undergoing on-CPB CABG irrespective of cell saver blood transfusion (184 ± 214 ml vs 382 ± 397 ml, P ≪ 0.05). Postoperative blood loss was similar in the four groups (842 ± 276, 1023 ± 291, 869 ± 286 and 903 ± 315 ml in groups A to D, respectively, P > 0.05). Clotting test results revealed no significant difference between the groups. There was no significant difference in postoperative morbidity between groups.Conclusion:
Off-pump CABG is associated with significant reduction in intraoperative mediastinal blood loss and homologous transfusion requirements. Autologous transfusion of salvaged washed mediastinal blood reduced homologous transfusion significantly in the on-CPB group. Cell saver caused no significant adverse impact on coagulation parameters in on- or off-CPB CABG. Postoperative morbidity and blood loss were not affected by the use of CPB or autologous blood transfusion. We recommend the use of autologous blood transfusion in both on- and off-pump CABG surgery.