Blood loss in elective coronary artery surgery: A comparison of centrifugal versus roller pump heads during cardiopulmonary bypass

Objectives: To compare the effects of centrifugal pumps verses roller pumps for cardiopulmonary bypass (CPB) in routine cardiac surgery on hematologic parameters in the context of modern practice. Design: Prospective, randomized, partially blinded. Setting: University teaching hospital. Participants: Elective coronary artery surgery patients (n = 113) Intervention: Patients were randomized to be perfused with either a roller bead (group R, n = 56] or a centrifugal head (group C, n = 57) pump. Patients received E-aminocaproic acid before and during CPB. Core body temperatures were allowed to drift down to approximately 32 degreesC. Measurements and Main Results: Postoperative chest tube blood loss, blood product requirements, hemoglobin, and platelet counts were assessed. There were no significant differences in preoperative or intraoperative parameters, including CPB time, complexity of procedure, and minimum core temperature. There were the expected reductions in hemoglobin and platelet levels post-CPB in both groups to a similar extent. Chest tubes remained in situ for similar durations, and the final volume of drainage was not significantly different (group C, 1300 +/- 92 mt; group R 1177 +/- 83 mt; p = 0.14). Allogeneic blood was given to 23% of patients in group C and 18% in group R (p = 0.63). Aspirin was associated with an increase in early chest tube drainage. Conclusions: In this surgical and perfusion environment, the authors were unable to show an advantage, from the hematologic point of view, in the routine use of a centrifugal pump head in elective coronary artery surgical patients. The use of antifibrinolytic agents and mild hypothermia may have effects on hemostasis that overshadow the influence of pump head design in this type of surgery. Copyright (C) 2001 by W.B. Saunders Company.