Risk factors for red blood cell transfusion after coronary artery bypass graft surgery.

Objectives: Perioperative transfusion of red blood cells is associated with increased morbidity and mortality. The authors investigated the correlation between preoperative risk factors and the number of red blood cell units received in patients undergoing coronary artery bypass graft surgery. Design: A retrospective analysis of prospectively collected data. Setting: A single-center study performed in an educational hospital. Participants: All patients who underwent isolated coronary artery bypass graft surgery between 1998 and 2007 (N = 10,626) were included. Interventions: Isolated coronary artery bypass graft surgery. Measurements and Main Results: Univariate and multivariate logistic regression analyses were performed to investigate the impact of preoperative and perioperative factors on transfusion of 1 or more units of red blood cells. The following independent risk factors for receiving red blood cell units were identified: age, female sex, low body surface area, low left ventricular ejection fraction (<35%), emergency operation, previous cardiac surgery, low preoperative hemoglobin, and low preoperative creatinine clearance. Perioperative risk factors were the use of extracorporeal circulation, longer bypass time, use of crystalloid cardioplegia, the need for intra-aortic balloon pump, perioperative myocardial infarction, and re-exploration for any cause. Conclusions: In this study, the authors identified risk factors for receiving red blood cells in patients undergoing coronary artery bypass graft surgery. The authors were able to implement these factors in their daily practice by sharpening the criteria for the direct availability of red blood cells in the operating room.