Update on Blood Conservation for Cardiac Surgery

PATIENTS UNDERGOING CARDIAC SURGERY are at risk of excessive bleeding, leading to increased usage of allogeneic blood and hemostatic blood products. Although this patient population represents a relatively small proportion of surgical patients, cardiac surgery consumes about 20% of the available blood supply in the United States,1 with similar numbers reported worldwide.2,3 The potential for beneficial effects of transfusing blood to maintain tissue oxygen perfusion and prevent organ ischemia may be greatest in patients with cardiovascular disease.4 Indeed, life-threatening hemorrhage, an absolute indication for blood transfusion, may be relatively frequent in these patients, with repeat surgery for bleeding occurring in up to 5% of patients.5,6 In addition, the risks of preexisting anemia and acute perioperative hemodilution have become more apparent.7,8 However, there is a lack of clinical outcome data to support the liberal use of blood transfusion in cardiac surgery.