"Despite the perceived benefits of transfusion, research has indicated that exposure of allogeneic blood is associated with increased risks of morbidity and mortality following cardiac surgery. Adverse postoperative clinical outcomes - such as renal failure, stroke, pulmonary dysfunction and infections - have been reported. While these complications have been linked to as few as 1-2 units of donor RBCs, the impact on patient outcome is believed to be dose-dependent. Additionally, the transfusion consequences may extend beyond hosptalization and influence long-term survival," David C. Fitzgerald and Joseph J. Sistino (Medical University of South Carolina, Charleston/USA) report in the new textbook "Extracorporeal Circulation in Theory and Practice".