Blood conservation in cardiac surgery: guidelines and controversies.

Bleeding related to cardiac surgery is an important clinical problem. Perioperative anemia and transfusion of allogeneic blood products have both been associated with adverse outcome including mortality and major morbidity. Guidelines exist to help determine when the risks of anemia outweigh the risks of transfusion. Perioperative bleeding may be related to several factors including the use of new antithrombotic drugs. A variety of hemostatic drugs have been studied to reduce bleeding and transfusion, although several questions and concerns about them exist. Patient blood management programs can be valuable for management of patients undergoing cardiac surgery.