Risks of packed red blood cell transfusion in patients undergoing cardiac surgery

Packed red blood cell (PRBC) transfusion is common in patients undergoing cardiac surgery. Evidence has accumulated demonstrating that such patients can tolerate relatively low hemoglobins, and an extensive body of literature has developed demonstrating that patients undergoing such surgery who receive PRBC are at risk for several adverse outcomes including increased mortality, atrial fibrillation, and more postoperative infections, as well as numerous other complications. The PubMed database was searched for the English language literature on the topic of PRBC transfusion and outcomes in patients undergoing cardiac surgery, as well as alternatives to this intervention. Data were reviewed to assess the impact of transfusion in patients undergoing cardiac surgery on mortality, cardiac, infectious, and pulmonary, as well as a variety of miscellaneous complications. Patients receiving PRBC were consistently identified as being at higher risk for complications in all categories. The limited prospective data were consistent with the retrospective data, which comprised most of the literature. The preponderance of the literature suggests that patients undergoing cardiac surgery can tolerate lower hemoglobin/hematocrit values than traditionally appreciated. Most published data also indicate that PRBC transfusion should be reserved for patients with an identifiable clinical/physiologic indication fir this intervention, consistent with recent specialty society guidelines.