Hopewell and colleagues performed a systematic review of observational studies published between 2006 and 2010 on the impact of red blood cell transfusion on mortality. The authors identified 32 studies that included over 1000 patients. Most studies found higher death rates in transfused patients, even after adjusting for potential confounding variables. However, the authors note that it is uncertain if these studies adequately adjusted for differences between patients transfused and not transfused.

– Jeffrey L. Carson