• Objective To review the literature on the limitations and consequences of packed red blood cell transfusions, with particular attention to critically ill patients.
• Methods The PubMed database of the National Library of Medicine was searched to find published articles on the indications, clinical utility, limitations, and consequences of red blood cell transfusion, especially in critically ill patients.
• Results Several dozen papers were reviewed, including case series, meta-analyses, and retrospective and prospective studies evaluating the physiological effects, clinical efficacy, and consequences and complications of transfusion of packed red blood cells. Most available data indicate that packed red blood cells have a very limited ability to augment oxygen delivery to tissues. In addition, the overwhelming preponderance of data accumulated in the past decade indicate that patients receiving such transfusions have significantly poorer outcomes than do patients not receiving such transfusions, as measured by a variety of parameters including, but not limited to, death and infection.
• Conclusions According to the available data, transfusion of packed red blood cells should be reserved only for situations in which clear physiological indicators for transfusion are present.
Red Blood Cell Transfusion Thresholds in Critically Ill Patients
