Red cell age and loss of function: advance or SNO-job?

摘要

Transfusion of red blood cells (RBCs) is one of the oldest, most trusted, but least scientific of medical practices-least scientific because the practice is not supported with the kind of clinical data showing efficacy and safety that would be required by any new therapeutic measure. Underlying the decision to transfuse a patient is the assumption that more hemoglobin (Hb) means more O_2 available to hypoxic or ischemic tissues. Recently, traditional "transfusion triggers" have been questioned,1 and more conservative transfusion criteria have been associated with improved overall clinical outcome in surgical patients. Because the idea that transfusions may be potentially harmful runs counter to traditional practice and intuition, the possibility has been raised that stored RBCs, known to differ significantly from fresh blood, might be less safe#