Observational studies have suggested that older red blood cells may negatively affect patient outcomes. Results from a multicenter, randomized, controlled trial recently published in The New England Journal of Medicine, however, suggest that fresh red blood cells (RBCs) do not improve outcomes in critically ill patients.
In the Age of Blood Evaluation (ABLE) trial, 1211 critically ill patients were assigned to receive fresh RBCs (mean storage time of 6.1 days) while 1219 patients received standard-issue RBCs (mean storage time of 22.0 days). Enrollment characteristics and number of RBC units transfused during the trial were similar in both groups. The 90-day mortality was equivalent in both groups; 37.0% (448/1211) of patients in the fresh-blood group and 35.3% (430/1219) in the standard-blood group died. In addition, no differences were found for any secondary outcomes including major illness, length of hospital stay, or transfusion reactions. Further studies are needed to ensure that red cells stored for very long periods do not affect patient outcomes.
1. Lacroix J, Hebert PC, Fergusson DA, Tinmouth A, Cook DJ, Marshall JC, Clayton L, McIntyre L, Callum J, Turgeon AF, Blajchman MA, Walsh TS, Stanworth SJ, Campbell H, Capellier G, Tiberghien P, Bardiaux L, van de Watering L, van der Meer NJ, Sabri E, Vo D, Investigators A, the Canadian Critical Care Trials G. Age of Transfused Blood in Critically Ill Adults. N Engl J Med 2015.