Rohde et al. performed a meta-analysis comparing hospital-acquired infections from 7,500 patients enrolled in 18 randomized trials. They found rates of hospital-acquired infections were 16.9% in the liberal transfusion group and 11.8% in the conservative transfusion group (risk ratio = 0.82; 95% CI, 0.72-0.95). When the restrictive transfusion threshold was set at less than 7.0 g/dL, the number needed to treat was 20, indicating that one patient could potentially avoid an infection out of every 20 patients treated. The reduced risk of infection remained even among individuals who received leukocyte reduced RBCs. More studies are needed to determine the optimal threshold for restrictive RBC transfusion strategies.
2. Rohde JM, Dimcheff DE, Blumberg N, et al. Health care-associated infection after red blood cell transfusion: a systematic review and meta-analysis. JAMA : the journal of the American Medical Association 2014; 311(13): 1317-26.