This study analyzed 45 observational studies including over 272,000 patients to determine the association between red blood cell transfusion and morbidity and mortality in high-risk hospitalized patients. The analysis found that in 42 of the 45 studies, the risks of red blood cell transfusion outweighed the benefits, with transfusion associated with increased risk of death, infections, multi-organ dysfunction syndrome, and acute respiratory distress syndrome. A meta-analysis found that transfusion was associated with 70% higher odds of death and 80% higher odds of developing an infectious complication. The study suggests current transfusion practices may need reevaluation given the risks appear to outweigh the benefits in most patients.