In this study, patients were randomly assigned to a transfusion threshold of 9 or 7.5 g per deciliter after cardiac surgery. There was no significant between-group difference in infectious or ischemic events, but more deaths were associated with the lower threshold. Perioperative anemia is common after cardiac surgery and is associated with significant increases in morbidity and mortality. 1 – 3 The transfusion of allogeneic red cells is the preferred treatment for acute anemia and is also used in patients undergoing cardiac surgery; typically, more than 50% of patients receive a perioperative transfusion, 4 , 5 which uses a substantial proportion of blood supplies. 6 Observational studies suggest that transfusion is harmful after cardiac surgery; associations have been reported between transfusion and infection, low cardiac output, acute kidney injury, and death. 2 , 7 , 8 In contrast, randomized, controlled trials of red-cell transfusion with restrictive thresholds (i.e., transfusions . . .