• Rationale and Comments

    The Canadian Transfusion Requirements in Critical Care trial was the first to investigate a liberal versus restrictive approach to RBC transfusions. The trial included a total of 838 hemodynamically stable, critically ill patients who had a hemoglobin concentration less than 9 g/dL (adult transfusion trigger 7g/dL to 8 g/dL). The trial defined two categories for the study, a “liberal” approach that required allogeneic RBC transfusions for patients with hemoglobin less than 10 g/dL and a “restrictive” approach for patients with a hemoglobin concentration less than 7 g/dL. Patients were randomly divided between both study groups and were evaluated at 30 days. There was no significant mortality difference. The trial also noted a significantly better survival rate among patients younger than 55 years old within the restrictive group, particularly less acutely ill patients. Subsequent studies have shown that clinically stable patients may benefit more from a restrictive approach by reducing the percentage of patients exposed to allogeneic RBCs. It is not recommended to transfuse RBCs as the sole intervention for volume expansion. The World Health Organization recommends volume-expanding solutions such as crystalloids or colloids to expand fluid volume. These promote blood circulation through vital organs and tissues. RBC transfusions should be used to treat conditions such as severe hemorrhage that otherwise lead to significant mortality. Recent evidence for blood transfusions suggests that a restrictive transfusion approach is safer and as effective as a liberal approach for postoperative stable patients, normovolemic critically ill patients with a hemoglobin transfusion trigger of 7g/dL to 8 g/dL, and patients with clinical symptoms of anemia. The exception to the restrictive approach is comprised of patients with clinically significant cardiovascular conditions. Blood products carry the risk of transmitted infectious diseases and adverse effects of blood transfusion (e.g., immunosuppressive complications).

    Sponsoring Organizations

    • American Society for Clinical Laboratory Science


    • Randomized controlled trials


    • Hematologic


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