Which intraoperative transfusion threshold applies to stable adults?

• A. Hb <9 g/dL.
• B. Hb <7 g/dL; higher threshold for cardiac disease or major risk.
• C. Hb <10 g/dL.
• D. Transfusion thresholds are never based on Hb.

Answer: (B)

A restrictive transfusion approach is used for stable adults, meaning we transfuse only when hemoglobin drops to a level that may impair oxygen delivery. The usual trigger is a hemoglobin level below 7 g/dL. If the patient has cardiac disease or major risk factors for ischemia, the threshold is raised—often around 8 g/dL—to safeguard myocardial oxygen supply. Intraoperative decisions also weigh ongoing blood loss and perfusion, but the Hb concentration is the main guide. Lower thresholds (like 9 or 10 g/dL) would lead to more transfusions without added benefit in stable patients, and transfusion decisions are indeed driven by Hb with adjustment for cardiovascular risk. Therefore, the described threshold of Hb below 7 g/dL, with a higher threshold for cardiac disease or major risk, fits best.