Most patients followed a restrictive transfusion trigger of Hb <8 g/dl.A less restrictive trigger of Hb <9 g/dl was used for patients with active cardiac disease or acute anemia symptoms.This transfusion protocol was consistently applied by anesthesiologists and surgeons throughout the hospital stay, including in the operating theater, anesthesia recovery unit, and wards. Here, GSTM1 is linked to anemia (phenotype).