The sicker the patient, the more likely that transfusion will be beneficial

Although there is a general consensus that decisions to transfuse should not be based on hemoglobin concentrations alone (1), many people still limit blood transfusions to patients with hemoglobin concentrations less than 7 g/dL, because this strategy is easily included in a simple protocol (2). There are two conditions in which transfusions could be more liberal: one is in the presence of coronary artery disease and the other one is related to the severity of the critical illness.