The red cell transfusion trigger: has a sin of commission now become a sin of omission?

The benefits of a Hct range of 30 to 35 percent include improved oxygen delivery and enhanced hemostasis, which help minimize complications in patients at high risk for ischemia and perioperative nonsurgical bleeding. In these settings, the conservative transfusion practice of using a lower Hct range should be replaced with a more aggressive approach. The known risks of blood transfusion would appear to be sufficiently low and the benefits sufficiently high to justify maintaining a Hct of at least 30 percent. An even higher Hct, of 35 percent, may be desirable in patients who have overt cardiopulmonary disease or who are at high risk for myocardial ischemia. Many retrospective studies have been conducted to persuade us that a conservative transfusion trigger is a safe and prudent practice, but retrospective studies are not what we need. What we need is a series of well-designed, prospective, randomized trials to evaluate the impact of a more aggressive transfusion policy on perioperative mortality, morbidity, and nonsurgical bleeding in patients with known cardiopulmonary disease or who are at high risk for myocardial and cerebrovascular ischemia.