Which of the following is/are acceptable reasons for the transfusion of red blood cells based on currently available data?

A. Rapid, acute blood loss with unstable vital signs but no available hematocrit or hemoglobin determination.

B. Symptomatic anemia: orthostatic hypotension, severe tachycardia (greater than 120 beats per minute), evidence of myocardial ischemia, including angina.

DISCUSSION: Currently accepted guidelines for the transfusion of packed red blood cells include acute ongoing blood loss, as might occur in an injured patient, and the development of symptomatic anemia with manifestations of decreased tissue perfusion related to decreased oxygen-carrying capacity of the blood. This includes situations in which the patient is unable to compensate for a decreased oxygen-carrying capacity by the usual mechanisms, such as increased cardiac output. Such patients develop myocardial dysfunction if an excessive demand is placed on the heart. The patient should be transfused with packed red blood cells, which afford added oxygen-carrying capacity. This decreases the workload on the myocardium while providing the necessary oxygen-delivery capability. The use of packed red blood cells to improve wound healing or to improve the patient's sense of well-being is highly questionable. No data support such a practice. In general, the use of a transfusion trigger such as a hematocrit of 30% or hemoglobin of 10 gm. per dl. constitutes a questionable indication for transfusion. If a patient is asymptomatic and stable and has no risk of myocardial ischemia, packed red blood cell transfusion should not be given based solely or predominantly on a numerical value such as a hematocrit of 28%.