[Clinical aspects of packed red cell transfusion. Lessons learned from Jehovah's Witnesses?].

With the decreased risk of homologous blood transfusions, the costs of blood products have become increasingly important for hospitals with major surgical procedures and oncologic treatment. It is well established from clinical physiology that a hemoglobin concentration (cHb) lower than 6.21 mmol/l (10 g/dl) is enough to serve the oxygen demand of the tissues, but transfusion of erythrocytes is still liberally carried out. Data obtained from Jehovah's Witnesses, who categorically refuse blood transfusions, demonstrate that they have an outcome similar to patients who are transfused. The lessons we have learned from Jehovah's Witnesses should result in an emotionless discussion, and a reduction in transfusion requirements.