[The demand for blood in open-heart surgery (author's transl)].

Because of the continous increase of utilization of open heart surgery, whenever possible a more conservative use of blood is desirable. During 1977, 262 consecutive patients were operated upon using the hemodilution technique of cardiopulmonary bypass. Thirtyone operative deaths occurred (11.8%) and were not related to lack of blood administration. Mean hematocrit values were 32.4% two hours after surgery and between 31 and 32.5% in the following postoperative course. Hemoglobin concentration averaged from 9.9 to 10.4 g/100 ml during the first postoperative week. The estimated amount of blood transfused averaged 872 +/- 66 ml (+/- SE) per patient. Sixtyone patients (23%) didn't receive any transfusion. A conservative attitude towards blood administration is justified by transfusion related many risks and by the current shortage of blood.