[Need for transfusions in orthognathic surgery. No general indication for preoperative autologous blood donation].

The use of deposited autologous blood instead of allogenic blood is recommended in cases of elective maxillofacial operations if the blood transfusion probability is more than 10%. As an alternative, the controlled intraoperative normovolemic hemodilution and the preoperative use of EPO (Erytropoetin) should be considered. In a retrospective study, we analyzed 438 patients who underwent orthognathic surgery. The perioperative blood loss was determined in order to calculate the transfusion probability in case of the acceptance of 7.5 g/dl hemoglobin as the critical value in patients without cardiac failures. Only four patients undergoing Le Fort I osteotomy (1.55%) or bimaxillary osteotomy (3.03%) had to be transfused. Therefore, the statistical transfusion need was clearly below 10%. Due to this, there was no general need for autologous blood donation. However, in individual cases with low hemoglobin and/or low blood volume, a transfusion need can be predicted. In those few cases, autologous blood donation may be indicated. However, in case of a more conservative indication to transfusion (hemoglobin 10 g/dl), more than 10% of the patients with bimaxillary osteotomies would have been transfused. Autologous blood donation is then indicated according to the German regulations for transfusion. If low hemoglobin values are accepted, the exact individual blood demand should be calculated, a blood saving operation technique should be used, adequate postoperative warding is necessary, and compatible allogenic red cell concentrates should be quickly available.