Factors for intraoperative blood loss in bimaxillary osteotomies.

[PURPOSE] Autologous blood donation is not routinely recommended for all cases of orthognathic surgery. The aim of this study was to evaluate the factors for blood loss during bimaxillary osteotomies that might indicate preoperative blood donation.

[PATIENTS AND METHODS] In a prospective study, 127 consecutive patients undergoing bimaxillary surgery within a 14-month period were examined for hemoglobin and hematocrit reduction. Possible factors for intraoperative blood loss such as operating time, application of hydroxyethyl starch in segmental osteotomies, experience of the surgeon, and additional procedures (genioplasty, malar osteotomy, iliac crest graft) were statistically analyzed.

[RESULTS] The experience of the surgeon had no influence on the blood loss. Operating time and Quick value correlated significantly with hemoglobin and hematocrit drop after surgery. There was no difference between 1-piece maxilla cases with or without additional procedures and segmental maxilla cases without additional procedures. Only for the group of patients with segmental osteotomies and additional procedures was a significant higher blood loss found. Two patients (1.6%) received 1 unit of blood.

[CONCLUSION] For patients undergoing bimaxillary osteotomies with segmentation of the maxilla and additional procedures, a preoperative donation of autologous blood should be considered.