Factors that determine intraoperative blood loss in bimaxillary osteotomies and the need for preoperative blood preparation

Abstract

Purpose: To define factors that influence blood loss in bimaxillary osteotomies and the need for blood preparation at the Faculty of Dentistry, Mahidol University, Bangkok, Thailand. Patients and Methods: We retrospectively studied 208 patients who underwent bimaxillary osteotomies during 2005 to 2009. Possible factors for intraoperative blood loss such as age, body weight, gender, operative time, experience of the surgeons, and different operative procedures were statistically analyzed. Results: Female patients had a significantly higher percentage of blood loss from allowable blood loss than male patients (P =.006). Experience of the surgeons had a significant influence on blood loss (P =.02) and operative time (P < .001). No significant difference in blood loss was found among the 4 groups classified by operation (P =.852). Simple regression analysis showed a significantly positive correlation between blood loss and duration of operation (R 2 = 0.15, P < .001). There was no correlation between blood loss and patient age (P =.35). Conclusion: The factors that influence blood loss include patient gender, experience of the surgeon, and operative time. Blood preparation should be considered in women, especially small individuals in whom a long operative time is expected and who are being operated on by an inexperienced surgeon. Because of the low rate of transfusion, a group-and-save policy is appropriate. © 2011 American Association of Oral and Maxillofacial Surgeons.