Background: The purpose of this study was to determine the consumption of blood products duringorthognathic surgeries by age, sex, blood group, operation time, and the amount of blood loss.Methods: This is a retrospective cohort study. Patients who underwent bimaxillary osteotomy were studied.The study focused on types and amount of blood loss, blood products used, and change in patient’s hemoglobin(Hb) and hematocrit (HCT). Patients’ demographic data, blood type, and duration of surgery were variables ofthe research.Results: A total of 133 patients (52 males and 81 females) with a mean age of 22.950 ± 4.241 years formed thestudy population. Average blood loss was 556.32 ± 245.05 ml and the average operating time was259.96 ± 51.56 minutes. Results demonstrated that duration of the surgical and blood loss in males was higherthan females. The mean of Hb and HCT levels before surgeries was 13.56 ± 1.30 and 40.47 ± 4.30,respectively, which significantly (P < 0.001) decreased to 11.969 ± 1.200 and 35.782 ± 3.800 1 day after theoperations. The transfused blood products consisted of packed cells (5.4%), fresh frozen plasma (37.3%), andhydroxyethyl starch (57.3%). The percentage of patients who did not receive any transfusion was generallyhigher in the positive blood types than negative ones, with the highest percentage being in the AB+ group.Conclusions: A risk of using blood products particularly packed cells may increase if blood loss was above of800 ml and surgical duration more than 300 minutes. The duration of orthognathic surgery may have asignificant effect on blood loss and blood transfusions. It seems subjects with positive blood types may have alower risk for transfusion.© 2014 Tehran University of Medical Sciences. All rights reserved.Citation: Eftekharian H, Dadain S, Aliabadi E, Tabrizi R. Blood Products Use in Bimaxillary OrthognathicSurgeries: A Retrospective Study. Acad J Surg, 2016; 3(1-2): 2-6 .