title: Blood loss in orthognathic surgery: a systematic review.
abstract: OBJECTIVE
  Intraoperative blood loss during orthognathic surgery is frequently abundant and sometimes requires blood transfusion. The aim of the present study was to conduct a systematic review of the published data regarding intraoperative blood loss during orthognathic surgical interventions, including Le Fort I osteotomy, mandibular ramus osteotomy, and both combined, to determine the range of information available to help surgeons better prepare themselves, their patients, and the auxiliary support needed for this type of surgery and the transfusion requirements.
  
  
  METHODS
  Selected reports from the PubMed and Cochrane Library databases for studies conducted from 1978 to 2008 were evaluated to determine whether they included information on the volume of bleeding during surgery and the factors that might have influenced the amount of bleeding. Of the 90 reports examined and evaluated, 7 were included in the critical analysis conducted as a part of the present systematic review.
  
  
  RESULTS
  Referring to the reports used for statistical analysis of the volume of blood loss, the mean intraoperative bleeding volume was 436.11 mL, the mean of the standard deviations was ±207.89 mL, and mean surgery duration was 196.9 minutes.
  
  
  CONCLUSIONS
  Our results have shown that the intraoperative bleeding observed in patients during Le Fort I or mandibular ramus osteotomies or both combined was less than the limits set for blood transfusion. However, bleeding was occasionally heavier, and surgeons should be prepared for heavier bleeding by reserving blood at a blood bank or by preparing an autotransfusion.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Faculty of Medicine and Dentistry, University of Santiago de Compostela, Spain.
authors.forename: Alejandra
authors.initials: A
authors.lastname: Piñeiro-Aguilar
authors.forename: Manuel
authors.initials: M
authors.lastname: Somoza-Martín
authors.forename: José M
authors.initials: JM
authors.lastname: Gandara-Rey
authors.forename: Abel
authors.initials: A
authors.lastname: García-García
mesh_terms: D016063:Blood Loss, Surgical / Q000706:statistics & numerical data*; D006801:Humans; D008334:Mandible / Q000601:surgery; D008437:Maxilla / Q000601:surgery; D056948:Orthognathic Surgical Procedures / Q000009:adverse effects*; D019340:Osteotomy, Le Fort / Q000009:adverse effects; D013997:Time Factors