title: Blood loss during posterior spinal fusion for adolescent idiopathic scoliosis.
abstract: METHODS
  Retrospective uncontrolled case series.
  
  
  OBJECTIVE
  The purpose of this study was to determine the association, if any, between intraoperative blood loss and need for transfusion with the use of periapical (Ponte) osteotomies, as well as other patient and surgical variables among patients with adolescent idiopathic scoliosis (AIS) undergoing posterior spinal instrumentation and fusion.
  
  
  BACKGROUND
  Blood loss during posterior spinal fusion for AIS can be substantial. Numerous techniques are used to minimize intraoperative blood loss and the need for allogeneic transfusion. However, it is unclear which patient and surgeon variables affect blood loss most significantly.
  
  
  METHODS
  A review was conducted on consecutive patients with AIS who had undergone posterior spinal fusion from July 1997 to February 2013 by a single primary surgeon at 1 institution. The relationship of estimated blood loss, normalized blood loss (normalized blood loss = estimated blood loss/number of levels fused/patient's weight in kilograms), autologous blood retrieved, and allogeneic transfusion received with various patient- and procedure-related variables were analyzed.
  
  
  RESULTS
  Estimated blood loss, normalized blood loss, and autologous blood retrieved were higher in patients who underwent periapical Ponte osteotomies (n = 38) (P < 0.0001, P < 0.001, P < 0.01, respectively). The mean major curve correction was 64% in patients without osteotomies, and 65% in patients with osteotomies (P = 0.81). All patients who underwent osteotomies (38/38) received allogeneic transfusion versus 26% (19/73) of those without osteotomies (P < 0.001). The likelihood of transfusion correlated with increasing number of osteotomies and a lower preoperative hemoglobin level (odds ratio, 3.34; P = 0.003; and odds ratio, 0.51; P = 0.02, respectively).
  
  
  CONCLUSIONS
  In patients with AIS undergoing posterior spinal fusion with instrumentation, performing periapical osteotomies increased all measures of intraoperative blood loss and need for transfusion without substantially improving major curve correction. As expected, a lower preoperative hemoglobin level was observed in patients who received a blood transfusion after posterior instrumentation and fusion.
  
  
  METHODS
  4.
authors.affiliation: *Thomas Jefferson University/Rothman Institute, Philadelphia, PA †Rutgers University-New Jersey Medical School, Newark, NJ; and ‡Medstar Georgetown University Hospital, Washington, DC.
authors.forename: John D
authors.initials: JD
authors.lastname: Koerner
authors.forename: Anuradha
authors.initials: A
authors.lastname: Patel
authors.forename: Caixia
authors.initials: C
authors.lastname: Zhao
authors.forename: Catherine
authors.initials: C
authors.lastname: Schoenberg
authors.forename: Avantika
authors.initials: A
authors.lastname: Mishra
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Vives
authors.forename: Sanjeev
authors.initials: S
authors.lastname: Sabharwal
mesh_terms: D000293:Adolescent; D016063:Blood Loss, Surgical / Q000706:statistics & numerical data*; D001803:Blood Transfusion / Q000379:methods / Q000706:statistics & numerical data*; D001863:Bone Screws; D005260:Female; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D008297:Male; D015999:Multivariate Analysis; D057234:Preoperative Period; D012044:Regression Analysis; D012189:Retrospective Studies; D012600:Scoliosis / Q000601:surgery*; D013123:Spinal Fusion / Q000295:instrumentation / Q000379:methods*; D014184:Transplantation, Homologous; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D006454:Hemoglobins