title: Operative duration as an independent risk factor for postoperative complications in single-level lumbar fusion: an analysis of 4588 surgical cases.
abstract: METHODS
  Multicenter retrospective cohort study.
  
  
  OBJECTIVE
  To estimate the impact of increasing surgical duration on outcomes after single-level lumbar fusion.
  
  
  BACKGROUND
  Lumbar fusion is a widely used practice for the treatment of disability and chronic low back pain. Longer operative duration is shown to correlate with increased morbidity and mortality in various surgical disciplines, but no large-scale study has been performed to validate this relationship in lumbar spine surgery.
  
  
  METHODS
  The American College of Surgeons National Surgical Quality Improvement Program was retrospectively reviewed to identify all patients who underwent lumbar fusion procedures during 2006 to 2011. Thirty-day morbidity and mortality rates were reported on the basis of operative time, whereas multivariate logistic regression model was used to examine operative duration as an independent risk factor for outcomes.
  
  
  RESULTS
  A total of 4588 patients were included in the analysis. The mean operative duration for all patients was 197 ± 105 minutes. Our multivariate risk-adjusted regression models demonstrated that increasing operative time was associated with step-wise increase in risk for overall complications (odds ratio [OR], 2.09-5.73), medical complications (OR, 2.18-6.21), surgical complications (OR, 1.65-2.90), superficial surgical site infection (OR, 2.65-3.97), and postoperative transfusions (OR, 3.25-12.19). Operative duration of 5 hours or more was also associated with increased risk of reoperation (OR, 2.17), organ/space surgical site infection (OR, 9.72), sepsis/septic shock (OR, 4.41), wound dehiscence (OR, 10.98), and deep vein thrombosis (OR, 17.22).
  
  
  CONCLUSIONS
  Our data suggest that increasing operative duration is associated with a wide array of complications. Operative duration is, therefore, an important quality metric in the performance of lumbar fusion. Strategies to reduce operative time and further research to identify risk factors that are associated with longer surgical duration are needed for improved patient outcomes.
  
  
  METHODS
  3.
authors.affiliation: *Rosalind Franklin University of Medicine and Science, Chicago Medical School, North Chicago, IL Departments of †Orthopaedic Surgery, ‡Anesthesiology, and §Surgery, Northwestern University, Feinberg School of Medicine, Chicago, IL.
authors.forename: Bobby D
authors.initials: BD
authors.lastname: Kim
authors.forename: Wellington K
authors.initials: WK
authors.lastname: Hsu
authors.forename: Gildasio S
authors.initials: GS
authors.lastname: De Oliveira
authors.forename: Sujata
authors.initials: S
authors.lastname: Saha
authors.forename: John Y S
authors.initials: JY
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D016009:Chi-Square Distribution; D005260:Female; D006801:Humans; D016015:Logistic Models; D008159:Lumbar Vertebrae / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D061646:Operative Time; D011183:Postoperative Complications / Q000175:diagnosis / Q000209:etiology* / Q000601:surgery; D012086:Reoperation; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013123:Spinal Fusion / Q000009:adverse effects*; D013997:Time Factors; D016896:Treatment Outcome; D014481:United States