title: Analysis of impact of body mass index on outcomes of laparoscopic renal surgery.
abstract: OBJECTIVE
  As the prevalence of obesity increases in the United States, it has become more important to assess its impact on surgical outcomes. We evaluated the significance of obesity on laparoscopic radical nephrectomy (LRN) and laparoscopic partial nephrectomy (LPN).
  
  
  METHODS
  This was a prospective database study evaluating patients who underwent either LRN or LPN from October 2002 to January 2006. Patients were divided into five groups as determined by the World Health Organization body mass index (BMI) classification: less than 25.0, 25.0 to 29.9, 30.0 to 34.9, 35.0 to 39.9, and 40.0 kg/m2 or more. Demographic (age, tumor size, American Society for Anesthesiologists score), operative (estimated blood loss, operative time, open conversion), and postoperative (complications, hospital stay, margin status) data were compared.
  
  
  RESULTS
  Of 239 patients who had undergone LRN or LPN during the study period, 146 underwent LRN and 85 underwent LPN. Of the 239 patients, 42% were obese. No statistical significance was determined for estimated blood loss, operative time, hospital stay, number of open conversions, or complications. However, a trend toward increased operative time and intraoperative complications was determined using linear and logistic regression analyses.
  
  
  CONCLUSIONS
  Laparoscopic renal surgery is safe in overweight and obese patients and may be the surgical management of choice in this subset of patients. However, obese patients should be warned that their degree of obesity may be associated with increased difficulty of surgery as reflected by a trend toward longer operative times and more intraoperative complications.
authors.affiliation: Department of Surgery, Section of Urology, University of Chicago Pritzker School of Medicine, Chicago, Illinois 60637, USA. emgong@post.harvard.edu
authors.forename: Edward M
authors.initials: EM
authors.lastname: Gong
authors.forename: Marcelo A
authors.initials: MA
authors.lastname: Orvieto
authors.forename: Mark B
authors.initials: MB
authors.lastname: Lyon
authors.forename: Alvaro
authors.initials: A
authors.lastname: Lucioni
authors.forename: Glenn S
authors.initials: GS
authors.lastname: Gerber
authors.forename: Arieh L
authors.initials: AL
authors.lastname: Shalhav
mesh_terms: D015992:Body Mass Index; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000150:complications* / Q000601:surgery*; D010535:Laparoscopy; D008297:Male; D008875:Middle Aged; D009392:Nephrectomy / Q000379:methods*; D009765:Obesity / Q000150:complications*; D011446:Prospective Studies; D012307:Risk Factors; D016896:Treatment Outcome