title: Urinary fistula after robot-assisted partial nephrectomy: a multicentre analysis of 1 791 patients.
abstract: OBJECTIVE
  To evaluate the incidence of and risk factors for a urine leak in a large multicentre, prospective database of robot-assisted partial nephrectomy (RPN).
  
  
  METHODS
  A database of 1 791 RPN from five USA centres was reviewed for urine leak as a complication of RPN. Patient and tumour characteristics were compared between patients with and those without postoperative urine leaks. Fisher's exact test was used for qualitative variables and Wilcoxon sum-rank tests were used for quantitative variables. A review of the literature on PN and urine leak was conducted.
  
  
  RESULTS
  Urine leak was noted in 14/1 791 (0.78%) patients who underwent RPN. The mean (sd) nephrometry score of the entire cohort was 7.2 (1.9), and 8.0 (1.9) in patients who developed urine leak. The median (range) postoperative day of presentation was 13 (3-32) days. Patients with urine leak presented in delayed fashion with fever (two of the 14 patients, 14%), gastrointestinal complaints (four patients, 29%), and pain (five patients, 36%). Eight of the 14 patients (57%) required admission, while eight (57%) and nine (64%) had a drain or stent placed, respectively. Drains and stents were removed after a median (range) of 8 (4-13) days and 21 (8-83) days, respectively. Variables associated with urine leak included tumour size (P = 0.021), hilar location (P = 0.025), operative time (P = 0.006), warm ischaemia time (P = 0.005), and pelvicalyceal repair (P = 0.018). Upon literature review, the historical incidence of urine leak ranged from 1.0% to 17.4% for open PN and 1.6-16.5% for laparoscopic PN.
  
  
  CONCLUSIONS
  The incidence of urine leak after RPN is very low and may be predicted by some preoperative factors, affording better patient counselling of risks. The low urinary leak rate may be attributed to the enhanced visualisation and suturing technique that accompanies the robotic approach.
authors.affiliation: Division of Urology, Washington University School of Medicine, St. Louis, MO, USA.
authors.forename: Aaron M
authors.initials: AM
authors.lastname: Potretzke
authors.affiliation: Division of Urology, Washington University School of Medicine, St. Louis, MO, USA.
authors.forename: Brent Alexander
authors.initials: BA
authors.lastname: Knight
authors.affiliation: Cleveland Clinic, Glickman Urological and Kidney Institute, Cleveland, OH, USA.
authors.forename: Homayoun
authors.identifier: http://orcid.org/0000-0001-8424-1087
authors.initials: H
authors.lastname: Zargar
authors.affiliation: Cleveland Clinic, Glickman Urological and Kidney Institute, Cleveland, OH, USA.
authors.forename: Jihad H
authors.initials: JH
authors.lastname: Kaouk
authors.affiliation: Henry Ford Hospital, Vattikuti Urology Institute, Detroit, MI, USA.
authors.forename: Ravi
authors.initials: R
authors.lastname: Barod
authors.affiliation: Henry Ford Hospital, Vattikuti Urology Institute, Detroit, MI, USA.
authors.forename: Craig G
authors.initials: CG
authors.lastname: Rogers
authors.affiliation: Urology, NYU Medical Center, New York, NY, USA.
authors.forename: Alon
authors.initials: A
authors.lastname: Mass
authors.affiliation: Urology, NYU Medical Center, New York, NY, USA.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Stifelman
authors.affiliation: Johns Hopkins Medical Institutions, Baltimore, MD, USA.
authors.forename: Michael H
authors.initials: MH
authors.lastname: Johnson
authors.affiliation: Johns Hopkins Medical Institutions, Baltimore, MD, USA.
authors.forename: Mohamad E
authors.initials: ME
authors.lastname: Allaf
authors.affiliation: Division of Urology, Washington University School of Medicine, St. Louis, MO, USA.
authors.forename: Robert
authors.initials: R
authors.lastname: Sherburne Figenshau
authors.affiliation: Division of Urology, Washington University School of Medicine, St. Louis, MO, USA.
authors.forename: Sam B
authors.initials: SB
authors.lastname: Bhayani
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009392:Nephrectomy / Q000009:adverse effects*; D011183:Postoperative Complications / Q000453:epidemiology / Q000628:therapy; D012189:Retrospective Studies; D065287:Robotic Surgical Procedures / Q000009:adverse effects*; D015607:Stents; D014548:Urinary Fistula / Q000453:epidemiology / Q000209:etiology / Q000628:therapy
keywords: partial nephrectomy; robot-assisted partial nephrectomy; urine fistula; urine leak