title: Off-Clamp versus On-Clamp Robotic Partial Nephrectomy: A Multicenter Match-Paired Case-Control Study.
abstract: BACKGROUND
  The aim of this study was to compare the outcomes of on-clamp and off-clamp robotic partial nephrectomy (RPN).
  
  
  METHODS
  The charts of all patients who underwent an RPN at 8 institutions between 2010 and 2014 were retrospectively reviewed. The patients who underwent an off-clamp RPN were matched to on-clamp RPN in a 1-4 fashion according to the following variables: RENAL score, tumor size and surgeon's experience. Pre-, intra-, and postoperative data were compared between both groups.
  
  
  RESULTS
  Among 525 RPN, 26 were performed off-clamp (5%). They were matched to 104 on-clamp RPN. The complications rate (15.5 vs. 7.7%, p = 0.53), major complications rate (4.9 vs. 3.9%; p = 0.82), and transfusions rate (0 vs. 4.9%; p = 0.58) did not differ significantly between the clamped and unclamped groups. Conversely, estimated blood loss was higher in the off-clamp group (266.4 vs. 284.6 mL, p = 0.048) and so was the rate of conversion to radical nephrectomy (0 vs. 7.7%, p = 0.04). Postoperative preservation of renal function was comparable in both groups.
  
  
  CONCLUSIONS
  Off-clamp RPN is feasible for a small subgroup of renal tumors without increased risk of postoperative complications but at the cost of higher estimated blood loss and increased risk of conversion to radical nephrectomy.
authors.affiliation: Service d'Urologie, CHU Rennes, Rennes, France.
authors.forename: Benoit
authors.initials: B
authors.lastname: Peyronnet
authors.forename: Zine-Eddine
authors.initials: ZE
authors.lastname: Khene
authors.forename: Benjamin
authors.initials: B
authors.lastname: Pradère
authors.forename: Thomas
authors.initials: T
authors.lastname: Seisen
authors.forename: Grégory
authors.initials: G
authors.lastname: Verhoest
authors.forename: Alexandra
authors.initials: A
authors.lastname: Masson-Lecomte
authors.forename: Yohann
authors.initials: Y
authors.lastname: Grassano
authors.forename: Mathieu
authors.initials: M
authors.lastname: Roumiguié
authors.forename: Jean-Baptiste
authors.initials: JB
authors.lastname: Beauval
authors.forename: Hervé
authors.initials: H
authors.lastname: Baumert
authors.forename: Stéphane
authors.initials: S
authors.lastname: Droupy
authors.forename: Nicolas
authors.initials: N
authors.lastname: Doumerc
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Bernhard
authors.forename: Christophe
authors.initials: C
authors.lastname: Vaessen
authors.forename: Franck
authors.initials: F
authors.lastname: Bruyère
authors.forename: Alexandre
authors.initials: A
authors.lastname: de la Taille
authors.forename: Morgan
authors.initials: M
authors.lastname: Rouprêt
authors.forename: Karim
authors.initials: K
authors.lastname: Bensalah
mesh_terms: D002983:Clinical Competence; D003250:Constriction; D005602:France; D006801:Humans; D007680:Kidney Neoplasms / Q000473:pathology / Q000601:surgery*; D009392:Nephrectomy / Q000009:adverse effects / Q000379:methods*; D011183:Postoperative Complications / Q000209:etiology / Q000628:therapy; D012189:Retrospective Studies; D012307:Risk Factors; D065287:Robotic Surgical Procedures / Q000009:adverse effects / Q000379:methods*; D013997:Time Factors; D016896:Treatment Outcome; D047368:Tumor Burden; D052096:Warm Ischemia / Q000009:adverse effects / Q000379:methods*
keywords: Blood loss; Kidney neoplasms; Laparoscopy; Partial nephrectomy; Surgical technique