title: Identification and validation of risk factors for vesicourethral leaks following radical retropubic prostatectomy.
abstract: OBJECTIVE
  To identify risk factors for anastomotic leaks at cystography following radical retropubic prostatectomy (RRP).
  
  
  METHODS
  In phase 1 the records of a 107 RRP patients were reviewed. Data collected included comorbidity, pathological factors and intra- and postoperative complications. From these, risk factors were identified that were associated with a leak at cystography. In phase 2 (n = 46) we prospectively tested if the risk factors identified could predict an anastomotic leak.
  
  
  RESULTS
  In phase 1 the only identifiable risk factors were that of a difficult anastamosis, an unsatisfactory intraoperative test flush and the presence of a urinary tract infection. One or more of these events were found in 17/25 (68%) of the patients who leaked (P < 0.0001). Of the eight leaks missed, five were classed as minimal and did not require repeat cystography. Within the prospective phase 2 cohort one or more risk factors were present in 7/10 (70%) of the patients who leaked. In contrast, the identified risk factors were present in only 5/36 (13.8%) of the patients who did not leak (P < 0.001). The specificity of the test was 86.1% with a sensitivity of 70%. This gave a positive predictive value of 58.3% and a negative predictive value of 91.1%. Three leaks (two minimal and one moderate) would have been missed but 31 (67.3%) patients would have avoided an unnecessary radiological study.
  
  
  CONCLUSIONS
  Using a retrospective and prospective cohort of patients we have shown that a cystogram following RRP can be safely avoided in the absence of the identified risk factors.
authors.affiliation: Department of Urology and Radiology, James Cook University Hospital, Middlesbrough, UK. v.j.gnanapragasam@ncl.ac.uk
authors.forename: Vincent J
authors.initials: VJ
authors.lastname: Gnanapragasam
authors.forename: Paul
authors.initials: P
authors.lastname: Baker
authors.forename: Geoffrey P
authors.initials: GP
authors.lastname: Naisby
authors.forename: David
authors.initials: D
authors.lastname: Chadwick
mesh_terms: D000714:Anastomosis, Surgical / Q000009:adverse effects; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011468:Prostatectomy; D011859:Radiography; D012189:Retrospective Studies; D012307:Risk Factors; D012680:Sensitivity and Specificity; D014521:Urethra / Q000601:surgery*; D001743:Urinary Bladder / Q000000981:diagnostic imaging* / Q000601:surgery*; D014552:Urinary Tract Infections / Q000150:complications