Risk factors for trocar injury to the bladder during mid urethral sling procedures.

Purpose: We determined the incidence of and risk factors for bladder injury during mid urethral sling procedures for stress urinary incontinence.

Materials And Methods: At our institution 1,136 consecutive women underwent a mid urethral sling procedure (retropubic in 874 and transobturator in 262) and routine intraoperative cystoscopy between 1999 and 2007, and were followed to determine the clinical outcome. Statistical analysis was performed using the chi-square and independent t tests, and ANOVA to compare patients with and without bladder perforation by baseline characteristics and major risk factors. A total of 45 variables were included in analysis. Multivariate analysis to predict events was done with logistic regression models with stepwise forward selection.

Results: Bladder injury was noted in 34 patients (3%) and all except 1 were during a retropubic sling procedure (p <0.0001). Of the perforations 32 (94%) were associated with an inexperienced surgeon (p <0.0001). Multivariate analysis revealed that rectocele (OR 6.2), local anesthesia (OR 5.9), body mass index less than 30 kg/m(2) (OR 5.6), previous Cesarean section (OR 3.7) and previous colposuspension (OR 3.2) were significant independent risk factors for perforation. Urethral injury was detected intraoperatively in 2 women (0.2%) with a retropubic sling.

Conclusions: Our results indicate that previous Cesarean section, colposuspension, body mass index less than 30 kg/m(2), rectocele and local anesthesia are independent risk factors for bladder perforation during mid urethral sling procedures. This occurs mainly during a retropubic sling procedure and when the surgeon is inexperienced.