Risk Factors for Bladder Perforation at the Time of Retropubic Midurethral Sling Placement

IMPORTANCE: There is conflicting evidence regarding predictive factors for bladder perforation during retropubic midurethral sling (R-MUS) placement and lack of evidence to support adoption of techniques to minimize such injury. OBJECTIVES: The aims of the study were to describe the incidence of and factors associated with bladder perforation during R-MUS placement and to explore whether retropubic hydrodissection decreases the likelihood of perforation. STUDY DESIGN: This is a case-control study of women undergoing R-MUS placement from 2007 to 2017. Cases were identified by review of the operative reports for evidence of bladder perforation. Patients without bladder perforation were defined as controls and were matched to cases in a 3:1 ratio by surgeon, sling type, and surgery date. RESULTS: A total of 1,187 patients underwent R-MUS placement. The incidence of bladder perforation was 8% (n = 92 patients); 276 controls were matched accordingly (N = 368). Patients with bladder perforations were more likely to have a body mass index (BMI) less than 30 (P = 0.004) and to have a diagnosis of endometriosis (P = 0.02). They were also more likely to have had previous hysterectomy (P = 0.03) and urethral bulking (P = 0.01). On logistic regression, bladder perforation remained associated with a BMI less than 30 (adjusted odds ratio, 2.22 [95% confidence interval, 1.30-3.80]) and endometriosis (adjusted odds ratio 2.90 [95% confidence interval, 1.15-7.01]). Retropubic hydrodissection was performed in 62% of the patients and was not associated with a lower risk of perforation (P = 0.86). CONCLUSIONS: The incidence of bladder perforation was 8%. The risk of this complication is higher in patients with a BMI less than 30 and/or endometriosis. Retropubic hydrodissection may not decrease the likelihood of this event.