Oral Presentation 3: Risk Factors Leading To Post Sling Voiding Dysfunction And Sling Revision-a Multicenter Case-Control Study

OBJECTIVES: The purpose of this study was to determine risk factors for voiding dysfunction necessitating sling revision after midurethral polypropylene sling placement. MATERIALS AND METHODS: This multicenter case-control study included patients who underwent midurethral polypropylene sling placement and subsequent sling revision secondary to voiding dysfunction from January 1999 to January 2007 from nine urogynecologic centers across the US. Controls were patients who had undergone midurethral polypropylene sling placement not necessitating revision and were matched by patient age and date of surgery. Data collected included demographics, urodynamic study data, sling type, operative data, and clinical information before and after sling revision. Univariate analyses identified risk factors for voiding dysfunction, based on chi square tests for categorical variables, independent samples t-tests for normally distributed continuous variables, and Mann-Whitney rank sums tests for non-normally distributed continuous variables. Direct logistic regression analysis was used to determine which diagnostic variables predicted voiding dysfunction necessitating sling revision. RESULTS: One hundred ninety seven patients met case study criteria with 2 controls matched to each case for a total of 394 controls. Two hundred fourteen patients had all data points and were included in the logistic regression analysis. No specific patient characteristics increased the risk for sling revision including: age, race, BMI, smoking status, menopause status, hormone use, COPD/asthma history, previous incontinence or prolapse surgery, prior hysterectomy, preoperative diagnosis, and presence of intrinsic sphincter deficiency. Risk factors for sling revision did include: retropubic sling type (OR = 2.11, 95% CI 1.03–4.34, P = .04) and concurrent surgery (OR = 4.21, 95% CI 1.96–9.04, P = .0002) In contrast, pre-sling post void residual values, maximum detrusor pressures, maximum urinary flow rates, general anesthesia, and sling tensioning with cough/crede versus visual placement did not significantly predict the need for sling revision (all P-values >.05). CONCLUSION: This study determined that the retropubic sling type and concurrent surgery at the time of sling placement are risk factors for postoperative voiding dysfunction and sling revision. Urodynamic findings, baseline demographic information, anesthesia type and sling tensioning technique were not found to be predictive of voiding dysfunction and need for sling revision.