Variables predictive of voiding disfunction following aponeurotic sling surgery: multivariate analysis.

INTRODUCTION: Aponeurotic sling surgeries can evolve with obstruction or voiding dysfunction in 5 to 20% of patients. There are few studies on factors that could possibly predispose to voiding difficulties or urinary retention. The objective of this work is to identify these potential clinical or urodynamic factors.

MATERIALS AND METHODS: Records from 130 patients who underwent aponeurotic sling surgeries were reviewed. All patients underwent a throughout urodynamic study during pre-operative investigation. The variables studied were age above 65 years, previous pelvic surgeries, concomitant surgeries, post-voiding residue higher than 100 mL, vesical obstruction (according to Blaivas-Groutz nomogram) and urinary flow under 12 mL/s. Post-voiding residue was assessed on the seventh post-operative day through vesical catheterization. Recovering of spontaneous voiding after 7 post-operative days or with a residue higher than 100 mL, was regarded as voiding dysfunction. Univariate analysis was performed with qui-square test and Fisher's exact test, and multivariate analysis was performed by logistic regression with alpha = 5%.

RESULTS: Age in the studied group ranged from 41 to 83 years (mean 56.7 years), with 69 (53%) patients having urethral hypermobility and 61 (47%) having intrinsic urethral lesion. Normal voiding occurred in 97 (75.6%) women with 7 post-operative days. The only significant variable in the univariate (p = 0.014) and multivariate (p = 0.017) analysis was post-voiding residue higher than 100 mL.

CONCLUSION: Pre-operative presence of a post-voiding residual urine higher than 100 mL was the only variable predictive of voiding dysfunction.