Factors associated with failed post-operative voiding trial after urogynecologic surgery

Objectives: Post-operative urinary retention requiring discharge with an indwelling catheter has a significant impact on patient satisfaction. We aimed to identify factors associated with failed post-operative voiding trial (VT) in patients undergoing prolapse repair and/or urinary incontinence procedures.

Methods: This was a retrospective cohort study performed at a large academic center and a large county hospital from January 2019 to January 2022. Included patients underwent planned pelvic organ prolapse surgery or urinary incontinence surgery and subsequent VT via retrograde fill prior to discharge home. Patients who failed their VT were discharged with an indwelling catheter. Cases with intra-operative complications, planned catheterization, or those in which no VT was performed were excluded. Demographic, intra-, and post-operative data were abstracted from the medical record. Post-operative VT failure was defined as failure to void 2/3 or greater of instilled volume on retrograde fill, with subsequent discharge with catheter in place. Multivariable logistic regression was used to determine odds ratios and 95% confidence intervals (CI) with statistical significance indicated by p < 0.05.

Results: A total of 465 patients were included in the analysis (Table 1). The overall rate of failed VT was 23%. The only factor independently associated with failed post-operative VT was BMI. Patients with higher BMI were less likely to fail VT (OR 0.93, CI 0.89-0.98). Failure of VT was not associated with age, parity, diabetes, prior surgeries, pre-op urinary incontinence type (stress, urge, mixed), surgery type, EBL, VT fill volume or date of post-operative VT (Table 2). Specifically, failure rate remained similar for those with VT on POD#2 or greater compared with those on POD#0 (OR 0.9, CI 0.24-3.05). Additionally, increased bladder filling more than the standard 300 cc did not increase pass rates (OR 1.26, CI 0.74-2.15). While surgery type overall was not associated with VT failure, isolated mid-urethral sling placement had a reduced odds of failing VT compared to pelvic organ prolapse repair (OR 0.38, 0.16-0.86). Overall, the incidence of post-operative urinary tract infection requiring treatment (2%) was too low to determine a difference between those who failed and passed post-operative VT.

Conclusions: In this cohort, we found that patients with a higher BMI were more likely to pass their post-operative VT. Intra-operative factors or surgery type were less likely to contribute to failed VT. Interestingly, there was no increase in pass rate for those with VT based on post-operative day or fill volume, and there was overall a low rate of urinary tract infection. Thus, timing of VT should be based on patient specific factors and preferences. Studies to examine how BMI contributes to post-operative urinary retention are needed to confirm our findings and determine possible mechanisms to better inform patient counseling.