Mid-urethral sling (MUS) placement in female patients with stress urinary incontinence can lead to complications such as obstructive symptoms (OS). This study aims to validate a previously developed nomogram estimating the probability of bladder outlet obstruction (BOO) in symptomatic women following MUS.
Following IRB approval, presurgical urodynamic study (UDS) data from 107 women who underwent MUS excision for OS were retrospectively reviewed. Patients with neurogenic bladder or pelvic organ prolapse on physical examination were excluded. Demographic data, urogynecology history, OS, pelvic surgeries, MUS operative notes, urinary tract infections (UTI), UDI-6 questionnaire scores, and urodynamic (UDS) parameters (Qmax, PdetQmax, volume voided, post void residual) were collected from the EMR. UDS were conducted according to ICS guidelines. Patients’ presurgical odds of BOO were determined using a previously developed nomogram scoring pressure-flow values, BMI, and age (with dominant variables of Qmax and PdetQmax).
From 2006-2013, 81 patients met study criteria. Mean age at time of sling excision was 61 11 years, and mean time from MUS placement to excision was 3 3 years. Sling types were transvaginal tape (n=35), transobturator tape (n=20), and undocumented by surgical note (n=26). Common OS included incomplete voiding (n=37), weak stream (n=24), straining (n=24), hesitancy (n=13), and prior retention (n=13). Recurrent UTI was documented in 34.5% (n=28). On UDI-6, mean score was 2.5 out of 3 for Question 1, 2.3 for Q2, and 1.4 for Q5. Using nomogram parameters, 37 women (46%) had a >95% estimated probability of BOO, 8 had an estimate of 91–94%, and 16 had an estimate of 76–90%, indicating high likelihood of obstruction. 12 women had equivocal prediction (25–75%), and 8 (0-25%) had low probability of BOO (seeFigure 1).
This study provides preliminary validation of a proposed nomogram for estimating BOO in symptomatic women following MUS. The prediction of BOO can be aided by this nomogram but should also take into consideration all post-MUS presenting symptoms.
None
