Early urodynamic findings after complete primary repair of exstrophy.

ABSTRACT

INTRODUCTION: Detrusor contraction in bladder exstrophy (BE) patients following reconstruction is poorly understood as there are few published studies assessing urodynamic findings in this population. Understanding the ability of the detrusor to contract in BE patients early after closure may be able to inform the longer-term management and potential for the development of future continence in this population. OBJECTIVE: We sought to evaluate early detrusor contraction using urodynamic studies (UDS) in children who had previously undergone complete primary repair of bladder exstrophy (CPRE). We hypothesized that a majority of children with BE would display the presence of normal detrusor contractile function after CPRE. STUDY DESIGN: A retrospective review of our prospectively collected database was performed for all patients with a diagnosis of classic BE who underwent primary CPRE between 2013 and 2017. From this cohort we identified patients with at least one post-operative UDS at 3 years of age or older who had undergone an initial CPRE. Our primary outcome was the presence of a detrusor contraction demonstrated on UDS. RESULTS: There were 50 children (31 male, 19 female) with CBE who underwent CPRE between 2013 and 2017.There were 26 (13 male, 13 female) who met inclusion criteria. Median age was 3.5 (IQR 3.2-4.7) years at the time of UDS Sixteen of the 26 (61.5%) generated a sustained detrusor contraction generating a void, with a median peak voiding pressure of 38 cm H20 (IQR 28-51). The median bladder capacity reached was 48 ml, which represented a median of 30% of expected bladder capacity. The median post void residual (PVR) for the entire cohort was 26 ml (IQR 9, 47) or 51% (IQR 20%-98%) of their actual bladder capacity, while the median PVR for those children with a sustained detrusor contraction was 18 ml (IQR 5, 46) or 33% (IQR 27%, 98%) of their actual bladder capacity. Intraoperative bladder width and bladder dome to bladder neck length did not correlate with the presence of voiding via a detrusor contraction (p = 0.64). DISCUSSION: We present the first study assessing early UDS finding of detrusor contraction in BE patients after CPRE. In our cohort, 61.5% of patients were able to generate a sustained detrusor contraction on UDS which is a higher percentage than has been reported in previous series. A difference in initial surgical management may account for these findings. CONCLUSION: At short term follow up, the majority of children in our cohort were able to produce sustained detrusor contractions sufficient to generate a void per urethra with a modest post void residual volume. Long-term follow-up and repeated UDS will be needed to track detrusor contractility rates, bladder capacities, compliance, post void residuals and ultimately continence rates over time.