A prospective cohort study of assisted bladder emptying following primary cloacal repair: The Children's National experience

Abstract

Introduction/background: Although the combination of bladder dysfunction and upper tract anomalies puts patient with cloaca at risk for renal disease, the rarity of this condition makes it difficult to study empirically. As a high-volume center, we uniquely capture bladder function outcomes following our growing number of cloacal repairs.

Objective: 1) Describe the rates of incomplete bladder emptying following primary cloacal repair (at 2-3 months after repair and last follow up), and 2) identify clinical factors associated with assisted bladder emptying.

Study design: We performed a prospective cohort study of patients undergoing primary cloaca repair by our Children's National Colorectal Center team between 2020 and 2021. The primary outcome was assisted bladder emptying at 2-3 months postoperatively and last visit. Covariables included preoperative characteristics (cloacagram measurements), ARM complexity (moderate = common channel [CC] <3-cm, severe = CC ≥ 3-cm), vesicoureteral reflux (VUR) status, sacral ratio (good ≥0.7, intermediate 0.7-0.4, poor ≤0.4), spinal cord status, means of preoperative bladder emptying, and operative details (age at repair, repair type, & concomitant laparotomy).

Results: Eighteen participants were eligible. A majority had moderate cloaca (78%), VUR (67%), spinal cord abnormalities (89%), and good sacral ratios (56%). Preoperatively, 10 patients were diapered for urine and 8 had assisted bladder emptying. Surgical repairs were performed at a median age of 8 months (range 4-46). Nine (50%) patients underwent urogenital separation (UGS), eight (44%) total urogenital mobilization, and 1 (6%) perineal sparing posterior sagittal anorectoplasty with introitoplasty. Exploratory laparotomy was performed in 7 (39%) patients. At 2-3 months, 7 patients were voiding and 11 required assisted bladder emptying. Median length of long-term follow up was 12 months (range 5-25), and 8 patients were voiding and 10 required assisted bladder emptying. Postoperative need for assisted bladder emptying was significantly associated with assisted bladder emptying preoperatively, a shorter urethra and increasing common channel length, UGS and exploratory laparotomy. Spinal cord imaging findings were not associated.

Discussion: Bladder emptying following cloaca repair is likely a result of congenital function and surgical effects. Indeed, increasingly cloaca complexity requiring UGS and laparotomy was associated with both pre- and post-operative assisted bladder emptying. The lack of association with spinal cord imaging may reflect a divergence between anatomy and function.

Conclusion: Approximately half of patients required assisted bladder emptying in this study. Associated factors included urethral and common channel length, the need for assisted bladder emptying preoperatively, the type of surgical approach and additional laparotomy. Being diapered with seemingly normal voiding prior to surgery did not guarantee normal bladder function postoperatively.

Keywords: Bladder function; Cloaca; Genitourinary reconstruction.