Effect of baseline obesity and postoperative weight gain on the risk of channel revision following continent catheterizable urinary channel surgery.

OBJECTIVE: Prior studies suggest that obese patients are at increased risk for complications following continent catheterizable urinary (CCU) channel surgery. We hypothesized that postoperative weight gain increases the risk of channel angulation, difficulty catheterizing, and possible channel perforation requiring subfascial revision. The purpose of this study was to evaluate whether baseline obesity or becoming overweight/obese postoperatively was associated with a greater risk of subfascial revision. METHOD: We reviewed retrospectively an institutional database of patients who underwent CCU channel surgery between the ages of ≥2 and <20 years from January 1990 to May 2013, excluding those with continent urinary reservoirs, continent vesicostomies, and those without body mass index (BMI) data. We collected data on patient/procedure characteristics, baseline/most recent BMI, and subfascial revision(s). We used Cox proportional hazard multivariable regression to assess the association of being overweight/obese at baseline (≥85% BMI) with time to first subfascial revision, and Fisher's exact test to compare rates of subfascial revision between those who became overweight/obese and those who did not. RESULTS: Of the patients, 328/501 (65.5%) had baseline and post-baseline BMI data available: 53.4% male, 90.6% white, median age 7.4 years; median follow-up 76.4 months. Of the 328 patients, 38 (11.6%) had subfascial revisions. Baseline BMI data were available for 378 patients, and, of these, 130 (34.4%) were overweight/obese at baseline. Overweight/obese patients were more likely to undergo umbilical Monti (10% vs. 8.1%), non-umbilical spiral Monti (33.8% vs. 13.7%), and spiral umbilical Monti channels (13.8% vs. 7.3%) versus normal/underweight patients (p < 0.0001). From a multivariable Cox proportional hazard model controlling for age, BMI category, diagnosis, and ambulatory status, the hazard of subfascial revision for spiral umbilical Monti channels was 2.1× that of other channels (hazard ratio (HR) 2.1 [95% CI 1.2-3.8], p = 0.01). Fifty-one out of 328 patients (15.6%) became overweight/obese postoperatively, with 7.8% having a subfascial revision vs. 12.3% of those whose weight category decreased or remained stable (p = 0.3) (Table 1). CONCLUSIONS: Patients who were overweight/obese at baseline were more likely to have channels constructed that are at the highest risk of subfascial revision. Patients who became overweight/obese postoperatively were not at greater risk of subfascial revision. Limitations include potential bias because of differential follow-up and inaccuracy of BMI percentile as a measurement of obesity.

Does endoscopy of difficult to catheterize channels spare some patients from formal open revision?

INTRODUCTION: Patients with continent catheterizable channels (CCC) may develop difficulty catheterizing postoperatively. In complex cases, endoscopic evaluation with indwelling catheter placement may be indicated, but the risk factors for subsequent formal channel revision are not well defined. The purpose of this study was to determine the risk factors for formal channel revision after attempted endoscopic management of difficulty catheterizing. MATERIALS AND METHODS: We performed an IRB-approved retrospective review of pediatric (<21 years old) patients undergoing CCC construction at our institution from 1999 to 2014 to identify patients who underwent endoscopy for difficulty catheterizing. Fisher's Exact test was used for categorical data and Mann-Whitney U test for continuous variables to examine the association between endoscopic intervention and subsequent formal revision. RESULTS: Sixty-three of 434 patients (14.5%) underwent at least one endoscopy for reported difficulty catheterizing their CCC, with 77.8% of these requiring additional intervention during endoscopy (catheter placement, dilation, etc.). Of these, almost half with functioning channels (43.5%, 27/62) were managed successfully with endoscopy without formal revision; six (22.2%) of whom underwent more than one endoscopy. These 27 patients continued to catheterize well at a median follow-up of 3.2 years (interquartile range 2.0-6.0). Patients requiring revision had a median of 1.7 years between CCC creation and first endoscopy, versus 1.6 years in those who were not revised (p = 0.60). There was no statistically significant difference between revised and non-revised channels in terms of patient age at CCC creation, underlying patient diagnosis, status of bladder neck, stomal location, or channel type (p ≥ 0.05) (see Table). CONCLUSION: Approximately half of our patients did not require a formal channel revision after endoscopic management. We did not identify any specific risk factors for subsequent formal revision of a CCC. We recommend performing at least one endoscopic evaluation for those with difficulty catheterizing prior to proceeding with formal open revision.

Long-term renal functional outcomes after primary gastrocystoplasty.

PURPOSE: We assessed long-term renal function, morbidities and mortality in 50 patients who had undergone primary gastrocystoplasty at our institution. MATERIALS AND METHODS: We retrospectively reviewed patients 21 years or younger who had undergone primary gastrocystoplasty between 1984 and 2004. Patients who underwent secondary gastrocystoplasty or primary composite augmentation or had cloacal exstrophy were excluded. Primary outcome was progression to end-stage renal disease. Secondary outcomes included mortality, bladder malignancy, hematuria-dysuria syndrome, electrolyte abnormalities and surgical revisions. RESULTS: Of 50 patients who had undergone gastrocystoplasty 35 met inclusion criteria. Median age was 9.4 years and 60% of the patients were male. Median followup was 19 years (IQR 11 to 25). Of the 35 patients 15 (43%) had normal preoperative estimated glomerular filtration rate and 5 (14%) had stage 2, 10 (29%) stage 3 and 5 (14%) stage 4 chronic kidney disease. Five of the 15 patients with stage 3 or 4 chronic kidney disease improved to normal estimated glomerular filtration rate, 1 remained with stage 3 disease and 9 progressed to end-stage renal disease. In 1 patient with normal estimated glomerular filtration rate end-stage renal disease developed following an episode of septic shock due to osteomyelitis. Seven patients in the cohort (20%) died, with 1 each dying of ventriculoperitoneal shunt infection, pneumonia, end-stage renal disease, complications of pregnancy and unknown cause, and 2 patients dying of septic shock due to urinary tract infection. There were no bladder malignancies. Hematuria-dysuria syndrome developed in 9 patients (24%). Eight patients (23%) underwent surgical revision. CONCLUSIONS: The majority of patients had preserved or improved renal function after gastrocystoplasty. There were no deaths attributable to gastric augmentation and no bladder malignancies. Approximately a fourth of patients required surgical revision.