OP‐9 MODULATION OF THE RECTOANAL INHIBITORY REFLEX IN PATIENTS WITH MYELOMENINGOCELE WITH AND WITHOUT BLADDER AUGMENTATION

Abstract

Introduction:Some patients with myelomeningocele need bladder augmentation (augmentation cystoplasty). The aim of this study was to evaluate the relationship between the bladder augmentation and the rectoanal inhibitory reflex (RAIR) modulation in patients with myelomeningocele. The modulation of the anorectal inhibitory reflex in accord the use of oxybutynin chloride was also evaluated.Methods:It is a cross‐sectional and comparative study. We studied a convenience sample consisting of 24 children and adolescents with myelomeningocele aged between 4 and 18 years. Ten of these 24 patients had surgery to expand the bladder. Anorectal manometry of perfusion were performed with 8‐channel radial catheter (Dynamed®) in latex free protocol. The evaluation of the (RAIR) modulation was determined by inflating the balloon with 20 mL of air in rectal. The RAIR modulation was determined by duration (seconds) and amplitude (% relaxation) of RAIR.Results:RAIR was present in all the patients. The duration of the RAIR (seconds) with 20 mL and 40 mL was similar in the both groups, with or without bladder augmentation (27.11 ± 11.95; 27.37 ± 9.29; p = 0.953 and 30.32 ± 7.30; 32.08 ± 10.13, p = 0.653). The RAIR amplitude with 20 mL and 40 mL was higher in the patients with bladder augmentation than in patients without bladder augmentation (63.87 ± 24.58; 82.31 ± 15.94, p = 0.036 and 68.06 ± 14.80;88.93 ± 16.31, p = 0.004). The patients who used oxybutynin chloride presented higher amplitude (% relaxation) in relation those did not used this drug, with 20 mL (80.91 ± 15.37 and 65.21 ± 25.73; p = 0.074) and 40 mL (85.78 ± 15.96 and 73.05 ± 19.29; p = 0.084), however, the statistic evaluation did not reach significance.Conclusions:The RAIR modulation is different between patients with and without bladder augmentation. The use of oxybutynin chloride also appears to interfere in the RAIR, increasing its amplitude.