Early evolution of bladder emptying after myelomeningocele closure

Objectives. To analyze bladder emptying in newborns with Spina bifida after closure of the myelomeningocele defect. Manipulation of the spinal cord an d nerve roots results in temporary changes in bladder function in many sett ings. Methods. We reviewed 62 consecutive newborn patients who underwent closure of a myelomeningocele defect at our institution from January 1990 to Decemb er 1997. We examined the catheterized urine volumes obtained before and aft er closure, radiographic and urodynamic studies, and the subsequent need fo r intermittent catheterization. Poor bladder emptying was defined as most c atheterized urine volumes greater than 10 mL (20% of expected bladder capac ity). Adequate follow-up was available for 54 patients for a period of 4 to 96 months (mean 42). One patient with posterior urethral valves was exclud ed from the study, leaving 53 for evaluation. Results. Of the 53 patients, 4 with high outflow resistance and dyssynergy never emptied the bladder adequately before or after closure. Of the remain ing 49 patients, 6 (12%) emptied well immediately after the myelomeningocel e repair. In the other 43 (88%), the bladder did not empty as well after cl osure. The mean volume obtained with catheterization after closure was 20 m L, significantly higher (P <0.001) than the mean volume obtained before rep air (6.5 mL) or after resumption of better spontaneous emptying (4 mL). Int ermittent catheterization done for poor emptying was required for an averag e duration of 11 days (range 2 to 42). Of the 43 patients with poor emptyin g immediately after closure, 32 (74%) required catheterization for 2 weeks or less; the remaining 11 (26%) required catheterization for 2 to 6 weeks. Despite the relatively early resumption of good emptying, numerous patients (19 of 49) required additional intervention (clean intermittent catheteriz ation or vesicostomy) before attempts to toilet train. Conclusions. A clinical pattern similar to spinal shock does occur in most newborns after closure of a myelomeningocele defect. Resumption of near-com plete emptying usually occurs less than 2 weeks after repair but may requir e up to 6 weeks. (C) 2001, Elsevier Science Inc.