Bladder Augmentation in the Pediatric Neuropathic Bladder

0022-5347 /83/1293-0552$02.00/0 Vol. 129, March

THE JOURNAL OF UROLOGY

Printed in U.S.A.

Copyright© 1983 by The Williams & Wilkins Co.

BLADDER AUGMENTATION IN THE PEDIATRIC NEUROPATHIC BLADDER EVAN J. KASS AND STEPHEN A. KOFF From the Department of Pediatric Urology, and Child Health and Development, Children's Hospital National Medical Center and Department of Urology, George Washington University School of Medicine and Health Sciences, Washington, D. C., and Department of Surgery, Section of Urology, University of Michigan Medical Center, Ann Arbor, Michigan

ABSTRACT

Augmentation enterocystoplasty was used as an aid to reconstruction of the urinary tract and undiversion in 14 children with neurogenic bladder dysfunction. The long-term results have been excellent in children in whom an effective program of clean intermittent catheterization has been possible. The elements and the importance of the preoperative evaluation are discussed. During the last decade the techniques and principles involved in the reconstruction of the urinary tract in children who had previously undergone urinary diversion have become well established.1· 2 More recently, these same techniques, when coupled with clean intermittent catheterization, have been extended to include children with neurogenic bladder dysfunction. 3• 4 An essential component of patient selection for undiversion or reconstructive surgery is the presence of an adequate bladder capacity. Although many children with defunctionalized bladders have small capacities upon initial assessment, with time most will expand to a reasonable capacity and provide an effective storage reservoir. 5 Unfortunately, there are some children with persistently small capacity neurogenic bladders secondary to fibrosis or severe detrusor hyperreflexia unresponsive to pharmacologic manipulation who have heretofore been excluded from consideration for reconstructive surgery. Herein we describe the use of augmentation cystoplasty as an aid to reconstructive surgery and undiversion in 14 children with neurogenic bladder dysfunction. MATERIALS AND METHODS

There were 9 girls between 4 and 17 years old, and 5 boys between 8 and 16 years old with documented neurogenic bladder dysfunction, recurrent febrile urinary tract infections and evidence of high grade vesicoureteral reflux. Of these children 12 had undergone urinary diversion 3 to 14 years previously, and 2 had bilateral vesicoureteral reflux and recurrent febrile urinary tract infections but had not yet undergone urinary diversion. The preoperative evaluation included a careful and complete history and physical examination, with particular emphasis placed on the neurologic status of the child as well as an attempt to detect any social or psychological problems that might preclude strict adherence to a program of clean intermittent catheterization. Radiographic studies included excretory urograms (IVPs) and cystograms, as well as loopograms in those individuals with cutaneous urinary diversions. The upper urinary tracts were normal in 4 children and demonstrated calicectasis, hydronephrosis and/or parenchymal scarring in the remaining 10. All children had stable renal function with creatinine clearance >40 ml. per minute per 1.73 M. 2 • Cystoscopy and urodynamic studies were performed preoperatively in all patients and the findings were similar in each child. The bladder capacity varied between 15 and 75 cc, at which point the intravesical pressure increased rapidly. The use of anticholinergic medications and/or attempts at hydraulic bladder distension during a period of weeks or months did not increase the bladder capacity nor alter the pattern of the pressure volume curve in these children. Electromyography of Accepted for publication June 30, 1982.

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the periurethral striated musculature was performed on each child using monopolar needle electrodes and in each instance there was evidence of good electrical activity present. After the initial evaluation clean intermittent catheterization was initiated with the catheterizations being performed every 3 to 4 hours. The children with defunctionalized bladders were instructed to fill the bladder to capacity with water at the time of each catheterization to help assess their potential for continence. SURGERY

Three children with a colon conduit without reflux had the conduit detached from the skin, opened extensively along its antimesenteric border and anastomosed directly to the widely spatulated bladder to provide a wide anastomotic site (fig. 1). Five children with intestinal conduits with reflux had a single ureter reimplanted into the bladder in an antireflux manner and the opposite ureter was managed by a transureteroureterostomy. The conduit was then opened completely along its antimesenteric border, fashioned into a cup patch and anastomosed to the bladder. A psoas hitch was used to remove all tension from the ureteroneocystostomy (fig. 2). Three children with cutaneous vesicostomy underwent urinary undiversion by means of a bladder augmentation with a colonic segment and simultaneous ureteroneocystostomy. An IVP of 1 patient 5 years after vesicostomy for management of hydronephrosis secondary to vesicoureteral reflux is seen in figure 3, A, and the IVP and cystogram 3 years following reimplantation and colonic augmentation are illustrated in figure 3, B and C. One child with numerous failed urinary diversions presented with a permanent nephrostomy tube in the right kidney and a nonfunctioning left kidney with multiple calculi. The right ureter had been damaged severely by previous surgery and was atretic. An ileocecal segment was used with the ileum anastomosed to the renal pelvis and the cecum was used to augment the bladder. Subsequently, left nephrectomy was performed (fig. 4). The 2 children who had not undergone a previous urinary diversion were managed initially with antireflux surgery but postoperatively they had progressive hydronephrosis despite an adequate catheterization program. The hydronephrosis resolved rapidly following insertion of an indwelling Foley catheter. Bladder augmentation was accomplished in both children with a colonic segment 6 months after reimplantation. RESULTS

In 13 of the 14 children the radiographic appearance of the upper urinary tracts as well as the renal function studies have remained stable. Each child has remained continent provided

that intermittent catheterization was nDod·A·a~ at Lj,-hour intervals. Bacilluria has been present periodically in all children despite continuous antimicrobial medication. However, febrile minary tract infections have occurred only once in each of 2 patients. Vesicoureteral reflux has persisted postoperatively in the l child in whom an ileocecal segment was used for undiversion. No other child has demonstrable reflux, including the 2 who had febrile episodes. Two children have required sodium bicarbonate for the management of mild metabolic acidosis. All children have been followed postoperatively for l to 5 years, an average of 2.6 years. Two major complications have occurred. In l child a mechanical small bowel obstruction developed postoperatively that required surgical lysis of adhesions. An ll~year-old boy did well postoperatively for l year but then discontinued intermittent catheterization. Renal failure and severe metabolic acidosis occurred, and a large mucous ball developed in the bladder. He was managed by exteriorizing the segment of the colon used in the augmentation as a temporary urinary diversion, and an IVP and renal function returned to preoperative levels. Mucous production has not been a problem in any other child. DISCUSSION

The urodynamic evaluation is an essential part of each assessment and the most important aspect of such testing is the ability to the potential for urinary continence. Periodic into the bladder to deterrnine the amount of fluid

that can be stored without is helpful in asi;essrn,g sphincter function of children an adequate bladder capacity but in those with a small hyperreflexic bladder the results have often proved to be misleading. Similarly, urethral pressure profilometry has provided little useful predictive information on individuals with such small capacity bladders. The ·most reliable indicator of future urinary continence in these children has been the finding of electrical activity in the periurethral striated musculature as determined by needle electromyography. In our total experience with children managed by intermittent catheterization satisfactory continence has been possible in >95 per cent in whom electrical activity has been present but in only 50 per cent in whom it was not. We consider the presence of electrical activity in the external sphincter to be a requirement for patient selection and in all of the children thus selected for augmentation or undiversion continence has been achieved. The evaluation of any individual with a neurogenic bladder for undiversion or reconstructive surgery must include a careful assessment of the potential for that individual or the family to perform intermittent catheterization. We routinely institute a trial of intermittent catheterization for several weeks or months prior to undiversion to allow the patient to understand fully what is involved in the long-term usage of intermittent catheterization. Our worst complication occurred in a child who decided to discontinue the catheterization program and, sub-

OPENED BLADDER

ATTACHING BOWEL CAP TO BLADDER Flf~ISHED PROCEDURE

FIG. L Urinary undivemion using colon conduit with reflux

FIG. 2. Technique used to fashion intestinal segment into cup patch

Fm. 3. A, preoperative IVP. B, IVP 3 years after undiversion. C, cystogram 3 years after undiversion

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KASS AND KOFF

Fm. 4. Ileocecal segment used for undiversion to replace entire ureter and augment bladder. sequently, progressive hydronephrosis and azotemia developed, necessitating a urinary diversion as a life-saving measure. In those children in whom the catheterizations were performed regularly no long-term complications have been encountered and intestinal mucous production has not caused any difficulties nor did it require any special treatment. The surgical technique of augmentation enterocystoplasty has been well described and may be applied to individuals with neurogenic bladder dysfunction without modification. 6- 11 In our patients with neurogenic bladder dysfunction either colonic or ileal segments have been used with equal success. However, at least 20 to 25 cm. of intestine should be selected so that the capacity of the bladder created will be approximately 250 to 300 ml. It is essential that the bladder be almost bivalved and that the intestinal segment be formed into a cup patch or opened extensively along its antimesenteric border to assure a wide anastomotic site and avoid a concentric stricture at the bowel-bladder junction. We did not attempt to excise any segment of the bladder even in individuals with severely hyperreflexic bladders and no complications related to the residual bladder tissue have been encountered. The long-term complications of permanent urinary diversion have been evident for some time and, with the increased acceptance and success of clean intermittent catheterization, few children should be considered seriously for such surgery. However, there remains a group of patients in whom vesicoureteral reflux, hydronephrosis or severe detrusor hyperreflexia is not easily managed and urinary diversion might initially appear to be a reasonable option. It is these individuals in whom the lessons learned from undiversion provide new alternatives of management that may reduce the need for urinary diversion even further. Patients with vesicoureteral reflux and neurogenic bladder dysfunction can be managed initially by intermittent catheterization and antimicrobial medications. Should antireflux surgery become necessary it can be performed successfully even in children with neurogenic bladder dysfunction. 12 Bladder augmentation is a particularly attractive alternative in children with a small capacity or a severely hyperreflexic bladder unresponsive to anticholinergic medication because it allows the creation of an adequate capacity low pressure urinary reservoir. If vesicoureteral reflux is also present the ureteroneocystostomy should be performed at the same time as the enterocystoplasty

to obviate the need for future antireflux surgery and to avoid the potential development of any problems related to recurrent bacilluria or excessive intestinal mucus production. Hydronephrosis in the absence of reflux will usually resolve following bladder augmentation and in our experience it has not required further surgical intervention. Metabolic acidosis developed postoperatively in 2 children with bilateral renal damage and impaired renal function. However, an additional 8 patients with similar renal involvement failed to have any electrolyte disturbances. The degree of preoperative renal insufficiency did not appear to be a prognosticator of future electrolyte problems following the addition of an intestinal segment to the bladder. It may be that the frequent and complete bladder emptying effected by intermittent catheterization reduces the potential for such a problem. The renal function has not deteriorated in any individual who has adhered to the clean intermittent catheterization program regardless of the degree of renal impairment present preoperatively. Presently, we do not require any absolute level of renal function to consider an individual for urinary undiversion, although we have not had occasion to undivert any individual with a creatinine clearance <40 ml. per minute per 1.73 M. 2 • The 1 essential element necessary for the success of any reconstructive endeavor in children with neurogenic bladder dysfunction is the institution of an effective program of clean intermittent catheterization. It is imperative that the bladder be emptied completely at regular intervals and bladder overdistension as well as elevated intravesical pressures be avoided if such surgery is to be successful. However, once an effective program of intermittent catheterization is established, then the principles of urinary tract reconstructive surgery can be applied to those individuals with neurogenic bladder dysfunction just as they would in children with normally functioning bladders. REFERENCES 1. Hendren, W. H.: Reconstruction of previously diverted urinary

tracts in children. J. Ped. Surg., 8: 135, 1973. 2. Dretler, S. P., Hendren, W. H. and Leadbetter, W. F.: Urinary tract reconstruction following ileal conduit diversion. J. Urol., 109: 217, 1973.

3. Perlmutter, A. D.: Experiences with urinary undiversion in children with neurogenic bladder. J. Urol., 123: 402, 1980. 4. Bauer, S. B., Colodny, A. H., Hallet, M., Khoshbin, S. and Retik, A. B.: Urinary undiversion in myelodysplasia: criteria for selection and predictive value ofurodynamic evaluation. J. Urol., 124: 89, 1980.

5. Schmaelzle, J. F., Cass, A. S. and Hinman, F., Jr.: Effect of disuse and restoration of function on vesical capacity. J. Urol., 101: 700, 1969.

6. Goodwin, W. E., Winter, C. C. and Barker, W. F.: "Cup-patch" technique of ileocystoplasty for bladder enlargement or partial substitution. Surg., Gynec. & Obst., 108: 240, 1959. 7. Gil Vernet, J. M.: Technique for construction of a functioning artificial bladder. J. Urol., 83: 39, 1960. 8. Kuss, R., Bitker, M., Camey, M., Chatelain, C. and Lassau, J. P.: Indications and early and late results of intestino-cystoplasty: a review of 185 cases. J. Urol., 103: 53, 1970. 9. Homsy, Y. L. and Reid, E. C.: Ileocystoplasty. Urology, 4: 135, 1974. 10. Smith, R. B., Van Cangh, P., Skinner, D. G., Kaufman, J. J. and Goodwin, W. E.: Augmentation enterocystoplasty: a critical review. J. Urol., 118: 35, 1977. 11. Dounis, A. and Gow, J. G.: Bladder augmentation-a long term review. Brit. J. Urol., 51: 264, 1979. 12. Kass, E. J., Koff, S. A. and Diokno, A. C.: Fate of vesicoureteral reflux in children with neuropathic bladders managed by intermittent catheterization. J. Urol., 125: 63, 1981.

EDITORIAL COMMENT Augmentation of the neurogenic bladder adds another dimension to urinary tract salvage or reconstruction, extending the advantages of an intact urinary tract and continence to additional children who might otherwise be management failures from intractable hyperreflexia or a