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Neurogenic Bladder, Modern Treatment

Tom P.V.M. de Jong
Utrecht, The Netherlands

 

Abstract 

Renal damage and renal failure are still reported as complications of spina bifida. We have been using a protocol for spina bifida treatment over the last 16 years that minimises renal scarring to 0,5% of all patients. Moreover, the majority of patients are continent for urine when going to primary school. A pro-active treatment of detrusor and sphincter overactivity from birth on is mandatory to obtain such results since upper urinary tract changes occur in the first months of life. This implies that every neonate with spina bifida is treated by clean intermittent catheterisation and pharmacological suppression of detrusor overactivity from birth on. Later in life, therapy can be tailored to the urodynamic specifications of bladder and sphincter. For children with urinary incontinence, surgery to become dry has been routinely offered around the age of 5 years. We have been using rectus abdominis sling suspension of the bladder neck with good results, both in male and in female patients. As an alternative for ileocystoplasty, detrusorectomy can be done to lower intravesical pressures provided that adequate bladder capacity is present.

 

Correspondence

Tom P.V.M. de Jong  

University Children’s Hospital, UMCU

Utrecht, The Netherlands.
P.O.Box 85090 / 3508AB Utrecht;

e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it. .

 

Introduction

The incidence of spina bifida worldwide still ranges from 0,3-4,5 per 1000 births. Renal scarring and renal failure are important issues over years in spina bifida literature with reported death, due to renal failure, in the first year of life up till 20%. The incidence of renal damage in not-adequately-treated patients with overactive pelvic floor is nearly 100%. Important is to realise that the renal damage starts early in life, within the first six months. In contrast to a few decades earlier we can assure parents of children with a neurogenic bladder that preservation of renal function can be guaranteed, provided they comply with the treatment regime (1,13).

To prevent renal damage, treatment of a neurogenic bladder should start immediately after birth. Modern treatment gives us the opportunity to convert a highpressure bladder with functional urethral obstruction based on neuropathic detrusor/sphincter dyssynergia into a lowpressure reservoir that is safe for the upper tracts (14,24). The objectives in the urological management of patients with a spina bifida are:

  1. Preservation of renal function;
  2. Quality of life, preferably with urinary dryness at school age and
  3. Independence at older age considering bladder and bowel management.

A modern protocol for the management of spina bifida

To preserve renal function low bladder pressures must be maintained from birth on. To learn whether a child is at risk for high detrusor pressures the status of the pelvic floor activity must be assessed shortly after birth. At first presentation after birth inspection of the anal sphincter, closed or open, gives an impression of the status of the pelvic floor: overactive or paralysed. Approximately 50% of the children with spina bifida aperta and 25% of children with occult spinal dysraphism have a detrusor/sphincter dyssynergia that carries a serious risk for early upper tract damage by high bladder pressures and UTI’s. Important is the knowledge that after closure of the back, the behaviour of the pelvic floor can change from paralysed into overactive in the first 2-3 months of life. It is because of this that we delay the first Urodynamic Study (UDS) till 2 months after birth.

In our protocol, all newborn patients are put on clean intermittent catheterisation (CIC), oxybutynin and chemoprophylaxis (trimethoprim 2mg/kg once daily), immediately after closure of the back. By doing this we have been able to maintain low, safe pressures in the lower urinary tract in most patients. Bladder volume and bladder compliance, in most cases, remain good over years and this policy has reduced the need for bowel augmentation of the bladder in cases of overactive pelvic floor from 90% in the past to less then 5%.

Overactive Pelvic Floor

Patients with an overactive pelvic floor generally become dry for urine from birth on with oxybutynin and CIC. UDS are done yearly to control bladder overactivity, bladder capacity and compliance. Ultrasound control is done for upper tract dilatation and renal growth. A wait and see policy is maintained when bladder capacity for age is normal and end-filling detrusor pressures are 30 cm’s H 2 O or less. When the compliance of the bladder is insufficient, with end-filling pressures more then 30 cm’s, an autoaugmentation or detrusorectomy can be done to reduce the pressure. When serious overactivity combines with a bad compliance and a low capacity, augmentation by ileocystoplasty or colocystoplasty is inevitable. Both operations can be done at any age and can be combined with other procedures to obtain better urinary continence, to facilitate CIC and to reduce UTI’s (reflux) (15,18). 

Paralysed Pelvic Floor

Patients with a paralysed pelvic floor are incontinent for urine. Their upper tracts are safe as long as the paralytic pelvic floor is left untreated. They need bladder neck surgery to obtain continence. When bladder capacity and bladder compliance are insufficient this surgery can be combined with autoaugmentation of the bladder or (rarely) with clam ileocystoplasty or colocystoplasty. If detrusor overactivity is found at UDS we do treat the patients with antimuscarinics notwithstanding safe detrusor pressures to ensure capacity of the bladder.

Clean Intermittent Catheterisation, CIC

This has been introduced for neurogenic bladders in 1972. (26) The parents and other caregivers do CIC in the first 8-9 years of life, by the children after this age when sufficient dexterity exists. After birth CIC is done with selflubricating 8Fr. catheters. Size of the catheter is adapted to patient’s age and the aim is always to use the largest possible catheter to obtain optimal bladder emptying. When CIC is done through an umbilical stoma one must realise that a risk exists for incomplete emptying and UTI’s. In those cases we advise to connect a tube to the catheter that drains into a bowl on the floor. The tube then drains the bladder by suction. The tube is obtained by cutting the bag from a standard urine collecting system. The tube can simply be rinsed with water after each use. When catheter costs are a problem one can use a metal catheter for girls. Older girls often prefer a metal catheter that is cleaned once a day. In some countries, where the insurance companies do not pay for catheters, the patients use the self-lubricating catheters for a week without apparent extra UTI’s.

Treatment of detrusor over activity

Life-long suppression of detrusor over activity is needed in patients with an overactive neuropathic bladder. In some cases, overactivity can be treated surgically by detrusorectomy or ileocystoplasty. In spina bifida, rhizotomies to cure over activity have not been used routinely but may have a future. Ideally we have dreamt to start a protocol with neonatal rhizotomies at the first back closure but practical and ethical considerations have prevented us doing this up till now. Antimuscarinic therapy is the actual golden standard for pharmaceutical therapy of neuropathic detrusor overactivity. Oxybutyin has proven to be cheap and effective and can be used both orally, intravesically and by skin-pads. It has the disadvantage that a relative contraindication exists in tropical temperatures because of the negative effect on transpiration and regulation of body-temperature. Many central nervous side effects of oxybutynin can occur that force to change treatment. Central side effects are less frequent when other then oral routes are used for administration of the drug. Several new antimuscarinic agents have been introduced in the last decade that may prove their value for spina bifida patients in the near future. An alternative for antimuscarinic therapy is repeated injection therapy of the bladder with 300 units of botulinum toxin. This suppresses detrusor contractions effectively for several months. Injections have to be repeated at 6-9 months interval. The long-term effect yet has to be clarified. (19,20).

Incontinence surgery

Patients with a paralytic pelvic floor need bladder neck surgery to reach continence. Many surgical options exist. We have a standard policy to do an abdominoperineal puboprostatic sling procedure in male patients and a transvaginal sling procedure in females. When, after a sling procedure, some leakage persists this is cured by injection of a bulking agent in the bladder neck. Optimal results are obtained with bulking agents in the bladder neck when the needle for injection is passed into the bladder neck through suprapubic puncture with transurethral endoscopic visual control. Up till now we have used silicon grains in povidone (Macroplastique) as a bulking agent. The polymer Deflux seems to offer a good alternative because it is easier to inject. In our hands, Deflux does not work when CICis needed to be done through the same channel. 

Sling suspension in male patients

Results of sling suspension of he bladder neck in boys with neuropathic sphincter incompetence, compared to girls, in the literature, vary more widely. To wrap the sling around the bladder neck the plane between the bladder neck/prostate and the rectum must be developed. Three possible techniques have their specific advantages and disadvantages. Firstly, from the abdominal wound, one can open the pelvic diaphragm left and right and dissect a pathway for the sling bluntly around the bladder neck. Disadvantage of this technique is the risk to pass into the prostatic urethra with the right angle that is used to feel the way around. Experienced urologic surgeons do not take this argument seriously but fact is, in practice, that most surgeons perform this operation with a relatively low frequency of a few cases a year.

Secondly, the abdominoperineal approach to develop the plane between the bladder neck and the urethra. With gauze in the rectum for better identification an inverted U incision is made in the perineum. The centrum tendineum of the pelvic floor is opened in the mid-line and by blunt dissection with a finger the plane between prostate and rectum is developed with the transurethral ballooncatheter as a landmark. Pulling the catheter and feeling the position of the balloon can identify the level of the bladder neck. Mid-line connections between the prostate and the rectum are cut sharply. With the index finger following the rami of the pubic bone the pelvic diaphragm is perforated bilaterally and a strong vessel loop is passed around the bladder neck from left to right. The sling can subsequently be pulled through and fixed to the contralateral pubic bone. Most important advantage of this procedure are the short time, approximately 20 minutes, that is needed to develop the plane around the bladder neck, and the fact that the bladder does not need to be touched at all (21).

A third way to find the path around the bladder neck has recently been proposed by Lottmann. The complete bladder is dissected from the peritoneum and the rectum until only the urethra and both ureters with the vascular pillars fix it. The sling can easily be passed around under direct visual control and exactly at the level of the bladder neck (22). It is difficult to determine which of the 3 approaches is the best. All 3 have enthusiastic followers. We have had 2 urethral defects by 2 experienced surgeons in a small series of the abdominal approach going directly around the bladder neck. We have had 1 urethral defect leading to bladder neck closure in 50 abdominoperineal-operated patients. My personal experience to the Lottmann approach is limited to 3 successful cases and, because of operative time and for fear of limited bladder vascularisation, we have dropped back on the abdominoperineal approach.

The amount of tension that needs to be put on the sling is an important subject. In the past, we have tried to adjust tension by measuring urethral pressures and leak-point pressures during surgery without significant outcome. Nowadays, we determine the tension on the sling by measuring the ability to pass a relatively large Foley catheter past the sling, for example a 12 Fr. catheter in a 7-year-old boy. In selected cases, patients with anal atresia after prior rectal pull-through surgery, an abdominal approach can be considered necessary to pass around the bladder neck. In a series of 14 abdomino-perineal operated patients, published in 1999, continence was achieved in 100%; one case needed subsequent injection of a bulking agent to achieve continence. Important is that in this series erectile function of the penis proved to be preserved after sling suspension. False routes after sling suspension are a risk. Out of approximately 50 male cases we have had to construct a catheterisable stoma in 5, 4 because of a false route, 1 because of a huge congenital prostatic cyst.

Sling suspension in females

Sling suspension of the bladder neck in female subjects averages good results concerning urinary continence. Several ways exist to find the way around the bladder neck in girls. The standard well-known technique is to identify the level of the bladder neck, by feeling the balloon of a transurethral Foley catheter and develop the plane between the bladder neck and the anterior vaginal wall from above. This procedure can be very difficult in girls with severe spine deformities. A certain risk to enter the urethra or the bladder neck when going around is always present, also in patients with normal anatomy. To avoid this risk, in post puberty female patients, many opt for the possibility to incise the vaginal wall at the level of the bladder neck and bring the sling around under direct visual control. First in prepubertal girls and later in all cases we have adopted the habit to put the sling through the vagina. This method has 2 advantages: the risk for bladder neck lesions does not exist and there is less chance for sling erosion. Sling erosion risk is higher in spina bifida patients then in patients with stress incontinence because the sling must be tightened more strongly in neuropathic sphincter incompetence.

Description of the procedure in 24 cases

Patients are operated under antibiotic prophylaxis with amoxicillin/clavulanic acid and gentamycin. Flushing the vagina with povidone/iodine 10% solution is done as vaginal toilet. Most patients are operated through a transverse lower abdominal incision with longitudinal opening of the rectus abdominis fascia in the midline. Patients that have an ileocystoplasty as well are operated through a longitudinal lower abdominal midline incision. A 10-15 cm long and 2-cm wide paramedian strip of the rectus abdominis fascia is made leaving the caudal end fixed to the pubic bone. In patients that had an earlier transverse incision of the rectus fascia a 2-cm wide strip of externus abdominis fascia is harvested running from the pubic bone to the anterior superior iliac spine. The bladder neck and anterior vaginal wall are identified with a transurethral balloon catheter and freed, comparable to the preparation that is done for a Burch-type colposuspension. A metal clamp is introduced into the vagina and used to lift the anterior vaginal wall left and right of the bladder neck. Using electrocautery, 2 small holes are made into the vagina and a vessel loop is passed around the bladder neck through the holes. Because the majority of the patients are prepubertal and no patient has given birth before the operation there is not enough room in the vagina to attempt creating a submucosal tunnel in the anterior vaginal wall. The fascia sling is fixed to the vessel loop and passed through the holes. The sling is passed bluntly through the contra lateral rectus abdominis muscle and overlying fascia and tightly fixed to the tubercle of the pubic bone with strong polyglycolic acid sutures. Tension on the sling before fixing is high leaving one finger between the symphysis and the bladder neck. This is in contrast to sling suspension for stress incontinence, where the sling is hardly tied. In the majority of our patients the sling operation has been combined with other procedures: ileocystoplasty in 5, detrusorectomy in 13, continent catheterisable stoma in 8 and extravesical ureteral reimplant in 3. Patients were treated with low-pressure suction drainage before the bladder for 2-4 days. Bladder drainage is done by transurethral catheter for 7 days, combined with suprapubic catheter in cases of ileocystoplasty. Hospitalisation for the patients without ileocystoplasty was 3 days. The patients that had no catheterisable stoma resumed clean intermittent catheterisation (cic) after 7 days. Special attention is given to teach the patients the changed direction of the urethra when transurethral CICis resumed (23) Of our series of 24, 22 became dry, 19 after the sling suspension and 3 after additional injection of bulking material on the sling. When, for some reason, colposcopy is done a few months after sling suspension the sling appears to be completely covered by vaginal mucosa and cannot be identified anymore.

Catheterisable stomas

The need for transfers from a wheel chair to do CICis the most important indication to make a catheterisable stoma. Sometimes, in male patients, the impossibility to do CICtransurethrally after false routes obviates the need for a stoma. Privacy of the patient is more and more indicated by the parents as a reason to ask for a catheterisable stoma. In patients with a large bladder capacity for age a continent stoma can be constructed from a bladder tube. Patients with a normal bladder capacity can be treated by cutaneous appendicovesicostomy or by an ileal tube (Monti-procedure). The direction of peristalsis from the appendix needs to go in the direction of the bladder. When ileal or colonic bladder augmentation is done at the same time the continent stoma can be constructed from the side or middle part of the gut used to do the augmentation. In selected cases a ureter can be used as a catheterisable stoma. It is of importance that the intravesical tunnel of the tube in the bladder is at least 2 cm’s long. Especially when doing an extravesical implantation of an appendix the risk exists that the tunnel ends up being too short.

In literature, about 50% of complications are described after construction of a catheterisable stoma. These complications are temporary problems in the majority of cases. Stoma stenosis, mostly at skin level is a frequent occurring temporary complication that can be avoided with a silicon or Teflon ‘nail’ left behind in the skin part of the stoma between catheterisations. Stomal leakage of urine can be a frustrating complication. Endoscopic treatment by bulking agents can be tried but often lengthening of the intravesical tunnel or reimplantation of the stoma will be needed. Leaking of the stoma occurs more often in mid-line stoma (umbilicus) than in stoma’s placed on the right side of the lower abdominal wall. The reason is probably that the lateral stoma passes through the rectus muscle and thus, is occluded during abdominal pressure rises because of rectus contraction. Also in midline stoma’s we nowadays pass the stoma through the median margin of one rectus muscle. Stoma stenosis at the level of entrance into the bladder can sometimes be treated endoscopically with success. Also, in those cases, formal reimplantation of the stoma into the bladder will frequently be needed.

Auto-augmentation or detrusorectomy of the bladder

In general, one should not expect much extra capacity but high end filling pressures based on low compliance of the bladder can be reduced to safe values. In selected cases that have surgery to become dry, we also do an autoaugmentation to try and get patients off antimuscarinic therapy with a success rate of approximately 50%. Important factor for success is to identify, open and mark the adventitional layers of the bladder separately before the detrusorectomy and to close this layer meticulously at the end of the procedure. This means that, before starting with detrusorectomy, the detrusor has been freed of all adventitional layers! When a mucosa leak occurs during the operation this is closed with tissue-coll. Cycling of the bladder after detrusorectomy has to start immediately after the procedure to prevent shrinkage and scarring. We do this by maintaining a 20 cm’s H 2 O pressure on day 1, 30 cm’s on day 2 and by clamping the catheter on day 3 for 2 hours, by opening the catheter on day 4 every 3 hours to empty the bladder. Thus optimal expansion of the detrusorectomized bladder is obtained (15). Several authors have reported success by expanding the bladder over a balloon for several days while ensuring drainage of urine by ureteral catheters. We have no experience with this procedure but it could work well in case of leakage. Others have successfully covered the bare part of the mucosa with a demucolised patch of sigmoid colon. Failure has been reported of covering by peritoneum or omentum.

Clam cystoplasty

This is indicated when bladder capacity is too small to reach acceptable numbers of catheterisation/day and/or end-filling pressures are too high for safety of the upper tracts. It is done with ileum or colon. In general 25 cm’s of ileum is used, opened antimesenterically, and constructed in a U-shaped cap. The last 20-cm’s of the ileum are not used to prevent malabsorption of vitamins. In case of a short ileal mesentery, sigmoid colon can be used easily. It is important to avoid the creation of an hourglass bladder by opening the clam anteriorly till the bladder neck, posteriorly up till the trigone. In children, we prefer to bring the bladder extraperitoneally by closing the peritoneum around the vascular pedicle. This extraperitonisation of the bladder brings initially more trouble to reach sufficient bladder capacity but seems to reduce the risk of spontaneous perforation of the bladder. A risk that is prominent in children because of the tendency for bad patient’s compliance with CIC during puberty. We have had, over years, 2 spontaneous leaking ileal bladders out of 6 that had not been put extraperitoneally, 0 spontaneous leaking/rupture in more then 40 other cases with extraperitoneal ileal bladder.

Timing of surgery

No age-related contraindication does exist for any of the operations mentioned above. Thus indication for surgery is made in mutual agreement with the child’s parents or with the patient itself after the age of 11 years. The combination of high bladder pressures with vesicoureteral reflux can sometimes force intervention as early as the first few months of life. We have done the combination of anti-reflux surgery, autoaugmentation of the bladder and transvaginal sling suspension in a 3-month old girl with feverish break-through infections with impeccable follow-up for more than 10 years. We have proven over the years that puberty can safely be passed after sling suspension of the bladder neck, both in females as in males. Parental burden can be an indication to perform a catheterisable stoma. When a child weights 20 kilograms 5 transfers a day for CIC can be too much for a parent with lower back pain.

Finally, the patient’s privacy can be an important factor to construct a stoma for cic. More and more, parents are reluctant to have any caretaker dealing with their child do CIC transurethrally, meaning exposure of the genitalia to strangers several times a day.

Bowel management

The first 2 years of life a wait and see policy is done, often supported by chronic use of laxatives. At the age of 3, bowel management is done with retrograde colonic enemas with success in the vast majority of patients. The rare case that has trouble emptying the rectum with retrograde enemas is offered an antegrade colonic stoma (ACE). Also patient’s choice can be an indication for an ACE. As a separate procedure the simplest way to do an ace is to bring the tip of the appendix to the abdominal skin by laparoscopy. Alternatives are an open procedure with open abdomen for other surgery or, in the absence of an appendix, to create a transverse tube from the colon (left or right) and create a submucosal tunnel to prevent leakage. Many authors have good experiences with several types of buttons that are put into the colon. By doing all this treatment of spina bifida patients can be very successful. In our series, between 1988 and 2001, a 0,5% renal scarring was seen in 146 patients and nearly 100% urinary dryness in patients that opted to be dry.

Alternatives for dealing with the neurogenic bladder

When cerebral function is bad and the patient has no dexterity one can choose for diapers. This needs to be combined with a low-pressure bladder. Good results are obtained by cutaneous vesicostomy. In girls, this can be achieved by making a vesicovaginal fistula by endoscopic cutting into the vagina between the ureteric orifices. Temporary low pressures can be achieved by overdistension of the female urethra. In the male patient, endoscopic external sphincterotomy in the 12 ‘o clock position produces low outlet resistance for 2-3 years and has to be repeated when bladder pressures rise.

Alternatives for the Utrecht protocol

Many surgical alternatives exist to reach urinary continence. Kropp and Pippi Sale developed operations to create a flap valve from the bladder neck. Several authors prefer AMS sphincters to reach continence. The majority of patients still need CIC after AMS sphincter prosthesis. In our hands, Burch-type colposuspension are insufficient for spina bifida girls to reach urinary continence. This is related to the huge intra abdominal pressure that can come with transfers from the wheel chair.

Several groups do not opt for urinary continence at early age and try to maintain safe leak point pressures by regular dilatation of the female urethra, sometimes also of the male urethra after making this possible with a perineal urethral stoma. They sometimes construct a cutaneous vesicostomy for the first years and do an ileocystoplasty when the stoma is closed (24).

We are convinced that early urinary and faecal continence is an important factor for optimal quality of life for spina bifida patients. Another important factor is independence of the patient in hers or his bladder and bowel management. For optimal treatment of this difficult group of patients we control them in a multidisciplinary team with all medical specialities that are needed plus physical therapists, specialised nurses and assistance of a social worker.

 

 

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