ARTIFICIAL URINARY SPHINCTER IN THE TREATMENT OF URINARY INCONTINENCE: PREOPERATIVE URODYNAMICS DO NOT PREDICT THE NEED FOR FUTURE BLADDER AUGMENTATION

Clinical indications for augmentation in children with neurogenic urinary incontinence following bladder outlet procedures: Results of a 14-year observational study

PURPOSE

We report continence, upper tract changes, and augmentation indications and rates in consecutive patients undergoing bladder outlet surgery without augmentation for neurogenic urinary incontinence.

METHODS

From 2000 to 2007, 37 patients underwent bladder neck sling (BNS), and from 2007 to 2013, 45 patients had Leadbetter/Mitchell bladder neck revision plus sling (LMS), all without augmentation. Mitrofanoff channels were created in all cases. Twenty children with persistent outlet insufficiency underwent bladder neck closure (BNC). All patients had pre- and postoperative urodynamic testing (UD).

RESULTS

Mean follow-up was 60 months after BNS, 38 months after LMS, and 29 months after BNC. Continence (dry, no pads) was achieved significantly more often with LMS versus BNS (66% vs. 37%). There were no significant differences between these patients in preoperative UD % capacity, end filling pressure (EFP), or compliance. Those that became dry had a greater % capacity on postoperative UD, but postoperative EFP was similar between dry and wet LMS and BNS patients. BNC resulted in dryness in 65% of patients, with most incontinence occurring from the Mitrofanoff stoma associated with filling pressures > 40 cm. A total of 10 (12%) children had augmentation, seven after BNC. Clinical indications were end filling pressures > 40 cm plus hydronephrosis ≥ grade 3, and/or persistent incontinence. Need for augmentation was not predicted by preoperative urodynamic parameters. Postoperative UD in those who were augmented showed significantly less % capacity and compliance, and significantly greater EFP, than those not augmented.

CONCLUSIONS

Dryness was achieved in only 33% of BNS versus 66% of LMS and BNC patients. Twelve percent of consecutive children undergoing bladder outlet surgery for neurogenic incontinence developed clinical parameters leading to augmentation. These occurred most often after BNC.

Long-term fate of the bladder after isolated bladder neck procedure

OBJECTIVE

Recent and historical studies suggest that bladder neck procedures (BNPs) without augmentation are safe and effective. In select patients we have performed BNPs without concomitant augmentation. We sought to determine long-term outcomes of this approach and attempt to identify risk factors for bladder deterioration.

PATIENTS AND METHODS

A retrospective chart review was conducted to identify patients who underwent a BNP without bladder augmentation and followed for at least 4 years. BNPs were only performed in patients with favorable preoperative urodynamics (UDS). The charts were analyzed for long-term outcomes with the primary endpoint of bladder augmentation.

RESULTS

Twenty-nine patients (21 females) with poor bladder outlet resistance underwent a BNP without augmentation (mean follow-up 8 years). Thirteen patients (45%) were augmented at an average of 2.6 years. No predictive UDS parameters were identified; however, exploratory analysis suggested detrusor pressure at 100 mL bladder volume prior to BNP (p = 0.009) was predictive of delayed augmentation.

CONCLUSION

We report a 45% augmentation rate after isolated BNP in patients with favorable preoperative UDS parameters. We recommend close observation of this patient population with serial UDS, routine ultrasounds, and appropriate preoperative counseling prior to undertaking this approach, as this represents a life-long risk to the upper tracts.

Urologic care of the neurogenic bladder in children

Initial care of newborns with spina bifida centers on preventing bladder and upper tract damage from detrusor leak point pressure of greater than 40 cm H(2)O. The authors recommend using urodynamic-based management to select patients with elevated pressures for anticholinergic therapy and intermittent catheterization (CIC), using diapers and observation with biannual renal sonography for the remainder. At the age of toilet training, children who have urodynamic evidence of uninhibited contractions or rising pressure during filling are started on anticholinergics and CIC, or have their dosage increased until pressures less than 40 cm H(2)O and areflexia are achieved. Sphincter incompetency is diagnosed in incontinent children with pressures less than 40 cm H(2)O and areflexia or stress incontinence. Augmentation is indicated in patients with hydronephrosis or reflux and end-filling pressures or DLPP less than 40 cm H(2)O despite medical management to the point of patient tolerance. A minority of patients, not yet well-defined, will also need augmentation after bladder outlet surgery for similar postoperative indications.

Bladder Neck Sling and Appendicovesicostomy Without Augmentation for Neurogenic Incontinence in Children

PURPOSE

Most children undergoing bladder neck sling for neurogenic urinary incontinence also have undergone bladder augmentation. However, complications from enterocystoplasty and uncertainty regarding its indication during bladder outlet enhancement led us to perform slings without augmentation. Herein we report outcomes in consecutive patients.

MATERIALS AND METHODS

A total of 30 patients with neurogenic bladder underwent tight 360-degree fascial sling wrap around the bladder neck and appendicovesicostomy without augmentation. Indications included detrusor leak point pressure less than 50 cm water and stress urinary incontinence. Urodynamics were obtained in all patients preoperatively, in 26 at a mean of 6 months postoperatively and in 16 at a mean of 24 months postoperatively.

RESULTS

Satisfactory continence defined as 2 or fewer damp pads daily was achieved in 83% of patients with followup of 6 to 60 months (mean 22). Symptomatic hyperreflexia and/or loss of compliance developed in 8 patients postoperatively, which responded to anticholinergics in 7. The remaining patient underwent enterocystoplasty 18 months later, for an augmentation rate of 3%. No patient had hydronephrosis or reflux.

CONCLUSIONS

Evaluated parameters, including bladder capacity and compliance determined during preoperative urodynamics, did not predict the need for augmentation. Satisfactory continence can be achieved for neurogenic bladder by sling without enterocystoplasty.

Can urodynamic studies predict bladder behaviour changes after artificial urinary sphincter implantation?

OBJECTIVE

To assess whether preoperative urodynamic studies can predict bladder behaviour changes that will necessitate bladder augmentation in patients with neuropathic incontinence after undergoing artificial urinary sphincter (AUS) implantation.

PATIENTS AND METHODS

We analysed 17 patients, with a mean age of 14.4 years at AUS implantation, who did not undergo bladder augmentation either before or at implantation. All patients were followed at regular intervals before and after implantation. Urodynamic studies were done at least three times before implantation and yearly thereafter. Bladder capacity and compliance were evaluated preoperatively and during the follow up, in order to determine whether these urodynamic measurements could predict the eventual need for bladder augmentation.

RESULTS

After a mean follow up of 7.5 years bladder behaviour was unchanged in 11 patients while six required augmentation. In these six patients, normal bladder capacity and compliance decreased from 67 to 39.6% of age expected capacity (AEC) (P=0.004) and from 31.6 to 13.5 ml/cm of water (P=0.001), respectively. Four of the six had no clinical symptoms to suggest the change in bladder behaviour. The differences in the average preoperative and follow up values for both normal bladder capacity (72.4 vs 83.5% of AEC) and compliance (30 vs 33.7 ml/cm of water) were not significant in the non-augmented patients (P=0.2 and P=0.3, respectively). Preoperative normal bladder capacity and compliance were 72% of AEC and 30 ml/cm of water, respectively, in the 11 non-augmented patients and 67% and 31 ml/cm of water in the six patients with augmentation. These differences between the two groups were not significant (P=0.06; P=0.1).

CONCLUSION

Preoperative urodynamic studies do not predict bladder function outcome after AUS implantation. These patients require long-term careful observation to detect any asymptomatic change in detrusor behaviour.

Experience with non-cycled artificial urinary sphincters

OBJECTIVE

To report our experience in children and adolescents with a non-cycled artificial urinary sphincter. While some children with the AUS can void, others require clean intermittent catheterization (CIC) through the sphincter or an alternative site for catheterization; in some of the latter we have either not cycled (pumped) an activated AUS or the AUS has failed, and there is concern about ischaemia in some adults with a non-cycled AUS.

PATIENTS AND METHODS

In all, 143 patients who had an AUS placed between 1980 and 2002 were reviewed retrospectively; 15 (10 boys and five girls) no longer cycled (pumped) their AUS. The mean age at AUS insertion was 11 years and the mean (range) follow-up after insertion was 10.4 (1.64-22.2) years. The diagnoses included myelomeningocele in 11, sacral agenesis in three and cloaca in one. Nine patients have an activated functioning AUS and in six the AUS does not function; in the first nine the sphincter has not routinely been cycled (pumped) for a mean (range) of 1.6 (0.6-2.9) years. In the other six with a nonfunctioning AUS the mean (range) observation period is 6.4 (1.5-10) years since the system has not functioned.

RESULTS

All patients were completely continent, including the six with a nonfunctioning AUS. After inserting the AUS, two patients voided in combination with CIC (one each urethral and abdominal stoma) and 13 emptied by CIC (nine abdominal stoma, four urethral). There was a mechanical complication in eight patients; three had the AUS repaired and are dry, and five are dry with no repair. In one patient the AUS was never activated. To date there has been no erosion of the cuff in any of the 15 patients with a non-cycled AUS.

CONCLUSION

The AUS remains an extremely reliable procedure to achieve continence in children and young adults. It is versatile and can be combined with other procedures that provide an alternative means for catheterization. While some have noted the need to routinely cycle the AUS to prevent erosion, this has not been our experience in these 15 patients.

The contemporary role of the artificial urinary sphincter

The artificial urinary sphincter has been in use for more than 25 years as a treatment for urinary incontinence due to intrinsic sphincter deficiency. Recent clinical studies have increased our knowledge concerning its use in children and in adult patient populations. Particularly, more long-term data and data on the combination of the artificial urinary sphincter with reconstructive techniques that utilize the bowel have become available. Some interesting new ideas regarding changes in the design of the artificial urinary sphincter have been advanced.

Orthotopic bladder augmentation and substitution

Orthotopic bladder augmentation or substitution using intestinal segments has become a standard procedure for many disorders that cause a loss of functional or anatomical bladder capacity. From the technical point of view, reservoir configuration by detubularizing the intestinal segments is the general practice. Various techniques exist, depending which types of segments and which techniques of ureteral implantation are used. Common problems include urinary incontinence, retention, metabolic disorders, and the possibility of secondary malignancies. As a result, research has been conducted into utilizing tissues other than intestine for bladder augmentation or substitution.