The continent, catheterizable abdominal conduit in adult urological practice

Authors


Basavaraj D.R. Gowda, James Cook University Hospital, Department of Urology, Marton Road, Middlesbrough, Cleveland TS4 3BW, UK.
e-mail: drbasavaraj@hotmail.com, drbasavaraj@btinternet.com

Abstract

OBJECTIVE

To report a large, single-centre experience with a continent, catheterizable abdominal conduit in adult patients.

PATIENTS AND METHODS

We retrospectively reviewed the case notes of all 65 patients who had surgery to create a continent catheterizable conduit based on the Mitrofanoff principle. Operations were carried out over a 13-year period. Data on surgical procedure, complications and final outcome were collected and analysed.

RESULTS

The mean age of the patients was 38.4 years and mean follow-up interval was 75.2 months. Patients with neuropathic lower urinary tracts accounted for the largest single indication for reconstruction (36 patients). The appendix was the conduit of choice and was available and suitable for use in 37 patients. There were 57 patients who continued to use their native bladder or had undergone an augmentation or substitution cystoplasty; 24.5% of these 57 individuals had also undergone closure of the bladder neck or urethra. There were postoperative complications requiring laparotomy in five (8%) patients. In all, 30 patients (46%) had catheterization problems, but most of these were easy to treat. Five patients (8%) had an incontinent conduit which was a more difficult problem to deal with. Two patients have died of unrelated cause and five patients have been converted to an ileal conduit. In all, 58 patients (92%) now have a Mitrofanoff conduit, of which 97% are catheterizable and 95% are continent.

CONCLUSIONS

Continent urinary diversion, based on the Mitrofanoff principle, has similar outcomes in adult urological practice to those described in published paediatric case series. There is good evidence to suggest that Mitrofanoff conduits are durable. However, patients should be aware of complications and the need for long-term follow-up.

INTRODUCTION

The introduction of intermittent self-catheterization in the 1970s revolutionized the subspecialty of reconstructive urology [1]. However, the requirement for a patent, continent urethra that could be catheterized easily and comfortably limited treatment options in a proportion of patients. The search was on for a reliable technique that could produce a continent catheterizable conduit to run from the abdominal wall to the bladder or continent diversion pouch. Numerous techniques were devised and entered the urological literature. Mitrofanoff [2], in a landmark paper, set out the principle of using a narrow conduit with a flap-valve mechanism; operations that utilize these fundamental elements are now frequently termed ‘Mitrofanoff procedures’.

The continent, catheterizable abdominal stoma can be used out of necessity when the urethra is not available (e.g. in a continent urinary diversion after cystectomy or following urethral closure for intractable stress incontinence). However, in other cases the urethra remains patent and continent but cannot be used for self-catheterization because of a patient’s physical constraints (perhaps due to neurological disability) or because catheterization of the urethra is painful or psychologically unacceptable.

More than a quarter of a century has passed since Mitrofanoff’s original paper and it is now possible to evaluate the impact of the continent catheterizable abdominal stoma on urological practice. Although several case series have been published, there are few that provide details of long-term follow-up of a sizeable cohort of adult patients. This paper sets out to provide further data to aid the process of evaluation of the technique.

PATIENTS AND METHODS

With the approval from the hospital audit department, a retrospective review of the results of Mitrofanoff procedures carried out at the Pinderfields Hospital, UK, was undertaken. Case notes were reviewed of all adult patients who underwent construction of a continent catheterizable abdominal stoma, based on the Mitrofanoff principle, between the years 1993 and 2005. Information was gathered about patient demographics, indication for surgery, postoperative complications, and conduit related and unrelated long-term complications. The details of the surgical procedure itself were documented under three headings:

  • 1Conduit – type of conduit and the site of stoma.
  • 2Urinary reservoir – native bladder, augmented bladder or neobladder.
  • 3Bladder neck and urethral procedures – colposuspension, pubo-vaginal or pubo-prostatic sling, artificial urinary sphincter, urethral closure or no procedure.

RESULTS

From 1993 to 2005, 65 patients had surgery to create a continent catheterizable conduit for urinary drainage based on the Mitrofanoff principle. Patient demographics and indication for surgery are shown in Table 1. The mean (median, range) follow-up was 75.2 (78, 2–151) months. Data on the type of conduit, stoma position and reservoir used are provided in Table 1.

Table 1. 
Patient demographics, indications for Mitrofanoff procedure and details of conduit, stoma and reservoir
VariableValue
Total number of patients65
 Male21
 Female44
Mean (range) age, years38.4 (18–70)
Indication for surgery, n
 Neuropathic bladder36
 Urinary retention9
 Interstitial cystitis7
 Undiversion of ileal conduit5
 Idiopathic detrusor overactivity3
 Intractable stress incontinence2
 Radical cystectomy for TCC2
 Anterior exenteration1
Conduit, n
 Appendix37
 Monti procedure19
 Tailored ileum8
 Ureter1
Stoma position, n
 Umbilicus10
 Lower abdomen55
Reservoir, n
 Native bladder12
 Augmented bladder38
 Bladder substitution 7
 Neobladder8

There were 57 patients whose reservoir consisted of their native bladder or an augmented or orthotopically substituted bladder. Of these, 27 did not have stress incontinence and therefore did not have any adjunctive bladder neck or urethral surgery performed. The 30 patients with stress incontinence underwent a range of concomitant procedures. Bladder neck or urethral closure was performed in 14 patients of whom four closures were performed during a procedure subsequent to the original operation when the Mitrofanoff conduit was constructed. Procedures in the remaining 16 patients included: colposuspension (six), sling procedure (five) and insertion of an artificial urinary sphincter (five).

The median (range) postoperative stay was 13 (7–71) days. There were conservatively managed complications in 27 patients that included infections, the need for blood transfusion, prolonged ileus and a minor pouch leak. Major complications requiring early re-operation occurred in five cases. These included an intestinal anastomotic leak in a post-radiotherapy patient, a pouch leak with intestinal obstruction (one), dehiscence of bladder neck closure (one), postoperative haemorrhage (one) and wound dehiscence (one). There were no postoperative deaths.

Long-term complications are grouped as conduit related and conduit unrelated. In all, 30 patients (46%) did not have any conduit-related long-term complications. Sub analysis of the complications that occurred in relation to the Mitrofanoff conduit itself, their management and the current status of patients are shown in Table 2.

Table 2.  Conduit-related long-term complications, management and their outcome
ConduitsAppendixMonti procedureTailored ileumUreterTotal, n (%)
  • *

    Two dead patients excluded,

  • †five patients with ileal conduit excluded.

Total37198165
Recorded complications:
 None1793130 (46)
 Catheterization and stoma 1983030 (46)
 Stomal incontinence1220 5 (8)
Revision procedures used:
 Dilatation of conduit533011 (16)
 Revision of stoma at skin level2873038 (57)
 Full revision of conduit434011 (16)
Current conduit in use*:
 Original conduit32137153 (84)
 Revised new conduit2300 5 (8)
 Conversion to ileal conduit2210 5 (8)
Status of conduit:
 Catheterizable33/3415/167/7156/58 (97)*
 Continent34/3415/165/7155/58 (95)*

Several long-term complications have arisen in this cohort of patients that are not specifically related to the Mitrofanoff conduit itself. In the follow-up period, several patients have had further surgery to deal with such problems. Indications for additional operations include: bladder calculus (five), breakdown of bladder neck closure (two), incontinence (one), intestinal obstruction (one), osteitis pubis (one), urethral pain (one) and vesicovaginal fistula (one). Two patients with recurrent UTIs needing frequent inpatient treatment have now been converted to ileal conduit urinary diversion.

Two patients have died; one from lymphoma and the other from sepsis due to an infected pressure sore. At present 56 patients are using their continent catheterizable conduit, two patients are performing intermittent self-catheterization via the urethra and five patients have an ileal conduit.

DISCUSSION

The basic components of the Mitrofanoff principle as summarized by Duckett and Snyder [3] are:

  • 1Use of a narrow supple conduit brought to the skin as a catheterizable stoma.
  • 2An antirefluxing connection of this conduit to a reservoir to provide continence (flap-valve mechanism).
  • 3A large, low pressure urine storage reservoir.
  • 4Creation of an antireflux connection of the upper urinary tract to the reservoir.
  • 5Intermittent catheterization to produce regular complete emptying of the reservoir.

The flap-valve mechanism relies on any pressure elevation within the reservoir being transmitted effectively to a supple, small-diameter conduit in a submucosal location, thereby compressing its lumen against the firmer wall of the storage reservoir. The tunnelled appendix of the Mitrofanoff procedure has been shown to have a significantly higher resting pressure than that found in valve mechanisms that use different principles such as intussusception; the pressure in the appendicial lumen can increase to nearly three-fold that in the reservoir itself [4].

Several published case series have reported on the use of urinary reconstructions based on the Mitrofanoff principle. Several of these series describe >50 patients [5–15]. However, there is less data available on long-term results with details of follow up over a period of >5 years [12,16–18]. Gerharz et al. [19] have published their results of using submucosally embedded appendix in a continent cutaneous diversion in the Mainz I pouch in 118 patients with a mean follow-up of 60 months. The indication for this surgery in 98 of the 118 patients was pelvic malignancy; this contrasts with the benign bladder disease or bladder dysfunction that are included in most of the published series detailed above. A series from Kaefer et al. [12] is the only published series of >50 patients (mean age of 13.7 years) with an average follow-up of >5 years. The present series provides this depth and length of experience in an adult population.

After the introduction of the continent catheterizable abdominal conduit into urological practice, there has been a steady increase in the range of indications for such a procedure. The commonest indication in many series, including the present one, is a neuropathic lower urinary tract. Other indications include congenital abnormalities such as the epispadias/extrophy complex, cloacal anomalies and posterior urethral valves [9,11,20], inflammatory conditions including interstitial cystitis [21], neoplastic conditions requiring cystectomy or pelvic exenteration [19,21], post-traumatic conditions such as urethral stricture [22], urinary retention [23], vesicovaginal fistula [24] and intractable incontinence [25]. It is therefore apparent that the Mitrofanoff procedure has provided patients with a further set of possibilities when they are confronted with options for urinary tract management that might otherwise have been limited to long-term catheterization or ileal conduit diversion.

When available and healthy, the appendix is our preferred conduit of choice. In most cases we have taken a rectangular cuff of caecum in continuity with the appendix, which is then tubularized in order effectively to lengthen the appendix and ensure adequate conduit length. Others have also described the use of caecum to lengthen the conduit [26]. In the absence of appendix, we have stopped using tailored ileum as a conduit in favour of reconfigured, transversely retubularized intestinal segment as described by Monti et al. [27]. In adult practice it is nearly always the case that two adjacent ileal segments are needed (the double Monti) in order to create a conduit of adequate length that can be tunnelled into the posterior wall of the bladder and reach the anterior abdominal wall without undue tension.

It has been our practice to try to maintain urethral patency whenever possible. The advantages to the patient of a competent urethra include access for catheterization in the event of conduit problems and the availability of easy endoscopic access should complications such as stones develop within the bladder. We have used colposuspension, sling procedures and the artificial urinary sphincter in selected patients to maintain continence and avoid closure of urethra or bladder neck. However, bladder neck or urethral closure was necessary in 14 patients (24.5%). Other published series have reported a bladder neck/urethral closure rate of 5%[15], 17%[7], 50%[12] and 91%[17], suggesting that differing approaches are taken in different units; this will depend on the patient population being managed and the philosophy of the surgical teams. Our experience of dealing with problems such as stones within a reservoir and acute conduit catheterization difficulties where reservoir access is solely provided by the continent catheterizable conduit has reinforced our view that bladder neck or urethral closure should represent a last resort.

The combined clinical experience that is represented by the present and other published series shows that the Mitrofanoff operation can achieve satisfactory long-term outcomes for such factors as ability to catheterize the conduit and conduit continence. However, it is important to establish whether these outcomes can be achieved with acceptable complication and re-operation rates.

Most of the present patients were undergoing reconstructive surgery of which the creation of a Mitrofanoff conduit was only one component. The early complication rate reflects the complex nature of such undertakings. Five patients underwent early re-operation to treat postoperative complications. There were also several conduit unrelated long-term complications, which again reflected the nature of the reconstructive procedures. Stone formation in the urinary reservoir was the most common conduit unrelated long-term complication requiring surgical intervention affecting five cases in the present series, all in augmented bladders. All cases were managed successfully by cystolithotomy. Kaefer et al. [12] in their series of 50 patients with Mitrofanoff conduits have reported a 12% incidence of stone formation and they advocated cystolithotomy in view of the generally large stones that were seen and concern that stone fragments may lodge in the interstices of the bowel segment and serve as a nidus for recurrent stone formation. An alternative approach was adopted by Cain et al. [28] who reported successful percutaneous management in 12 of 13 paediatric augmented bladders. It seems likely that there will be a move towards less invasive approaches to the problem of stone formation within a bladder or reservoir with limited access but, at the present time, our approach is to undertake the open removal of large stones in these circumstances.

Details of conduit-related long-term complications and their management are given in Table 3. These data provide an indication that stomal incontinence may occur more commonly when a Monti ileal conduit is used as opposed to appendix. Other series provide differing outcomes when considering the possibility that a Monti conduit may work less reliably than an appendiceal one; increased catheterization difficulties were seen by Narayanaswamy et al.[9], while other authors have not seen differences in outcomes [15,16]. Available evidence would therefore suggest that while both ileum and the appendix can be successfully used to create a Mitrofanoff conduit, the latter should be considered as a first choice as long as the appendix is of adequate length and shows no suggestion of fibrosis or stricturing.

Table 3.  Conduit-related complications in published series with a minimum mean follow-up of 48 months
ReferenceMean age, yearsNumber of conduitsMean follow-up, monthsCatheterization/ stoma problems, n (%)Incontinence, n (%)
Barqawi et al.[5]8.6984821 (21)4 (4)
Harris et al.[10]13.1505112 (24)1 (2)
Kaefer et al.[12]13.7506210 (20)9 (18)
Lemelle et al.[16]14.2416417 (42)2 (5)
Fishwick et al.[18]12.2101204 (40)0
Liard et al.[17]8.3232409 (39)5 (22)
Present series38.4677330 (45)5 (7)

Two patients have died of unrelated cause and five have had their conduits removed during conversion to ileal conduit diversion. Indications for abandoning their continent catheterizable conduit comprised recurrent UTIs in two and inability to comply with regular intermittent self-catheterization, recurrent difficulty with catheterization and urethral incontinence in one patient each.

The present series includes 58 patients who have Mitrofanoff conduits in situ. In all, 56 of these 58 patients continue to catheterize their conduits while two patients have switched over to urethral intermittent catheterization. Of these two, one has opted to have his stenosed conduit revised, whilst other has favoured urethral intermittent catheterization. Five patients have had significant problems with stomal incontinence of whom two are dry after further treatment to correct detrusor overactivity (one after bladder augmentation and the other with anticholinergic medication). We have occasionally used injectable bulking agents in an attempt to treat stomal incontinence with variable results. Guys et al. [29] have reported good short-term outcomes using injectable agents in this context.

The reporting of conduit-related complications in different case series is somewhat variable. Table 3 tabulates results from series with a minimum mean follow-up of 4 years [5,10,12,16–18]. The prevalence of catheterization and stomal problems increase with the length of follow-up; this matches our own experience. However, a common theme that emerges from most series is that, although the conduit-related complications are common, most of them can be managed by simple surgical intervention [7]. To deal with catheterization and stoma problems in the present series, 11 stomal dilatations and 38 skin level stomal surgical corrections were performed. Most of these procedures were carried out in the day-case setting. Of the 11 conduits needing exploration, five needed revision of the whole conduit and were managed by the creation of a new Monti conduit.

The present series includes patients with various different indications for reconstructive surgery. The incidence of complications suggests that there may be different success rates for this type of reconstructive surgery amongst differing patient groups. Of the 35 alive patients with neuropathic lower urinary tract dysfunction, all but one patient has the original conduit, with one patient unable to catheterize the conduit and one with stomal incontinence, whereas the subgroup of eight patients presenting with urinary retention have had inferior outcomes with one patient having undergone a revision of the conduit and three now with ileal conduit diversions. While we would not take the extreme view that such surgery should not be undertaken in those with non-neurogenic urinary tract dysfunction, it has to be accepted that complication rates tend to be higher in patients where there may be psychosocial influences involved in conjunction with urinary problems. There is undoubtedly a need to refine the process of selecting patients for reconstructive surgery and to provide psychological support to patients for whom their lower urinary tract reconstruction represents a continuing source of anxiety and difficulty.

In conclusion, the principles set out by Mitrofanoff have enabled the development of the continent, catheterizable abdominal conduit. Such conduits have provided new options for lower urinary tract management in patients for whom urethral self-catheterization is either impossible or unacceptable. In our practice, the option of creating a Mitrofanoff conduit is routinely offered to patients undergoing reconstructive surgery who will require intermittent self-catheterization postoperatively. There is now a significant body of evidence within case series to suggest that the use of such conduits is reasonable in light of their general durability. However, patients must be aware of the possibility of postoperative difficulties that may require further surgical procedures to deal with problems such as catheterization difficulties or stomal incontinence. There is a need to continue to collect data on the long-term results of these procedures, as large case series with long-term follow-up remain few.

CONFLICT OF INTEREST

None declared.

Ancillary