1488

PART VIII

GENITOURINARY DISORDERS

resolve, or the degree of ureteral dilation may improve

Complications of cutaneous vesicostomy include stomal

enough that ureteral tapering is not required at the time of

stenosis, prolapse, peristomal dermatitis, and bladder calculi.

reimplantation.^3-4

Although bacterial colonization of the

Stomal stenosis is more common with a stiff or thick bladder

open system is common, symptomatic infections and urosepsis

wall as in posterior urethral valves. Failure to fashion the vesi-

are reduced. One concern about prolonged vesicostomy

costomy from the dome of the bladder may allow the posterior

drainage in the non-neuropathic population is failure of

bladder wall to prolapse through the vesicostomy. This is one

the bladder to develop normally in the absence of cyclic

advantage of the Blocksom technique over the Lapides vesi-

filling and emptying.^10-11 Several studies have refuted this

costomy. Prolapse is managed by manual reduction with tem-

concern.^4,12-13

porary catheter drainage and revision of the low vesicostomy.

Once the urinary tract is stabilized and the long-term po-

Dermatitis is particularly bothersome in some patients and is

tential of the bladder becomes clearer, the vesicostomy is eas-

managed with application of a zinc oxide barrier cream or top-

ily closed. It may be closed primarily or in combination with

ical treatment for obvious candidiasis. Bladder calculi are un-

continent diversion. Some patients and families are not appro-

usual provided that the vesicostomy is functioning well and

priate candidates for vesicostomy closure or find that vesicos-

the upper tracts are drained.

tomy and diaper drainage is an acceptable low-maintenance

permanent option. Vesicostomy, with or without the use of

CUTANEOUS URETEROSTOMY

an ostomy appliance, can also be performed in adult patients

who are not candidates for continent diversion.⁹

Ureterostomy for temporary supravesical urinary diversion is

Two techniques for cutaneous vesicostomy have been used

rarely performed today. It has been used historically for drain-

for many years. Lapides described elevation of an anterior blad-

age of a profoundly dilated upper urinary tract in the face of

der wall flap with deep insertion of an abdominal skin flap to

urosepsis¹⁷ or to maximize drainage of the renal units in cases

fashion the cutaneous vesicostomy.¹⁴ The more common tech-

of severe obstruction. Percutaneous or endourologic drainage

nique was described by Blocksom in 1957¹⁵ and modified by

of these systems is possible now in children, but tube size

Duckett (Fig. 118-1).¹⁶ The Blocksom vesicostomy is fashioned

limits the utility of this in very small infants.¹⁸ Low diversion

through a small transverse incision halfway between the umbi-

can be performed as a loop or end cutaneous ureterostomy

licus and the pubis. The fascia is incised, and the peritoneum is

(Figs. 118-2 and 118-3), and subsequent takedown involves

pushed superiorly off the dome of the bladder. The urachal

ureteroneocystostomy. The diversion allows the caliber of

remnant is divided, and the dome of the bladder is pulled

the ureter to decrease, thereby reducing the complexity of

up to the skin. The fascia is secured to the bladder wall to form

the reimplantation. Diversion at the level of the kidney is per-

a 24-Fr defect, and the bladder is matured as a flush stoma.

formed through a flank incision and can be performed as a

FIGURE 118-1

The Blocksom vesicostomy, showing the incision in the

FIGURE 118-2

The loop ureterostomy is easily taken down and there-

dome of the bladder, the fixation to the overlying fascia, and the everted

fore allows for an excellent temporary diversion.

stoma.

CHAPTER 118

INCONTINENT AND CONTINENT URINARY DIVERSION

1489

Another method to treat distal ureteral obstruction is cre-

ation of a freely refluxing end-to-side or side-to-side ureteral

reimplant.²³ This alternative approach, while obviating the

continual drainage of urine via a cutaneous stoma, remains

controversial.

CUTANEOUS PYELOSTOMY

As with cutaneous ureterostomy, proximal diversion by pye-

lostomy has limited indications in current practice. The con-

troversies surrounding this type of diversion are similar. With

direct drainage of the renal pelvis, pyelostomy may be used for

temporary diversion in select cases of obstruction at the ure-

teropelvic junction but could also be used as discussed earlier

for posterior urethral valves. Pyelostomy requires a dilated

extrarenal pelvis to create a tension-free anastomosis to the

skin. Takedown of the pyelostomy at the time of a definitive

procedure is relatively simple due to reliable blood supply

to the renal pelvis.

ILEAL CONDUIT/COLON CONDUIT

Permanent supravesical urinary diversion was popular many

decades ago as reliable means to manage neuropathic bladder,

bladder outlet obstruction, and severe urinary incontinence.

Conduit diversions have been created with most intestinal

segments, although the ileum (Fig. 118-4) and colon are used

FIGURE 118-3

The end ureterostomy requires formal reimplantation to

most commonly. Both simple refluxing and tunneled nonre-

reverse.

fluxing ureterointestinal anastomoses have been used. The

primary advantage of the colon conduit over an ileal conduit

loop ureterostomy, Sober ureterostomy, or end ureterostomy.

is the reliable antireflux reimplantation achievable with colon.

A loop ureterostomy can easily be taken down and is the more

The risk of upper tract deterioration after ileal conduit di-

appropriate choice for temporary diversion. End ureterostomy

version has exceeded 50% in some series.^24-26 Although this

just below the ureteropelvic junction makes reconstitution of

is not a tremendous concern in the older patient after cystec-

the ureter more difficult and should be reserved as a rare per-

tomy for bladder carcinoma, the long-term impact on the kid-

manent form of diversion in cases of severe bladder dysfunc-

neys is extremely relevant in the pediatric population. The

tion.¹⁸ Sober ureterostomy, with its proximal diverting limb

ability to create a nonrefluxing anastomosis between the ureter

and reanastomosis of the distal limb to the renal pelvis, is rarely

used today and is technically much more involved and may

therefore be less appropriate for diversion during acute illness.

On the other hand, it offers the advantage of diversion and

continued antegrade drainage to cycle the bladder.¹⁹ In all

cases, care should be taken to preserve the medial blood sup-

ply and adventitial vessels and to create a tension-free anasto-

mosis to the skin. Given the profoundly dilated nature of the

ureter in most of these cases, stomal stenosis is rarely an issue.

Supravesical diversion may be warranted in select posterior

urethral valve patients when renal function fails to improve af-

ter bladder drainage.¹⁹ Persistent ureterovesical junction ob-

struction is the concern. Ureterostomy and pyelostomy

would maximize upper tract drainage, but percutaneous

nephrostomy is a less invasive temporary means to assess the

potential of the affected kidney.²⁰ Patients who demonstrate

improvement in renal function after supravesical diversion

may do so because of better drainage or just due to normal renal

maturation.²¹ As with cutaneous vesicostomy, there is concern

that the valve bladder will fail to develop normally if the urine is

diverted. In patients with a solitary functioning kidney, a loop

ureterostomy or an end ureterostomy would defunctionalize

the bladder. Several studies suggest that bladder dysfunction

is due to bladder wall abnormalities from infravesical obstruc-

FIGURE 118-4

The ileal conduit is the standard permanent supravesical

tion rather than supravesical diversion of urine.^13,22

diversion for patients whose bladder is absent.

1490

PART VIII

GENITOURINARY DISORDERS

and colon gives colon conduits a theoretical advantage over

other efforts to manage the bladder pressures and urinary in-

ileal conduits. Unfortunately, deterioration of the upper tracts

continence and refused or were not candidates for continent

occurs in 26% to 48% of cases and ureteral reflux persists in

diversion. Many suffered severe complications from use of a

8% to 58% of colon conduits.²⁷

Anastomotic stricture

chronic indwelling urethral catheter. Several series report ex-

occurs with similar frequency with ileum and colon (9%

cellent results with regard to preservation of renal function,

to 22%).^24,27

incidence of urinary tract infection and urolithiasis, and sto-

Koch and colleagues²⁴ compared a cohort of myelomenin-

mal complications.^32-35 The ileovesicostomy functions as a

gocele patients with ileal conduit diversion to another group

pop-off valve to maintain safe bladder storage pressures. Sto-

managed with CIC. The ileal conduit group suffered renal de-

mal leak-point pressures are low, and a moderate residual

terioration, nephrolithiasis, and pyelonephritis significantly

urine remains.³⁵

more than the catheterization group. Bone density was de-

Incontinent ileovesicostomy is an option to consider in

creased in both groups and the incidence of fractures was

select pediatric patients with limited dexterity and social

equal, but the diversion group had impaired linear growth,

support. Although it does require a permanent stoma, pres-

more spinal curvature, and more complications from orthope-

ervation of renal function appears superior when compared

dic procedures. The metabolic alterations associated with in-

with standard conduit diversion. In addition, the disruption

corporation of intestinal segments into the urinary tract do

of the ureterovesical junction is not required. Parents may

occur with incontinent diversions.²⁴

have difficulty accepting permanent diversion even if the

Other complications of conduit diversion included stomal

child has limited potential to perform self-catheterization

stenosis, stomal prolapse, peristomal hernia, and peristomal

in the future. Some families are not ready to assume the care

dermatitis. Stomal stenosis occurred in 8% to 61% of cases.

required for bladder augmentation or continent urinary

Stoma complications are best prevented with careful surgical

reservoir, despite the fact that the child needs reconstruction

technique including preservation of intestinal perfusion, cre-

to preserve the upper urinary tracts. In these instances,

ation of a straight and adequate caliber fascial window, and fix-

incontinent ileovesicostomy with both an efferent inconti-

ation of the conduit to the fascia. A protuberant rosebud stoma

nent limb and a large open patch of ileum to augment the

enhances the fit of the stoma appliance and prevents stenosis.

bladder can be considered. Consideration could be given

Bacteriuria is nearly universal but does not cause upper

to creation of a Mitrofanoff catheterizable channel at the time

tract damage if the ureterointestinal anastomosis and the con-

of the initial procedure. Should the family later embrace

duit itself function appropriately.^27-28

Stasis of colonized

continence and the long-term care of bladder augmentation,

urine, however, may contribute to upper tract stone formation

the ileal chimney can be amputated to leave a continent

and may have other implications as well. Nitrosamines pro-

diversion.³⁶

duced by the mixture of urine and bacteria appear to have

Thorough preoperative bowel preparation and sterilization

some role in induction of malignancy in the isolated intestinal

of the urine are required. A stoma site is carefully preplanned

segment.^27,29

for the right lower quadrant to ensure optimal fit of the stoma

Austen recently reviewed the world literature and identi-

appliance. The bladder is bivalved in the coronal plane in

fied 81 tumors collectively in a variety of continent and incon-

preparation for anastomosis to the isolated ileal segment.

tinent diversions with incorporated bowel segments. This

The proximal end of the ileum is opened widely on its antime-

total is exclusive of the large number of malignancies reported

senteric border and anastomosed to the bladder in a running

after ureterosigmoidostomy. Neoplasia was reported in 12 ileal

fashion. The length of the ileal segment can be tailored to ac-

conduits and 5 colon conduits with a mean latency of 22 and

count for body habitus and for the need to augment the native

10 years, respectively. Colon conduit tumors were exclusively

bladder capacity.³² A rosebud stoma is fashioned in the right

adenocarcinoma, but transitional cell carcinoma, squamous

lower quadrant, and a 22-Fr catheter is left in place for 3

cell carcinoma, and carcinoid and anaplastic tumors were also

weeks to maintain the caliber of the ileovesical anastomosis.

found in ileal conduits. Chronic inflammation of the intestinal

If significant augmentation is performed, a suprapubic

segment may play a role in the malignant changes. Early yearly

catheter should be left as well to maximize perioperative

surveillance for tumor is recommended.³⁰

drainage. In select patients with perineal excoriation from

Preoperative preparation for conduit diversion involves a

urinary incontinence, a bladder neck or urethral procedure

full mechanical and antibiotic bowel preparation and paren-

in conjunction with an ileovesicostomy may be used to create

teral antibiotic to sterilize the urine on the day before surgery.

outlet resistance.

Patients with severe neuropathic bowel may actually require

more than one day of preparation for adequate cleanout. It

is critical that an enterostomal therapist mark potential stoma

sites bilaterally after examining the patient in multiple posi-

Continent Urinary Diversion

------------------------------------------------------------------------------------------------------------------------------------------------

tions. The abdominal contour can change significantly in mye-

lomeningocele patients when seated, and an ill-fitting ostomy

Many different types of continent urinary diversions have

appliance will be a lasting source of dissatisfaction.

been developed to improve or replace the native lower urinary

tract. The chosen technique depends largely on the surgeon’s

experience and preference, but the primary pathology plays a

INCONTINENT ILEOVESICOSTOMY

large role in any given patient. Reconstruction is tailored to the

Incontinent ileovesicostomy, initially described by McGuire

specific anatomy and related functional deficits. A fundamen-

and colleagues in 1994,³¹ has primarily been used in the adult

tal difference exists in pediatric lower urinary tract reconstruc-

population with bladder and sphincter dysfunction secondary

tion versus that of adults. In adult reconstruction, a particular

to spinal cord injury and multiple sclerosis. Patients had failed

type of reconstruction (i.e., Kock pouch, Indiana pouch) may

CHAPTER 118

INCONTINENT AND CONTINENT URINARY DIVERSION

1491

be chosen preoperatively. In children, the principles of a low-

The vast majority of augmentations are performed with

pressure reservoir with a means of catheterization without

gastrointestinal segments because bowel segments are readily

leakage or reflux must be achieved from the tissues available

available and easily configured. Ileum is currently the most

at this time of reconstruction. Whenever possible, enhance-

popular segment,^41-43 but sigmoid is often used. Stomach

ment of the native bladder and outlet is preferred to avoid

and ileocecal segments have been used but have only a small

the potential complication associated with ureteral anastomo-

role in contemporary management.^44-47 Their abundance en-

sis to a CUR. CUR would be performed if the native bladder is

sures that adequate capacity is obtained while detubulariza-

absent or not salvageable. Patients with bladder agenesis syn-

tion and the natural viscoelastic properties allow for the

dromes, the most severe bladder exstrophy, and pelvic organ

low-pressure reservoir.^48-49 However, the secretive^50-51 and

destruction secondary to trauma or malignancy would be

absorptive⁵² nature of this tissue is also responsible for most

candidates for CUR.

of the common complications associated with this procedure.

Continent urinary diversion is now common, but one must

Requirements for a successful augmentation include proper

remember that it requires a broad spectrum of surgical skills

patient selection,⁵³

the ability and willingness to perform

and must address the varied underlying diagnoses. By defini-

CIC,^50,54

proper selection of augmentation material, and

tion, a reservoir that must be emptied by intermittent catheter-

recognition and treatment of complications.

ization is created. This may include the augmentation of an

intact but severely diseased bladder or the creation of a reser-

voir completely from heterologous tissue. The surgical goals

PATIENT EVALUATION AND SELECTION

and principles are similar: to create the ideal storage reservoir

for urine that can be easily emptied with the minimum of com-

The patient, family, and entire health care team must be in-

plications. Because the gastrointestinal (GI) tract is plentiful

volved in the decision to pursue major surgery. The common

and accessible, it is the most common source of tissue. The

risks of incorporating GI segments into the urinary tract in-

physiologic variability along the GI tract allows the surgeon

clude mucus production, urinary tract infection, bladder

to tailor the reconstruction to the patient. However,

and renal calculi, and metabolic changes. Life-threatening

these complex surgeries are not without complications, and

risks such as malignant degeneration and spontaneous perfo-

these have to be understood and anticipated.

ration must be explained to the family and child, and they

must be understood.^50,51,54 Everyone involved in caring for

the child must be committed to the appropriate postoperative

care including mandatory use of CIC and regular bladder

BLADDER AUGMENTATION

irrigation.^50,54,55

Bladder augmentation is an essential component of the pedi-

Clinical evaluation requires a thorough history and physi-

atric urologist’s surgical armamentarium. It has a prominent

cal examination. Particular attention should be paid to latex

role in the management of many lower urinary tract (LUT) dis-

allergy because this can be a fatal complication. Preoperative

orders including neurogenic bladder, posterior urethral

evaluation should include a renal-bladder ultrasound (RBUS)

valves, and bladder exstrophy. The modern application often

and a voiding cystourethrogram (VCUG). Serum chemistries

includes the use of a continent catheterizable abdominal wall

are required because impaired renal function may change

stoma based on the Mitrofanoff principle. This is generally

the gastrointestinal segment used.⁵⁴ Initially, it was suggested

performed using either the appendix (appendicovesicostomy)

that a creatinine clearance of less than 60 mL/minute might be

or reconfigured ileum (Monti) and may require an additional

a contraindication for the use of ileum as a continent urinary

procedure to improve the continence mechanism at the blad-

reservoir,^56-57 but augmentation often stabilizes renal func-

der neck. Intermittent emptying via the native urethra remains

tion and reconstruction has been done before renal transplan-

an option.

tation. Urodynamic studies are necessary to determine outlet

As previously discussed, children with severe LUT dys-

resistance, bladder capacity, and storage pressures. Cystos-

function were historically treated with urinary diversion.

copy will confirm anatomy and ensure that no untoward

Lapides’ introduction of clean intermittent catheterization en-

findings that may hinder reconstruction are present.⁵⁰

sured that any child could safely empty his or her bladder.^1,37

The net result of these investigations is a comprehensive

This brought the dawning of lower urinary tract reconstruc-

surgical plan. The exact procedure will depend on which seg-

tion and allowed the urinary tract to remain intact and avoid

ment is to be used and whether the patient requires concom-

the use of external collecting devices. Advances in urodynamic

itant ureteric reimplantation, bladder neck procedure, and a

monitoring improved our ability to predict who would best

catheterizable channel. Patients with a neurogenic bladder

benefit from bladder reconstruction and therefore prevent re-

may also undergo an antegrade continence procedure to assist

nal deterioration.² Parallel medical advances ensured the sur-

evacuation of their neurogenic bowel.⁵⁸

vival of these complex patients and allowed for the shift of

Preoperative preparation usually involves bowel prepara-

focus toward continence as an important aspect of their

tion, as described previously for conduit diversion. Perioper-

quality of life.^38-39 Recent advances with cutaneous catheter-

ative antibiotics and a sterile urine are required and are

izable channels continue to simplify care and increase its

particularly important if the patient has a ventriculoperitoneal

popularity.⁴⁰

shunt.⁵⁹

The primary goal of lower urinary tract reconstruction is to

Long-term follow-up is required with all patients. After the

store urine safely without leakage. Adequate storage requires a

postoperative visit, and assuming the absence of complica-

low-pressure, highly compliant reservoir of adequate volume,

tions, the patient should be seen annually with a history, phys-

whereas continence results from limited contractility and an

ical examination, creatinine and electrolytes, an ultrasound,

effective sphincter mechanism.

and an annual cystoscopy 5 to 10 years out from surgery.^50,54

1492

PART VIII

GENITOURINARY DISORDERS

GASTROINTESTINAL CYSTOPLASTY

ILEOCYSTOPLASTY

Most children undergoing lower urinary tract reconstruction

Ileum has become the segment of choice due to its inherently

for hostile bladder dynamics can have their native bladder

low contractility, abundance, and ease of manipulation.^41-43

preserved but need to have it augmented to lower intravesical

In children 20 to 30 cm are harvested, with the distal margin

pressures, limit contractility, and improve compliance. Gas-

located 15 to 20 cm from the ileocecal valve to prevent vitamin

trointestinal segments are generally used, but this requires

B₁₂

and bile salt malabsorption.^49,64

Ileum is known to

reconfiguration and detubularization to prevent their own

produce less mucus than colon, and we noted a lower rate

inherent contractile properties.^44,48,49,60

Maximum storage

of perforation when compared with sigmoid.³⁵ It has the dis-

capacity requires approximation of the spherical shape.⁴⁸

tinct disadvantage of being difficult to create submucosal

A widely bivalved bladder enables this and helps to prevent

tunnels for ureteral reimplantation or catheterizable channel

the augment behaving as a diverticulum (Fig. 118-5). The

placement.

volume of the sphere is maximized by folding the ileum into

a U or an S shape, which increases the potential radius and

SIGMOID CYSTOPLASTY

volume (Fig. 118-6).⁵⁴ This reconfiguration, as well as detu-

bularization along the antimesenteric border, is critical to dis-

Advantages of the sigmoid include its proximity to the bladder

rupting intestinal contractions because the intact intestine

and its marked dilation in the neuropathic population. Ap-

can create pressures of 40 to 100 cm H₂O.^61-63 The recon-

proximately 15 to 20 cm are isolated and irrigated with an an-

structive surgeon should err on the side of a larger rather

tibiotic solution. Due to the extreme contractile nature of the

than smaller augmentation.⁵⁰ Regardless of the bowel seg-

sigmoid, complete detubularization is essential.⁴⁶ Spontane-

ment selected, a water-tight anastomosis using absorbable su-

ous perforation rates have been shown to be higher with sig-

ture is done. A suprapubic tube is placed into the native

moid as opposed to ileal augmentations,⁶⁵ presumably due to

bladder and secured to the abdominal wall, and a perivesical

their increased contractile pressure.⁶⁶

drain is placed.

ILEOCECAL CYSTOPLASTY

The main advantage of the ileocecal segment is the consistent

blood supply. Two main techniques exist, each with multiple

variations. Either both the ileal and cecal segment are

tabularized and reconfigured together, or solely the cecum

is tubularized and the ileum used to create a continent stoma⁴⁷

or for ureteric replacement.⁵⁴ This segment is infrequently

used in the neuropathic population because loss of the ileo-

cecal valve can result in intractable diarrhea.⁶⁷

GASTROCYSTOPLASTY

The stomach is much less absorptive than other intestinal seg-

ments, and its secretion of hydrogen ions may be beneficial in

patients with chronic renal failure and metabolic acidosis.^44,68

A 10- to 15-cm wedge from the greater curvature is mobilized

FIGURE 118-5

The offset cystoplasty allows for more mobility of the

along the right gastroepiploic vessel and passed through the

detrusor muscle and provides better access to the muscular backing that

mesentery of the transverse colon to the bladder. Originally

is essential for implantation of the catheterizable channel.

felt to be an option for all augmentation candidates, its role

is now limited primarily due to the hematuria dysuria

syndrome, which occurs in up to 70% of patients.

Autoaugmentation

------------------------------------------------------------------------------------------------------------------------------------------------

Described by Cartwright and Snow,⁶⁹ in order to decrease

intravesical pressures and increase bladder capacity, a large

diverticulum is created at the dome of the bladder by a detrusor-

ectomy while leaving the bladder mucosa intact. Unfortunately,

although the initial reports of urodynamic improvements

seemed promising, the results were not as durable as those

patients treated with an enterocystoplasty and seem to do better

in adults than in children.^70-72 In general, autoaugmentation

will decrease intravesical pressures. It will not reliably increase

FIGURE 118-6

The ideal bladder augmentation will increase both capac-

ity and compliance, which are required for continence and renal

capacity that is often necessary in children. It does remain an

protection.

option for a select group of patients.

CHAPTER 118

INCONTINENT AND CONTINENT URINARY DIVERSION

1493

SEROMUSCULAR SEGMENTS (WITH

UROTHELIAL LINING)

To avoid the incorporation of intestinal mucosa with the uri-

nary tract, Shoemaker and Marcucci described using seromus-

cular segments of bowel overlying an autoaugmented

bladder.⁷³ Most experiences have demonstrated that whether

the segment is facing the bladder lumen or is reversed, signif-

icant contracture develops.^74-75

Most recently, some have

demonstrated success with demucosalized colon over urothe-

lium with findings of increased bladder capacity and low fill-

ing pressures.⁷⁶ Long-term results and more experience are

necessary to help determine the efficacy of this approach.

CONTINENT CATHETERIZABLE CHANNELS

Bladder augmentation and bladder neck surgery markedly de-

crease the patient’s ability to empty spontaneously while in-

creasing the consequences of incomplete emptying. Not

adhering to a strict CIC schedule can result in an increased

risk of urinary tract infection, bladder stones,⁷⁷ and spontane-

ous bladder perforation.^78-79 In 1980 Mitrofanoff introduced

the principle of a continent channel by using the vermiform

appendix and implanting it submucosally into the bladder.⁸⁰

What is now known as the “Mitrofanoff Principle” states

that any supple tube implanted submucosally with sufficient

muscle backing acts as a flap valve and results in a reliable

continence mechanism (Fig. 118-7).

The Mitrofanoff principle has been widely embraced and ap-

plied to a variety of tissues because the appendix (Fig. 118-8) is

not always appropriate or available, especially if a simultaneous

Malone antegrade continence enema (MACE) procedure is be-

ing performed. The use of stomach, colon, bladder, ureters,

and fallopian tubes have all been reported with good suc-

FIGURE 118-8

A, The appendix is readily accessible and mobilized with

maintenance of its vasculature. B, It is implanted easily beneath the blad-

cess.^81-92 However, the utility of the tubularized ileal channel

der mucosa to provide a reliable catheterizable channel.

was introduced by Yang⁸⁷ and Monti⁸² and has assumed a lead-

ing role in genitourinary reconstruction (Fig. 118-9).^84,93

The continent catheterizable channel requires a supple

Monti-Yang technique requires the isolation of 2 cm of ileum,

tube, straight path, and short intra-abdominal segment. The

opening it along its antimesenteric border and retubularizing

appendicovesicostomy requires full mobilization of the right

it over a 12-Fr catheter. The channel is then preferentially

colon to ensure adequate mobility. Amputation should in-

implanted into the submucosa of the bladder because its thick

clude some cecum because this allows for a larger-caliber cu-

muscle is ideal for a continent valve; however, stomach and

taneous stoma or can be tubularized to increase stomal

the tenia coli have been successfully used. Reimplantation into

length.^81,94 The appendix is then carefully mobilized with

ileum is the most challenging and requires the creation of a

the mesoappendix to ensure adequate blood supply. The

seromuscular trough. The stoma site can be hidden within

the umbilicus or placed in the right lower quadrant, the latter

being favored as a shorter and more direct route. Great care is

taken to ensure a catheter, usually 12-Fr, passes easily and that

the channel is as straight and tension free as possible. When

satisfied, the surgeon fixes the channel to the abdominal wall

with a permanent suture. Many ingenious skin flap techniques

are used to minimize the chance of stomal stenosis, all insert-

ing into the spatulated channel. An indwelling catheter is

left for 2 to 3 weeks, and the first catheterization is usually

performed in the clinic setting.

Stomal continence is excellent, and rates of 90% to 99% are

reported in the two largest published series.^84,95 Complica-

tions pertain primarily to difficulties with catheterization,

most commonly at the skin level, but may also occur deeper

within the channel itself. Stomal stenosis is reported to occur

FIGURE 118-7

The Mitrofanoff principle states that a supple tube will

in 5% to 25%,^95-96 with a lower rate potentially seen with

compress with increasing intravesical pressure and provide continence.

tubularized ileum.⁸⁴

1494

PART VIII

GENITOURINARY DISORDERS

replacement. When required, however, it allows the complex

3.5 cm

patient to achieve continence and enjoy the benefits of such.

Patient selection for the procedure is as important as with

bladder augmentation because noncompliance will result in

the same myriad of complications, despite a technically per-

fect operation. Preoperative evaluation is similar to the blad-

der augmentation patient, with the acquisition of sufficient

clinical, metabolic, anatomic, and functional data to develop

a detailed surgical plan.

The goals of the continent urinary diversion include the

creation of a reservoir of adequate capacity and compliance,

nonrefluxing ureteric implantations, a continent cutaneous

stoma, and a minimum of complications.

Although the gastrointestinal tract again provides for the

reservoir, several key differences exist with an augmentation.

Colon and stomach have assumed a larger role because the

musculature of the tenia coli and stomach allow for more re-

liable nonrefluxing ureteric and catheterizable channel anas-

tomoses. The three most common types of continent

reservoir in children are (1) a reservoir fashioned solely from

ileum (Kock pouch), (2) a gastroileal composite, and (3) an

ileal reservoir (Indiana pouch).⁹⁵ Each has a myriad of varia-

12-14 cm

tions described, all attempting to decrease complications and

assist construction. However, because published reports in

children are usually limited to small numbers, each reservoir

having subtle variations and no published direct comparisons,

it is impossible to determine an ideal reservoir.^55,95,99 There-

fore the reconstructive surgeon must be familiar with several

techniques because each has advantages that may require ex-

ploitation with any clinical situation.

FIGURE 118-9

Normally, a 2-cm segment of ileum can be opened along

its antimesenteric border and tubularized for an effective channel. A

KOCK POUCH

slightly longer piece (3.5 cm) can be partially divided, both ends tubular-

ized, and reanastomosed for a spiral Monti, for situations demanding more

Kock first described a continent ileostomy in 1971^100-101 and

channel length.

from this developed the Kock pouch in 1982.¹⁰² This continent

ileal reservoir was among the original nonorthotopic

Several authors have described continent catheterizable

bladder substitutions used and remains popular today.^103-105

tubes fashioned from native bladder. Casale’s original descrip-

It requires the construction of an efferent nipple for continence

tion of the “intravesical channel”⁹⁷ was modified by Rink.⁹⁸

and an afferent limb for the prevention of reflux. This tech-

Although continence rates of

100% were reported, the

nically demanding aspect usually requires the use of stapling

technique is hampered by a 45% incidence of stomal stenosis.

devices, and these can be the source of its most significant

Although still a useful technique if an intraperitoneal pro-

complications (stone formation) and long-term failure rate.¹⁰⁶

cedure can be avoided, it has been largely replaced by the

Approximately 80 cm of ileum is harvested in adults, with

appendicovesicostomy and reconfigured ileovesicostomies.

the proximal 15 to 20 cm used in an isoperistaltic fashion to

These channels provide a more convenient and more so-

create the antireflux mechanism. The distal 12 to 15 cm are

cially acceptable means of catheterization. It is especially ben-

used for the continent cutaneous stoma. These lengths are de-

eficial for those with a sensate urethra and in the obese or

creased appropriately depending on the size of the child. The

wheelchair-bound female. It also assists caregiver comfort

bowel is intussuscepted through its full thickness, and this is

and, most importantly, patient independence.

secured by three rows of gastrointestinal staples, although

absorbable mesh has also been described.¹⁰⁷ Significant mod-

ifications include removing the distal

6 staples from the

CONTINENT URINARY RESERVOIRS

device,¹⁰⁶ stripping the distal mesentery,¹⁰⁸ and the use of

If the entire bladder has been replaced by nonurothelial tissue

absorbable staples.¹⁰⁹

(usually gastrointestinal) and requires emptying by means

other than the urethra, it is referred to as continent urinary di-

GASTROILEAL POUCH

version. Although popular and with many refinements over the

past several decades, it is not commonly used in pediatrics

The advantages of both gastric and ileal segments can be max-

today because generally the bladder can be incorporated into

imized while offsetting their complications by incorporating

the reconstruction.⁵⁰

them both into a composite reservoir. The metabolic derange-

A few diagnoses such as bladder agenesis or malignancy

ments complement each other, as the acidic gastric secretion

resulting in cystectomy will require complete bladder

will neutralize the absorptive properties of the colon or

CHAPTER 118

INCONTINENT AND CONTINENT URINARY DIVERSION

1495

ileum.^110-112 Furthermore, in patients at high risk for short

STRUCTURAL COMPLICATIONS

gut syndrome, as in cloacal exstrophy, it allows a minimum

of valuable absorptive tissue to be lost.⁵⁰ However, it is a more

Structural complications include the requirement of a second

complex reconstruction, requiring two anastomoses and lon-

augmentation, spontaneous perforation, and long-term malig-

ger operating time, but is a valuable alternative for select

nancy potential. A secondary augmentation may be required

patients.

in up to 6% of patients,⁶⁶ and most are due to high intravesical

pressures from persistent bowel contractility.^117-118 The hall-

mark clinical signs are incontinence or hydronephrosis with

INDIANA POUCH

screening ultrasound, and this is confirmed with urodynamic

The ileocecal segment has been popularized due to the poten-

studies.

tial continence or antireflux mechanism inherent to the ileo-

A spontaneous perforation can be a fatal complication and

cecal valve. Many surgical techniques have been described,

must not be underestimated. Early urine leaks are likely due to

in the attempt to maximize cutaneous continence, simplify

technical error, but late complications usually originate in the

the surgical procedure, and minimize complications. The In-

bowel, approximately 1 cm from the anastomotic line.⁵⁰ Pa-

diana group modified the pouch described by Gilchrist and

tients often present later in the course, as their neurologic def-

Merricks with a unique plication method that has retained

icit impedes symptoms. Therefore sepsis and death are

its popularity. An Indiana pouch uses the detubularized ce-

realistic possibilities, and a high index of suspicion must pre-

cum as its reservoir, with ureters implanted in a nonrefluxing

vail. Diagnosis is with a CT cystogram and treatment is usually

manner into the tenia. The ileum is then plicated to the ileo-

by laparotomy and primary closure,⁷⁸ but conservative treat-

cecal valve, which is reinforced by Lembert sutures (Fig. 118-10).

ment with catheter drainage has been successful in select

Continence has been reported in 95% to 99%,^113-114 in part due

patients.¹¹⁹

to its large capacity.¹¹⁵ Complication rates have been acceptable,

The development of an adenocarcinoma is concerning due

as low as 0.6%,¹¹³ but not all surgeons have reported such

to the well-documented occurrence following ureterosigmoi-

success.¹¹⁶

dostomy.^120-124 It arises from the ureterointestinal junction

and occurs in these patients with a 7000-fold risk over the

general population.¹²³ Although a tumor has been reported

as soon as 3 years after augmentation,^125-126 the mean latency

COMPLICATIONS FROM THE

is 21.5 to 26 years.^30,123 At our institution, 3 malignancies

INCORPORATION OF INTESTINE

have occurred in our series of more than 500 augmentations.

IN THE URINARY TRACT

All patients died of metastatic disease, with a mean time from

Despite the popularity of using the gastrointestinal tract as a

augmentation to diagnosis of 19 years.¹²⁷ Husmann and col-

urinary reservoir, the potential complications are numerous

leagues¹²⁸ have suggested that patients with neurogenic blad-

and can be significant. A broad categorization would include

ders, exstrophy, and other congenital anomalies requiring CIC

(1) complications due to structural defects, (2) complications

are at higher risk for malignancy regardless of whether enter-

secondary to the loss of the intestinal segment, (3) complica-

ocystoplasty is performed. The risk of carcinoma (both adeno-

tions due to secretions, and

(4) complications from

carcinoma and transitional cell) in this patient population is

absorption.

increased with exposure to other carcinogens (e.g., tobacco)

and immunosuppression.¹²⁹ Although most surgeons appre-

ciate the risk, definitive guidelines for surveillance have not

been established. Annual cystoscopy has been recommended

to begin 3 to 10 years after augmentation.^30,50

LOSS OF INTESTINAL SEGMENT

Removal of an intestinal segment places the patient at risk for a

bowel obstruction, and this occurs in approximately 3% of

cases.^50,60,65,130 Because many of these are due to internal her-

niation through the pedicle of the augment, Leonard and col-

leagues¹³¹ have recommended early exploration to minimize

the risk of augmentation ischemia.

The removal of a gastrointestinal segment for CUR or aug-

mentation is usually well tolerated; however, bowel dysfunc-

tion has been reported in 10% to 54% of patients.^132-133

Removal of the ileocecal valve can result in problematic diar-

rhea and rectal incontinence, especially in the neurogenic

population.^134-135 Loss of the distal ileum can also result in

diarrhea, in these cases due to an interruption in the entero-

hepatic circulation,¹³⁶ but can usually be prevented by leaving

the distal 15 to 20 cm intact. Treatment of mild cases is usually

successful with anion-exchange resins.⁵⁴

FIGURE 118-10

The Indiana pouch uses the ileocecal valve as a conti-

Vitamin B₁₂ deficiency can develop in up to 35% of patients

nence mechanism and the cecum for urinary storage.

following an

80-cm small bowel resection for a Kock