UrologySchool.com

BLADDER CANCER: ORTHTOPIC URINARY DIVERSIONS

Background

Ureterosigmoidostomy is the oldest form of urinary diversion.
Urinary diversion has developed along 3 paths: a conduit form of diversion, continent cutaneous diversion, and most recently orthotopic diversion.
Orthotopic neobladder
- Most closely resembles the original bladder in both location and function.
- Relies on the intact external rhabdosphincter continence mechanism
- Avoids the difficulties associated with the efferent continence mechanism of continent cutaneous reservoirs.
- Seldom requires intermittent catheterization
- Voiding is accomplished by relaxation of the pelvic floor musculature (as in normal voiding) along with a concomitant increase in intraabdominal pressure (Valsalva maneuver)
Compared to continent cutaneous diversion, orthotopic diversion allows natural voiding, is simpler to construct, and is less likely to require revision surgery at a later date
Demonstration in cystectomy specimens that urethral involvement was rare in the absence of tumor at the bladder neck was the key finding that allowed application of orthotopic urinary diversion to women undergoing cystectomy

Basic principles for successful outcome of continent orthotopic urinary diversion (3):

Adequate external sphincter mechanism and non-obstructed urethra
Compliant reservoir to maintain a low pressure throughout the filling phase

Best achieved by opening the bowel segment longitudinally to completely detubularize it and folding it to create a spheric shape

Capacious reservoir to allow for reasonable voiding intervals

In general, this should be at least 300-500 mL once the pouch is mature
All bowel segments effectively stretch over time if there is adequate outflow resistance, though colonic segments do not stretch up as easily
Small bowel, when available, has advantages over colon in terms of wall compliance and ability to stretch, as well as reduced mucous formation

Patient selection for orthotopic diversion

It is estimated that ≈80-90% of male patients and 75% of female patients undergoing cystectomy are potential candidates for neobladder construction from a purely medical standpoint
UrologySchool.com Summary of Contraindications (6):
1. Insufficient bowel length
2. Unwillingness or inability to self-catheterize
3. Renal insufficiency
4. Hepatic dysfunction
5. Indications for urethrectomy
  1. Positive urethral margin
    - CIS in bladder, multifocal tumour, bladder neck tumour, locally advanced disease are not contraindications
  2. Males with:
    1. High grade or invasive urethral disease distal to the prostatic urethra
    2. Suspected prostatic stromal involvement
  3. Females with bladder neck tumours
6. Severe urethral stricture disease

Note that first 4 also apply to non-orthotopic continent urinary diversions

Oncologic considerations
- Locally advanced tumour stage
  - Many avoid continent orthotopic diversion in patients with locally extensive disease based on 2 factors:
    - Concern about the possible impact of local recurrence on the neobladder itself
    - Belief that these patients are doomed to suffer distant recurrence and have a shortened life expectancy and will not benefit from the neobladder
  - Local recurrence even for patients demonstrating locally advanced or lymph node positive disease is relatively infrequent and a significant proportion of these patients will be long-term survivors and may benefit from continent diversion
    - Risk of recurrence is not increased by careful preservation of the urethra during the cystectomy
  - If local tumor recurrence does develop in patients with an orthotopic diversion, only a minority will develop problems related to the urinary diversion itself
  - The presence of extravesical disease should not preclude orthotopic diversion.
Patient-related considerations

A number of patient-related factors need to be considered when advising a patient about the best form of urinary diversion, including the patient’s general health and social circumstances, baseline renal function, presence of a healthy urethra and functioning sphincter muscle, manual dexterity, and previous treatments including pelvic radiation, prostate surgery, or bowel resection. Equally important is the patient’s personal preference and attitudes about the risk of incontinence, potential need to self-catheterize, and management of an external appliance.
Patients with poor general health, high surgical risks, the frail elderly, difficult social circumstances, or poor cognitive function are probably best managed with an ileal conduit
Chronologic age and obesity are not contraindications for orthotopic diversion
Renal function

Urinary electrolytes including urea, potassium, and chloride are reabsorbed from the small bowel mucosa with excretion of sodium and bicarbonate, resulting in an increased acid load that must be processed by the kidneys. In patients with compromised renal function, hyperchloremic metabolic acidosis can develop along with worsening dehydration, uremia, nausea, and bone loss.
Compromised renal function (eGFR <35-50 ml/min [<45 as per 2019 AUA MIBC Guidelines or serum Cr >150-200 μmol/L (1.7 – 2.2 mg/dL) is a contraindication for continent neobladder reconstruction

The exact level of acceptable renal function for consideration for continent diversion is unclear

Orthotopic diversion does not lead to progressive renal dysfunction in patients with normal renal function before surgery

Hepatic dysfunction

Similar to the kidneys, the liver must deal with an increased metabolic load with urinary diversion

Manual dexterity and willingness to do self-catheterization

All patients considered for continent diversion should be willing and able to do self-catheterization since it is impossible to predict which patients will require catheterization to empty, and retention can occur many years after the initial surgery

Insufficient bowel length

Orthotopic diversion requires more length (ileal reservoirs require 60-75cm) than ileal conduit (10-15cm)
A patient with multiple prior bowel resections, such as those with Crohn’s, may be at risk of developing chronic diarrhea or even short bowel syndrome after an additional 60 cm of small bowel is resected. In these patients, alternatives to orthotopic diversion such as a sigmoid neobladder should be considered.
In general, prior bowel resections can be managed by carefully dissecting out all of the small bowel, taking down any adhesions before performing the diversion.
- In patients with prior bowel resection, it is critical to identify the old bowel anastomosis and, whenever possible, take that down and use that site as one end of the continent reservoir. This avoids potential devascularization of the bowel segment between the old and new bowel anastomoses.

Urethral stricture disease

Severe urethral stricture disease in men and women is a contraindication for orthotopic diversion.

Prior pelvic radiation

In carefully selected patients, orthotopic lower urinary tract reconstruction can be performed after definitive, full-dose pelvic irradiation.
Ileum should not used for diversion in patients with previous pelvic radiation
Previous high-dose prostate radiation (external beam or brachytherapy) or a vaginal implant for cervical cancer cause more scarring in the rhabdosphincter area than does external beam radiation for either bladder cancer or other malignancies. Interstitial seed implants for prostate cancer often end up in the levator muscles and urogenital diaphragm and may result in severe scarring around the area of the external sphincter.
Patients with prior radiation are at increased risk of several complications, even with an ileal conduit diversion.
Preoperative evaluation including cystoscopy is mandatory to evaluate the integrity of the mucosa around the area of the sphincter. However, it may not be possible to accurately predict the degree of radiation damage found at surgery, so careful intraoperative tissue assessment and determination of the condition of the urethra, ureters, and bowel must be performed to make a final decision about the feasibility of orthotopic diversion. These patients should always be counseled preoperatively that the orthotopic diversion may not be possible.

Prior prostate surgery

Patients who have had a prior radical prostatectomy may have a particularly difficult dissection around the proximal urethra at the prior vesicourethral anastomosis. Nevertheless, this is often feasible with careful dissection.
With careful dissection a patient who was continent after the initial radical prostatectomy surgery can be expected to have an acceptable result with a neobladder.

External sphincter damage

Poor sphincter function in a patient who is highly motivated to undergo orthotopic diversion may be managed with a concomitant or delayed anti-incontinence procedure

Surgical techniques for continence preservation during radical cystectomy

The innervation of the striated urethral rhabdosphincter arises from the branches of the pudendal nerve and is most important to maintain continence in patients with an orthotopic neobladder
The striated rhabdosphincter muscle fibers are concentrated in the anterior and lateral to the proximal urethra
The surgical dissection at the prostatic apex in men and bladder neck in women must be carefully and precisely performed to achieve optimum continence while taking care not to compromise the oncologic effectiveness of the surgery.
Anterior Apical Dissection in the Male Patient

Minimal manipulation of the muscle fibers of the rhabdosphincter, fascial attachments, and corresponding innervation is essential to providing optimal urinary continence
Obtain careful control of the DVC and avoidance of deep suture bites into the pelvic floor muscles
Further technical details in Campbell’s

Preservation of the Urethra in the Female Patient

The endopelvic fascia and levator muscles should not be disturbed
In women undergoing neobladder reconstruction, preserving the uterus and its supportive ligaments:
1. Eliminates the risk of vaginal fistula
2. Improves sexual function
3. May decrease urinary retention
4. Improved daytime continence
Whenever possible the bladder is dissected completely off the anterior vaginal wall rather than excising it, whether the uterus is removed or not. However, a deeply invasive tumor on the posterior bladder or trigone may necessitate excision of a portion of the anterior vaginal wall. This does increase the risk of subsequent pouch-vagina fistula but is not an absolute contraindication to orthotopic reconstruction.
The issue of nerve-sparing cystectomy in women is controversial. It appears that preservation of the perivaginal nerves may not be absolutely required to maintain continence in women.

Techniques for orthotopic bladder substitution

Choice of bowel segment

Excellent functional and clinical outcomes with voiding can be achieved regardless of the segment of bowel chosen as long as the principles of preservation of the rhabdosphincter as a continence mechanism and construction of an adequate capacity, low-pressure reservoir are maintained
Reservoirs made of detubularized ileum or ileum and colon together appear to have the greatest compliance and lowest likelihood of generating intermittent high-pressure contractions.

The urodynamic characteristics of the ileum appear to be superior to those of the colon
Advantages of neobladders made of ileum (6):
1. Larger capacity
2. Lower filling pressures
3. Lower maximum capacity pressures
4. Better compliance
5. More mobile mesentery
  - Generally reaches to the urethra without much difficulty
  - In patients with short ureteral length because of malignancy or other pathology of the ureters, an ileal pouch with a “tail” (such as the Studer) can be extended to reach all the way to the renal pelvis
6. Decreased mucous production and decreased reabsorption of urinary electrolytes in the mature reservoir due atrophy of the intestinal mucosa as it is exposed to urine over time.
The primary disadvantage of using distal ileum lies in the potential loss of absorption of vitamin B12.
Contraindications to use ileum for diversion(3):
1. Short bowel syndrome
2. Inflammatory small bowel disease
3. History of extensive pelvic irradiation where the ileum may have been affected
Whenever ileum is available, it is preferentially use it for orthotopic diversion.
Stomach and sigmoid colon have been found to have particularly poor compliance and high pressures

See Intestinal Segments Chapter Notes

Need to prevent reflux

The addition of an antireflux mechanism does not appear to be necessary for preservation of the upper tracts and prevention of infections, at least in the intermediate term

Studies that have compared refluxing versus non-refluxing urinary diversion have been limited, in general, by short follow-up, patient selection bias, retrospective design, or relatively small patient numbers
Any mechanism introduced to prevent reflux may potentially cause upper tract obstruction. Afferent valve obstruction is often clinically silent

General perioperative management

Perioperative management of patients undergoing cystectomy and orthotopic diversion is similar to those undergoing other types of diversion
A pelvic drain should be placed in every patient. The authors leave the drain until the pouch has healed because of occasional late leakage if the catheter gets plugged at home.
There is no consensus on the ideal management of ureteral stents or catheters in patients undergoing orthotopic diversion. Most authors recommend the use of ureteral stents in the early postoperative period
When patients return at the 3-week postoperative mark, if there is minimal drainage from the drain (<100 mL during 24 hours), the catheter is removed, followed by the drain. Routine pouchograms or radiographic studies of the neobladder are not routinely performed unless a significant output from the drain is observed.
Patients receive education throughout the perioperative period regarding catheter management, pelvic floor exercises, and proper voiding technique.

Surgical techniques

Ileal reservoirs

Most ileal reservoirs use 60-75 cm of terminal ileum, which is detubularized and folded in a variety of ways to attempt to create a spheric shape. Modifications primarily include variations in the exact folding technique and variations in management of the ureters, with or without an antireflux mechanism
In general, all reservoirs are closed with continuous absorbable suture. The use of nonabsorbable suture and metal staples should be avoided because of the potential for stone formation
The 2 most popular configurations are the Hautmann W-neobladder (and its various modifications) and the Studer pouch neobladder. The T pouch and extraserosal tunnel techniques both provide an antireflux mechanism when that is felt to be advantageous.
Ileal neobladder (Hautmann Pouch)

See BJUI Surgical Atlas for details and figures
Intentionally large-capacity, spheric (W configuration) ileal reservoir that is constructed in an attempt to optimize initial volume and potentially reduce nighttime incontinence.
A segment of terminal ileum of ≈70 cm is selected. The bowel is reconstituted, and the mesenteric trap is closed. The ileal section that reaches the urethra most easily is identified and marked with a traction suture along the antimesenteric border. The isolated bowel segment is then arranged in either an M or W shape and is opened along the antimesenteric border except for a 5-cm section along the traction suture where the incision is curved to make a U-shaped flap.
The 4 limbs of the M or W are then sutured to one another with a running absorbable suture. A small full-thickness segment of bowel is excised in the site for the urethral anastomosis, which is then performed with the sutures tied from inside the neobladder. Once the ileal neobladder is situated in the pelvis and the urethral sutures are tied, the ureters are implanted from inside the neobladder through a small incision in the ileum at a convenient site. The remaining portion of the anterior wall is then closed with a running absorbable suture
This pouch has a larger initial capacity than the Studer pouch, which may assist in earlier continence. However, it may also result in an increased incidence of late urinary retention and increased electrolyte reabsorption from the pouch.

Studer pouch

See BJUI Surgical Atlas for details and figures
Uses a long, afferent, isoperistaltic, tubular ileal segment that is believed to prevent vesicoureteral reflux when the patient voids by Valsalva maneuver
The advantages of this bladder substitute include the simplicity of construction, the lack of a requirement for surgical staples, and the ability to accommodate short ureters.
The reservoir portion uses the optimal double-folded U configuration
The terminal portion of the ileum (54-56 cm long) is isolated approximately 15-20 cm proximal to the ileocecal valve. The distal mesenteric division is made along the avascular plane between the ileocolic artery and terminal branches of the superior mesenteric artery. The proximal mesenteric division, however, is short and provides a broad vascular blood supply to the reservoir. In addition, a small window of mesentery and 5 cm of small bowel proximal to the overall ileal segment are discarded, ensuring mobility to the pouch and small bowel anastomosis. Bowel anastomosis is performed using staplers.
The Studer pouch is created from 40-44 cm of distal ileum with each limb of the U measuring 20 to 22 cm and a proximal 15-cm segment of ileum used as the afferent limb. If ureteral length is short or compromised, a longer afferent ileal segment (proximal ileum) may be used. The proximal end of the isolated afferent ileal segment is closed with absorbable suture. The isolated ileal segment is opened about 2 cm away from the mesentery, and the incised ileal mucosa is then oversewn with two layers of a running 3-0 polyglycolic acid suture

Camey II
Serous-lined extramural tunnel
Orthotopic Kock Ileal Reservoir (Hemi-Kock)

The Kock ileal reservoir was first used as a continent cutaneous ileal reservoir incorporating intussuscepted nipple valves for both the afferent (antireflux) and efferent (continence) limbs. This subsequently evolved into an orthotopic form of diversion in which the afferent intussuscepted limb was maintained to prevent urinary reflux
The technical difficulty of the intussuscepted nipple valve and the associated complications, along with the development of effective alternative techniques, has made this neobladder procedure primarily of historical interest.

T pouch modification

In an effort to preserve an antireflux mechanism but avoid the potential long-term complications seen with the Kock nipple valve, as well as to allow for more flexibility in managing the ureters, the T pouch was developed as a modification of serous-lined ureteral tunnel

Colon and ileocolic pouches

Orthotopic neobladders constructed completely of colon are a good option for patients with multiple previous small bowel resections or who have diseased ileum (e.g. Crohn’s, previous pelvic radiation)
Colon segments are less distensible than ileal segments and may be more likely to produce higher pressure waves causing incontinence. As a consequence, initial volume should be larger than for an ileal pouch. Combined colon and ileal segments can mitigate this problem.
Orthotopic Mainz Pouch (Mainz III)
Le Bag Pouch
Right Colon Pouch
Sigmoid Pouch

Patients who are candidates for radical cystectomy often have a redundant sigmoid colon, which is readily available for use.
The only concern is the potential compromise of the vasculature of the distal colon segment because of interruption of branches of the internal iliac artery during the cystectomy. It is important, therefore, to maintain as much of the vascular supply to both ends of the bowel anastomosis as possible. Some patients will complain of frequent stools or rectal urgency for a period of time after sigmoid colectomy.

Use of Minimally Invasive Techniques for Orthotopic Diversion

Postoperative recovery in most series has only been modestly improved compared with open series, with longer operative times but decreased blood loss.
Postoperative complications demonstrate mixed results.
In the RAZOR trial, which showed non-inferiority of robotic RC vs. open for 2-year PFS and similar rate of complications, 20-24% underwent neobladder diversion

Complications of orthotopic diversions

Overall rate of complications, hospital stay, and reoperation rates are not increased by use of continent diversion compared with ileal conduit diversion
The major long-term problems with continent cutaneous diversion relate to malfunction of the efferent continence mechanism, and open surgical revision is often required
Early post-operative complications

Occur at similar rate in all types of urinary diversions:

Bleeding, infection, thrombotic events, cardiovascular, pulmonary, and GI complications

Ureteral complications are possible with any type of diversion
Urine leaks can occur with any type of diversion but are more common in continent diversion than in conduits because of the long suture lines; with good catheter drainage and properly managed stents and drains these usually resolve with observation alone as long as a urinoma does not form

If a patient has an undrained leak, an attempt at percutaneous drainage and/or bilateral nephrostomy tube placement is preferable to open surgical repair.

Open surgical repair is extremely difficult during the first few weeks after the initial surgery and is likely to be complicated by enterotomies and a risk of fistula formation.
≈5% of patients require some sort of percutaneous drain or nephrostomy tube placement during the early postoperative period to manage these problems.

Late post-operative complications

Occur at similar rate in all types of urinary diversions:

Bowel obstruction, thrombotic events, and cardiovascular complications
Ventral hernias are quite common and may be in part related to the need for increased abdominal pressure to empty the neobladder

Late complications directly related to diversion include:

UTI
Ureteroileal or afferent limb obstruction
Urethral stricture
Upper tract and pouch stones
Pouch-vaginal fistula
Pouch perforation
Incontinence
Other than incontinence, these complications tend to be less common in orthotopic diversion than in continent cutaneous diversion, and many if not most can be managed by endoscopic procedures and rarely require open surgical revision

UTI

Although symptomatic urinary infections do occur, asymptomatic colonization of the neobladder with bacteria is also very common, although less common than in continent cutaneous diversion unless the patient is on intermittent self-catheterization.
Asymptomatic bacteriuria should not be treated and is likely to simply encourage development of resistant organisms. If local symptoms suggest an infection, it should be confirmed whenever possible by a culture in this patient population.
A patient who develops a febrile infection after the initial few months should be evaluated for possible upper tract obstruction and incomplete emptying.

Ureteroileal or afferent limb obstruction

The rate of ureteroileal stricture is identical to that in ileal conduit diversion, and is influenced by the type of anastomosis. The direct end-to-side Leadbetter or the combined Wallace anastomoses with interrupted fine absorbable sutures have been shown to have the lowest risk of stricture (≈3-6%)
Obstruction from an antireflux valve has been seen. These may be clinically silent until the patient develops bilateral hydronephrosis or even renal failure

Urethral stricture

Actual stricture of the neobladder-urethral anastomosis is rare

Upper urinary tract and pouch stones

Pouch stones were very commonly seen in the Kock neobladder because of the use of surgical staples to maintain the intussuscepted nipple valve but have been rare in the Studer and Hautmann neobladders, which are made entirely with absorbable suture

Pouch-vaginal fistula

A unique complication of orthotopic neobladder in women that can be quite difficult to repair.
Reported incidence is 5-10%, and the risk is increased if a portion of the anterior vaginal wall is excised along with the cystectomy specimen and in irradiated patients.
Prevention methods include:
1. Leaving the vagina intact whenever it is safe from an oncologic standpoint
2. Careful watertight closure of the vaginal cuff when it is opened
3. Placement of an omental flap between the vagina and neobladder, secured to the perivaginal tissue on either side of the urethral anastomosis.
Fistula should be ruled out in any woman with persistent significant incontinence after the first few months of recovery.
- This is most easily done with a careful pelvic examination and with methylene blue instilled into the neobladder if necessary.

Pouch perforation

Potentially life-threatening complication
Rare in continent diversion in general, especially in orthotopic diversion because outlet resistance is usually low.
- Risk may be increased in patients who have had previous radiation therapy.
Typically presents with acute abdominal pain and distention, often with signs of sepsis
CT cystogram is usually diagnostic
In general, these patients should be managed with exploration and repair, although conservative management with percutaneous drains has been described

Incontinence

Daytime continence

Gradually improves over the first 6-12 months
Ultimately achieved in 80-90% of both male and female patients

Preserving the uterus may be associated with improved daytime continence

Nighttime continence

Improves more slowly and may continue to improve beyond 12 months
One of the most bothersome sequelae of neobladders, persisting in 20-50% of patients
Results in part from the absence of neurologic feedback and sphincter detrusor reflex, as well as decreased sphincter tone at night

Factors influencing continence rates include:
- Age; older patients take longer to regain continence than younger patients
- Intestinal segment used
- Possibly the application of a nerve-sparing technique
The evaluation and management of urinary incontinence after orthotopic diversion should be delayed until the neobladder has had time to expand. This may take 6-12 months after surgery
Physical therapy with biofeedback focused on the pelvic floor muscles may help some patients attain initial continence.
Urodynamic investigation may be indicated to ensure adequate capacity, without pressure waves, especially if colon is used for the neobladder.
- If reduction in maximal urethral closure or low Valsalva leak pressure is demonstrated, anti-incontinence procedures (such as transurethral injection of bulking agents, AUS, artificial urinary sphincter or urethral sling) can be considered.
  - In patients undergoing slings, use of infrapubic bone anchors or a prepubic approach may provide the safest surgical options to avoid injury to the pouch or bowel

Urinary retention

Occurs in 4-10% of men and 20-60% of women
Patients with incomplete emptying may have acute retention but more often have urinary infections or the new onset of overflow incontinence on presentation. They may also be discovered on routine follow-up with a palpable suprapubic mass, or distended reservoir or new-onset hydronephrosis on imaging.
Rectal or vaginal examination and cystoscopy should be performed in patients who develop retention, to rule out a urethral anastomotic stricture or tumor recurrence
Management

Intermittent self-catheterization preferred
Pharmacologic intervention for patients with urinary retention does not appear to be an effective measure to improve this voiding dysfunction.
Biofeedback training in pelvic floor relaxation may be helpful.
Many of these patients have a flap of mucosa causing the obstruction that may be incised endoscopically with good effect
Hernias should be identified and surgically repaired

A significant number of patients with orthotopic reservoirs will develop abdominal wall or incisional hernias postoperatively.
These fascial defects will reduce the efficiency in completely evacuating the neobladder by reducing the ability to effectively increase intra-abdominal pressure.

In women it appears that posterior prolapse of the pouch may contribute to late retention, and posterior support by means of omental flaps and sacrocolpopexy has been advocated

Follow-up for patients with orthotopic diversion

There is no consensus on the ideal follow-up regimen for patients with orthotopic diversion.
The follow-up regimen can be divided into 3 time segments:
1. Early evaluation (first 4 months) to identify early ureteroileal anastomotic strictures caused by technical difficulties or poorly vascularized distal ureters.
2. Middle period (4 months to 3 years) primarily focused on detecting cancer recurrence. This is best managed with CT or other cross-sectional imaging, which also allows evaluation of the upper tracts and reservoir for stones or obstruction. The frequency of the follow-up can be risk-adapted according to the pathologic findings at the time of cystectomy and the risk of subsequent recurrence.
3. Long-term follow-up (beyond 3 years) to detect pouch stones, late upper tract obstruction, and urothelial carcinoma arising in the urethra or upper tracts.
Follow-up should include rectal and pelvic examination and urethral cytology to identify urethral recurrence, which occurs in ≈10% of males and rarely in females

Quality of life after orthotopic urinary diversion

There are not clear data showing an overall quality-of-life advantage for patients undergoing neobladder reconstruction, and most patients will clearly adapt to whatever specific challenges their urinary diversion presents to them. Nevertheless, when presented with the option, most patients will choose orthotopic diversion simply because it seems the most natural and avoids a permanent stoma, and having this option may encourage patients to more readily undergo definitive treatment of their bladder cancer. Patients must, however, have realistic expectations about the risk of incontinence and the possible need for self-catheterization.

Indiana Pouch

Non-orthotopic, continent urinary diversion
Uses a buttressed ileocecal valve as a dependable continence mechanism that can withstand the trauma of intermittent catheterization
Involves isolating a segment of terminal ileum ≈10 cm in length along with the entire right colon to the junction of the right and middle colic artery blood supplies.
After bowel continuity is reestablished, appendectomy is performed. The entire right colon is opened along its antimesenteric border, and ureteral-taenial implants are fashioned. The ileocecal junction is buttressed according to various reported techniques. With nonabsorbable sutures, interrupted Lembert sutures are taken over a distance of 3-4 cm in two rows for the double imbrication of the ileocecal valve. The second row of sutures should attempt to bring the opposite mesenteric edges of ileum together, usually over a 12- to 14-Fr catheter. These two rows of sutures should be placed approximately 8 mm from one another, and the initial suture in each row may be taken in a purse-string fashion around the cecal margin as well.
Early complications include pouch leak, transient small bowel obstruction
Late complications include incontinence, stomal stenosis, parastomal hernia, stones, small bowel obstruction

Questions

What are the contraindications to orthotopic urinary diversion?
What electrolyte abnormality can develop in patients with renal insufficiency and neobladders?
What the possible benefit of preserving the uterus in women undergoing neobladder reconstruction?
What is the target volume of a mature neobladder?
Approximately how much bowel is used for a ileal neobladder vs. conduit?

Answers

What are the contraindications to orthotopic urinary diversion?
1. Uretherectomy indications (positive urethral margin, bladder neck tumour in women, high-grade or invasive disease distal to prostatic urethra or suspected prostatic stromal invasion invasion in men)
2. Renal insufficiency (from Chapter 97)
  1. eGFR <45 based on 2019 AUA MIBC guidelines
  2. Significant proteinuria
  3. Unable to acidify urine pH < 5.8 after ammonium load
  4. Unable to concentrate urine ≥ 600 mOsm/kg after water deprivation test
3. Hepatic dysfunction
4. Inability or unwillingness to self-catheterize
5. Insufficient bowel length
6. Severe urethral stricture disease
What electrolyte abnormality can develop in patients with renal insufficiency and neobladders?
- Hyperchloremic metabolic acidosis
What the possible benefit of preserving the uterus in women undergoing neobladder reconstruction?
1. Reduced risk of vaginal fistula
2. Improves sexual function
3. Reduces risk of urinary retention
4. Improved daytime continence
What is the target volume of a mature neobladder?

300-500 mL

Approximately how much bowel is used for a ileal neobladder vs. conduit?

Neobladder 60-75cm vs. 10-15cm

References

Wein AJ, Kavoussi LR, Partin AW, Peters CA (eds): CAMPBELL-WALSH UROLOGY, ed 11. Philadelphia, Elsevier, 2015, chap 99