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Orthotopic neobladder

Senior Resident em Christian Medical College & Hospital
10 de Aug de 2017
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Orthotopic neobladder

  1. ORTHOTOPIC NEOBLADDER Dr Prateek Laddha SR Urology CMC Ludhiana
  2. HISTORY OF ORTHOTOPIC URINARY DIVERSION • Since the early 1900s • Ureterosigmoidostomy is the oldest form of urinary diversion. • 1st reported urinary diversion into a segment of bowel  Simon in 1852. • A number of technical modifications of the ureterosigmoidostomy ensued, particularly related to the ureteral implantation technique (Hinman and Weyrauch, 1936). • (Leadbetter, 1951; Goodwin et al, 1953). introduction of an antireflux tunneled anastomosis of the ureter into the sigmoid colon • rates of obstruction and • ascending pyelonephritis in patients with ureterosigmoidostomy
  3. • Ureterosigmoidostomy remained the diversion of choice until the late 1950s, • but long-term electrolyte imbalance, • upper tract obstruction and infection, and • secondary malignant neoplasms arising at the ureteral implantation site were observed • In 1950 Bricker refined and popularized  ileal conduit form of urinary diversion, • building on an original description by Zaayer in 1911 (Zaayer, 1911; Bricker, 1950).
  4. • The ileal conduit is a technically simple, reliable form of urinary diversion that became widely accepted and became the gold standard to which other types of urinary diversion were compared until the 1980s. • It continues to be by far the most common form of urinary diversion performed throughout the world today for patients undergoing cystectomy. • Long-term complications with the [1970s]. • hyperchloremic metabolic acidosis and • pyelonephritis were substantially less common than in patients with ureterosigmoidostomy,
  5. PATIENT SELECTION • all patients who undergo radical cystectomy may be considered at least potential candidates for orthotopic urinary diversion. • Factors can be divided into cancer-related factors and patient factors.
  6. Oncologic Factors Risk of Urethral Recurrence in Men • Primary oncologic contraindication for orthotopic diversion is the presence of urothelial carcinoma at the urethral margin on intraoperative frozen section at the time of cystectomy. • It has been a practice to counsel patients with documented • prostatic mucosal, • ductal, or • stromal invasion about the increased risk of urethral recurrence if the urethra is left in situ, • weigh that risk against any perceived advantage of an orthotopic diversion.
  7. Risk of Urethral Recurrence in Women: • Risk factors for urethral involvement included • increased grade, • stage, and • lymph node involvement, but the presence of CIS did not predict urethral involvement. • Vaginal wall involvement was also a major risk factor for urethral involvement. • The urethra can be safely preserved in selected female cystectomy patients provided that neither preoperative biopsy specimens of the bladder neck nor intraoperative frozen section specimens of the proximal urethra demonstrate any tumor or atypia.
  8. • However, approximately half of patients with bladder neck tumors had a normal (tumor-free) proximal urethra. • In all cases, intraoperative frozen-section analysis of the proximal urethra correlated with and was correctly confirmed by final permanent section. • These results suggest that one may depend on the intraoperative frozen section to determine the feasibility of orthotopic diversion.
  9. Locally Advanced Tumor Stage • Many urologists are hesitant to perform continent orthotopic diversion in patients with locally extensive disease. This is based on two factors: (1) concern about the possible impact of local recurrence on the neobladder itself and (2) a belief that these patients are doomed to suffer distant recurrence and have a shortened life expectancy and will not benefit from the neobladder. • If local tumor recurrence does develop in patients with an orthotopic diversion, only a minority will develop problems related to the urinary diversion itself.
  10. • most patients could anticipate normal neobladder function even in the presence of locally recurrent disease.
  11. • The low risk of local recurrence showed that in this cohort of patients the oncologic efficacy of the operation was not compromised include 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.
  12. Patient-Related Factors • Age • The clear consensus is that chronologic age alone is not a contraindication for continent diversion and that options should be considered for each patient on the basis of other factors • Renal Function • One of the most important contraindications for continent neobladder reconstruction is compromised renal function. • In patients with compromised renal function, hyperchloremic metabolic acidosis can develop along with worsening dehydration, uremia, nausea, and bone loss. • Serum creatinine level of < 1.7 to 2.2 mg/ dL (150 to 200 μmol/L) or an estimated CC of greater than 35 to 40 mL/min is recommended for patients considering continent diversion
  13. Body Habitus • Obesity is not a contraindication • Placing the urethral sutures and working with the thick bowel mesentery may be challenging. • An obese patient may be better served with orthotopic diversion because of the difficulty constructing a functional conduit stoma with a very thick abdominal wall.
  14. • Manual Dexterity and Willingness to Do Self-Catheterization • Urethral Stricture Disease or External Sphincter Damage • Severe urethral stricture disease in men and women is a contraindication for orthotopic diversion. • Prior Pelvic Radiation • Patients with prior radiation are at increased risk of several complications, even with an ileal conduit diversion. • Orthotopic lower urinary tract reconstruction can be performed after definitive, full-dose pelvic irradiation. • 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
  15. Prior Prostate Surgery or Bowel Resection • Prior abdominal or pelvic surgery may also present challenges for the surgeon performing orthotopic diversion. Patients who have had a prior radical prostatectomy may have a particularly difficult dissection around the proximal urethra at the prior vesicourethral anastomosis. • Short bowel syndrome
  16. SURGICAL TECHNIQUES FOR CONTINENCE PRESERVATION DURING RADICAL CYSTECTOMY • Anterior Apical Dissection in the Male Patient • Attention to anatomic and surgical detail is important to optimize functional and clinical outcomes in patients undergoing orthotopic diversion. Minimal manipulation of the muscle fibers of the rhabdosphincter, fascial attachments, and corresponding innervation is essential to providing optimal urinary continence • If a nerve-sparing approach is planned, the urethra may be divided after the lateral pedicles are taken down to the bladder (anterior branches of the internal iliac vessels) before the posterior dissection is performed. The prostate is then dissected in a retrograde fashion off the rectum and bilateral neurovascular bundles, and the posterior pedicles are divided last.
  17. • Care should be taken to avoid deep suture bites into the complex or levator muscles, which could injure the continence mechanism. • Frozen-section analysis of the circumferential distal urethral mucosal margin (prostatic apex) on the cystectomy specimen is performed to exclude tumor involvement. If there is no evidence of tumor, orthotopic reconstruction may be performed. If there is tumor at the prostatic apex, the urethral stump can be excised or a total urethrectomy may be performed at this time to obtain a negative margin, and a cutaneous diversion constructed.
  18. Preservation of the Urethra in the Female Patient • A standard female cystectomy includes removal of the uterus, cervix, and ovaries (anterior exenteration). However, in selected females with clinically lower-stage disease, a number of authors have advocated preservation of the uterus and ovaries. • Whether the uterus is removed or not, whenever possible the bladder is dissected completely off the anterior vaginal wall rather than excising it. However, a deeply invasive tumor on the posterior bladder or trigone may necessitate excision of a portion of the anterior vaginal wall.
  19. • A patient with a significant tumor at the bladder neck or with palpable extension into the vaginal wall is a poor candidate for neobladder and should undergo en bloc urethrectomy and cutaneous diversion.
  20. • Preparation of the female urethra for an orthotopic neobladder. The fatty tissue overlying the anterior urethra is swept off the endopelvic fascia and the vesicourethral junction is carefully identified by positioning the Foley catheter at the bladder neck. Note that the endopelvic fascia and periurethral tissue anteriorly are not disturbed.
  21. • Regardless of the form of vaginal reconstruction, a well-vascularized omental pedicle graft should be placed between the reconstructed vagina and the neobladder and secured to the endopelvic fascia at either side of the urethral stump to separate the suture lines and prevent fistula formation between the vaginal and urethral anastomosis, which may help support the pouch posteriorly.
  22. 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.
  23. • The primary disadvantage of using distal ileum lies in the potential loss of absorption of vitamin B12. • Isolation of the segment of bowel to be used for the diversion must be performed carefully to preserve blood supply to the pouch, as well as to the bowel anastomosis. Need to Prevent Reflux: • It is clear that any mechanism introduced to prevent reflux may also potentially cause upper tract obstruction.
  24. General Perioperative Management • Ileal Reservoirs • ileal reservoirs use from 60 to 75 cm of terminal ileum, which is detubularized and folded in a variety of ways to attempt to create a spheric shape. • The use of nonabsorbable suture and metal staples should be avoided because of the potential for stone formation. • two most popular configurations around the world are the Hautmann W-neobladder (and its various modifications) and the Studer pouch neobladder.
  25. Camey II • The Camey II orthotopic substitute is a modification of the original Camey bladder substitute, which was a simple segment of ileum anastomosed to the ureters and urethra. • The modification includes detubularization and folding to eliminate peristaltic activity. • A fingertip opening is made in the preselected area for the ileourethral anastomosis, the entire ileal plate is brought down to the pelvis, and the urethral anastomosis is performed.
  26. Ileal Neobladder (Hautmann Pouch) • This neobladder is an intentionally large-capacity, spheric (W configuration) ileal reservoir that is constructed in an attempt to optimize initial volume and potentially reduce nighttime incontinence.
  27. Construction of the Studer neobladder (modified). • Designated segments of terminal ileum for construction of the orthotopic Studer pouch ileal neobladder. Note that the distal mesenteric division is made between the ileocolic and terminal branches of the superior mesenteric artery, which extends into the avascular plane of the mesentery. In addition, a small window of mesentery and a 5-cm segment of proximal small bowel are discarded to allow mobility to the pouch and small bowel anastomosis.
  28. • The Studer pouch is constructed from an isolated 44-cm ileal segment (placed in an inverted U configuration), which forms the reservoir portion of the pouch, and a proximal 15-cm segment of ileum to form the afferent limb. The two 22-cm ileal segments are opened 2 cm adjacent to the mesentery beginning at the apex and carried upward to the ostium of the afferent segment.
  29. • The previously incised ileal mucosa is then oversewn with two layers of a running 3-0 polyglycolic acid suture starting at the apex and running upward to the afferent limb. The reservoir is then closed by folding it in half in the opposite direction to which it was opened.
  30. • Construction of the antireflux mechanism in the T pouch. The ileum is divided between the proximal afferent ileal segment and the 44-cm segment. The dotted line depicts the incision line on the U limbs. Mesenteric windows of Deaver are opened between the vascular arcades adjacent to the serosa. Placement of small Penrose drains through each mesenteric window helps facilitate passage of sutures. The distal 3 to 4 cm of the afferent ileal segment is anchored into a serosal-lined ileal trough formed by the base of the two adjacent 22-cm ileal segments, using 3-0 silk sutures.
  31. • The previously anchored distal 3- to 4-cm afferent ileal segment is tapered over a 30-Fr catheter on the antimesenteric border. The incision of the bowel provides wide flaps of ileum that covers the tapered distal afferent ileal segment to form the antireflux mechanism in a flap-valve technique.
  32. • A mucosa-to mucosa anastomosis is performed between the ostium of the afferent segment and the edges of the ileal flaps using interrupted 3-0 polyglycolic acid suture. The mucosal edges of the ileal flaps are brought over the tapered distal portion of the afferent ileal segment and sewn using a continuous 3-0 polyglycolic acid suture.
  33. • Once the reservoir is folded in half, the anterior wall is closed with a two-layer 3-0 polyglycolic acid suture that is watertight. Note that the anterior suture line is stopped just short of the (patient) right side to allow insertion of an index finger, which will become the neobladder neck. Conversely a new buttonhole can be created at the most dependent portion of the pouch.
  34. • Each ureter is spatulated and a standard bilateral end-to-side ureteroileal anastomosis is performed using interrupted 4- 0 polyglycolic acid suture.
  35. • The reservoir is anastomosed to the urethra using the previously placed urethral sutures.
  36. Colon and Ileocolic Pouches Orthotopic Mainz Pouch (Mainz III)
  37. Le Bag Pouch
  38. • late complications with the ileal conduit such as • peristomal hernia • stomal stenosis • pyelonephritis • kidney stones • ureteral obstruction • renal deterioration became more apparent with longer follow-up
  39. • These clinical sequelae • the high-pressure reflux of infected urine or • obstruction of the upper urinary tract. • It was postulated that the addition of an antireflux technique to a conduit form of diversion could help diminish the problems of reflux and renal deterioration in these patients. • Unfortunately, with longer follow-up, similar complications with nonrefluxing colon conduits were observed.
  40. • One of the earliest continent cutaneous diversions in humans was described by Gilchrist and colleagues in 1950. • This form of urinary reconstruction incorporated a cecal reservoir with the ileocecal valve as the continence mechanism and the distal ileum as a catheterizable stoma. • The concept of a continent cutaneous diversion was subsequently reintroduced by Kock and colleagues in 1982 with a technique that was originally developed for a continent ileostomy after colectomy for inflammatory bowel disease. • It incorporated an intussuscepted nipple valve to maintain continence and avoid reflux. In animal experiments and then in humans, Kock demonstrated the importance of complete detubularization of the bowel segment and the double-folding technique that creates the most spheric shape possible.
  41. • After Kock described his results in his initial 12 patients, Skinner began performing this diversion in adults undergoing cystectomy for bladder cancer in 1982. • Although this form of urinary diversion required catheterization of an abdominal stoma, it eliminated the need for an external urostomy appliance. • The biggest challenge in the development of continent cutaneous diversion has been the design of a reliable, durable, efferent continence mechanism that is easily catheterizable.
  42. Problems • stones, • difficulty in catheterizing, • peristomal hernias, and • the development of leakage are potential problems with all of them, often necessitating open surgical revision • Today, several different reliable techniques are available to create a continent cutaneous urinary diversion, including the Indiana pouch and various other forms of right colon pouches. • These forms of diversion can potentially offer an advantage to patients over an ileal conduit, but these operations remain technically challenging and are not widely used.
  43. Early and Late Complications Both early and late complications may also be influenced by other factors such as - prior radiation therapy, - diabetes, and - other comorbidities. - Late complications are also influenced by tumor recurrence and the use of adjuvant or salvage systemic chemotherapy or radiation, and these causes may be difficult to separate out from causes related to the surgery.
  44. • Late complications not • directly related to the diversion include bowel obstruction, ventral • hernia, thrombotic events, and cardiovascular problems common • to patients in this age group.
  45. • Ventral hernias are quite common and may be in part related to the need for increased abdominal pressure to empty the neobladder. The poor fascial strength associated with advanced age and smoking undoubtedly contributes to this risk as well.
  46. • primary late complications of orthotopic diversion that are directly related to the diversion itself include • incontinence, • urinary tract infection, • ureteroileal or afferent limb obstruction, • urethral stricture, • upper tract and pouch stones, • vaginal fistula, and pouch rupture. • 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
  47. • Pouch perforation is rare in continent diversion in general, especially in orthotopic diversion because outlet resistance is usually low. The risk may be increased in patients who have had previous radiation therapy. It is a potentially life-threatening complication when it occurs. • 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, approximately 3% to 6%. Obstruction from an antireflux valve has been seen in both hemi- Kock pouches and in the extraserosal tunneled afferent limb of the T pouch
  48. • CT scans will often be misinterpreted by radiologists or urologists unfamiliar with the anatomy and/or the specific type of neobladder. • Pouch stones were very commonly seen in the Kock neobladder because of the use of surgical staples to maintain the intussuscepted nipple valve, with the incidence increasing steadily with time. Stones have been rare in the Studer and Hautmann neobladders, which are made entirely with absorbable suture.
  49. • Pouch-vaginal fistula is a unique complication of orthotopic neobladder in women that can be quite difficult to repair. • Prevention methods include • leaving the vagina intact whenever it is safe from an oncologic standpoint, • careful watertight closure of the vaginal cuff when it is opened, and • placement of an omental flap between the vagina and neobladder, secured to the perivaginal tissue on either side of the urethral anastomosis
  50. Incontinence: • The evaluation and management of urinary incontinence after orthotopic diversion should be delayed until the neobladder has had time to expand.
  51. Follow up: NO CONSENSUS • Early evaluation (first 4 months) to identify early ureteroileal anastomotic strictures caused by technical difficulties or poorly vascularized distal ureters. • 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. • 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.
  52. QUALITY OF LIFE AFTER URINARY DIVERSION • Most quality-of-life studies that have evaluated and compared patients undergoing various forms of urinary diversion have been criticized for methodologic problems that limit their conclusions. • The current body of published literature is insufficient to conclude that any form of urinary diversion is superior to another on the basis of health-related quality of life outcomes.
  53. •Thank You

Notas do Editor

  1. innovative surgeons have sought the best method to replace the original bladder when it must be removed because of either benign or malignant disease. The objective of bladder substitution is to allow volitional voiding through the urethra while eliminating the need for a cutaneous urinary stoma or intermittent catheterization. He attempted a ureterosigmoidostomy in an exstrophy patient by bringing the ureters into the rectum with the use of needles and suture to create a fistula. Although the patient died of sepsis 12 months later, this marked the first reported attempt at some form of urinary diversion (Simon, 1852) Over the following 100 years the evolution of urinary diversion was marked by a continued search for better methods and techniques to reconstruct the lower urinary tract.
  2. In the male patient involvement of the prostatic urethra is associated with a higher risk of subsequent urethral recurrence. Some evidence indicates that orthotopic diversion itself may provide some protection against urethral recurrence.
  3. The ureteroileal anastomosis is then performed via a Le Duc technique. The reservoir is completed by folding the ileal plate and suturing with a running absorbable suture. The ends of the U are anchored to the pelvic floor to reduce tension (Fig. 99-4). A modification of the Camey II has been described by Barre and colleagues (1996). This places the ileum in a Z configuration and reportedly has the advantages of shorter length requirements, improved reservoir capacity, and potentially improved functional (continence) results (Barre et al, 1996).
  4. Construction of the modified Camey II. A, The ileal loop is folded three times (Z shaped) and incised on the antimesenteric border. B, The reservoir is closed with a running suture to approximate the incised ileum. C, The urethral anastomosis is performed, and the ureters are implanted using a Le Duc antireflux technique.
  5. Construction of the Kock ileal reservoir. A, A total of 61 cm of terminal ileum is isolated. Two 22-cm segments are placed in a U configuration and opened adjacent to the mesentery. The more proximal 17-cm segment of ileum will be used to make the afferent intussuscepted nipple valve. B, The posterior wall of the reservoir is then formed by joining the medial portions of the U with a continuous running suture. C, A 5- to 7-cm antireflux valve is made by removing the mesentery under that segment and then intussuscepting the afferent limb with the use of Allis forceps clamps. D, The afferent limb is fixed with two rows of staples placed within the leaves of the valve. E, The valve is then fixed to the back wall from outside the reservoir with additional surgical staples. F, After completion of the nipple valve, the reservoir is completed by folding the ileum on itself and closing it, leaving the most dependent end of the suture line open for the urethral anastomosis.
  6. Construction of the Hautmann ileal neobladder. A, A 70-cm portion of terminal ileum is selected. The isolated segment of ileum is incised on the antimesenteric border. B, The ileum is arranged into an M or W configuration with the four limbs sutured to one another. C, After a buttonhole of ileum is removed on an antimesenteric portion of the ileum, the urethral anastomosis is performed. The ureteral anastomoses are performed using a Le Duc technique or direct implantation and are stented, and the reservoir is then closed in a side-to-side manner. As an alternative, the two ends of the W may be left slightly longer as a short chimney on either side for implantation of the ureters.
  7. A, B, C, D, E1,
  8. Construction of the Mainz ileocolonic orthotopic reservoir. A, An isolated 10 to 15 cm of cecum in continuity with 20 to 30 cm of ileum are isolated. B, The entire bowel segment is opened along the antimesenteric border. An appendectomy is performed. C, The posterior reservoir is closed by joining the opposing three limbs together with a continuous running suture. D, An antireflux implantation of the ureters through a submucosal tunnel is performed and stented. E, A buttonhole incision in the dependent portion of the cecum is made to provide for the urethral anastomosis. F, The reservoir is closed side to side with a cystostomy tube and the stents exiting.
  9. Construction of Le Bag (ileocolonic) orthotopic reservoir. A, A total of 20 cm of ascending cecum and colon, with a corresponding length of adjacent terminal ileum, is isolated. The bowel is opened along the entire antimesenteric border, and the two incised segments are then sewn to each other. This forms the posterior plate of the reservoir. B, This reservoir is folded and rotated 180 degrees into the pelvis with the most proximal portion of the ileum (2 cm nondetubularized) anastomosed to the urethra. C, Modification is performed with complete detubularization of the bowel segment, which is then anastomosed to the urethra. (Copyright Baylor College of Medicine.)
  10. These concepts are the cornerstone of current cutaneous and orthotopic reservoirs.
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