Fistula and Urethral Diverticulum

Ralph R. Chesson Jr.,

Okechukwu A. Ibeanu

INTRODUCTION

Vesicovaginal fistulas are a most distressing condition for women. Their constant drainage of urine creates emotional and physical distress affecting their everyday life. In developing countries they are social outcasts because of the constant smell of urine. They withdraw from society. In the United States postoperative fistulas are becoming a more common cause of malpractice cases because of the long social isolation these patients endure.

Luiz de Mercado in Valladolid, Spain, first used the term fistula instead of rupture (1). Although John Peter Mettauer, a rural Virginia surgeon, reported the first successful cure of a fistula in the United States (2), James Marion Sims, a rural Alabama surgeon, is recognized as the father of American gynecology and is most associated with the repair of vesicovaginal fistula (3).

Neglected obstetric labor and gynecologic surgical complications are the main etiologic factors for the formation of vesicovaginal fistulas. Worldwide, most vesicovaginal fistulas are from neglected obstetrics, especially in sub-Saharan Africa, where the true incidence is unknown. Some report an incidence of 1 or 2 per 1,000 deliveries (4), but recent presentations and discussions at an international fistula conference at Johns Hopkins, Baltimore, Maryland, in August 2005 suggest that all estimates are inaccurate (5).

The problem of obstetric fistula has been eradicated in the United States, Scandinavia, and Western Europe, with the exception of vesicouterine/vesicocervical fistulas. Today most fistulas seen in the United States are from gynecologic surgery, in particular abdominal hysterectomy (6). Fistulas from gynecologic malignancy and/or radiation therapy are quite rare. The high prevalence of obstetric fistulas still remains a problem in Africa and less developed regions of Asia and Oceania (7). Until there are improvements in obstetric care, especially the elimination of prolonged obstructed labor, the problem of obstetric fistula will persist in these areas.

We will discuss the gynecologic and obstetric fistulas separately as their cause and cure are different. Obstetric injuries are a “field” injury with ischemic changes to the bladder and vagina from the prolonged pressure of an impacted fetal head against the tissues (7). Most gynecologic injuries, with the exception of radiation injuries, are a local injury with minimal changes in the adjacent tissues.

GYNECOLOGIC FISTULA

Etiology

In gynecologic practice in the United States, vesicovaginal fistulas most commonly follow hysterectomies. Specifically, 88% of the vesicovaginal fistula cases are complications of gynecologic and obstetric surgery (1) and 82% are from hysterectomy (6). Urologic procedures account for 6% of cases, while radiation treatment, trauma, and malignant disease account for approximately 4% of cases (8). Vesicovaginal fistulas result from “faulty” dissection of the bladder from the cervix and lower uterine segment. Distortion of tissues is caused by uterine leiomyomata, previous cesareans, and other pelvic conditions such as endometriosis
and pelvic inflammatory disease that lead to loss of surgical planes. Tissue trauma, electrocautery, infection, smoking, radiation, and diabetes contribute to local tissue breakdown and poor wound healing. Wound healing has four phases: coagulation, inflammation, fibroplasia, and remodeling. During the fibroplasia phase the rate of formation of fibroplastic collagen peaks at day 7 and formation continues for 2 to 3 weeks. It is this time period during which tissue breakdown is most likely to occur. Inadvertent suture in the bladder may contribute to poor healing, but Meeks (9) suggests that a suture in the bladder is not associated with fistula formation. Seventy percent to 80% of bladder injuries during gynecologic surgery go unrecognized (10). Radiation fistulas occur with endarteritis and tissue ischemia with necrosis and fibrosis. These radiation-induced lesions may present months to years after treatment (11). Minimizing the risk of injury at the time of surgery is the goal of the surgeon (Table 17.1).

Presentation

Patients may complain of urine loss immediately following the procedure once the urethral catheter is removed if there is a gross bladder defect. This would entail a combined vaginal opening as well as a laceration or other direct injury to the bladder, allowing the urine to escape from the vagina and resulting in symptomatic urinary leakage. More commonly the leakage starts in 2 to 4 weeks after surgery, once the sutures placed through the vagina and the bladder have started to dissolve. Other symptoms include hematuria at the time of surgery and in the first few days after surgery. Fever and chills may precede loss of urine, followed by defervescence. Abdominal flank pain may also be present, but this association is more common for ureterovaginal fistula. This latter case is accompanied by a transient serum creatinine elevation lasting 1 or 2 days. In most cases of posthysterectomy vesicovaginal fistula, however, patients remain relatively symptom-free and complain of only occasional abnormal vaginal discharge until there is sudden urinary leakage soaking through pads and clothing. It has been estimated that 50% of postsurgical fistulas present after 10 days (8). Signs of peritonitis and ileus frequently accompany intraperitoneal leakage of urine, which occurs when there has been direct bladder injury and the site remains open to the peritoneal cavity, while the vagina is tightly closed. The serum creatinine will be elevated as long as there is peritoneal urine leakage.

TABLE 17.1 Surgical Techniques for Minimizing Lower Urinary Tract Injuries During Gynecologic Surgery

Proper positioning of the patient to allow abdominal and vaginal access
Adequate exposure and lighting of the surgical field
Surgeon familiarity with the anatomy of the space being entered
Performance of blunt and sharp dissection where appropriate. Blunt dissection is appropriate along certain established spaces in the pelvis (i.e., pubocervical space), but sharp dissection is needed to enter the space. When unsure, always use sharp dissection.
Be aware of the course of the ureter and protect it from injury.
Control bleeding with pressure, suction, identification of source, and correction.
Avoid large pedicles.
Continuous bladder drainage for abdominal cases
Intraoperative cystoscopy for all hysterectomy and pelvic reconstructive surgery to ensure the integrity of the lower urinary tract system (10)
Minimize use of electrocautery in the area of the bladder in proximity to the vaginal cuff.

Diagnosis

The initial management of leakage of urine from the vagina should be prompted by a high index of suspicion for a vesicovaginal fistula. Unless very small, the fistula may be visualized with a vaginal speculum. Diagnosis is aided by instilling methylene blue dye into the bladder. If the blue is not seen vaginally, a tampon is placed in the vagina and the patient is asked to walk for a few minutes. Blue coloration of the tampon at the vaginal vault location indicates loss from a fistula. Blue color on the end closest to the vaginal entry indicates urethral loss. If no blue is seen, then an ureterovaginal fistula must be considered. Either indigo carmine intravenously or phenazopyridine (Pyridium) orally may be given to stain the urine as it exits the kidney. Again, placing a tampon in the vagina will help to determine if the leakage is from an ureterovaginal fistula. If still unclear, intravenous
pyelography should be performed, but especially if there is a suspicion of a compound fistula including the bladder and ureter. Cystoscopy is indicated to view the bladder site of a vesicovaginal fistula and proximity to the ureters. If there has been ureteral compromise, cystoscopy with intravenous indigo carmine and retrograde studies may also be performed. Contrast cystography can also be used as a diagnostic test; however, it is not as sensitive and has a higher false-negative rate than other tests.

Urinalysis with culture and sensitivity should be performed. At the time of cystoscopy suture material should be removed from the area of the fistula to facilitate resolution of inflammation prior to repair.

Treatment

Nonsurgical

Five percent to 10% of small vesicovaginal fistulas may heal spontaneously with prolonged bladder drainage using a suprapubic or urethral catheter. Bladder drainage and the use of a Foley catheter connected to a birth control diaphragm may lessen perineal irritation by diverting the urine flow. Four weeks of drainage should allow time for healing if the defect is going to close. Otherwise, surgical intervention is required.

Surgical

Traditionally, an interval of at least 3 to 6 months was advised before the surgical repair of a vesicovaginal fistula. Once the inflammation has resolved, it is considered appropriate to proceed with repair, and this has not led to failures of the Latzko colpocleisis procedure in uncomplicated unradiated patients (12). Fistula associated with radiation therapy should not be immediately repaired, as the radiation scarring will continue to affect tissues for a much longer time.

Several surgical techniques have been described for closure of vesicovaginal fistula. Regardless of the technique used, any repair must be performed with strict adherence to basic surgical principles in order to maximize the chances of a successful repair. Meticulous tissue dissection should be performed in order to adequately expose the fistula site, and all layers of closure should be tension-free, watertight, and nonopposing. If deemed necessary, a tissue interposition flap (Martius) should be employed in order to enhance blood supply and healing.

The surgical repair may be approached transvaginally or transabdominally. Most urogynecologic surgeons favor the transvaginal route, with the transabdominal route reserved for fistulas involving the ureter or other organs, including bowel. The use of specialty vaginal retractors such as those made by Lone Star Medical Products (www.lsmp.com) and/or the use of a generous episiotomy will allow adequate access to most fistulas, including most “high” fistulas.

Techniques

Latzko Partial Colpocleisis

Latzko’s method of partial colpocleisis (13) has the advantage of minimal tissue dissection as well as avoiding incision of the bladder (Fig. 17.1). After patient positioning and exposure of the operative site with proper retractors, the fistula is again visualized using methylene blue dye if necessary. Repeat cystoscopy is performed if necessary. After locating the fistula, stay sutures are placed between 3 and 4 cm from the fistula at four quadrants (2, 5, 8, and 11 o’clock) to delineate the area of epithelium to remove. The principle of the Latzko repair is a partial colpocleisis of the upper vagina to close the fistula tract without actually excising it. All vaginal epithelium must be removed to prevent epithelial inclusion cyst formation or failure of the fibromuscularis tissues to scar together. A generous amount of epithelium removal will increase the success rate of this procedure. Generally, a 1.5- to 2-cm border around the fistula margin is sufficient. The incision is closed in two or three layers with interrupted 3-0 or 4-0 polyglactin sutures anterior to posterior.

If the procedure is a repeat procedure or vascularity is compromised, a Martius flap is placed (Figs. 17.2). The Martius flap utilizes the fat pad overlying the bulbocavernosus muscle. The fat pad is mobilized, usually leaving the posterior pedicle attached. It is brought into the vaginal incision though a subepithelial tunnel and is sutured to the fibromuscularis prior to closing the vaginal epithelium.

Postoperative drainage should be from 10 to 14 days either by indwelling Foley or suprapubic catheter. The method of drainage and length should be individualized to the surgeon’s comfort with his or her estimation of the quality of the closure and the vascularity of the tissues.

Excisional Transvaginal Repair of Vesicovaginal Fistula

Sometimes the amount of scarring precludes a standard Latzko approach, and the fistula tract must be excised (Fig. 17.3). This procedure is also utilized in most obstetric fistulas to be discussed later. The fistula is exposed as in the Latzko repair and the fistula tract is excised. If significant scarring is encountered, Potts scissors (sharp-pointed
scissors) are helpful in the dissection. The vaginal epithelium is mobilized from the underlying fibromuscularis, and the fistula is excised. The margins of the defect in the bladder mucosa and muscularis are identified and closed without tension. The bladder is closed with 3-0 or 4-0 polyglactin sutures in two layers. Pubocervical fibromuscularis is then used to interpose between the bladder and vaginal mucosa. The vaginal mucosa is closed in similar fashion with the same suture. A Martius flap should be considered in cases where the risk of breakdown is relatively high. Bladder drainage postoperatively is as described above.

FIGURE 17.1 ● Latzko procedure. (A) Stay sutures or Lone Star hooks are placed at 10, 2, 4, and 8 o’clock. (B) A rectangular excision of epithelial tissue at least 3 cm from the fistula tract is excised from the underlying fibromuscularis. (C) The epithelium has been excised from the underlying fibromuscularis with at least a 5 × 5-cm defect. (D) The first layer is closed with interrupted delayed absorbable 3-0 sutures on an RB or SH needle. (E) After two layers of suture, watertight integrity has been checked and the epithelium is being closed. (F) The epithelium has been closed with interrupted sutures.

Transabdominal Repair

While some urologists favor this approach (Figs. 17.4, 17.5, 17.6), more surgeons reserve the transabdominal route for cases of vesicovaginal fistula complicated by ureteral injury, radiated fistula, or cases with bowel involvement. This route may also be used for vesicouterine fistula when uterine preservation is desired.

Transvesical Approach

The incision is usually made at the dome of the bladder, exposing and identifying the fistula location. Indigo carmine may be given intravenously to help in identification of the ureteric orifices.
Ureteral catheters are placed if needed. The fistula is excised and the bladder muscle is dissected off the anterior vaginal wall, separating both structures. The bladder and vaginal defects are closed in nonopposing fashion using 3-0 or 4-0 polyglactin sutures. This approach may be hampered by limited surgical access to the fistula site.

FIGURE 17.2 ● Martius graft. (A) The fat pad over the bulbocavernosus muscle is mobilized, maintaining its vascular pedicle from posterior and freed from its superior vascular pedicle. (B) A tunnel under the vulvovaginal epithelium is made into the vaginal defect over the fistula and the flap is pulled through with a clamp. (C) The vulvar incision is closed; a drain is placed if there is difficulty with hemostasis, and the flap is pulled into the vaginal epithelial defect over the closed fistula. (D) The flap is sutured to hold it in place over the defect. (E) The vaginal epithelial defect is closed.

A posterior bladder wall incision offers greater field of view through an incision over the bladder dome extended down to the fistula site. The fistula is excised, followed by dissection of the bladder off the vagina, and the defects in the vaginal wall and bladder wall are closed separately.

An omental flap may be placed between the bladder and vagina. The use of peritoneal flaps has been described with good results. Omentum is particularly suitable because it has excellent lymphatic drainage and blood supply.

Other Techniques

Various surgeons have reported differing success rates using solutions such as the injection of fibrin sealant into the fistula track (14,15). Fulguration of
the track has also been described (16), but deep fulguration will more likely devitalize tissue and complicate future closure. It may be reasonable to attempt these techniques in very small fistulas.

FIGURE 17.3 ● Excision of fistula tract. (A) A probe is placed through the urethra into the fistula tract. (B) A retractor is placed through the tract to inspect for the location of the ureteral orifices. Stay sutures have been placed; even better is the use of the Lone Star retractor. (C) The fistula tract is excised sharply with a knife or Potts scissors. (D) The fistula tract is almost excised. (E) The first-layer closure with fine interrupted delayed absorbable sutures. (F) The second layer is completed and is checked for watertight integrity prior to closure. A Martius flap might also be utilized at this time, also prior to closing the epithelium with interrupted sutures.

Postoperative Care

The duration of catheter drainage has not been studied to know the optimal interval. Usually drainage is for 10 to 14 days. Vaginal cases are usually discharged the following day. Antibiotic prophylaxis is given during surgery and is optional thereafter. Patients are to refrain from intercourse or use of tampons for 6 weeks until the vaginal incision is completely healed. Fluids are pushed to keep the urine dilute. If the bladder has been entered (abdominal repair or excision of fistula tract) care must be taken to prevent blood clot formation, and some surgeons will use a large-bore catheter or even combine suprapubic and Foley drainage. Activity is minimized to prevent catheter irritation of the bladder and repair site. Patients should not be working or doing household activities during catheter drainage. Some surgeons will perform a cystogram through the catheter prior to catheter removal to ensure there is no remaining fistula tract, although this is not required in most cases. It is important to ensure the patient voids easily on catheter removal and does not develop an overdistended bladder at any point in the postoperative period.

FIGURE 17.4 ● Abdominal repair of vesicovaginal fistula. (A) Bladder opened, with outline of area to be resected before placement of initial suture line. (B) Extramucosal approximation by sutures, resulting in approximation of bladder mucosa. (From Lee RA. Atlas of gynecologic surgery. Philadelphia: WB Saunders, 1992. By permission of Mayo Foundation.)

FIGURE 17.5 ● Abdominal repair of vesicovaginal fistula (continued). Previously closed vagina suture line separated from second layer of inverting suture within wall of bladder. (From Lee RA. Atlas of gynecologic surgery. Philadelphia: WB Saunders, 1992. By permission of Mayo Foundation.)

FIGURE 17.6 ● Abdominal repair of vesicovaginal fistula (continued). Mobilized omentum sutured in place between closed bladder and vagina. (From Lee RA. Atlas of gynecologic surgery. Philadelphia: WB Saunders, 1992. By permission of Mayo Foundation.)

Complications

Success rates as high as 98% have been reported following surgery for simple vesicovaginal fistula repair (6). Complications include recurrence of the fistula, infection, stress urinary incontinence, de novo urge incontinence, and dyspareunia. Radiation-induced fistulas and cancer-related fistulas pose a special problem. These can be difficult to repair and are associated with a higher recurrence and complication rate.

OBSTETRIC FISTULA

Obstetric fistulas are an ancient problem of childbirth. Figure 17.7 is helpful in understanding the etiology of obstetric fistulas in the developing world in the context of the socioeconomic conditions of these countries. Women of many developing countries, especially sub-Saharan Africa, have a very low socioeconomic status. They have few choices in life. Most have little education and are forced to stop school when they are given in marriage at a young age. Childbearing occurs before pelvic growth is completed, and there are almost no medical facilities available. Labor is frequently in the hut of the parents of the father for supposed good luck, and it is only after 1 or 2 days of second-stage labor that an effort may be made to transport the laboring patient to the nearest facility, usually a day away on a wagon or by walking. Help from lay midwives include gishiri, the cutting of the vagina in hope of making more space, many times causing the fistula. The stillbirth rate exceeds 75% in these obstructed labors and the maternal mortality approaches 1%. The fistula rate is estimated to be 1%. The injury to the pelvic floor depends on where the head impacts in its descent. Bladder base, trigone, urethra, and rectovaginal tissues are susceptible to breakdown from ischemia. Poor nutrition, chronic anemia, and infections, added to poor hygiene due to a lack of clean water and supplies, accelerates the deterioration of the lesion. The vulva and perineum become constantly exposed to the stream of urine, with subsequent excoriation and maceration of the tissues. Additionally, many have a footdrop that has an unclear etiology. Finally, the worst injury is the social isolation of these patients. Most are divorced and even rejected by their family (7,17,18). They have no resources, with resultant malnutrition, illness, and premature death.

Epidemiology

The socioeconomic conditions of these countries are the main etiology of these fistulas (19). Most patients with fistula are less than 150 cm tall and weigh less than 44 kg. Most have been in labor for at least 2 days prior to being transported for care.

Classification of Fistulas

There is no universally accepted classification system for obstetric vesicovaginal fistula. Using size or location has limitations regarding the outcomes. Old classification systems such as the Hamlin’s, which refer to an “easy” fistula or a “difficult” fistula, are not helpful to surgeons who have not done thousands of fistulas (20). Elkins described a classification according to location, but again this is not helpful in prediction of the outcome of repair, though it is helpful in the understanding of vesicovaginal fistula (21) (Fig. 17.8).

Waaldijk based his classification system on the involvement of the closure mechanism and was able to relate advancing stage to poorer results (Table 17.2) (22). Figure 17.9 shows a Waaldjik stage IIB fistula with circumferential defect.

Roenneburg and Wheeless (Table 17.3) presented a classification including size, relation to bladder trigone, and involvement of the closing mechanism that had some correlation to success (International Fistula Conference, July 2005, Johns Hopkins). They looked at the statistics of the International Organization for Women and Development, Inc., mission trips to Niamey, Niger, from 2003 to 2005 (Table 17.4).

Arrowsmith presented a scoring system on 229 patients in Jos, Nigeria, that predicted success of repair (International Fistula Conference, July 2005, Johns Hopkins). After analysis of all factors he found that the amount of scarring and the degree of involvement of the urethral closure mechanism were predictive of success of being dry after surgical repair (Table 17.5). A score of 3 or less had an 85% dry rate. A score of 4 or more had a 41% dry rate.

Previous classification systems were not effective in predicting “success.” Fistula closure is not a “success” if the patient has intrinsic sphincter deficiency or intractable urge incontinence from a small contracted bladder. There may be just a pinpoint opening in the vaginal epithelium, but once in surgery there may be no viable tissue for repair until the dissection defines the true size of the fistula. There is a need for an internationally agreed upon classification system. This will allow surgeons to compare their data and help to determine the best approach to the repair.

FIGURE 17.7 ● Obstetric fistula pathway: origins and consequences. (From Wall LL, Arrowsmith SD, Briggs ND, et al. The obstetric vesicovaginal fistula in the developing world. Obstet Gynecol Survey 2005;60(supp 1):S1-51, by permission.)

FIGURE 17.8 ● Obstetrical fistula by classification. (From Elkins TE. Surgery for the obstetric vesicovaginal fistula: a review of 100 operations in 82 patients. Am J Obstet Gynecol 1994;170(4): 1108-1120, with permission.) (A) Vesicocervical fistula. (B) Juxtacervical fistula. (C) Midvaginal vesicovaginal fistula. (D) Suburethral vesicovaginal fistula. (E) Urethrovaginal fistula.

FIGURE 17.9 ● Patient with total circumferential loss of entire urethra. Note the catheter inserted into the bladder at the bladder neck, but no remaining urethra remains except fragments.

TABLE 17.2 Classification of Obstetric Vesicovaginal Fistula According to Waaldijk

Type I: Not involving urethral closure mechanism

Type II: Involving the urethral closure mechanism

A: Without (sub)total urethral involvement

1: Without circumferential defect

2: With circumferential defect

B: With (sub)total urethral involvement

1: Without circumferential defect

2: With circumferential defect

Type III: Miscellaneous ureter/other fistulas

Perioperative Considerations

Evaluation for Other Lesions

The presence and anatomic extent of multiple fistulas must be investigated.

Nutritional Status

Many patients in sub-Saharan Africa with vesicovaginal fistula will have chronic nutritional deprivation. Many will decrease their fluid intake to minimize
urine leakage. Nutritional build-up prior to surgery should commence in the weeks before surgery, with nutritional supplements (rich in protein, vitamins, and iron) and in some cases blood transfusion. They must also increase their hydration, as this will be important in their surgical care (23).

TABLE 17.3 Wheeless Classification of Obstetric Vesicovaginal Fistula

Stage I: <2-cm fistula, above the trigone; not involving urethra, trigone, ureteric ridge

Stage II: 2- to 4-cm fistula, above the trigone

Stage III: 4- to 6-cm fistula, above the trigone

Any size fistula involving the continence mechanism of the proximal urethra, urethrovesical junction, trigone, or ureteric ridge

Stage IV: 6-cm fistula or greater

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