A fistula represents a nonanatomic epithelialized connection between two or more body spaces.

• General Considerations
  • Vesicovaginal fistulae (VVF) are the most common acquired fistula of the urinary tract.
  • VVF have been known about since ancient times
  • 1663 Hendrik von Roonhuyse first described surgical repair
  • 1852, James Marion Sims published his now famous surgical series describing a method of surgical treatment of VVF using silver wire in a transvaginal approach.
• Etiology
  • The most common cause of VVF differs in various parts of world.
    • In the industrialized world, the most common cause (75 percent) is injury to the bladder at the time of gynecologic surgery; usually abdominal hysterectomy
    • Obstetric trauma accounts for very few VVF in the United States and other industrialized nations.
    • In the developing world, VVF most commonly occur as a result of prolonged labor
      • Obstetric fistulas tend to be larger, located distally in the vagina, and may involve the proximal urethra.
  • Other causes of VVF include urologic or gynecologic instrumentation, pelvic malignancy (cervical cancer, etc.), inflammatory diseases, radiation therapy, and trauma.
• Presentations
  • The most common complaint is constant urinary drainage per vagina although small fistulas can present with intermittent wetness that is positional in nature.
    • VVF must be distinguished from urinary incontinence due to other causes.
  • Patients may also complain of recurrent cystitis, perineal skin irritation due to constant wetness, vaginal fungal infections, or rarely, pelvic pain.
  • When a large VVF is present, patients may not void at all and simply have continuous leakage of urine into the vagina.
  • VVF following hysterectomy or other surgical procedures may present upon removal of the urethral catheter or 1 to 3 weeks later with urinary drainage per vagina.
    • VVF resulting from hysterectomy are usually located high in the vagina at the level of the vaginal cuff
  • VVF resulting from radiation therapy may not present for months to years following completion of radiation.
• Evaluation
  • History: etiology, chronology, h/o prior pelvic or GU surgery
  • Physical examination
    • A pelvic examination with a speculum should always be performed in an attempt to locate the fistula and assess the size and number of fistulae.
    • Palpate for masses or other pelvic pathology that may need to be addressed at the time of fistula repair.
    • An assessment of inflammation surrounding the fistula is necessary as it can affect timing of the repair.
    • The presence of a VVF can be confirmed by instilling a vital blue dye or sterile milk into the bladder per urethra and observing for discolored vaginal drainage.
    • A double dye test can confirm the diagnosis of urinary fistula as well as suggest the possibility of an associated ureterovaginal or urethrovaginal fistula.
  • Urine culture and urine analysis
  • Cystoscopy and possible biopsy of the fistula tract is performed if malignancy is suspected.
    • Note the location of fistula relative to ureters; repair of the fistula may require reimplantation of ureters if the fistula involves the ureteral orifice.
  • Voiding cystourethrography
    • Some small fistulas may not be seen radiographically unless the bladder is filled to capacity and a detrusor contraction is provoked.
    • Assesses for vesicoureteral reflux.
    • Examines for multiple fistulae including urethrovaginal fistula. Assesses size and location of fistula.
  • Intravenous urography and/or retrograde pyeloureterography
    • Assesses for concomitant ureteral injury and/or ureterovaginal fistula.
  • Cross-sectional pelvic imaging (MRI/CT) if malignancy is suspected.
• Therapy
  • Nonsurgical management
    • Catheter drainage is the initial treatment in most cases.
    • Fulguration of the fistula followed by catheter drainage has been shown to have some efficacy in small (less than 5 mm), uncomplicated fistulae.
    • Adjuvant measures (such fibrin glue, etc.) have been used
  • Surgical management
    • Success rates approach 90 to 98 percent regardless of surgical approach.
      • Adherence to basic surgical principles are essential to achieve success in the repair of all urinary fistula.
      • Choice of the optimal surgical approach to VVF is controversial
        • Numerous factors to consider.
      • No single approach is applicable to all VVF.
        • Transabdominal, transvaginal, transvesical approaches described
        • Regardless of approach:
          • Maximal urinary drainage (urethral and suprapubic catheters) is maintained postoperatively.
          • A cystogram is usually obtained 2 to 3 weeks following repair to confirm successful closure.

Table I: Principles of Vesicovaginal Fistula Repair

• Good hemostasis.
• Judicious use of cautery.
• Adequate exposure of the fistula tract.
• Watertight closure of each layer.
• Well-vascularized, healthy tissue for repair.
• Multiple layer closure.
• Tension-free, nonoverlapping suture lines.
• Adequate urinary drainage after repair.
• Prevention of infection (use of pre-, post-, and intraoperative antibiotics).
• Adequate preoperative nutritional repletion

Table II: Abdominal versus Transvaginal Repair of Vesicovaginal Fistula

References

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