Vaginal Fistula Repair
Jeffrey P. Wilkinson
Obstetric fistula is a condition that is largely found in low-resource countries where access to emergency obstetrics care and cesarean delivery for prolonged obstructed labor does not exist or is delayed. When obstetric fistula occurs in high-resource settings, it is usually during difficult cesarean delivery owing to adhesions from prior surgery or abnormal placentation. Prevention of obstetric fistula as a result of cesarean delivery is almost always possible by employing meticulous surgical technique, a high index of suspicion, and a number of simple diagnostic measures. It is axiomatic that repair of injuries at the time of delivery is better than repairing these at a later date.
Patients with obstetric fistula present at any time after delivery, from immediately to weeks after, depending on the nature of the injury. Typical vesicovaginal fistula (VVF) symptoms include involuntary loss of urine at all times. The patients typically report “urine running down my legs” or standing and a sudden gush of urine from the vagina without any preceding urge. Also, with larger fistulas, women often do not have any spontaneous voiding. The bladder cannot hold any urine because of the position of the fistula so it cannot fill sufficiently to void. In patients who are able to hold any urine and who can void, either a very small fistula or a ureteral fistula is suspected.
Obstetric fistula is fortunately an uncommon occurrence. Therefore, evaluation of the condition is not well taught in training, and most providers in high-resource settings do not routinely see women with fistula. Obstetric fistula can be very complex, especially after prolonged obstructed labor. These two factors encourage referral to a specialist for surgical repair. Typically, obstetric fistula that results from cesarean delivery in high-resource settings is fundamentally different than those resulting from prolonged obstructed labor. Surgeons who have not managed fistula from obstructed labor, even if they are accomplished pelvic surgeons, in general, should not attempt to repair fistula from prolonged obstructed labor.
Obstetric fistula is a complication of labor and/or operative delivery and globally is primarily caused by prolonged obstructed labor. In high-resource settings, obstetric fistula is more likely related to complicated cesarean delivery than obstructed labor. For the purposes of this chapter, we will italicize material related to low-resource settings.
Physical examination begins with a general physical examination with special attention to the presence of foot drop which can result from prolonged squatting in obstructed labor and/or compression of nerves passing through the pelvis with prolonged obstructed labor.
The patient is placed in lithotomy position.
Extensive urine dermatitis or vaginal scarring can make the examination uncomfortable.
Often, the patient with extensive injury from prolonged obstructed labor requires examination under anesthesia to stage the injury and establish the level of care needed for successful surgery.
A disarticulated Graves speculum or Sim speculum assists in inspecting the anterior vagina along with the cervix or vaginal vault.
A dye test is indicated for small fistulas whereas large VVF are easily identified without dye. Large VVF are exceptionally rare outside of low-resource setting.
It is customary to measure the depth of the bladder, length of the urethra, and vaginal depth during the examination. This can be extremely uncomfortable in women with severe obstetric trauma, sexual assault, or other issues. A comprehensive examination can be delayed until the time of anesthesia if the surgeon is reasonably confident that the only treatment option is surgical (almost all cases).
Bladder stones (Figure 6.2.1) are common in women with obstetric fistula because they limit their water intake to decrease leakage. The surgical approach would be different if a bladder stone is present (a VVF should not be repaired with a bladder stone present as the stones often pose a significant infection risk. In our experience, most fistula repaired with a concurrent stone removal ultimately fail). The stone should be removed through the fistula if at all possible, but otherwise through a retropubic, extraperitoneal cystotomy. Bladder stones can be detected by bimanual examination, ultrasound, or probing the bladder with a metal catheter or uterine sound.
A dilute dye solution (methylene blue or other dye) is instilled retrograde into the bladder with the speculum in place and the entire anterior vagina, cervix, and/or vaginal cuff visible.
If dye is not seen immediately from a fistula, then continue filling until the patient’s comfortable capacity. If no dye is seen leaking, rarely VVF is still possible. It could be positional, in which case consider placing a gauze in the vagina and have the patient walk around for 30 minutes with dye in the bladder (empty half of the instilled dye before walking for comfort).
If there is still no dye leaking into the vagina and the patient has typical leaking, a ureterovaginal fistula must be considered. Leaking of clear urine into the vagina or cervix is diagnostic of ureteral involvement if the bladder is filled with dye.
Physical examination of a woman suspected to have obstetric fistula is conducted like all other gynecologic examinations with special attention to the presence of leakage of urine and or stool per vagina.
It is essential to ensure that the woman is comfortable.
Essentials include an examination couch with Trendelenburg capability and stirrups for lithotomy position.
Cleaning solution, gauze and cotton swabs, 12F female catheter, 60-cc Foley tip syringe, Sims speculum, methylene blue dye, or diluted gentian violet
Ureterovaginal, ureterocervical or ureterouterine fistula
Overflow urinary incontinence
Stress or urge-type urinary incontinence
For most women with obstetric fistula, the only cure is surgery.
Women diagnosed with a small or recent obstetric fistula should have a urinary catheter placed for continuous drainage and potential spontaneous healing. Often, when a catheter is placed, the urinary leakage will decrease considerably and that can be assigned that prolonged drainage might result in healing without surgery.
If no change in urinary leakage is noted in the first few days or the patient is still leaking after 2 weeks of placement, this will likely fail as a treatment measure.
If prolonged drainage is unsuccessful, then surgery should not be performed immediately after removing a catheter. We usually wait 10 to 14 days for clearance of mucus, debris, and possible bacterial colonization related to a foreign body.
IMAGING AND OTHER DIAGNOSTICS
Ultrasound to visualize kidneys, ureters, and bladder to look for hydronephrosis, hydroureter. In low-resource settings, ultrasound has been found to be helpful in the preoperative evaluation of obstetric fistula, specifically in women with prior laparotomy to exclude ureteric involvement.
Intravenous urogram and CT urogrography can be used similarly. It is tempting to employ these diagnostic modalities in all patients before surgery, but there is generally limited utility with small fistula and capacity for cystoscopy.
Cystoscopy is useful in the management of small fistula to determine the proximity to the bladder trigone and the ureteral orifices. Cystoscopy can be impossible and often unnecessary for large fistula in which the ureters can be seen clearly.
The most common staging systems are those developed by Goh (1) and Waaldijk (2). Staging systems rely on a few critical variables that have been shown to impact the outcome of surgery. Involvement of the continence mechanism of the urethra, size of the fistula, scarring of the vagina and surrounding tissues, and bladder size are key predictors of surgical success; however, no universal system is accepted nor reliable.
A detailed narrative or pictorial description of the fistula preoperatively is essential.
The most important piece of surgical equipment for vaginal fistula surgery is a fine-tipped, mid-length scissors typically reserved for plastic surgery (Figure 6.2.2). These scissors must be capable of both fine dissection and cutting through the dense scar.
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