The Bottom Line:
Successful management must take into consideration the etiology of the fistula and the health of both the rectum and the patient. Obstetrical fistulas can be treated successfully by local approaches transanally or transvaginally. Episioproctotomy may be considered if there is an associated sphincter defect. Crohn’s related fistulas usually require proctectomy if the rectum is severely involved. Local repair can be considered in instances where the rectum is relatively healthy and local sepsis has been controlled. Radiation-induced fistulas may be secondary to cancer recurrence, which must be excluded. If the patient is not a candidate for a radical resectional approach, fecal diversion alone should be performed.
Obstetrical injuries are the most common cause of rectovaginal fistulas, occurring in up to 88% of published series [1–4]. Such fistulas present either immediately postpartum from failed recognition of a fourth-degree injury or
in 7 to 10 days following an apparently normal repair.
Inflammatory bowel disease, specifically Crohn’s disease, is the second most common cause of rectovaginal fistulas.
Prior anorectal surgery is also a frequent cause of rectovaginal fistula, which can occur especially after vaginal hysterectomy.
Infections of the anorectal region may also cause rectovaginal fistulas, the majority of which are cryptoglandular in origin.
Cancers of the anorectal region may also cause fistulas, including tumors of the anal canal, rectum, and gynecologic organs.
Transanal approaches are preferred by most colorectal surgeons, whereas gynecologists generally prefer the transvaginal approach. Choice is largely based on the surgeon’s familiarity with the approach; success has been noted with both types of operations.
Transperineal approaches carry a higher risk of disability and functional impairment than do the transanal approaches; however, they have a definite role in selected instances.
For transvaginal repairs, patient preparation is similar to that for transanal repairs; however, the patient is positioned in the lithotomy position.
Transabdominal operations are best suited for those cases where the rectum is ulcerated or is stenotic over a long segment.