Repair of Rectovaginal Fistulas
Most rectovaginal fistulas seen by the obstetrician/gynecologist are secondary to obstetric injury. These fistulas are usually in the distal third of the vagina. The key to successful repair of a rectovaginal fistula is excision of the fistulous tract with tension-free approximation of the edges of the defect. There should be excellent hemostasis, and perioperative antibiotics should be administered to decrease any potential for infection.
Most fistulas are easily visualized and can be palpated on rectovaginal examination. At times, the passage of a probe helps delineate the fistula and its tract (Fig. 99–1).
Following is a description of a repair of a primary nonirradiated rectovaginal fistula:
1. The surgeon’s nondominant index finger is placed in the rectum to aid in identification of the fistula and to assess the extent of scarification. A rectal finger will also facilitate dissection in the appropriate plane.
2. The initial incision depends on the anatomic location of the fistula. Many fistulas are best approached with an inverted-U perineal incision (Fig. 99–2). This allows easy mobilization of the posterior vaginal wall from the anterior rectal wall, as well as rebuilding of the perineal body. If the external anal sphincter is intact, there is no reason to disrupt it. If the fistula is higher in the vagina and the perineum is intact, an incision can be made directly into the posterior vaginal wall over and around the fistula.
3. With traction of the vaginal wall and a finger in the rectum to provide support of the rectal wall, sharp dissection is used to widely mobilize the posterior vaginal wall from the anterior rectal wall (Figs. 99–3 and 99–4).
4. Once the vaginal walls are widely mobilized from the underlying rectum, the entire fistulous tract is excised. After the scar tissue is removed, the defect in the anterior rectal wall will enlarge. The rectal wall is cut back until fresh edges are encountered (see Fig. 99–4).
5. With the surgeon’s index finger elevating the anterior rectal wall, an initial row of 3-0 or 4-0 absorbable sutures is placed (Fig. 99–5
