Preoperative Preparation and Planning
Rectourinary (rectovesical or rectourethral) fistulas typically occur as a result of iatrogenic causes such as prior radiation or operative injury. They may also occur from congenital anomalies, infection, or malignancy. Rectourinary fistulas commonly present with fecaluria, pneumaturia, urinary tract infection, urinary drainage per rectum, fever, and/or pelvic abscess. Often, the fistula is grossly palpable on digital rectal examination. Cystourethroscopy, colonoscopy, and/or retrograde urethrography can aid in diagnosis and operative planning ( Fig. 96.1 ).
Frequently, bowel diversion with either a loop colostomy or ileostomy is recommended on initial diagnosis, though recent studies have shown this may not always be necessary. A suprapubic tube may be placed for temporary urinary diversion as well. All patients should receive a vigorous preoperative antibiotic and mechanical bowel regimen.
Although it has been shown that spontaneous closure of small, nonradiated, iatrogenic rectourinary fistulas can occur, surgical correction is often necessary. While there are several approaches for rectourinary fistula repair, the York–Mason procedure continues to show durable and favorable results. As such, the timing of the surgical repair is paramount. Although many iatrogenic, nonradiated fistulas may be repaired immediately, surgical reconstruction of radiation-induced fistulas should be delayed at least 6 months, and patients should be counseled appropriately. In cases of malignancy, an eroding infectious process, or large, radiation-induced fistulas, operative closure is not indicated and formal urinary diversion should be performed.
Operative Technique
After general anesthesia is administered, a Foley catheter is inserted. Initial cystoscopic placement of a guidewire through the fistula and into the rectal lumen can be helpful for fistula identification. The patient is then placed on the operating table in a prone jackknife position. Care should be taken to pad all pressure points appropriately. The patient should be prepared in the standard sterile fashion. Adhesive tape can be used to separate the buttocks. An incision is made in the midline from the tip of the coccyx to the anal verge ( Fig. 96.2 ). The anal sphincter is then incised sharply. Prior to separating the muscular layers of the sphincter, each layer should be tagged with matching sutures on either side of the incision. This will aid in identifying the sphincter layers at closure. The posterior anus and rectum are then opened along the full length of the incision. Retractors are placed to separate the incision and allow vision of the anterior rectal wall. Usually, the fistula site is evident on gross inspection, and the Foley catheter can be visualized. The fistula tract and the surrounding inflammatory tissue are then excised.