IPEG 2020 TOP ABSTRACT: Primary rectourethral fistula repair in a 17 year old male

Congenital rectal urethral fistula is a well-recognized type of anal rectal malformation. Patients with this pathology generally undergo repair in the infant period, although repair is sometimes delayed into early childhood due to associated comorbidities or social situations. We recently encountered a 17 year old male patient with an unrepaired rectal urethral fistula. The considerations for operative repair for this patient are somewhat different from repair in an infant or a child, and we share our experience here. This patient was found to have imperforate anus at birth, and diverting colostomy and mucous fistula were performed on day of life. He has significant additional congenital malformations including left pulmonary artery sling and tracheal stenosis, which was persistent and progressive despite attempted repair. He had frequent urinary tract infections and often leaked urine out of his mucous fistula, but due to his tracheal stenosis, he was deemed too high risk of repair for his fistula. He presented to our hospital system for care of his tracheal stenosis as he was having ongoing respiratory symptoms including biphasic stridor, frequent respiratory infections, and exertional dyspnea, for which he ultimately underwent reduce sternotomy and segmental tracheal resection. His recovery was complicated by recurrence of his tracheal stenosis, but with continued tracheal bronchial dilations, he remained stable with improvement in his respiratory symptoms. With his airway improved, attention was turned to his urologic system. In an effort to eliminate the ongoing risk to his urologic system, we planned for a takedown of his rectal urethral fistula and anorectoplasty. Based on preoperative VCUG, the distance between his anal dimple and the fistula was estimated to be 3 to 4 centimeters. Because of the amount of rectal mobilization that was anticipated, we decided to proceed with a combined abdominal and perineal approach, utilizing robotic assistance for dissection of the deep pelvic structures. The patient was prepped and draped in low lithotomy position. The procedure started with cystoscopy, which demonstrated a broad-based low prostatic rectourethral fistula. A Foley catheter was placed for bladder decompression. After initially gaining umbilical access, 3 other 8 millimeter robotic trochars were placed in the left midabdomen, right midabdomen, and right laterally, all in line with the umbilicus. The rectosigmoid was retracted out of the pelvis, and the mesor rectum was controlled with sequential fires of the robotic vessel sealer, staying close to the rectum. The mesorectal plane was followed past the peritoneal reflection into the pelvis. This plane was followed until the rectum narrowed as it approached the prostate. The Foley catheter was removed at this point and cystoscopy repeated to confirm that we had reached the rector urethral fistula. The robot system contains an integrated camera intended to be utilized with a fluorescent dye. Utilizing this camera in the absence of dye usually demonstrates a gray scale image with little useful information. But we found it helpful in identifying the light from the end of the cystoscope from the abdominal view, helping confirm the location of the fistula. Identifying the base of the fistula cystoscopically demonstrated that there was an additional 1 to 2 centimeters of fistula between the base and what we were viewing intraabdominally. We continued the rectal dissection and took down the common wall between rectum and prostatic urethra sharply with scissors so that we would avoid leaving a posterior urethral diverticulum. Dividing the fistula demonstrated the Foley catheter and a small rim of healthy tissue that was transected to keep the tissue flush with the urethra. The fistula was closed in two layers using running viral suture. The urethra was filled with saline and no leak was seen. At this point, the sphincter complex was stimulated and a small posterior sagittal incision was made and deepened through the sphincter complex to the pelvic floor. The floor was opened and dilated to a size 24 hagar. The rectum was pulled into the perineal incision and required a small amount of proximal mesenteric release to bring it down without tension. It was pulled through and the anal ectoplasty was completed in the usual fashion and easily accommodated to 22 Hagar dilator when complete. The patient tolerated the procedure well and was extubated postoperatively and weaned quickly to room air. He was observed overnight in the ICU and transferred to the surgical floor the following day. His Foley catheter will be left in place for 2 weeks to protect his urethral repair. In conclusion, it is clear that primary repair of rectal urethral fistula is quite different in adult-sized patients than it is in a child, although the basic principles remain the same. We find that the robotic system was very helpful for deep pelvic dissection. The intramural fistula length was longer than anticipated, highlighting the need for concomitant visual assessment of the urinary tract. To that end, the fluorescence camera can be helpful in visualizing the location of the cystoscope from the abdominal viewpoint. And lastly, performing the anoplasty and lithotomy position is challenging, but eliminates the need to change to prone positioning for perineal work, which is helpful in this adult-sized patient.