RESUMEN
PURPOSE: This report presents the technique and results of transanal one-stage endorectal pull-through procedure in children with rectosigmoid lesions from Hirschsprung's disease. METHODS: Eight children aged one month to 6 years with frozen section biopsy-proven Hirschsprung's disease underwent transanal one-stage endorectal pull-through procedures during a 12-month period. A rectosigmoid transitional zone was suggested by contrast enema in 7 patients; rectal manometry was done to confirm the diagnosis in one patient. Preoperative colonic irrigation to evacuate feces out of the dilated colon was done in the hospital. Bowel preparation was the same as conventional colorectal surgery. Full-thickness rectal biopsy at 1 to 2 cm above the dentate line was submitted for pathologic diagnosis. A rectal mucosectomy dissection was started 0.5 cm proximal to the dentate lines and was extended into the intraperitoneal rectum. The muscular sleeve was divided circumferentialy at 3 to 4 cm proximal to the dentate line, exposing the intraperitoneal rectum and allowing full-thickness mobilization of the rectosigmoid colon out of the anus. Aganglionic colon segment was resected, and the normal colon was pull down to anastomose with the distal end of anorectal mucosa. RESULTS: Operating time, including taking frozen sections, ranged from 110 to 180 minutes. The length of bowel resections ranged from 9 to 25 cm. The length of hospital stay depended on the amount of fecal impaction in the colon. Older children with substantial fecal impaction required 2 weeks of preoperative saline enema. One infant needed 3 days for bowel preparation, the same as for conventional colorectal surgery. The hospital stay ranged from 6 to 7 days in children younger than 2 years and 10 to 28 days in older children. There were no intraoperative or postoperative complications related to the pull-through procedure. One case of colitis occurred in the 6-year-old child, which required rectal tube decompression one week after the operation. Seven patients passed stool within 24 hours after surgery. All patients had normal bowel movements within 3 weeks. There was no rectal cuff stricture or enterocolitis during one year of follow-up. CONCLUSIONS: Transanal one-stage endorectal pull-through operations for rectosigmoid lesions from Hirschsprung's disease can be performed successfully in all ages of children with good results, avoiding transabdominal exploration. The early postoperative enterocolitis in the older children might occur and should be treated urgently. The partial coloanal anastomosis obstruction found in older children could be treated by placing a rectal tube into the anus to decompress the dilated pull-through colon. The limitation of this approach is that retroperitoneal fixation of the descending colon could not be dissected by the transanal route.