Endorectal ileal pullthrough procedure after chemical debridement of the rectal mucosa

The technical difficulty of removing the intact rectal mucosa without damaging the rectal muscularis and anorectal sphincter mechanism when there is extensive inflammation has prompted evaluation of techniques other than direct surgical stripping. The present study was done to evaluate the histopathologic effectiveness of chemical debridement of the rectal mucosa in dogs with 0.5 N sodium hydroxide solution and 1 per cent acetic acid. Repeated exposure of the mucosa to sodium hydroxide solution on three consecutive days produced a second degree burn of the mucosa leading to sloughing without appreciably injuring the underlying muscularis. Minimal inflammation or hemorrhage was observed four and eight weeks after removal of the rectal mucosa and endorectal ileal pullthrough using both light and scanning electron microscopy. Excellent healing occurred between the ileal pullthrough segment and the rectal muscularis without evidence of abscess. Anorectal manometric studies showed minor changes in a comparison of the preoperative and four week postoperative tractings. Chemical debridement of the rectal mucosa appears to be a helpful adjunct to mechanical stripping in situations in which the mucosa is extensively inflamed or tenaciously adherent to the muscularis, or both, when endorectal ileal pullthrough is the desired operation.