An external conduit (stoma) for patients with biliary atresia has been used to prevent postoperative cholangitis. Thirty-two patients with biliary atresia who had hepatic portoenterostomies with external conduits were studied retrospectively with respect to frequency and severity of postoperative cholangitis or stoma bleeding. Changes in their liver enzyme levels, and total bilirubin (TB) levels were measured before and after closure of the stoma. Cholangitis was observed in 20 patients (62.5%), and major hemorrhage from the stoma site was seen in 14 patients (43.8%) prior to closure. Levels of liver enzymes such as glutamic oxaloacetic transaminase (SGOT), glutamic pyruvic transaminase (SGPT), gamma-glutamyl transpeptidase (gamma-GTP), and alkaline phosphatase (ALP) improved significantly within 1 month after closure of the stoma, and remained low thereafter. The TB concentration was the only liver function that did not change significantly following closure. In summary, the authors do not recommend an external conduit in patients with biliary atresia because it is not an effective way of reducing the incidence of postoperative cholangitis, and it may be deleterious to liver function.