A morbidly obese patient is undergoing a total abdominal colectomy for fulminant colitis. He is receiving high-dose steroids and biologic therapy, and he has been preoperatively marked by an enterostomal therapist. The ileal mesentery is foreshortened, and the abdominal wall is thick. You are unable to bring the divided end of the ileum to the skin without tearing the mesentery. What is the best next step in management?