prior gastrointestinal surgery (e.g., vagotomy, antrectomy, pyroloplasty, gastroplasty, gastrojejunostomy) or gastrointestinal disease resulting in impaired gastrointestinal function (e.g., paralytic ileus, gastroparesis, inflammatory bowel disease, "short gut" syndrome due to adhesions or decreased transit time, past history of peritonitis, cystic fibrosis, chronic intestinal pseudobstruction, or Meckel diverticulum)