This patient had a colostomy placed 9 days ago after resection of colonic carcinoma. Earlier today, he felt nauseated and stated that his colostomy stopped filling. He also had a sensation of "heartburn." He denies vomiting but has been nauseated. He denies diarrhea. He denies hematochezia, hematemesis, or melena. He denies frank abdominal pain or fever.