NMS. Casos Clínicos

214 Part II ♦ Specific Disorders • Rectal cancers respond to radiation therapy, whereas colonic cancers do not. • Anal cancers respond to combination chemo and radiation therapy, which is the primary therapy. • Anal cancer and lower rectal cancers can metastasize to inguinal nodes. • Patients with clinical diverticulitis must have colon cancer ruled out after the acute event subsides. Lower Gastrointestinal Bleeding • Massive lower gastrointestinal (GI) bleed is usually secondary to diverticulosis or arteriovenous malformations of the cecum. • The site of lower GI bleeding should be confirmed before surgery.

SMALL INTESTINAL DISORDERS Critical Surgical Associations If You Hear/See Think Small bowel obstruction, previous surgery Adhesions Small bowel obstruction, hernia Surgery Closed loop obstruction

Emergent surgery

Meckel diverticulum Creeping fat on ileum

Bleed (heterotopic gastric mucosa)

Crohn disease

Crohn and obstruction, fistula, or bleed Surgery

Case 8.1 Crampy Abdominal Pain A 45-year-old has a 3-day history of nausea and crampy abdominal pain followed by vomiting and abdominal distention . The patient has had no bowel movements in the past 3 days. There are no other significant history except for a previous appen- dectomy. On physical examination, it is found that the patient has mild tachycardia and mild orthostatic hypotension. The exam is otherwise normal, except for the abdomen, which is distended, tympanitic, and mildly tender throughout but without rebound or localized tenderness . The bowel sounds have a crescendo– decrescendo quality with periods of hyperactivity and periods of silence. There is no stool in the rectum. WBC count is 14,000/mm 3 , and hematocrit is 44%. Q: What is the most likely diagnosis? A: A small bowel obstruction is the most likely possibility, although a number of other prob- lems, such as ileus, could have a similar clinical picture. SAMPLE

The next step is to obtain an abdominal radiograph.