NMS. Casos Clínicos

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Part II ♦ Specific Disorders

Figure 8-11: Toxic megacolon. A: Supine radiograph of the abdomen demonstrates marked dilation of the colon with the cecum measuring 14 cm (red arrow) and the descending colon measuring 7 cm (white arrows) in diameter. The mucosal pattern of the lower descending colon is strikingly nodular (arrowhead). B: Corresponding CT showed marked thickening of the wall of the colon (arrow). Toxic megacolon was related to ulcerative colitis. The colon perforated just prior to surgery. (From Klein J, Brant WE, Helms CA, Vinson EN. Brant and Helms’ Fundamentals of Diagnostic Radiology , 5th ed. Wolters Kluwer Health; 2018, Fig. 40-19.)

Q: What is the initial evaluation? A: Routine blood studies and an abdominal obstructive series to rule out bowel perforation are necessary. Many physicians would also perform CT of the abdomen to be certain that there is no abdominal process such as an abscess or perforation. A typical appearance on abdominal radiography usually establishes the diagnosis ( Fig. 8-11 ). Sigmoidoscopy may also be helpful but should be performed cautiously. The patient’s radiographs show a very dilated colon with mucosal edema and no signs of abscess or perforation. Q: How would you initially manage this patient? A: Provided that the patient is stable, a trial of medical therapy is indicated. Treatment consists of placement of an NG tube, NPO feeding, TPN, and IV fluids and broad-spec- trum antibiotics. Most physicians would also use high-dose IV steroids . The acute prob- lem resolves in 50% or more patients with this therapy. Close observation for worsening signs and symptoms , with frequent abdominal examinations and radiographs, is neces- sary because the mortality of patients who have a bowel perforation from toxic megacolon ranges from 27% to 44%. SAMPLE Q: How would you manage the following findings? Case Variation 8.12.1. Free air on upright CXR

◆ ◆ The patient should be taken immediately to the operating room; this is evidence of perfo- ration. The mortality rate is extremely high when perforation has occurred. The procedure