NMS. Casos Clínicos

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Chapter 8 ♦ Lower Gastrointestinal Disorders

Q: How would you evaluate this patient? A: Hydration is necessary. Electrolytes, a CBC, and an abdominal obstructive radiographic series to rule out obstruction or other abdominal pathology are also warranted.

Q: How would you evaluate the following radiologic findings? Case Variation 8.35.1. Sigmoid volvulus

◆ ◆ A sigmoid volvulus occurs most commonly in debilitated patients from nursing homes, often as a result of chronic laxative use, chronic illness, or dementia. Sigmoid volvulus de- velops from a clockwise twist of mobile sigmoid colon around the mesentery, leading to a closed loop obstruction. A contrast enema can be used to confirm the volvulus if necessary. ◆ ◆ Definitive therapy is usually planned during the same hospital stay. The treatment is ei- ther sigmoid colectomy with diverting colostomy or resection with primary anastomosis, depending on the preoperative condition of the patient. Figure 8-41 shows detorsion of volvulus and volvulus of the sigmoid colon (Fig. 8-42). If endoscopic management is unsuc- cessful, urgent laparotomy is required. The recurrence rate is approximately 30%. ◆ ◆ In stable patients with no peritonitis or signs of sepsis, it is often possible to “detorse” the sigmoid colon by rigid proctosigmoidoscopy and placement of a rectal tube. Case Variation 8.35.2. Cecal volvulus ◆ ◆ Most patients with cecal volvulus require urgent surgical treatment. Figure 8-42 shows types of torsion with cecal volvulus and cecal volvulus on radiograph. Attempts at detor- sion with a barium enema or colonoscopy are usually not successful. Surgical options in- clude detorsion alone, cecopexy, or right colectomy. In stable patients with viable bowel, the operation of choice is right colectomy with primary anastomosis. Case Variation 8.35.3. Massively dilated right colon to the level of the mid-transverse colon with distal colonic decompression ◆ ◆ Acute pseudo-obstruction, or Ogilvie syndrome , is defined as acute massive dilation of the cecum and right colon without evidence of mechanical obstruction . This commonly occurs in hospitalized patients in the intensive care unit who are intubated and seriously ill. The cecum preferentially dilates more than the remaining colon because of Laplace law. Conservative, nonoperative treatment is indicated when the cecal diameter is less than 9–10 cm. Serial radiographic films to follow colonic diameter are necessary. ◆ ◆ Many surgeons would perform decompression of immunosuppressed patients with Ogilvie syndrome when the colon diameter is smaller. ◆ ◆ If the colon diameter exceeds 11–12 cm, endoscopic decompression is indicated. Many surgeons also attempt a brief trial of neostigmine, a para- sympatholytic agent, which may increase colonic tone and counteract the dilation. If the neostigmine is unsuccessful, surgical decompression of the cecum or a right colectomy is necessary (Fig. 8-43). Case Variation 8.35.4. Entire colon packed with stool ◆ ◆ This finding is indicative of constipation, with stool seen throughout the colon. A rectal examination to ensure that the stool is not impacted is necessary. Once the stool is cleared from the vault, enemas may be performed. Severe constipation causing obstruction should always be treated from below before any cathartics are administered by mouth. SAMPLE