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Difficulty: HardGastrointestinal and Abdominal Surgery

A 48-year-old woman comes to the emergency department due to a 24-hour history of severe, colicky abdominal pain, nausea, and bilious vomiting. She has not passed flatus or stool since the pain began. Her medical history is notable for a laparoscopic appendectomy 10 years ago. She takes no daily medications. Her temperature is 37.3°C (99.1°F), blood pressure is 114/76 mm Hg, pulse is 106/min, and respirations are 18/min. Physical examination reveals an asymmetrically distended abdomen. It is highly tympanitic to percussion and moderately tender diffusely, but there is no guarding or rebound tenderness. Bowel sounds are high-pitched and hyperactive. A plain radiograph of the abdomen demonstrates a markedly dilated, comma-shaped loop of bowel originating in the right lower quadrant and projecting toward the left upper quadrant. There is a single air-fluid level within the loop and a paucity of gas in the distal colon. Which of the following is the most appropriate next step in management?

  1. Urgent surgical explorationAnswer
  2. B
    Endoscopic decompression via flexible sigmoidoscopy
  3. C
    Intravenous administration of neostigmine
  4. D
    Placement of a nasogastric tube and nonoperative observation
  5. E
    Administration of a water-soluble contrast enema

Answer

The most appropriate next step is urgent surgical exploration.
The correct answer outlines the definitive treatment for cecal volvulus. Cecal volvulus occurs when the cecum twists on its mesentery, creating a closed-loop obstruction. Radiographically, it appears as a large, dilated, comma- or kidney-bean-shaped loop originating in the right lower quadrant and pointing toward the epigastrium or left upper quadrant. Because it is a closed-loop obstruction, the risk of vascular compromise, ischemia, and gangrene is high. The standard of care is urgent surgical exploration, typically involving a right hemicolectomy (if ischemic) or a cecopexy (if viable), because endoscopic decompression is technically difficult, largely unsuccessful, and carries an unacceptable risk of causing colonic perforation.

Step-by-Step Solution

1
Analyze the patient's clinical presentation.
The patient exhibits classic signs of a mechanical intestinal obstruction, including colicky abdominal pain, bilious vomiting, obstipation, asymmetric distension, and high-pitched bowel sounds.
Identifying the syndrome of mechanical obstruction narrows the differential diagnosis to causes like adhesions, hernias, tumors, or volvulus.
2
Interpret the radiographic findings to identify the specific etiology.
The plain abdominal radiograph shows a markedly dilated, comma-shaped loop of bowel extending from the right lower quadrant to the left upper quadrant with distal colonic collapse.
This specific radiographic pattern (often called the 'embryo' or 'comma' sign) is pathognomonic for a cecal volvulus.
3
Differentiate the radiographic findings from other causes of massive large bowel dilation.
A sigmoid volvulus typically shows a 'coffee-bean' sign originating in the pelvis and extending toward the right upper quadrant. Ogilvie syndrome would show diffuse colonic dilation without a transition point.
Properly distinguishing cecal from sigmoid volvulus is critical because their initial management pathways differ significantly.
4
Determine the optimal management for the identified pathology.
Cecal volvulus is managed with urgent surgical exploration.
Unlike sigmoid volvulus, which can often be detorsed endoscopically, cecal volvulus rarely responds to endoscopy and has a high rate of perforation. Therefore, definitive surgical resection or cecopexy is indicated.

Key Concept

Cecal volvulus is a closed-loop mechanical obstruction diagnosed by an abdominal X-ray showing a dilated loop extending from the right lower quadrant toward the left upper quadrant. It requires urgent surgical exploration rather than endoscopic decompression.
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Topics

Gastrointestinal and Abdominal Surgery

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