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Difficulty: HardGastrointestinal and Abdominal Surgery

A 72-year-old woman is brought to the emergency department due to severe, worsening abdominal pain, nausea, and bilious vomiting for the past 2 days. She has not had a bowel movement or passed flatus for 48 hours. Her medical history is significant for an open total abdominal hysterectomy 15 years ago. Her temperature is 38.6°C (101.5°F), pulse is 118/min, respirations are 22/min, and blood pressure is 96/60 mm Hg. Physical examination reveals a distended abdomen with absent bowel sounds. There is severe, diffuse abdominal tenderness with guarding and rebound tenderness. Laboratory studies show:

Leukocyte count: 18,500/mm³
Lactate: 4.2 mmol/L
Bicarbonate: 14 mEq/L

An upright abdominal radiograph reveals multiple dilated loops of small bowel with air-fluid levels and a paucity of gas in the colon. No pneumoperitoneum is observed. Which of the following is the most appropriate next step in the management of this patient?

  1. Exploratory laparotomyAnswer
  2. B
    Insertion of a nasogastric tube and serial abdominal examinations
  3. C
    Computed tomography scan of the abdomen and pelvis with intravenous contrast
  4. D
    Intravenous administration of broad-spectrum antibiotics and observation
  5. E
    Upper gastrointestinal series with small bowel follow-through

Answer

Exploratory laparotomy
The patient's presentation of bilious vomiting, obstipation, a history of abdominal surgery, and air-fluid levels on radiography confirms a small bowel obstruction. The critical decision-making step involves recognizing the signs of strangulation (ischemia): fever, significant tachycardia, severe focal or diffuse peritonitis (guarding, rebound tenderness), leukocytosis, and an elevated lactate level. When an SBO is complicated by signs of ischemia or an acute abdomen, the correct management is an immediate exploratory laparotomy. Delaying definitive surgical treatment for further imaging or an observation trial of nasogastric decompression allows ischemic bowel to progress to necrosis and perforation.

Step-by-Step Solution

1
Identify the primary diagnosis based on the clinical presentation and radiographic findings.
The patient has a small bowel obstruction (SBO), likely secondary to adhesions from a prior open hysterectomy.
Bilious vomiting, obstipation, abdominal distention, and air-fluid levels on X-ray are classic diagnostic features of an SBO.
2
Assess for clinical and laboratory signs of complications, specifically bowel ischemia or strangulation.
The patient exhibits fever, tachycardia, peritonitis (guarding and rebound tenderness), leukocytosis, and lactic acidosis.
These findings are critical indicators that the affected bowel segment has compromised perfusion and is progressing toward necrosis.
3
Determine the appropriate management pathway based on the presence of complications.
Immediate surgical intervention is indicated.
Uncomplicated SBO is managed with bowel rest and nasogastric decompression. However, the presence of an acute surgical abdomen (peritonitis) combined with signs of systemic toxicity mandates emergent exploratory laparotomy to prevent perforation.

Key Concept

Patients with small bowel obstruction who develop signs of strangulation or ischemia (fever, peritonitis, tachycardia, leukocytosis, elevated lactate) require immediate exploratory laparotomy, overriding the need for further diagnostic imaging.
Estimated Time:1m 30s
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Topics

Gastrointestinal and Abdominal Surgery

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