An emergency medical team evaluates a 34-year-old female in the emergency department who c… — USMLE Step 2 CK

An emergency medical team evaluates a 34-year-old female in the emergency department who complains of severe, unrelenting abdominal pain and bilious vomiting for the past 24 hours. The patient underwent an uncomplicated appendectomy 15 years prior. Her temperature is $38.7^\circ\text{C}$ ( $101.7^\circ\text{F}$ ), blood pressure is $88/54\text{ mmHg}$ , pulse is $124/\text{min}$ , and respiratory rate is $22/\text{min}$ . On physical examination, the abdomen is significantly distended and diffusely tender to palpation. Board-like rigidity and rebound tenderness are present across all quadrants. Bowel sounds are absent. Laboratory results demonstrate a leukocyte count of $18,500/\text{mm}^3$ and a serum lactate level of $4.8\text{ mmol/L}$ . A supine abdominal radiograph reveals multiple dilated loops of small intestine with prominent air-fluid levels and a paucity of gas in the colon. Which of the following is the most appropriate next step in the management of this patient?

Exploratory laparotomyAnswer
B
Insertion of a nasogastric tube and clinical observation
C
Computed tomography of the abdomen and pelvis with intravenous contrast
D
Administration of intravenous broad-spectrum antibiotics and serial lactate measurements
E
Diagnostic laparoscopy

Answer

Immediate surgical exploration via laparotomy is required to address complicated small bowel obstruction with impending or established bowel infarction.

The clinical presentation of severe abdominal pain, bilious vomiting, and radiologic evidence of dilated small bowel loops indicates a small bowel obstruction. The presence of fever, marked tachycardia, hypotension, severe leukocytosis, elevated lactate, and diffuse peritonitis strongly suggests bowel ischemia or strangulation. In this setting, immediate surgical intervention via exploratory laparotomy is mandated to resect necrotic bowel, restore continuity if possible, and prevent further deterioration or death.

Step-by-Step Solution

Identify the primary pathology from the clinical and radiologic presentation.

The patient has a small bowel obstruction (SBO), likely secondary to adhesions from a previous appendectomy, characterized by bilious vomiting, distension, and classic radiographic findings.

Establishing the baseline diagnosis is necessary to apply specific management algorithms.

Assess for clinical and laboratory signs of SBO complications (strangulation, ischemia, or perforation).

The patient exhibits fever, tachycardia, hypotension, severe leukocytosis, elevated serum lactate, and diffuse peritonitis (board-like rigidity, rebound tenderness).

The presence of these "red flag" features distinguishes a simple SBO from a complicated SBO.

Determine the optimal management pathway based on the presence of complications.

Definitive surgical exploration (exploratory laparotomy) is selected over conservative measures or further imaging.

Complicated SBO with hemodynamic instability and peritonitis requires immediate operative source control to resect necrotic bowel and prevent death.

Key Concept

Management of complicated small bowel obstruction (SBO) with signs of ischemia, strangulation, or peritonitis.

Question

Answer

Step-by-Step Solution

Key Concept

Common Mistakes

Topics

More questions from this topic