A 34-year-old woman is brought to the emergency department due to the sudden onset of seve… — USMLE Step 2 CK

A $34$ -year-old woman is brought to the emergency department due to the sudden onset of severe, continuous periumbilical pain that radiates to her back. The pain started $4$ hours ago and is accompanied by intractable nausea and multiple episodes of bilious vomiting. Two years ago, she underwent an uncomplicated laparoscopic Roux-en-Y gastric bypass for morbid obesity, achieving a $50$ -kg ( $110$ -lb) weight loss. Vital signs are temperature $38.3^\circ\text{C}$ ( $100.9^\circ\text{F}$ ), heart rate $124/\text{min}$ , blood pressure $88/56\text{ mm Hg}$ , and respirations $22/\text{min}$ . Physical examination reveals a slightly distended, rigid abdomen with diffuse guarding and marked rebound tenderness. Bowel sounds are absent. Laboratory studies show a leukocyte count of $18,500/\text{mm}^3$ and a serum lactate of $4.8\text{ mmol/L}$ . An upright chest radiograph shows no free air under the diaphragm. Which of the following is the most appropriate next step in management?

Immediate surgical explorationAnswer
B
Computed tomography scan of the abdomen and pelvis
C
Nasogastric tube decompression and observation
D
Upper gastrointestinal fluoroscopy with water-soluble contrast
E
Administration of broad-spectrum antibiotics and intensive care unit admission

Answer

Immediate surgical exploration

This patient presents with a classic clinical picture of a closed-loop small bowel obstruction, likely due to an internal hernia, which is a well-known complication following Roux-en-Y gastric bypass. The presence of fever, tachycardia, hypotension, lactic acidosis, and a rigid abdomen strongly indicates that the herniated bowel has become ischemic or infarcted (strangulated obstruction). In any patient presenting with an acute surgical abdomen and hemodynamic instability, the definitive and most appropriate next step is immediate surgical exploration to relieve the obstruction and resect any necrotic tissue. Delaying intervention in this scenario significantly increases mortality.

Step-by-Step Solution

Analyze the patient's presentation and surgical history.

The patient has sudden, severe abdominal pain and bilious vomiting two years after a Roux-en-Y gastric bypass, suggesting a small bowel obstruction likely due to an internal hernia.

Identifying the underlying etiology based on past surgical history is crucial for guiding management.

Evaluate vital signs, physical examination, and laboratory findings.

The patient exhibits fever, tachycardia, hypotension, abdominal rigidity, leukocytosis, and lactic acidosis, all of which indicate peritonitis and bowel ischemia.

Recognizing signs of strangulation and hemodynamic instability determines whether the patient can undergo further imaging or requires immediate surgery.

Select the most appropriate next step in management.

The correct course of action is immediate surgical exploration.

In the setting of a strangulated bowel obstruction with peritonitis, delaying surgery for any imaging or attempting conservative management is contraindicated.

Key Concept

Patients with a history of Roux-en-Y gastric bypass are at high risk for internal hernias. When these present with signs of small bowel obstruction complicated by peritonitis or hemodynamic instability, immediate surgical exploration is required.

Question

Answer

Step-by-Step Solution

Key Concept

Common Mistakes

Topics

More questions from this topic