A 34-year-old female is evaluated in the emergency department after experiencing the abrup… — USMLE Step 3

A $34$ -year-old female is evaluated in the emergency department after experiencing the abrupt onset of severe, cramping periumbilical pain radiating to her back $6$ hours ago. She has also had multiple episodes of bilious vomiting. Her medical history is significant for morbid obesity, for which she underwent an uncomplicated laparoscopic Roux-en-Y gastric bypass $4$ years ago. Her current body mass index is $26 \text{ kg/m}^2$ . Her temperature is $37.1^\circ\text{C}$ ( $98.8^\circ\text{F}$ ), blood pressure is $112/68 \text{ mm Hg}$ , pulse is $118/\text{min}$ , and respirations are $20/\text{min}$ . Physical examination reveals a non-distended but diffusely tender abdomen, particularly in the periumbilical region, with mild voluntary guarding. Bowel sounds are high-pitched and hyperactive. Laboratory studies show a leukocyte count of $14,200/\text{mm}^3$ and a serum lactate level of $3.1 \text{ mmol/L}$ . A computed tomography scan of the abdomen and pelvis with intravenous contrast reveals small bowel dilation with a transition point and a 'swirl sign' of the mesenteric vessels. Which of the following is the most appropriate next step in management?

A
Urgent upper gastrointestinal endoscopy
B
Nasogastric tube placement and serial abdominal examinations
C
Administration of intravenous metoclopramide
Emergent surgical explorationCevap
E
Repeat computed tomography scan of the abdomen and pelvis with oral contrast

Cevap

Emergent surgical exploration

The correct answer is emergent surgical exploration. This patient is presenting with a small bowel obstruction complicated by suspected bowel ischemia (indicated by tachycardia, leukocytosis, and an elevated serum lactate), most likely due to an internal hernia. Patients with a history of Roux-en-Y gastric bypass are at high risk for internal hernias because the surgical restructuring creates unnatural mesenteric defects (e.g., Petersen's space, mesojejunal defect) through which the small bowel can herniate. The 'swirl sign' on computed tomography imaging represents twisted mesenteric vessels and is a highly specific indicator of an internal hernia with a closed-loop obstruction. Because closed-loop obstructions rapidly progress to strangulation, irreversible ischemia, and necrosis, immediate operative intervention (diagnostic laparoscopy or exploratory laparotomy) is absolutely necessary to reduce the herniated bowel, assess its viability, and close the mesenteric defects.

Adım Adım Çözüm

Evaluate the patient's history and acute presentation.

The patient has a history of Roux-en-Y gastric bypass and presents with severe abdominal pain, bilious vomiting, tachycardia, leukocytosis, and elevated lactate.

These findings are highly suspicious for a surgical abdomen, particularly bowel ischemia.

Interpret the imaging findings in the context of her surgical history.

The CT scan shows a 'swirl sign' of the mesenteric vessels and a small bowel transition point, confirming a closed-loop obstruction due to an internal hernia.

Roux-en-Y gastric bypass creates mesenteric defects that predispose patients to internal hernias, which often present as closed-loop obstructions.

Determine the appropriate intervention.

The patient requires emergent surgical exploration.

Closed-loop obstructions with signs of ischemia (elevated lactate, leukocytosis) carry a high mortality rate if definitive surgical reduction is delayed.

Anahtar Kavram

Recognition and immediate surgical management of an internal hernia presenting as a closed-loop obstruction in a patient with a history of Roux-en-Y gastric bypass.

Soru

Cevap

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