A 76-year-old woman is brought to the emergency department due to sudden-onset, severe abd… — USMLE Step 2 CK

A $76$ -year-old woman is brought to the emergency department due to sudden-onset, severe abdominal pain that started $4$ hours ago. She has a medical history of hypertension, hyperlipidemia, type 2 diabetes mellitus, and paroxysmal atrial fibrillation. She was prescribed apixaban but admits to missing several doses over the past week. The patient also reports one episode of bilious vomiting at home. On arrival, her temperature is $38.4^\circ\text{C}$ ( $101.1^\circ\text{F}$ ), blood pressure is $88/56\text{ mm Hg}$ , and pulse is $122/\text{min}$ and irregularly irregular. Physical examination reveals a moderately distended abdomen with diffuse rigidity, involuntary guarding, and rebound tenderness. Bowel sounds are absent. Laboratory studies demonstrate a leukocyte count of $21,000/\text{mm}^3$ and a serum lactate level of $5.8\text{ mmol/L}$ (normal: $0.5-1.0\text{ mmol/L}$ ). Which of the following is the most appropriate next step in the management of this patient?

Emergency exploratory laparotomyCevap
B
CT angiography of the abdomen
C
Nasogastric tube decompression and serial abdominal examinations
D
Intravenous piperacillin-tazobactam and admission to the intensive care unit
E
Measurement of arterial blood gases to calculate expected respiratory compensation

Cevap

Emergency exploratory laparotomy

The correct answer is emergency exploratory laparotomy. This patient's presentation of sudden-onset, severe abdominal pain in the setting of atrial fibrillation and missed anticoagulant doses is highly suspicious for acute mesenteric ischemia due to an arterial embolus (typically lodging in the superior mesenteric artery). While the classic early presentation involves 'pain out of proportion to physical exam findings,' this patient now demonstrates hemodynamic instability (hypotension, tachycardia) and frank peritonitis (rigid abdomen, involuntary guarding, rebound tenderness), accompanied by significantly elevated serum lactate. These clinical findings indicate that transmural bowel infarction and potential perforation have already occurred. In any patient with suspected acute mesenteric ischemia who develops peritonitis or hemodynamic instability, immediate surgical exploration (laparotomy) is required to resect necrotic bowel and restore perfusion. Delaying surgery to obtain confirmatory imaging or attempt medical management in this scenario significantly increases the risk of mortality.

Adım Adım Çözüm

Identify the primary clinical syndrome based on the patient's history and acute presentation.

The patient has sudden-onset, severe abdominal pain with a history of paroxysmal atrial fibrillation and anticoagulant non-compliance, which is highly indicative of acute mesenteric ischemia due to an arterial embolus.

Recognizing the risk factors (atrial fibrillation) and classic symptom onset is the first step in formulating an accurate differential diagnosis.

Evaluate the patient's hemodynamic status and physical examination findings.

The patient is hemodynamically unstable (blood pressure

88/56\text{ mm Hg}

) and exhibits clear signs of peritonitis (diffuse rigidity, involuntary guarding, rebound tenderness).

Physical exam findings and vital signs are critical for determining whether the patient can safely undergo further diagnostic imaging or requires immediate surgical intervention.

Determine the most appropriate next step in management based on the presence of peritonitis and instability.

The presence of peritonitis and hemodynamic instability in suspected acute mesenteric ischemia mandates immediate emergency exploratory laparotomy.

Peritonitis indicates that transmural bowel infarction and potential perforation have already occurred. Delaying surgery for any reason significantly increases mortality.

Anahtar Kavram

Patients with suspected acute mesenteric ischemia who develop signs of peritonitis or hemodynamic instability require immediate emergency exploratory laparotomy to resect necrotic bowel.

Soru

Cevap

Adım Adım Çözüm

Anahtar Kavram

Sık Yapılan Hatalar

Konular

Bu konudan daha fazla soru