Gross Anatomy USMLE Step 1 Practice Question
A 47-year-old man undergoes left subclavian central venous catheter placement. Within 24 hours, he develops dyspnea, with vital signs showing HR 102/min, RR 22/min, and SpO2 92% on room air. Chest X-ray reveals left-sided pleural effusion. Thoracentesis yields milky fluid with triglycerides of 450 mg/dL. Temperature is 37.2°C and breath sounds are present bilaterally. Which of the following structures was most likely injured during catheter placement?
Answer choices
- ALeft phrenic nerve
- BRight lymphatic duct
- CVagus nerve
- DAzygos vein
- EThoracic ductCorrect answer
- FLeft internal jugular vein
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