Gross Anatomy USMLE Step 1 Practice Question
A 1-day-old boy presents with severe respiratory distress, tachypnea (RR 62/min), and tachycardia (HR 168/min). Physical examination reveals a scaphoid abdomen and diminished breath sounds on the left. Chest radiography demonstrates bowel loops in the left hemithorax with mediastinal shift. Arterial blood gas shows hypoxemia (SpO2 88%). There is no cyanosis with supplemental oxygen. Failure of which embryologic structure most likely caused this congenital diaphragmatic hernia?
Answer choices
- ALaryngotracheal diverticulum
- BDorsal mesentery of esophagus
- CPleuroperitoneal membranesCorrect answer
- DSeptum transversum
- EBody wall musculature
- FPleuropericardial membranes
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