Asthma USMLE Step 1 Practice Question
A 52-year-old obese man presents with loud snoring, witnessed apneas during sleep, and excessive daytime sleepiness. He reports morning headaches and denies asthma or reactive airway disease. Vital signs show BP 154/96 mm Hg, HR 88/min, RR 16/min, SpO2 89% during sleep. Polysomnography reveals an apnea-hypopnea index of 42 events/hour. Which of the following best explains the underlying mechanism of his nighttime breathing disorder?
Answer choices
- AFibrotic restriction of the chest wall
- BDestruction of alveolar septa causing hyperinflation
- CPharyngeal soft tissue collapse during sleep causing intermittent upper airway obstructionCorrect answer
- DRecurrent aspiration of gastric contents
- ELoss of central respiratory drive during sleep
- FExcessive mucus production and inflammation in the lower airways causing small airway obstruction
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