Asthma USMLE Step 1 Practice Question
A 6-year-old boy presents with acute asthma exacerbation. Vitals: HR 128/min, RR 32/min, BP 105/68 mmHg, SpO₂ 89% on supplemental oxygen, temperature 37.2°C. He receives continuous nebulized albuterol and IV methylprednisolone. After 2 hours, peak expiratory flow remains 50% of predicted with persistent diffuse wheezing. Chest X-ray shows hyperinflation without pneumothorax. He denies chest pain. Which intervention is most appropriate?
Answer choices
- AAdd IV magnesium sulfateCorrect answer
- BDiscontinue corticosteroids to avoid immunosuppression
- CSwitch to ipratropium bromide as monotherapy
- DAdminister systemic antibiotics for presumed infection
- EIntubate immediately without further medication trials
- FSubcutaneous terbutaline for systemic beta-2 agonism
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