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Life-threatening acute asthma — SCE Acute Medicine MCQ

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HardRespiratory medicineLife-threatening acute asthmaSCE Acute Medicine

A 44-year-old man with known asthma presents after two hours of worsening wheeze. He is unable to complete sentences, RR 34/min and pulse 124/min. SpO2 is 92% on 15 L/min oxygen. PEF is 28% predicted, and ABG shows pH 7.37, PaCO2 5.6 kPa and PaO2 10.1 kPa on high-flow oxygen. What is the most appropriate next step in management?

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Correct answer: D — Continue high-flow oxygen, repeated nebulised bronchodilators, systemic steroids and urgent critical care review

A normal or rising PaCO2 in a severe asthma attack is a marker of life-threatening asthma because patients should usually be hypocapnic. The appropriate response is aggressive bronchodilator therapy, steroids, oxygen and urgent senior/critical care involvement. Controlled 88–92% oxygen is for patients at risk of hypercapnic respiratory failure, not acute asthma.

Reference: BTS/SIGN Asthma Guideline 2024/2025; BTS Oxygen Guideline