Acute Asthma Exacerbation Management
A 21-year-old man with recurrent exertional wheeze and cough presents 30 minutes after an aerobics class with worsening breathlessness. He speaks in short phrases; respiratory rate is 26 breaths/min, heart rate 108 beats/min and oxygen saturation 94% on room air. There are diffuse expiratory wheezes with prolonged expiration. Peak expiratory flow is 55% of predicted. Which of the following is the most effective initial emergency department treatment?
- A.Intravenous hydrocortisone
- B.Nebulized salbutamolCorrect
- C.Inhaled salmeterol
- D.Inhaled fluticasone
Explanation
This is a moderate acute asthma exacerbation, and the immediate priority is rapid reversal of bronchospasm with a short-acting beta-2 agonist, given by nebulizer or by metered-dose inhaler with a spacer, repeated every 20 minutes in the first hour as needed. Salbutamol stimulates beta-2 receptors on airway smooth muscle, raising intracellular cyclic AMP and producing bronchodilation within minutes, which is why it relieves airflow obstruction faster than any other available agent. Systemic corticosteroids are an essential part of treatment and should be given early, usually as oral prednisolone 40 to 50 mg, because they reduce relapse and hospital admission, but their anti-inflammatory effect takes 4 to 6 hours to appear and so they do not provide the immediate relief the question asks about; the intravenous route is reserved for patients unable to swallow or with impending respiratory failure. Salmeterol is a long-acting beta-2 agonist with a slow onset and is a controller medication, never a rescue treatment in acute severe asthma. Inhaled fluticasone is a controller corticosteroid whose onset is far too slow for an acute attack. Ipratropium bromide is added to salbutamol in severe exacerbations, and magnesium sulfate intravenously is considered when there is a poor response or life-threatening features. Warning signs of life-threatening asthma include a silent chest, exhaustion, cyanosis, bradycardia, altered consciousness and a normal or rising arterial carbon dioxide tension, all of which demand critical care involvement.
Why each option
- A.
- Systemic corticosteroids are essential but take hours to act, and the oral route is as effective as intravenous in patients who can swallow.
- B.
- Correct. An inhaled or nebulized short-acting beta-2 agonist provides bronchodilation within minutes and is the immediate treatment of an acute exacerbation.
- C.
- Salmeterol is a long-acting controller with slow onset and must never be used as rescue therapy.
- D.
- Inhaled fluticasone is a maintenance anti-inflammatory drug with no immediate bronchodilator effect.
Reference: Global Initiative for Asthma (GINA) Report, 2025
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