What are the causes and management of acute asthma exacerbation (Acute Asthmatic Attack)?

From the Guidelines

Asthma exacerbation requires prompt treatment with short-acting beta-agonists (SABAs) like albuterol and oral corticosteroids, with supplemental oxygen to maintain oxygen saturation ≥92%, as the most effective approach for resolving symptoms and preventing relapse. The management of acute asthma exacerbation involves several key components, including:

• Immediate treatment with SABAs, such as albuterol, via metered-dose inhaler with spacer or nebulizer, as first-line therapy 1
• Early initiation of oral corticosteroids, typically prednisone 40-60 mg daily for 5-7 days for adults (1-2 mg/kg/day for children, maximum 60 mg), to reduce inflammation 1
• Supplemental oxygen to maintain oxygen saturation ≥92% 1
• Consideration of adding ipratropium bromide and intravenous magnesium sulfate for severe exacerbations not responding to initial treatment 1
• Monitoring of lung function, oxygen saturation, and clinical symptoms to guide treatment and adjust as needed 1

The causes of acute asthma exacerbation include airway inflammation, bronchoconstriction, and mucus hypersecretion, which can be triggered by various factors such as allergens, respiratory infections, and environmental irritants. SABAs provide immediate bronchodilation by relaxing airway smooth muscle, while corticosteroids reduce inflammation, making this combination approach most effective for resolving symptoms and preventing relapse 1.

In severe cases, consultation with or comanagement by a physician expert in ventilator management may be necessary, and intubation should be done semielectively and before respiratory arrest occurs 1. The recommended ventilator strategy is "permissive hypercapnia" or "controlled hypoventilation," which provides adequate oxygenation while minimizing airway pressures and the possibility of barotrauma 1.

After stabilization, patients should continue albuterol every 4-6 hours as needed and complete the corticosteroid course, with a written asthma action plan, review of inhaler technique, and follow-up appointment within 1-2 weeks being essential for preventing future exacerbations and improving quality of life 1.

From the Research

Causes of Acute Asthma Exacerbation

• Asthma exacerbations can be caused by a variety of factors, including respiratory infections, allergens, and air pollutants 2
• A broad differential diagnosis should be considered when evaluating a patient with a potential asthma exacerbation 2

Management of Acute Asthma Exacerbation

• First-line therapies for severe exacerbations include:
  • Inhaled short-acting beta agonists (e.g. albuterol) 2, 3, 4
  • Inhaled anticholinergics (e.g. ipratropium bromide) 2, 5, 4
  • Intravenous steroids 2
  • Magnesium sulfate 2, 4
• Additional therapies for refractory cases include:
  • Parenteral epinephrine or terbutaline 2
  • Helium-oxygen mixture 2
  • Ketamine 2, 4
• Noninvasive positive pressure ventilation may be used to prevent the need for endotracheal intubation 2, 4
• Patients with severe asthma exacerbations will require intensive care unit admission 2

Treatment of Acute Asthma in Children

• The combination of inhaled short-acting beta2-agonists and anticholinergics is effective in reducing hospital admissions in children with moderate to severe asthma exacerbations 5
• However, in children hospitalized for an acute asthma exacerbation, the addition of anticholinergics to short-acting beta2-agonists shows no evidence of benefit for length of hospital stay and other markers of response to therapy 6

Medication Administration

• Handheld inhalers are sufficient for most inhaled therapy, and all patients on inhalers should be provided with a spacer 4
• Levalbuterol provides little to no advantage over less-expensive racemic albuterol 4