What is the recommended treatment for an asthma exacerbation?

Treatment of Asthma Exacerbation

The first-line treatment for an asthma exacerbation is inhaled short-acting beta2-agonists (SABAs) such as albuterol administered every 20 minutes for the first hour, followed by systemic corticosteroids within the first hour for moderate to severe exacerbations. 1

Initial Management Algorithm

Step 1: SABA Administration

• Administer albuterol via one of the following methods:
  • 2-4 puffs via metered-dose inhaler with spacer every 20 minutes for up to 1 hour
  • Nebulized albuterol 2.5-5 mg every 20 minutes for up to 1 hour 1
  • For children weighing <15 kg, use albuterol inhalation solution 0.5% instead of 0.083% 2

Step 2: Systemic Corticosteroids (for moderate to severe exacerbations)

Start within the first hour of treatment:

• Adults:
  • Prednisone 40-60 mg orally OR
  • Methylprednisolone 125 mg IV 1
• Children:
  • Prednisone 1-2 mg/kg/day (maximum 60 mg) 1

Research evidence shows that oral corticosteroids are as effective as intravenous corticosteroids for treating asthma exacerbations, with no significant difference in outcomes 3, 4. Oral administration is more cost-effective and should be preferred when patients can tolerate oral medications.

Step 3: Add-on Therapies for Severe Exacerbations

• Ipratropium bromide:
  • 0.5 mg via nebulizer OR
  • 4-8 puffs via MDI every 20 minutes for the first hour
  • Then every 6 hours until improvement begins 1
• For severe exacerbations not responding to initial therapy:
  • IV magnesium sulfate 2 g infused over 20 minutes 1

Oxygen Therapy and Monitoring

• Administer oxygen through nasal cannula or mask to maintain:
  • SaO2 >90% in most patients
  • SaO2 >95% in pregnant women and patients with heart disease 1
• For severe cases:
  • Consider continuous cardiac monitoring
  • Repeat arterial blood gas measurements, especially if clinical deterioration occurs 1

Non-Invasive Ventilation (for Respiratory Failure)

• Initial BiPAP settings:
  • IPAP: 8-12 cmH2O
  • EPAP: 3-7 cmH2O
  • Target SpO2 >90% but no higher than 96% 1
• Assess response within 1-2 hours of initiation 1

Ongoing Management

• Continue oral corticosteroids for 5-7 days for moderate to severe exacerbations 1
• Short courses of systemic corticosteroids (7-10 days) have been shown to significantly reduce relapse rates and decrease beta-agonist use after discharge 5

Discharge Criteria

• FEV1 or PEF ≥70% of predicted or personal best
• Minimal or absent symptoms
• Stable response to bronchodilator therapy for 60 minutes 1

Warning Signs and Special Considerations

• Monitor closely for paradoxical bronchospasm, which can be life-threatening and requires immediate discontinuation of the current treatment 2
• Patients with a history of rapid deterioration are at higher risk of sudden death 1
• Transfer to intensive care if the patient has:
  • Deteriorating PEF despite treatment
  • Persistent or worsening hypoxia
  • Hypercapnia
  • Exhaustion, confusion, drowsiness, or respiratory arrest 1

Common Pitfalls to Avoid

1. Delaying corticosteroid administration in moderate to severe exacerbations 1
2. Underestimating severity based on clinical appearance alone 1
3. Excessive use of inhaled beta-agonists, which has been associated with fatalities 2
4. Using inhaled corticosteroids alone for acute exacerbations, which is not recommended as primary treatment 6

Remember that early administration of systemic corticosteroids is crucial in preventing relapse, with evidence showing that as few as 13 patients need to be treated to prevent one relapse to additional care after an exacerbation 5.