Management of Acute Asthma Exacerbation
Initial Assessment and Treatment
- The American Thoracic Society recommends immediately administering high-flow oxygen to maintain SaO₂ >90% (>95% in pregnant patients or those with heart disease), nebulized albuterol 2.5-5 mg every 20 minutes for 3 doses, and oral prednisolone 40-60 mg or IV hydrocortisone 200 mg within the first hour of presentation 1, 2
- Assess severity immediately using objective measurements, such as peak expiratory flow (PEF) and forced expiratory volume (FEV₁), as failure to do so is a common cause of preventable asthma deaths 3
- Severe exacerbation features include inability to complete sentences in one breath, respiratory rate >25 breaths/min, heart rate >110 beats/min, and PEF <50% of predicted or personal best 3, 1, 4
Oxygen Therapy and Bronchodilator Treatment
- Administer high-flow oxygen at 40-60% immediately via face mask or nasal cannula to maintain SaO₂ >90% (>95% in pregnant patients or those with cardiac disease) 3, 5, 1
- Administer albuterol 2.5-5 mg via nebulizer or 4-8 puffs via MDI with spacer every 20 minutes for 3 doses 1, 2
- Add ipratropium bromide 0.5 mg to nebulizer or 8 puffs via MDI every 20 minutes for 3 doses for all moderate-to-severe exacerbations 1, 2
Systemic Corticosteroids and Adjunctive Therapy
- Administer prednisolone 30-60 mg orally or hydrocortisone 200 mg IV immediately 3, 5, 1
- Consider continuous nebulization of albuterol for severe exacerbations with FEV₁ or PEF <40% predicted 4, 2
- Administer IV magnesium sulfate 2 g over 20 minutes for life-threatening features or severe exacerbations not responding after 1 hour of intensive treatment 1, 2
Monitoring and Discharge Criteria
- Repeat PEF measurement 15-30 minutes after starting treatment 5, 1
- Continue oxygen and steroids until clear response to bronchodilator therapy 3, 5, 1
- Discharge patients when PEF >75% of predicted or personal best, symptoms are minimal or absent, and patient is stable for 30-60 minutes after last bronchodilator dose 5, 1, 2