What is the immediate treatment for acute asthma exacerbation?

Immediate Treatment for Acute Asthma Exacerbation

Administer oxygen to maintain saturation >90% (>95% in pregnancy or heart disease), give albuterol 2.5-5 mg via nebulizer or 4-8 puffs via MDI with spacer every 20 minutes for 3 doses, and immediately start systemic corticosteroids with prednisone 40-60 mg orally or hydrocortisone 200 mg IV. 1

Initial Assessment and Oxygen Therapy

• Immediately administer supplemental oxygen through nasal cannula or mask to maintain oxygen saturation >90% (>95% in pregnant patients or those with heart disease). 1, 2
• Monitor oxygen saturation continuously until a clear response to bronchodilator therapy occurs. 1, 2
• Assess severity based on clinical features: severe exacerbation includes inability to complete sentences, respiratory rate >25/min, heart rate >110/min, and PEF <50% predicted. 1
• Life-threatening features include PEF <33% predicted, silent chest, cyanosis, altered mental status, PaCO₂ ≥42 mmHg, or inability to speak. 1

First-Line Bronchodilator Therapy

• Albuterol is the first-line treatment for all asthma exacerbations with two equally effective delivery options: 1, 2
  • Nebulizer: 2.5-5 mg every 20 minutes for 3 doses, then 2.5-10 mg every 1-4 hours as needed 1, 3
  • MDI with spacer: 4-8 puffs every 20 minutes for up to 3 doses, then as needed 1, 2
• For severe exacerbations (PEF <40%), consider continuous nebulization of albuterol rather than intermittent dosing. 2
• Reassess the patient 15-30 minutes after the initial bronchodilator dose, measuring PEF or FEV₁ and vital signs. 1, 2

Systemic Corticosteroids - Critical Early Intervention

• Administer systemic corticosteroids immediately and early in all moderate to severe exacerbations, as clinical benefits may not occur for 6-12 hours. 1, 4, 5
• Oral administration is as effective as intravenous and is preferred unless the patient cannot tolerate oral intake. 1
• Adult dosing: Prednisone 40-60 mg orally in single or divided doses 1, 2
• Pediatric dosing: 1-2 mg/kg/day (maximum 60 mg/day) 1, 6
• Alternative IV option: Hydrocortisone 200 mg IV initially, then every 6 hours 1
• Duration: 5-10 days for outpatient therapy; no tapering necessary for courses <10 days. 1

Adjunctive Ipratropium Bromide

• Add ipratropium bromide to albuterol for all moderate to severe exacerbations, as this combination reduces hospitalizations, particularly in patients with severe airflow obstruction. 1, 5
• Dosing: 0.5 mg via nebulizer or 8 puffs via MDI every 20 minutes for 3 doses, then as needed. 1, 2
• The benefits of ipratropium are most pronounced in the emergency department but are not sustained after hospital admission. 5

Severe or Refractory Exacerbations

• For severe exacerbations not responding to initial therapy, consider intravenous magnesium sulfate 2 g IV over 20 minutes (most effective when administered early). 1, 2
• Pediatric magnesium dosing: 25-75 mg/kg up to 2 g maximum. 1
• If no improvement after 15-30 minutes, increase nebulized beta-agonist frequency to every 15 minutes. 1
• Consider continuous albuterol nebulization for life-threatening exacerbations. 1

Monitoring and Reassessment Strategy

• Response to treatment is a better predictor of hospitalization need than initial severity. 1, 2
• Measure PEF or FEV₁ before and after each treatment to assess response. 1, 2
• Reassess after 3 doses of bronchodilator (60-90 minutes), evaluating subjective response, physical findings, and objective measurements. 1
• Monitor for signs of impending respiratory failure: inability to speak, altered mental status, intercostal retractions, worsening fatigue, and PaCO₂ ≥42 mmHg. 1, 2

Critical Pitfalls to Avoid

• Never administer sedatives of any kind to patients with acute asthma exacerbation. 1, 2
• Do not delay intubation once it is deemed necessary; it should be performed semi-electively before respiratory arrest occurs. 1
• Avoid methylxanthines (theophylline) due to increased side effects without superior efficacy. 1, 7
• Do not routinely prescribe antibiotics unless there is strong evidence of bacterial infection (pneumonia or sinusitis). 1, 8
• Avoid aggressive hydration in older children and adults, chest physiotherapy, and mucolytics. 1

Disposition Criteria

• Discharge criteria: PEF >70-75% of predicted or personal best, stable on discharge medications for 24 hours, proper inhaler technique demonstrated, and diurnal variability <25%. 1, 6
• Ensure patients have a written self-management plan and arrange follow-up with primary care within 1 week. 1
• Consider hospital admission for life-threatening features or severe attack persisting after initial treatment. 1