Management of Acute Severe Asthma Exacerbations

Assessment and Treatment

• The American Thoracic Society recommends assessing the severity of asthma exacerbations based on symptoms such as breathlessness, respiratory rate, and peak expiratory flow (PEF), with severe features including too breathless to complete sentences, respiratory rate >25 breaths/min, PEF <50% of predicted normal, and heart rate >110 beats/min 3
• The British Thoracic Society suggests that life-threatening features of asthma exacerbations include PEF <33% of predicted normal, silent chest, cyanosis, feeble respiratory effort, bradycardia, hypotension, exhaustion, confusion, or coma 3
• The American College of Chest Physicians recommends levosalbutamol MDI at 8 puffs every 20 minutes for three doses, followed by 8 puffs hourly, as an appropriate treatment regimen for acute severe asthma exacerbations in adults, particularly when administered through a spacer device 1, 2
• High-dose β2-agonist administration, such as levosalbutamol MDI, is equivalent to nebulized therapy when administered with proper technique and coaching, and is recommended by the American Academy of Allergy, Asthma, and Immunology 2
• Systemic corticosteroids, such as prednisolone 30-60 mg orally or hydrocortisone 200 mg IV, should be administered immediately, and continued at high doses until PEF reaches 70% of predicted or personal best, as recommended by the National Asthma Education and Prevention Program 2, 3
• Oxygen therapy should be maintained to keep oxygen saturation >90% (>95% in pregnant women and patients with heart disease), and monitored until clear response to bronchodilator therapy, as suggested by the American Thoracic Society 4

Monitoring and Hospital Admission

• Peak expiratory flow (PEF) should be measured and recorded 15-30 minutes after starting treatment and thereafter according to response, and heart rate, respiratory rate, and oxygen saturation should be monitored, as recommended by the British Thoracic Society 3, 5
• Hospital admission should be considered if life-threatening features are present, features of severe asthma persist after initial treatment, PEF remains <33% of predicted or best value after treatment, or patient has had previous severe attacks, especially with rapid onset, as suggested by the American College of Emergency Physicians 5

Common Pitfalls to Avoid

• Underestimation of severity is a common pitfall, and objective measurements such as PEF and respiratory rate should be used to assess severity, as recommended by the National Asthma Education and Prevention Program 3
• Delayed corticosteroid administration can reduce the likelihood of hospitalization, and early administration is crucial, as suggested by the American Academy of Allergy, Asthma, and Immunology 4
• Inappropriate sedation is contraindicated in acute asthma, and multiple parameters (symptoms, vital signs, PEF) should be used to assess severity and response, as recommended by the American Thoracic Society 3, 5