What is the management for bronchial asthma in acute exacerbation at the Emergency Room (ER) level?

Management of Acute Asthma Exacerbation in the Emergency Department

Immediately administer oxygen to maintain SpO2 >90% (>95% in pregnant patients or those with heart disease), nebulized albuterol 2.5-5 mg every 20 minutes for 3 doses, and systemic corticosteroids (prednisone 40-60 mg orally or hydrocortisone 200 mg IV) within the first 15-30 minutes of presentation. 1, 2, 3

Initial Assessment and Severity Classification

Assess severity immediately using objective measures combined with clinical presentation 2:

Mild Exacerbation:

• Dyspnea only with activity
• PEF ≥70% predicted/personal best
• Speaks in sentences 1

Moderate Exacerbation:

• Dyspnea interfering with usual activity
• PEF 40-69% predicted
• Speaks in phrases 1

Severe Exacerbation:

• Dyspnea at rest
• PEF <40% predicted
• Respiratory rate >25 breaths/min
• Heart rate >110 beats/min
• Inability to complete sentences in one breath 1, 2, 3

Life-Threatening Features (requiring immediate ICU consideration):

• PEF <33% predicted
• Silent chest
• Cyanosis
• Altered mental status or confusion
• Feeble respiratory effort
• Bradycardia or hypotension
• PaCO2 ≥42 mmHg (normal or elevated CO2 in a breathless asthmatic is ominous) 2, 3

Primary Treatment Protocol

Oxygen Therapy

• Administer via nasal cannula or mask to maintain SpO2 >90% (>95% in pregnant patients or cardiac disease) 1, 2, 3
• Monitor oxygen saturation continuously until clear response to bronchodilator therapy 1, 2

Bronchodilator Therapy (First-Line)

Albuterol dosing options 1, 2, 3:

• Nebulizer: 2.5-5 mg every 20 minutes for 3 doses, then 2.5-10 mg every 1-4 hours as needed 1, 4
• MDI with spacer: 4-8 puffs every 20 minutes for 3 doses, then as needed 1, 2
• For severe exacerbations (PEF <40%): Consider continuous nebulization rather than intermittent dosing 1, 2

Both delivery methods (nebulizer and MDI with spacer) are equally effective when properly administered 2

Systemic Corticosteroids (Critical Early Intervention)

Administer within the first 15-30 minutes—do not delay to "try bronchodilators first" 2, 3:

• Adults: Prednisone 40-60 mg orally in single or divided doses 1, 2, 3
• Children: 1-2 mg/kg/day (maximum 60 mg/day) 1, 2
• If unable to take oral: Hydrocortisone 200 mg IV 2, 3

Oral administration is as effective as IV and less invasive 2, 3. Early administration may reduce hospitalization rates 1, 3.

Adjunctive Therapies for Moderate-to-Severe Exacerbations

Ipratropium Bromide

Add to albuterol for all moderate-to-severe exacerbations 1, 2, 3:

• Nebulizer: 0.5 mg every 20 minutes for 3 doses, then as needed 1, 2
• MDI: 8 puffs every 20 minutes for 3 doses, then as needed 1, 2

This combination reduces hospitalizations, particularly in patients with severe airflow obstruction 2, 3

Intravenous Magnesium Sulfate

Consider for severe refractory asthma (PEF <40% after initial treatment) or life-threatening features 1, 2, 3:

• Adults: 2 g IV over 20 minutes 1, 2, 3, 5, 6
• Children: 25-75 mg/kg (maximum 2 g) IV over 20 minutes 2

Most effective when administered early in the treatment course 1. Significantly increases lung function and decreases hospitalization necessity 2, 5, 6

Reassessment Protocol

Reassess 15-30 minutes after starting treatment 1, 2, 3:

• Measure PEF or FEV1 before and after treatments 1, 2
• Assess symptoms and vital signs 1, 2
• Response to treatment is a better predictor of hospitalization need than initial severity 1, 3

After 60-90 minutes (3 doses of bronchodilator):

Good Response (PEF ≥70% predicted):

• Minimal symptoms
• Stable on room air
• Observe 30-60 minutes after last bronchodilator dose 2
• Consider discharge with oral corticosteroids for 5-10 days (no taper needed for courses <10 days) 2, 3

Incomplete Response (PEF 40-69% predicted):

• Continue intensive treatment
• Admit to hospital ward 2

Poor Response (PEF <40% predicted):

• Admit to hospital
• Consider ICU admission if life-threatening features present 2

Critical Pitfalls to Avoid

• Never delay corticosteroid administration to "try bronchodilators first"—steroids must be given immediately 2, 3
• Never administer sedatives of any kind in acute asthma 1, 2, 3
• Avoid methylxanthines (theophylline/aminophylline) due to increased side effects without superior efficacy 2, 5, 6
• Do not delay intubation once deemed necessary—perform semi-electively before respiratory arrest 2
• Underestimating severity is common—always use objective measurements (PEF/FEV1), not just clinical impression 2, 3
• Monitor for impending respiratory failure: inability to speak, altered mental status, intercostal retraction, worsening fatigue, PaCO2 ≥42 mmHg 1, 2

Hospital Admission Criteria

Immediate admission indicated for 2, 3:

• Any life-threatening features present
• Features of severe attack persisting after initial treatment
• PEF <50% predicted after 1-2 hours of treatment 2
• Lower threshold for admission: afternoon/evening presentation, recent nocturnal symptoms, previous severe attacks, poor social circumstances 2, 3

Discharge Planning (When Appropriate)

Discharge criteria 2:

• PEF ≥70% predicted or personal best
• Symptoms minimal or absent
• Oxygen saturation stable on room air
• Stable for 30-60 minutes after last bronchodilator dose 2

At discharge, ensure 2, 3:

• Continue oral corticosteroids for 5-10 days (no taper needed) 2, 3
• Initiate or continue inhaled corticosteroids 2, 3
• Provide written asthma action plan 2
• Verify inhaler technique 2, 3
• Arrange follow-up within 1 week 2, 3