What is the recommended acute management for a patient presenting with an asthma exacerbation?

Acute Asthma Exacerbation Management

Immediately administer high-flow oxygen (40–60% via face mask targeting SaO₂ >90%), nebulized albuterol 5 mg (or 4–8 puffs via MDI with spacer) every 20 minutes for three doses, and systemic corticosteroids (prednisolone 30–60 mg orally or IV hydrocortisone 200 mg) within the first 15–30 minutes—all three therapies must be given simultaneously, not sequentially. 1, 2

Initial Assessment and Severity Recognition (First 15–30 Minutes)

Obtain objective measurements immediately—failure to measure peak expiratory flow (PEF) or FEV₁ is the most common preventable cause of asthma deaths. 1 Never rely on subjective clinical impression alone, as physicians frequently underestimate severity. 1

Severe Exacerbation Features:

• Inability to complete sentences in one breath 1, 2
• Respiratory rate >25 breaths/min 1, 2
• Heart rate >110 beats/min 1, 2
• PEF <50% of predicted or personal best 1, 2

Life-Threatening Features Requiring Immediate ICU Consideration:

• PEF <33% predicted 1
• Silent chest, cyanosis, or feeble respiratory effort 3, 1
• Bradycardia or hypotension 3, 1
• Exhaustion, confusion, or altered mental status 3, 1
• Normal or elevated PaCO₂ ≥42 mmHg in a breathless patient 1
• Severe hypoxia (PaO₂ <8 kPa/60 mmHg) despite oxygen 3

Immediate Treatment Protocol (First Hour)

Oxygen Therapy

Deliver 40–60% oxygen via face mask or nasal cannula, targeting SaO₂ >90% (>95% in pregnancy or cardiac disease). 1, 2 CO₂ retention is not aggravated by oxygen therapy in asthma. 3

Bronchodilator Therapy

• Adults: Albuterol 5 mg (or terbutaline 10 mg) via oxygen-driven nebulizer every 20 minutes for three doses 1, 4
• Alternative: 4–8 puffs via MDI with spacer every 20 minutes for three doses (equally effective when properly administered) 1, 2
• Children <15 kg: Use half doses (2.5 mg albuterol) 1, 4

Systemic Corticosteroids (Must Be Given Immediately)

Do not delay corticosteroids while "trying bronchodilators first"—clinical benefits require 6–12 hours minimum to manifest. 1, 5

• Adults: Prednisolone 30–60 mg orally OR IV hydrocortisone 200 mg 3, 1, 2
• Children: Prednisolone 1–2 mg/kg (maximum 40 mg) 3, 1
• Oral route is as effective as IV and preferred when tolerated 1, 2

Ipratropium Bromide for Moderate-to-Severe Exacerbations

Add ipratropium 0.5 mg to nebulizer (or 8 puffs via MDI) every 20 minutes for three doses—this combination reduces hospitalizations, particularly in severe airflow obstruction. 1, 2, 6

Reassessment After Initial Treatment (15–30 Minutes)

Re-measure PEF/FEV₁ and reassess symptoms and vital signs. 1, 2 Response to treatment is a better predictor of hospitalization need than initial severity. 1

Good Response (PEF >75% predicted):

• Continue monitoring with PEF chart 1
• Step up maintenance inhaled corticosteroids 1
• Arrange follow-up within 48 hours 1

Incomplete Response (PEF 50–75% predicted):

• Continue nebulized β-agonist every 4–6 hours 3, 1
• Continue oral corticosteroids 1
• Consider hospital admission if severe features persist 1

Poor Response (PEF <50% predicted or severe features persist):

• Maintain oxygen 1
• Increase nebulized β-agonist frequency to every 15–30 minutes 3, 1
• Repeat ipratropium 0.5 mg every 20 minutes 1
• Arrange immediate hospital admission 1

Adjunctive Therapies for Refractory Cases

Intravenous Magnesium Sulfate

Consider for severe exacerbations with PEF <40% after initial treatment or life-threatening features. 1, 2, 6

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

Intravenous Aminophylline or Beta-Agonists

For life-threatening features unresponsive to initial measures: 3, 1

• Aminophylline 250 mg over 20 minutes OR salbutamol/terbutaline 250 µg over 10 minutes 3
• Critical pitfall: Do NOT give bolus aminophylline to patients already taking oral theophyllines 3, 1

Critical Pitfalls to Avoid

• Never administer sedatives of any kind—this is absolutely contraindicated 3, 1
• Never delay corticosteroid administration while trying bronchodilators first 1
• Never rely solely on subjective assessment—objective PEF/FEV₁ measurement is essential 1
• Avoid methylxanthines (theophylline) due to increased side effects without superior efficacy 1
• Avoid aggressive hydration in older children and adults 1
• Avoid antibiotics unless strong evidence of bacterial infection (pneumonia, sinusitis) 1

Hospital Admission Criteria

Immediate admission required for: 1

• Any life-threatening feature present
• Severe attack persisting after initial treatment
• PEF <33% predicted after treatment
• PEF <50% predicted after 1–2 hours of intensive therapy

Lower threshold for admission when: 3, 1

• Presentation in afternoon/evening
• Recent nocturnal or worsening symptoms
• Previous severe attacks requiring intubation or ICU
• ≥2 hospitalizations or ≥3 ED visits in past year
• Poor social circumstances limiting reliable monitoring

ICU Transfer Criteria

Transfer with a physician prepared to intubate when: 3, 1

• Deteriorating PEF despite treatment
• Exhaustion, feeble respirations, or altered mental status
• PaCO₂ ≥42 mmHg or rising
• Worsening hypoxia despite oxygen
• Silent chest or cyanosis
• Coma or respiratory arrest

Discharge Planning (After Stabilization)

Discharge criteria: 1, 2

• PEF >75% of predicted or personal best
• Diurnal variability <25%
• Symptoms minimal or absent
• SaO₂ stable on room air
• Stable for 30–60 minutes after last bronchodilator dose

At discharge, ensure: 3, 1

• Continue oral corticosteroids for 5–10 days (no taper needed for courses <10 days) 1, 2
• Initiate or continue inhaled corticosteroids 1, 2
• Verify and record correct inhaler technique 3, 1
• Provide written asthma action plan 3, 1
• Provide peak flow meter 3, 1
• Arrange primary care follow-up within 1 week 3, 1
• Arrange specialist follow-up within 4 weeks 3, 1