What is the best treatment approach for a patient experiencing an acute asthma attack?

Acute Asthma Attack Treatment

Immediately administer high-flow oxygen (40-60%) to maintain oxygen saturation >92%, nebulized albuterol 2.5-5 mg (or 4-8 puffs via MDI with spacer) every 20 minutes for 3 doses, and systemic corticosteroids (prednisolone 40-60 mg orally or hydrocortisone 200 mg IV) within the first 15-30 minutes—do not delay steroids while "trying bronchodilators first." 1, 2

Initial Assessment and Severity Recognition

Assess severity objectively within the first 15-30 minutes using peak expiratory flow (PEF) or FEV₁, as underestimation is the most common preventable cause of asthma deaths 1. Severe exacerbation features include:

• Inability to complete sentences in one breath 3, 1, 2
• Respiratory rate >25 breaths/min 3, 1, 2
• Heart rate >110 beats/min 3, 1, 2
• PEF <50% of predicted or personal best 3, 1, 2

Life-threatening features requiring immediate ICU consideration include:

• PEF <33% predicted 1, 2
• Silent chest on auscultation 1, 2
• Cyanosis or feeble respiratory effort 1, 2
• Altered mental status, confusion, or drowsiness 3, 1, 2
• PaCO₂ ≥42 mmHg (normal or elevated CO₂ in a breathless patient is ominous) 1, 2
• Bradycardia or hypotension 1, 2

Immediate First-Line Treatment Protocol

Within the first 15-30 minutes, execute this three-pronged approach simultaneously:

1. Oxygen Therapy

Administer high-flow oxygen (40-60%) via face mask to maintain SaO₂ >92% (>95% in pregnant patients or those with cardiac disease) 1, 2. Continue oxygen monitoring until clear response to bronchodilator therapy occurs 1.

2. Bronchodilator Therapy

Nebulized albuterol is the cornerstone of acute treatment 2:

• Adults and children ≥15 kg: Albuterol 2.5-5 mg via oxygen-driven nebulizer OR 4-8 puffs via MDI with spacer every 20 minutes for 3 doses 1, 2, 4
• Children <15 kg: Half doses (albuterol 2.5 mg) 1
• The nebulizer and MDI with spacer are equally effective when properly administered 1

3. Systemic Corticosteroids - Critical Early Intervention

Administer immediately—clinical benefits require 6-12 hours minimum, so never delay while trying bronchodilators first 1, 5:

• Adults: Prednisolone 30-60 mg orally (preferred) OR hydrocortisone 200 mg IV if unable to take oral 1, 2, 6
• Children: Prednisolone 1-2 mg/kg (maximum 40 mg) orally 3, 1, 2
• Oral administration is as effective as intravenous and less invasive 1

Reassessment at 15-30 Minutes

Measure PEF and reassess clinical status after initial treatment 1, 2. Response to treatment is a better predictor of hospitalization need than initial severity 1.

If Patient is Improving:

• Continue high-flow oxygen 3
• Continue prednisolone 30-60 mg daily (or IV hydrocortisone 200 mg every 6 hours) 3, 1
• Continue nebulized albuterol every 4-6 hours 3, 1

If Patient is NOT Improving After 15-30 Minutes:

Escalate treatment immediately:

• Continue oxygen and steroids 3
• Increase nebulized albuterol frequency to every 15-30 minutes, or consider continuous nebulization for severe cases 3, 1
• Add ipratropium bromide 0.5 mg to nebulizer every 20 minutes for 3 doses, then every 4-6 hours—this combination reduces hospitalizations, particularly in severe airflow obstruction 3, 1, 7

Adjunctive Therapies for Severe/Refractory Cases

Intravenous Magnesium Sulfate

Consider for life-threatening exacerbations or severe exacerbations remaining after 1 hour of intensive treatment 1, 2:

• Dose: 2 g IV over 20 minutes for adults; 25-75 mg/kg (maximum 2 g) for children 1
• Significantly increases lung function and decreases hospitalization necessity 1
• Causes relaxation of bronchial smooth muscle with minor side effects 1

Intravenous Beta-Agonists

For severe refractory asthma with PEF <40% after initial treatment, consider IV salbutamol or terbutaline 250 µg over 10 minutes 1. However, this produces more side effects than carefully administered therapy and should be reserved for truly refractory cases 8.

Critical Pitfalls to Avoid

Never administer sedatives of any kind to patients with acute asthma—this is absolutely contraindicated and can precipitate respiratory failure 3, 1, 2, 6.

Other critical errors to avoid:

• Underestimating severity based on subjective assessment—always measure PEF or FEV₁ objectively 1, 5
• Delaying corticosteroid administration while "trying bronchodilators first"—steroids must be given immediately 1
• Administering bolus aminophylline to patients already taking oral theophyllines 3, 1
• Using methylxanthines (theophylline) routinely—they have increased side effects without superior efficacy 1, 7
• Aggressive hydration in older children and adults (may be appropriate for infants and young children only) 1
• Routine prescription of antibiotics unless strong evidence of bacterial infection (pneumonia, sinusitis) exists 1

Monitoring During Treatment

Continuous monitoring parameters include:

• Pulse oximetry to maintain SaO₂ >92% 1, 2
• PEF measurement before and after each nebulization 1, 2
• Respiratory rate and heart rate every 15-30 minutes initially 2
• Arterial blood gas if PEF <25% predicted, severe distress, or suspected hypoventilation 2

Hospital Admission Criteria

Admit to hospital immediately if:

• Any life-threatening features present 3, 1, 6
• Features of severe attack persisting after initial treatment 3, 1, 6
• PEF <33% after treatment 3, 1
• PEF <50% predicted after 1-2 hours of intensive treatment 1

Lower threshold for admission if:

• Presentation in afternoon or evening 3, 1
• Recent nocturnal symptoms or previous severe attacks 3, 1, 6
• Previous intubation or ICU admission for asthma 1
• ≥2 hospitalizations or ≥3 ED visits in past year 1
• Poor social circumstances or inability to assess own condition 3, 1

ICU Transfer Criteria

Transfer to ICU accompanied by a physician prepared to intubate if:

• Deteriorating PEF or worsening exhaustion 3
• Feeble respirations or persistent/worsening hypoxia 3
• Rising PaCO₂ ≥42 mmHg 1, 2
• Confusion, drowsiness, coma, or respiratory arrest 3, 1
• Silent chest, cyanosis, or bradycardia 1, 2

Do not delay intubation once deemed necessary—it should be performed semi-electively before respiratory arrest occurs 1. Consider other treatments (IV magnesium, heliox) before resorting to intubation, but when intubation becomes necessary, ensure the most expert available physician performs it 1, 2.

Discharge Criteria

Patients may be discharged when:

• PEF ≥70% of predicted or personal best 1, 6
• Symptoms minimal or absent 1
• Oxygen saturation stable on room air 1
• Patient stable for 30-60 minutes after last bronchodilator dose 1
• Been on discharge medication for 24 hours 3
• Inhaler technique checked and recorded 3, 6

At discharge, ensure:

• Continuation of oral corticosteroids for 5-10 days (no taper needed for courses <10 days) 1, 6
• Initiation or continuation of inhaled corticosteroids 1, 6
• Provision of written asthma action plan 1, 6
• Own PEF meter and self-management plan 3, 6
• GP follow-up arranged within 1 week 3, 6
• Specialist follow-up within 4 weeks 3