What is the initial treatment for a patient experiencing an acute asthma exacerbation according to the Global Initiative for Asthma (GINA) guidelines?

GINA Guideline for Acute Asthma Exacerbation

Immediate Initial Treatment (First Hour)

Begin high-dose inhaled short-acting beta-agonist (SABA) therapy immediately with albuterol 2.5-5 mg via nebulizer or 4-8 puffs via metered-dose inhaler (MDI) with spacer every 20 minutes for 3 doses, combined with systemic corticosteroids (prednisolone 40-60 mg orally or hydrocortisone 200 mg IV) and oxygen to maintain SaO₂ >90%. 1, 2

Oxygen Therapy

• Administer high-flow oxygen at 40-60% immediately via face mask or nasal cannula to maintain SaO₂ >90% (>95% in pregnant patients or those with cardiac disease). 2
• Continue oxygen monitoring until clear response to bronchodilator therapy occurs. 1

Bronchodilator Administration

• Albuterol dosing options are equally effective: nebulizer (2.5-5 mg) or MDI with spacer (4-8 puffs), both given every 20 minutes for 3 doses initially. 1, 2
• After initial 3 doses, continue albuterol 2.5-10 mg every 1-4 hours as needed based on clinical response. 1
• For severe exacerbations with PEF <40% predicted, consider continuous nebulization of albuterol rather than intermittent dosing. 3

Systemic Corticosteroids - Critical Early Intervention

• Administer systemic corticosteroids immediately, not after "trying bronchodilators first" - this is a critical pitfall to avoid. 1
• Adult dosing: prednisolone 40-60 mg orally (preferred route) or hydrocortisone 200 mg IV if unable to take oral medication. 1, 2
• Pediatric dosing: prednisolone 1-2 mg/kg/day (maximum 60 mg/day). 1
• Oral administration is as effective as intravenous and less invasive. 1

Severity Assessment Using Objective Measurements

Failure to make objective measurements is a common cause of preventable asthma deaths - always measure PEF or FEV₁ immediately. 2

Severe Exacerbation Features

• Inability to complete sentences in one breath 4, 2
• Respiratory rate >25 breaths/min 4, 2
• Heart rate >110 beats/min 4, 2
• PEF <50% of predicted or personal best 4, 2

Life-Threatening Features Requiring Immediate ICU Consideration

• PEF <33% of predicted or personal best 4, 1
• Silent chest, cyanosis, or feeble respiratory effort 4, 1
• Bradycardia or hypotension 4, 1
• Exhaustion, confusion, or coma 4, 1
• Normal or elevated PaCO₂ (≥42 mmHg) in a breathless patient 4, 1
• Severe hypoxia: PaO₂ <8 kPa irrespective of oxygen treatment 4

Adjunctive Therapy for Moderate-to-Severe Exacerbations

Ipratropium Bromide

• Add ipratropium bromide 0.5 mg via nebulizer or 8 puffs via MDI to albuterol for ALL moderate-to-severe exacerbations. 1, 2
• Dosing: 0.5 mg every 20 minutes for 3 doses, then as needed. 1, 2
• This combination reduces hospitalizations, particularly in patients with severe airflow obstruction. 1, 3

Intravenous Magnesium Sulfate

• Administer IV magnesium sulfate 2 g over 20 minutes for life-threatening features or severe exacerbations not responding after 1 hour of intensive treatment. 1, 2
• Pediatric dosing: 25-75 mg/kg (maximum 2 g) IV over 20 minutes. 1
• This significantly increases lung function and decreases hospitalization necessity. 1

Reassessment Protocol (15-30 Minutes After Initial Treatment)

Repeat PEF measurement 15-30 minutes after starting treatment and after 3 doses of bronchodilator (60-90 minutes total). 1, 2

Good Response (Discharge Eligible)

• PEF ≥70% of predicted or personal best 1
• Symptoms minimal or absent 1
• Patient stable for 30-60 minutes after last bronchodilator dose 1
• Oxygen saturation stable on room air 1

Incomplete Response (Hospital Ward Admission)

• PEF 40-69% predicted with persistent symptoms 1
• Continue intensive treatment with nebulized albuterol, ipratropium, and systemic corticosteroids. 1

Poor Response (ICU Consideration)

• PEF <40% predicted after initial treatment 1
• Warning signs of impending respiratory failure: drowsiness, confusion, inability to speak, worsening fatigue, silent chest, PaCO₂ ≥42 mmHg. 1
• Do not delay intubation once deemed necessary - perform semi-electively before respiratory arrest occurs. 1

Critical Pitfalls to Avoid

• Never administer sedatives of any kind to patients with acute asthma. 4, 1
• Do not give bolus aminophylline to patients already taking oral theophyllines. 4
• Avoid methylxanthines (theophylline) due to increased side effects without superior efficacy. 1
• Do not delay corticosteroid administration while "trying bronchodilators first." 1
• Avoid aggressive hydration in older children and adults. 1
• Do not routinely prescribe antibiotics unless strong evidence of bacterial infection (pneumonia or sinusitis) exists. 1

Hospital Admission Criteria

Immediate hospital referral is required for: 4, 1

• Any life-threatening features present 4
• Features of severe attack persisting after initial treatment 4
• PEF <33% of predicted after treatment 4

Lower threshold for admission applies to: 4

• Patients presenting in afternoon/evening rather than earlier in day 4
• Recent onset of nocturnal symptoms 4
• Previous severe attacks requiring ICU admission 4
• Poor social circumstances or concerning home environment 4

Discharge Planning and Follow-up

Discharge Criteria

• PEF >75% of predicted or personal best 1
• Symptoms minimal or absent 1
• Patient stable for 30-60 minutes after last bronchodilator dose 1
• Oxygen saturation stable on room air 1

Discharge Medications

• Continue oral corticosteroids for 5-10 days (no taper needed for courses <10 days). 1, 3
• Initiate or continue inhaled corticosteroids at discharge. 1, 3
• Patients at high risk of non-adherence may benefit from IM depot corticosteroid injection at discharge. 1

Patient Education and Follow-up

• Provide written asthma action plan before discharge. 1
• Review and verify inhaler technique. 1
• Arrange follow-up with primary care within 1 week. 4
• Arrange specialist clinic follow-up within 4 weeks. 1