What are the guidelines for managing asthma exacerbations?

Management of Asthma Exacerbations

The cornerstone of asthma exacerbation management is prompt administration of systemic corticosteroids, high-dose inhaled beta-agonists, and supplemental oxygen for patients with oxygen saturation <90%. 1

Initial Assessment and Classification

Severity Assessment

• Mild exacerbation: Dyspnea only with activity, PEF ≥70% of predicted or personal best 2
• Moderate exacerbation: Dyspnea interferes with usual activity, PEF 40-69% of predicted or personal best 2
• Severe exacerbation: Features include:
  • Too breathless to complete sentences in one breath
  • Respiratory rate >25 breaths/min
  • Heart rate >110 beats/min
  • PEF <50% of predicted or personal best
  • Use of accessory muscles 1
• Life-threatening features:
  • PEF <33% of predicted or personal best
  • Silent chest, cyanosis
  • Feeble respiratory effort, exhaustion
  • Confusion, coma
  • Bradycardia or hypotension 1

High-Risk Patients

Identify patients at high risk for asthma-related death:

• Previous severe exacerbation requiring intubation or ICU admission
• ≥2 hospitalizations or >3 ED visits in the past year
• Use of >2 canisters of SABA per month
• Difficulty perceiving airway obstruction
• Low socioeconomic status or inner-city residence
• Psychosocial problems or psychiatric disease
• Comorbidities 2

Treatment Protocol

Immediate Interventions

1. Oxygen therapy:

   • Administer supplemental oxygen if saturation <90%
   • Target oxygen saturation 94-98%
   • Monitor oxygen saturation continuously 1

2. Bronchodilators:

   • High-dose inhaled beta-agonists (salbutamol 5 mg or terbutaline 10 mg via oxygen-driven nebulizer, or multiple actuations of albuterol MDI with spacer)
   • For severe exacerbations: Add ipratropium bromide 0.5 mg to nebulized beta-agonist 1
   • Administer repetitively or continuously to rapidly reverse airflow obstruction 2

3. Systemic corticosteroids:

   • Administer immediately for moderate to severe exacerbations
   • Adults: Prednisolone 30-60 mg orally in a single dose
   • Children: Prednisolone 1-2 mg/kg (maximum 60 mg) 1
   • Clinical benefits expected within 6-12 hours 1
   • Oral and IV routes have similar efficacy 3

Monitoring Response

• Measure PEF 15-30 minutes after starting treatment and after each subsequent dose
• Reassess after initial 3 doses of bronchodilator (60-90 minutes after treatment initiation)
• Monitor for signs of deterioration or improvement 1

Additional Treatments

• Magnesium sulfate: Consider IV magnesium sulfate for severe exacerbations not responding to initial treatment 2
• Helium: May be considered in severe exacerbations, though not for routine use 2

Treatments NOT Recommended

• Antibiotics: Reserve only for cases with clear evidence of bacterial infection 1
• Leukotriene receptor antagonists: Not recommended for acute exacerbations 2
• Sedatives: Avoid sedatives of any kind during asthma exacerbations 1
• Inhaled corticosteroids alone: Not effective as sole therapy for acute exacerbations 4

Hospitalization Criteria

Consider hospital admission if:

• No response or worsening after initial treatment
• PEF remains <40% of predicted after treatment
• Oxygen saturation <90% despite supplemental oxygen
• Signs of impending respiratory failure
• High-risk features present 1
• Poor respiratory effort, hypotension, bradycardia, agitation, accessory muscle use, tachypnea 2

Discharge Criteria and Follow-up

Patients can generally be discharged when:

• FEV1 or PEF ≥70% of predicted value or personal best
• Symptoms are minimal or absent 2
• Patient has been stable on discharge medications for 24 hours 1

Discharge Plan

1. Medications:

   • Prescribe systemic corticosteroids for 3-10 days after discharge 2
   • Continue inhaled corticosteroid therapy if already prescribed
   • Consider initiating inhaled corticosteroids if not already on them 2

2. Follow-up:

   • Arrange follow-up with primary care provider within 1 week
   • Schedule follow-up appointment in respiratory clinic within 4 weeks 1

3. Education:

   • Provide written asthma action plan
   • Ensure proper inhaler technique
   • Instruct on monitoring symptoms and PEF
   • Educate on when to seek medical attention 2

Home Management of Exacerbations

Instruct patients to:

• Use a written asthma action plan
• Recognize early indicators of exacerbation
• Adjust medications by increasing SABA and, when indicated, adding oral corticosteroids
• Remove or withdraw from environmental triggers
• Monitor response to treatment
• Seek medical attention if symptoms worsen or don't improve 2

Special Considerations

• Duration of corticosteroids: A 1-week course of oral prednisolone may be as effective as a 2-week course for most exacerbations 5
• Oral vs. IV steroids: Oral prednisolone is as effective as IV hydrocortisone for hospitalized patients 3
• Difficult-to-control asthma: Approximately 5% of patients have difficult-to-control asthma requiring specialist assessment 6

Remember that early and aggressive treatment of asthma exacerbations is essential to prevent progression to life-threatening respiratory failure and to reduce morbidity and mortality.