When is hospitalization recommended for asthma exacerbations?

Hospital Admission for Asthma Exacerbations

Patients with severe exacerbations (PEF <40% predicted after initial treatment) or life-threatening features (PEF <33% predicted, silent chest, cyanosis, altered mental status, or PaCO₂ ≥42 mmHg) require immediate hospital admission. 1

Severity-Based Admission Algorithm

Immediate Admission Required (Life-Threatening Features)

• Admit immediately if any of the following are present: PEF <33% predicted or personal best, silent chest, cyanosis, feeble respiratory effort, bradycardia, hypotension, exhaustion, confusion, drowsiness, or coma 1, 2
• Altered mental status, inability to speak, or PaCO₂ ≥42 mmHg in a breathless patient mandate immediate hospital referral 1, 2
• Severe hypoxia (PaO₂ <8 kPa) or low pH on arterial blood gas requires admission 2

Admission Based on Response to Initial Treatment

• After 1-2 hours of intensive treatment, reassess using objective measures 1, 2
• Admit if PEF remains <40% predicted after initial bronchodilator therapy (three doses over 60-90 minutes) 1
• Patients with PEF 40-69% predicted (moderate exacerbation) after initial treatment may require admission, particularly with a 6% relapse rate within 10 days even with glucocorticoids 1
• Discharge is appropriate when PEF reaches >70% predicted after initial treatment, with minimal symptoms and stable oxygen saturation 1, 2

Clinical Features Indicating Admission Need

• Inability to complete sentences in one breath, respiratory rate >25 breaths/min, heart rate >110 beats/min, or use of accessory muscles persisting after initial treatment 1, 2
• Poor respiratory effort, hypotension, agitation, tachypnea, or accessory muscle use despite therapy 3
• Moderately severe asthma not responding to β2-agonist therapy after approximately 2 hours 3

Risk Factors Lowering Admission Threshold

Timing and Presentation Factors

• Lower threshold for admission if presenting in afternoon/evening rather than morning 1, 2
• Recent deterioration, nocturnal asthma exacerbations, or onset of nighttime symptoms 3, 1

Historical Risk Factors

• Previous severe life-threatening asthma episodes or history of near-fatal asthma 3, 1
• Previous intubation or intensive care unit admissions 1
• Multiple recent emergency department visits or hospitalizations 1

Social and Behavioral Factors

• Home circumstances that do not allow safe or reliable treatment 3
• Poor symptom perception or assessment of severity 1
• Concerning social circumstances or lack of reliable follow-up 1

Pediatric-Specific Admission Criteria

• Infants and young children have higher risk of respiratory failure and require lower threshold for admission 1
• Admit pediatric patients with respiratory rate >60 breaths/min, SaO₂ <90-92%, or lack of response to short-acting β₂-agonists 1
• Age itself was recommended as an indication for hospital admission in some guidelines 3

Complications Requiring Admission

• Presence of complications such as pneumothorax, consolidation, or pulmonary edema 3
• Respiratory failure or severe exacerbations with past history of severe episodes 3

Safe Discharge Criteria (When Admission Not Required)

• PEF >75% predicted or personal best with sustained response to bronchodilators 1, 2
• Diurnal variability <25% and no nocturnal symptoms 1
• Adequate home circumstances and reliable follow-up arranged 1
• Patient stable for 30-60 minutes after last bronchodilator dose 2
• All discharged patients require oral corticosteroids for 5-10 days, increased inhaled steroids, written action plan, PEF meter with education, and follow-up within 1 week 1

Common Pitfalls to Avoid

• Underestimating severity is the most critical error—patients, families, and clinicians frequently fail to recognize dangerous exacerbations due to inadequate objective measurements 2
• Relying solely on initial presentation rather than response to treatment—response to therapy is a better predictor of hospitalization need than initial severity 2, 4
• Failing to obtain objective measurements (PEF or FEV₁) before making disposition decisions 2
• Discharging patients too early without ensuring 30-60 minutes of stability after last bronchodilator 2