What is the management of acute asthma in children?

Management of Acute Asthma in Children

Immediately administer high-flow oxygen via face mask, nebulized salbutamol (5 mg for children >20 kg or 2.5 mg for children <20 kg), intravenous hydrocortisone, and add ipratropium 100 mg nebulized every 6 hours for all children presenting with acute severe asthma. 1, 2, 3

Recognition of Acute Severe Asthma

Identify children with acute severe asthma by the presence of any of these features:

• Too breathless to talk or feed 1, 3
• Respiratory rate >50 breaths/min 1
• Pulse >140 beats/min 1
• Peak expiratory flow (PEF) <50% predicted (if measurable in older children) 1

Life-Threatening Features Requiring Immediate Escalation

Recognize life-threatening asthma by:

• PEF <33% predicted or poor respiratory effort 1
• Cyanosis, silent chest, or fatigue/exhaustion 1
• Agitation or reduced level of consciousness 1

Critical pitfall: Children with severe attacks may not appear distressed, and assessment in very young children may be difficult—the presence of ANY of these features should trigger immediate aggressive treatment. 1

Immediate Treatment Protocol

First-Line Therapy (All Patients)

• High-flow oxygen via face mask to maintain SaO₂ >92% 1, 2, 3
• Nebulized salbutamol: 5 mg for children >20 kg or 2.5 mg for children <20 kg (half doses in very young children), delivered via oxygen-driven nebulizer 1, 2, 3
• Intravenous hydrocortisone immediately 1, 3
• Ipratropium 100 mg nebulized every 6 hours 1, 2, 3

Additional Therapy for Life-Threatening Features

If life-threatening features are present, add intravenous aminophylline: 5 mg/kg over 20 minutes followed by maintenance infusion of 1 mg/kg/hour. 1 Omit the loading dose if the child is already receiving oral theophyllines. 1

Important note: CO₂ retention is not aggravated by oxygen therapy in asthma—never withhold oxygen. 1

Subsequent Management Based on Response

If Patient is Improving After 15-30 Minutes

Continue:

• High-flow oxygen 1, 3
• Oral prednisolone 1-2 mg/kg daily (maximum 40 mg) 1, 3
• Nebulized β-agonist every 4 hours 1, 3

If Patient is NOT Improving After 15-30 Minutes

Escalate treatment:

• Continue oxygen and steroids 1
• Increase nebulized β-agonist frequency to every 15-30 minutes 1, 3
• Continue ipratropium 100 mg nebulized every 6 hours until improvement starts 1, 3

Evidence note: The benefit of ipratropium is primarily in the emergency department setting; benefits are not sustained after hospital admission, but continue until clinical improvement is evident. 4

Monitoring Requirements

Essential Monitoring Parameters

• Repeat PEF measurement 15-30 minutes after starting treatment (if age-appropriate) 1, 2, 3
• Continuous pulse oximetry to maintain SaO₂ >92% 1, 2, 3
• Chart PEF before and after β-agonist administration and at least 4 times daily throughout hospital stay 1, 2, 3

Important caveat: Blood gas estimations are rarely helpful in deciding initial management in children. 1 However, if initial oxygen saturation is concerning, pulse oximetry values >90% are generally reassuring, though CO₂ retention may still be missed. 4, 5

ICU Transfer Criteria

Transfer to intensive care unit accompanied by a physician prepared to intubate if:

• Deteriorating PEF, worsening or persisting hypoxia 1
• Confusion or drowsiness 1
• Exhaustion, coma, or respiratory arrest 1

Discharge Criteria and Planning

Patients should only be discharged when:

• On discharge medication for 24 hours with documented proper inhaler technique 1, 3
• PEF >75% of predicted or best (if recorded) 1, 3
• PEF diurnal variability <25% 1, 3

Discharge Medications and Follow-up

Ensure patients leave with:

• Oral steroid tablets and inhaled steroids in addition to bronchodilators 1
• Peak flow meter (if age-appropriate) and written self-management plan 1, 6
• GP follow-up arranged within 1 week 1
• Respiratory clinic follow-up within 4 weeks 1

Common Pitfalls to Avoid

• Never use sedatives in acute asthma—they can mask deterioration and precipitate respiratory arrest 1
• Do not delay corticosteroids—clinical benefits may not occur for 6-12 hours, so early administration is critical 4, 5
• Avoid overreliance on short-acting β-agonists without adequate controller medications in the long-term management 6
• Do not underestimate severity based on appearance alone—children may not appear distressed despite severe obstruction 1
• Never withhold oxygen due to concerns about CO₂ retention in asthma 1

Special Considerations for Very Young Children

For children younger than 2 years with acute wheezing and history of recurrent episodes:

• A trial of nebulized β-agonists is warranted (0.15 mg/kg per dose) 7
• Use half doses of standard pediatric dosing for very young children 1, 2
• Clinical assessment may be particularly difficult—rely on objective measures when possible (respiratory rate, oxygen saturation, accessory muscle use) 1, 7