What is the recommended levosalbutamol nebuliser dose, administration method, contraindications, monitoring, and escalation for a child with an acute asthma exacerbation?

Levosalbutamol Nebulization in Pediatric Acute Asthma Exacerbation

For children presenting with acute asthma exacerbation, administer salbutamol 5 mg (or 2.5 mg for children ≤2 years or <15 kg) via oxygen-driven nebulizer every 20 minutes for three doses in the first hour, combined with immediate systemic corticosteroids and supplemental oxygen to maintain SpO₂ >92%. 1, 2

Initial Assessment and Severity Recognition

Recognize severe exacerbation features immediately:

• Too breathless to talk or feed 1, 2
• Respiratory rate >50 breaths/minute 1, 2
• Heart rate >140 beats/minute 1, 2
• Use of accessory muscles of breathing 2
• Peak expiratory flow <50% predicted (if child can perform reliably, typically >5 years) 1, 2

Life-threatening features requiring immediate escalation:

• Peak flow <33% predicted or poor respiratory effort 1, 2
• Silent chest, cyanosis, or feeble respiratory effort 1, 2
• Altered consciousness, confusion, or exhaustion 1, 2
• SpO₂ <92% despite supplemental oxygen 2

Critical pitfall: Blood gas estimations are rarely helpful in deciding initial management in children and should not delay treatment. 1 However, a normal or elevated PaCO₂ in a breathless child is an ominous sign of impending respiratory failure. 1

Immediate Treatment Protocol (First Hour)

Oxygen Therapy

• Administer high-flow oxygen via face mask immediately to maintain SpO₂ >92% 1, 2
• Continue pulse oximetry monitoring throughout treatment 2

Bronchodilator Administration

Dosing:

• Standard dose: Salbutamol 5 mg via oxygen-driven nebulizer 1, 2
• Children ≤2 years or <15 kg: Reduce to 2.5 mg 1, 2
• Alternative: Terbutaline 10 mg (5 mg for young children) 1

Frequency: Every 20 minutes for three doses in the first hour 1, 2

Delivery method alternatives:

• Metered-dose inhaler with large volume spacer is equally effective: 4-8 puffs every 20 minutes for three doses 1, 2
• MDI with spacer may result in lower admission rates and fewer cardiovascular side effects in severe exacerbations 2
• Use face mask with spacer in very young children who cannot coordinate mouthpiece 1

Systemic Corticosteroids (Mandatory—Do Not Delay)

Critical principle: Administer corticosteroids immediately, not after "trying bronchodilators first"—this delay is a common preventable cause of treatment failure and mortality. 2

Dosing:

• Prednisolone 1-2 mg/kg orally (maximum 40-60 mg) 1, 2
• Continue daily for 3-5 days; no taper needed for courses <10 days 1, 2
• If vomiting or critically ill: IV hydrocortisone 100 mg six-hourly 1

Ipratropium Bromide (Add for Moderate-to-Severe Cases)

• Add ipratropium 100-250 mcg to nebulizer immediately for moderate-to-severe exacerbations 1, 2, 3, 4
• Repeat every 6 hours until improvement starts 1, 2
• Combination therapy significantly improves bronchodilation and reduces hospitalizations 3, 4

Reassessment at 15-30 Minutes

Measure and document:

• Peak expiratory flow (if child >5 years and able to perform) 1, 2
• Respiratory rate, heart rate, SpO₂ 1, 2
• Clinical asthma score 2

Response-based management:

Good Response (PEF >75% predicted, minimal symptoms)

• Continue usual maintenance therapy 1
• Monitor with PEF chart 1
• Arrange follow-up within 48 hours 1

Incomplete Response (PEF 50-75% predicted, persistent symptoms)

• Continue high-flow oxygen 1, 2
• Continue prednisolone 1-2 mg/kg daily 1, 2
• Continue nebulized β-agonist every 4 hours 1, 2
• Consider hospital admission 1

Poor Response (PEF <50% predicted or persistent severe features)

• Increase nebulized β-agonist frequency to every 15-30 minutes 1, 2
• Continue ipratropium every 6 hours 1, 2
• Arrange immediate hospital admission 1, 2

Escalation for Refractory Cases

If no improvement after 15-30 minutes:

• Increase nebulized salbutamol to every 15-30 minutes or consider continuous nebulization 1, 2
• Ensure ipratropium is added if not already given 1, 2
• Continue oxygen and systemic corticosteroids 1, 2

For life-threatening features:

• Give IV aminophylline 5 mg/kg over 20 minutes, followed by maintenance infusion 1 mg/kg/hour 1
• Do NOT give loading dose if child already on oral theophylline 1
• Prepare for ICU transfer 1, 2

Monitoring Throughout Treatment

• Chart PEF before and after β-agonist administration at least 4 times daily 1, 2
• Continuous pulse oximetry, maintain SpO₂ >92% 2
• Monitor for tachycardia (expected with β-agonists, but bradycardia is ominous) 1

Hospital Admission Criteria

Immediate admission required for:

• Any life-threatening features present 1, 2
• Features of severe attack persisting after initial treatment 1, 2
• PEF remaining <50% predicted after 1-2 hours of intensive treatment 2
• Parents unable to give appropriate treatment at home 2
• Failure to respond to or early deterioration after inhaled bronchodilators 1

Lower threshold for admission:

• Presentation in afternoon/evening 1
• Recent nocturnal symptoms 1
• Previous severe attacks 1
• Poor social circumstances or inadequate support 1

ICU Transfer Criteria

Transfer to intensive care unit if:

• Deteriorating PEF despite treatment 1, 2
• Worsening exhaustion or feeble respirations 1, 2
• Persistent or worsening hypoxia (SpO₂ <92%) or hypercapnia 1, 2
• Altered consciousness, confusion, or drowsiness 1, 2
• Respiratory arrest or coma 1, 2

Transfer must be accompanied by a doctor prepared to intubate. 1

Critical Pitfalls to Avoid

• Never administer sedatives of any kind—this is absolutely contraindicated and potentially fatal 1, 2
• Do not delay systemic corticosteroids while giving repeated albuterol doses alone 2
• Do not give aminophylline bolus to children already on oral theophyllines 1
• Do not rely on subjective assessment alone—always obtain objective measurements (PEF, SpO₂) 1
• Aminophylline should no longer be used in children at home 1

Discharge Planning (When Stable)

Discharge criteria:

• On discharge medication for 24 hours with verified inhaler technique 1
• PEF >75% predicted or best (if recorded) 1
• PEF diurnal variability <25% 1
• Minimal or absent symptoms 1

Discharge medications:

• Continue prednisolone 1-2 mg/kg daily for total 3-5 days 1, 2
• Inhaled corticosteroids in addition to bronchodilators 1
• Provide own PEF meter and written self-management plan 1

Follow-up:

• GP follow-up within 1 week 1
• Respiratory clinic follow-up within 4 weeks 1

Levosalbutamol vs Racemic Salbutamol

While the question specifically asks about "Levolin" (levosalbutamol), current international guidelines recommend racemic salbutamol as the standard bronchodilator for acute pediatric asthma. 1, 2

Research evidence suggests levosalbutamol may offer modest advantages:

• Greater improvement in SpO₂, PEFR, and asthma scores compared to racemic salbutamol 5, 6
• Less tachycardia and less hypokalemia than racemic salbutamol 5, 6

However, these studies are small and not incorporated into major international guidelines. 5, 6 The dosing, frequency, and escalation protocols described above apply to standard racemic salbutamol, which remains the evidence-based first-line treatment. 1, 2

If levosalbutamol is used, apply the same dosing schedule (typically half the mg dose of racemic salbutamol due to removal of the inactive S-isomer), frequency, and escalation protocols outlined above. 5, 6