What is the proper preparation and administration of nebulised salbutamol (albuterol)?

How to Prepare Nebulised Salbutamol

For acute asthma or COPD exacerbations, prepare nebulised salbutamol by diluting the appropriate dose (2.5-5 mg for adults, 0.15 mg/kg or 5 mg for children) in a minimum total volume of 3 mL using normal saline, and deliver via oxygen-driven nebulizer at 6-8 L/min flow rate. 1

Standard Preparation Protocol

Dosing by Patient Population

Adults:

• Standard dose: 2.5-5 mg salbutamol nebuliser solution 1
• Acute severe asthma: 5 mg every 20 minutes for 3 doses, then 2.5-10 mg every 1-4 hours as needed 1
• COPD exacerbations: 2.5-5 mg every 4-6 hours for 24-48 hours or until clinically improving 1

Children:

• Weight-based: 0.15 mg/kg (minimum 2.5 mg) 1
• Standard pediatric dose: 5 mg every 20 minutes for 3 doses in acute severe asthma 1
• For children under 5 years, consider starting with half doses 2

Infants:

• 2.5 mg diluted in 2-3 mL normal saline every 20 minutes for up to 3 doses during acute bronchospasm 3

Dilution Requirements

Critical preparation steps:

• Always dilute to a minimum total volume of 3 mL using normal saline (0.9% NaCl) 1, 2
• Never use water as a diluent, as it can cause paradoxical bronchoconstriction in some patients, particularly infants 4
• While one study showed water dilution may not significantly reduce bronchodilator response in adults 5, normal saline remains the standard of care to avoid hypotonic-induced bronchoconstriction 4

Nebulizer Setup and Delivery

Equipment configuration:

• Use oxygen as the driving gas at 6-8 L/min flow rate whenever possible, especially in acute severe asthma 1
• For COPD patients with carbon dioxide retention and acidosis, use air-driven nebulization (not high-flow oxygen) to avoid worsening hypercapnia 1
• Large volume nebulizers should be used for continuous administration if required 1

Administration technique:

• Ensure proper face mask fit for infants and young children who cannot use mouthpieces 3
• For children over 4 years, a mouthpiece is preferred over face mask 1
• Treatment typically takes 5-10 minutes to complete nebulization 1

Combination Therapy Preparation

When to add ipratropium bromide:

• In acute severe asthma with poor initial response to salbutamol alone 1
• Mix ipratropium bromide 250-500 μg directly with salbutamol in the same nebulizer chamber 1, 6
• For adults: add 500 μg ipratropium to salbutamol 1
• For children: add 250 μg ipratropium to salbutamol 1

Frequency and Monitoring

Treatment intervals:

• Acute severe cases: every 20 minutes for first 3 doses 1
• If improving: reduce to every 1-4 hours as needed 1
• Chronic stable disease: typically 4-6 hourly 1

Important monitoring parameters:

• Peak flow rate before and 30 minutes after treatment 1
• Heart rate, respiratory rate, oxygen saturation 3
• Watch for tachycardia, tremor, and palpitations as dose-related side effects 7

Critical Pitfalls to Avoid

Common errors in preparation:

• Do not use undiluted salbutamol solution - always ensure minimum 3 mL total volume 1, 2
• Do not use water as diluent - use only normal saline to prevent paradoxical bronchoconstriction 4
• Do not use oxygen-driven nebulization in COPD patients with CO2 retention - use air-driven instead 1
• In elderly patients, supervise first treatment as beta-agonists may rarely precipitate angina 1

Equipment maintenance:

• Nebulizer chambers and masks must be cleaned regularly to prevent medication buildup and bacterial contamination 8
• Ensure nebulizer is functioning properly before each use 1

Special Considerations

Dose optimization:

• Research suggests 3 mg may be an optimal dose for adults, providing satisfactory bronchodilation with fewer systemic side effects compared to higher doses 7
• However, current guidelines recommend 2.5-5 mg for acute exacerbations based on severity 1
• Patients with peak flow <140 L/min gain maximum benefit from combination therapy with ipratropium 9

Alternative delivery:

• Metered dose inhaler with spacer is equally effective as nebulizer for mild-to-moderate exacerbations when used with appropriate technique, typically requiring 1/4 of the nebulizer dose 10
• Consider MDI with spacer (4-8 puffs every 20 minutes) as alternative if nebulizer unavailable 1