Asthma Inhaler Technique - Amplified
Why Technique Matters
Drug delivery to the lungs depends on:
- Particle size (1-5 microns optimal)
- Inspiratory flow rate
- Breath-holding time
- Device technique
Poor technique → drug deposits in mouth/throat instead of lungs → reduced efficacy, increased side effects (thrush with ICS).
Studies show 50-80% of patients have suboptimal technique.
Device Types
pMDI (Pressurised Metered-Dose Inhaler)
- Propellant-driven aerosol
- Requires coordination (actuation-inhalation)
- Spacer eliminates coordination problem
- Always use with spacer in children <6 years
DPI (Dry Powder Inhaler)
- Breath-actuated (e.g., Turbuhaler, Accuhaler)
- Requires forceful inhalation
- Not suitable for <6 years or acute asthma
Nebuliser
- Continuous aerosol via mask or mouthpiece
- Used in acute severe asthma
- Equivalent to pMDI+spacer if technique is correct
Spacer Technique
Why Use a Spacer?
- Slows particle velocity → less oropharyngeal deposition
- Allows evaporation → smaller particles
- Eliminates need for coordination
- Increases lung deposition from 10% to 20%+
Standard Technique (Older Child/Adult)
- Shake MDI vigorously (redistributes propellant)
- Attach to spacer
- Sit or stand upright
- Breathe out gently (not fully)
- Seal lips around mouthpiece
- Press canister once
- Breathe in slowly and deeply
- Hold breath for 10 seconds
- Breathe out through nose
- Wait 30-60 seconds before next puff
Tidal Breathing (Young Child/Mask)
For children who can't do single-breath technique:
- Good mask seal (no gaps)
- Actuate once
- Leave mask in place for 4-6 breaths
- Watch for mist in spacer (indicates valve working)
Common Errors
| Error | Consequence |
|---|---|
| Not shaking | Inconsistent dose |
| Multiple puffs before breathing | Drug settles in spacer |
| Breathing in too fast | Oropharyngeal deposition |
| Not holding breath | Reduced absorption |
| Not waiting between puffs | Second dose less effective |
Practical Tips
For crying children:
- Wait until calm
- Crying = irregular breathing = poor delivery
- Distraction techniques help
Spacer care:
- Wash in soapy water monthly
- Air dry (don't wipe - static charge)
- Replace every 12 months
After ICS use:
- Rinse mouth and spit
- Prevents oral candidiasis
- Prevents systemic absorption from swallowed drug