Paediatrics: Asthma: drug delivery devices

Asthma: drug delivery devices

There are a number of drug delivery devices that are available for use in children:

·  Nebulizer: use in emergency treatment at all ages for delivery of bronchodilator (although a spacer device is often used instead).

·  Large or small volume spacer with metered dose inhaler (MDI): use in infancy to any age (facemask for under 3yrs and mouthpiece for older children). This device uses a plastic ‘bubble’ with a valve at one end and a place where an MDI can be inserted at the other end. The spacer allows the aerosol particles from the inhaler to be slowed and inhaled on each breath. It stops the drug dose from the MDI depositing in mouth or stomach, and allows it to go with inspired air all the way down to the small airways.

·  Dry powder device: terbutaline sulphate (Bricanyl Turbohaler^®), salbutamol (Ventolin Accuhaler^®). These can be used in children >5yrs.

·  Propellant metered dose inhaler (PMDI): these can be used in children >12yrs, although are difficult to use and generally not advised. The device uses a gas propellant to aerosolize the drug.

Inhalation technique

In the clinic you will need to make sure that your patient is getting and taking the medication prescribed. In all children you will need to see that they have the appropriate technique and device for their age.

Child >3yrs

Look for 5-breath tidal volume breathing technique.

·  Stands to allow full use of the diaphragm.

·  Shake MDI.

·  Place MDI into spacer.

·  Place device in mouth.

·  Firm seal with mouth around mouthpiece.

·  Breathe in and out tidally: when good rhythm, activate device (only once).

·  Continue breathing 5 times.

·  If second dose is needed: then shake MDI and repeat as above.

Infant

Note that, if the infant is crying, less drug will be inhaled. Make sure that the person giving the medication:

·  Tilt the spacer so that the valve is open (in small volume device you do not need to tip as the valve is low resistance).

·  Let the infant take at least five breaths from each dose actuated.