A young boy using a valved holding chamber with a face mask to inhale aerosolised drugs. Note the close-fitting mask. This is essential as if there is a gap between the face and the mask the child will receive very little drug.

This animation shows the internal workings of the Aeroeclipse nebuliser. When compressed air is fed into the nebuliser from below it passes through a small hole. This causes the air to expand causing a negative pressure. However, the negative pressure produced is insufficient to pull fluid up from the chamber so no aerosolization takes place. However, when the patient breathes in from the device this causes a negative pressure in the nebuliser and the central column is pulled downwards. When it comes down it narrows the gap that the compressed air goes through, this increases the negative pressure (Bernoulli effect) as the driving gas is passing through a narrower space. This increase in negative pressure is sufficient to pull fluid up so it passes on top of the expanding driving gas from the compressor and is atomised. The main advantage of this nebuliser is that it only nebulises when the patient breathes in so is much more efficient that a conventional nebuliser

This is a different type of mesh nebuliser where the energy comes from a piezoelectric generator that pushes fluid through the mesh, that has thousands of small holes in it, to form aerosol particles.

This video shows one of the most underappreciated reasons for poor lung delivery using a nebuliser. The child is using a jet nebuliser and in the first part of the video is breathing in and out via her nose. You can spot this by the lack of deflection of the aerosol cloud. After training you can see she is mouth-breathing and inhaling drugs. A nose clip would help as would a nebuliser that only works as the patient breaths in.