It is true that aerosol therapy needs to be individualized. However, this study has amply proved that in an acute attack of asthma even in severe cases one should not feel handicapped in the absence of a nebulizer. There are no doubt problems with the spacer as well and one needs to train the patient properly. Studies have shown that in an acute attack, flow required to trigger the valve may not be generated but contrary evidence is also available. Earlier work(1) has shown that pressure and flow required to open and close the valve in commercially available spacers are minimal and can be generated by small or sick infants. This problem can also be overcome by using a spacer without a valve, which can be effective(2). A home-made spacer can be used or a commercially available spacer when inverted activates the valve and can be used in a recumbant patient. Cleaning the spacer regularly will keep the valve nonsticky and operative at lower pressure.

We had mentioned the usual percent- age of aerosol that reaches the lung when a nebulizer is used. It is reported that even in six month old patients, the median percentage of drug delivered by nebulizer is 11 % while in eight years old it is 14%(3).

G.R. Sethi,
Vandana Batra,
Department of Pediatrics,
Maulana Azad Medical College,
 New Delhi 110 002, India.
 

1. Sennhauser FH, Sly PO. Pressure flow characteristics of the valve in spacer de- vices. Arch Dis Child 1989; 64: 1305-1319.

2. Levison H, Railly PA, Worsley GH. Spacing devices and metered dose inhalers in childhood asthma. J Pediatr 1985; 107: 662-668.

3. Bisgaard H. Aerosol treatment of young children. Eur Respir Rev 1994; 4: 15-20.