K. Malmstrom et al., Application and efficacy of the multi-dose powder inhaler, Easyhaler (R), in children with asthma, PEDIAT A IM, 10(1), 1999, pp. 66-70
With powder inhalers, optimal performance is dependent on the inspiratory f
low produced by the patient through the devices. The objective of this open
, non-randomized study was to evaluate the suitability of a new, multidose,
dry powder inhaler, the Easyhaler(R), for children with asthma. The peak i
nspiratory flow (PIF) through the Easyhaler (PIFEH) was measured with a pne
umotachograph in 120 asthmatic children aged 4-16 yr. The bronchodilatory e
ffect of 0.2 mg salbutamol through the Easyhaler was compared with that of
0.2 mg salbutamol through a metered dose inhaler (MDI) with a spacer, in 15
children with obstruction. The mean PIFEH was 56 l/min (range 22-83 l/min)
. The PIFEH correlated significantly with age, height, and absolute peak ex
piratory flow (PEF), but not with the level of obstruction (PEF percentage
of predicted, range 45-146%). Only four children (aged 5, 6, 10, and 16 yr)
had PIFEH values below 28 l/min, which has been shown in in vitro studies
to be the threshold for effective use of the Easyhaler. In 15 children with
PEF, < 85% of predicted bronchodilatory effects of 0.2 mg salbutamol throu
gh the Easyhaler and from an MDI-cum-spacer were equal. Most children aged
6-16 yr produce PIF values sufficient for the use of the Easyhaler. The gai
n of 0.2 mg salbutamol from the Easyhaler was equal to that from a new, unp
rimed, MDI with a spacer in children with asthma.