Facemasks and aerosol delivery by metered dose inhaler-valved holding chamber in young children: a tight seal makes the difference.
A facemask on a valved holding chamber (VHC) facilitates the inhalation of aerosols from metered dose inhalers (MDI) for young children. Only recently the facemask has been recognized as a vital part for efficient aerosol delivery. Several in vitro and in vivo studies show that a tight seal of the facemask is crucial for optimal aerosol deposition to the lungs. Even a small leak can reduce the dose delivered to the lungs considerably. However, a tight seal is difficult to obtain when a child is not cooperative. Depending on the design of the facemask, it is easier to obtain a good seal. Factors such as dead space, shape, and material should be considered when designing a facemask. However, when a child is upset and not cooperative during the administration, aerosol deposition will be minimal, even with the best-designed facemask.
Janssens
H M
HM
Department of Pediatric Pulmonology, Erasmus Medical Center, Sophia Children's Hospital, Rotterdam, The Netherlands. H.Janssens@erasmusmc.nl
Tiddens
H A W
HA
D000336:Aerosols / Q000008:administration & dosage*; D002675:Child, Preschool; D004867:Equipment Design; D004868:Equipment Failure; D006801:Humans; D008397:Masks; D036501:Metered Dose Inhalers; D010349:Patient Compliance
D000336:Aerosols