AEROSOL DELIVERY TO WHEEZY INFANTS - A COMPARISON BETWEEN A NEBULIZERAND 2 SMALL-VOLUME SPACERS

Inhalation therapy for wheezy infants with either a nebulizer or a pre ssurized metered-dose inhaler (pMDI) through a spacer is common practi ce. The aim of our study was to compare aerosol delivery to wheezy inf ants from a nebulizer and from a pMDI via two small volume spacers. Tw enty wheezy infants (aged 4-12 months) were recruited. They inhaled sa lbutamol from a Pari-Baby(R) nebulizer, from a detergent-coated Babyha ler(R), and from a Nebuchamber(R) in random order. A filter was placed between the inhalation systems and the patients. The amount of salbut amol deposited on the filter was measured using an ultraviolet spectro photometer and was expressed as a percentage of the total nebulized or actuated doses. The mean total nebulized dose for the Pari-Baby(R) (1 030 mu g) was higher (P < 0.001) than the mean actuated dose from a pM DI for the Babyhale(R) (374 mu g) and for the Nebuchamber(R) (378 mu g ) Mean drug deposition on the filter was 40.2% (150 mu g) of the total actuated dose for the detergent-coated Babyhaler(R) and 40.7% (154 mu g) of the total actuated dose for the Nebuchamber(R). There was no si gnificant difference in drug deposition on the filter between the two spacers. Mean drug deposition on the filter was 25.3% (260 mu g) of th e total nebulized dose for the Pari-Baby(R) nebulizer. There was no we ight dependence in drug deposition on the filter for the two spacers, but, drug deposition increased with the subject's weight for the nebul izer. We have shown that aerosol delivery to wheezy infants from a pMD I through small volume spacers is effective and that a higher percenta ge of the total amount of salbutamol is delivered than from a nebulize r. The weight dependence in drug deposition for the nebulizer can be o f clinical relevance. (C 1997 Wiley-Liss, Inc.