Aerosol delivery to wheezy infants: a comparison between a nebulizer and two small volume spacers.

Inhalation therapy for wheezy infants with either a nebulizer or a pressurized metered-dose inhaler (pMDI) through a spacer is common practice. The aim of our study was to compare aerosol delivery to wheezy infants from a nebulizer and from a pMDI via two small volume spacers. Twenty wheezy infants (aged 4–12 months) were recruited. They inhaled salbutamol from a Pari-Baby® nebulizer, from a detergent-coated Babyhaler®, and from a Nebuchamber® in random order. A filter was placed between the inhalation systems and the patients. The amount of salbutamol deposited on the filter was measured using an ultraviolet spectrophotometer and was expressed as a percentage of the total nebulized or actuated doses. The mean total nebulized dose for the Pari-Baby® (1030 μg) was higher (P < 0.001) than the mean actuated dove from a pMDI for the Babyhaler® (374 μg) and for the Nebuchamber® (378 μg). Mean drug deposition on the filter was 40.2% (150 μg) of the total actuated dose for the detergent-coated Babyhaler® and 40.7% (154 μg) of the total actuated dose for the Nebuchamber®. There was no significant difference in drug deposition on the filter between the two spacers. Mean drug deposition on the filter was 25.3% (260 μg) of the total nebulized dose for the Pari-Baby® nebulizer. There was no weight dependence in drug deposition on the filter for the two spacers, but, drug deposition increased with the subject's weight for the nebulizer. We have shown that aerosol delivery to wheezy infants from a pMDI through small volume spacers is effective and that a higher percentage of the total amount of salbutamol is delivered than from a nebulizer. The weight dependence in drug deposition for the nebulizer can be of clinical relevance. Pediatr Pulmonol. 1997; 23:212–216 © 1997 Wiley-Liss, Inc.