2000 OPEN FORUM Abstracts
DOSE OUTPUT COMPARISON OF PAPERBOARD AND PLASTIC HOLDING CHAMBERS
Scott A. Foss BS, Jean W. Keppel PhD, David T. Sladek CRTT, Thayer Medical Corporation, Tucson AZ
Background: This laboratory study compares the performance of two hand-held valved holding chambers for metered dose inhalers (MDIs): the LiteAire?, which is made of foldable paperboard, and the AeroChamber®, which is made of injection-molded plastic. Total dose output was measured for six drugs: Proventil® HFA, Serevent®, Alupent®, Flovent®, Vanceril®, and Tilade®. Method: Output of the MDI chamber went into a USP throat model, which fed into a filter. A Harvard Breathing Machine inhaled and exhaled through the system (filter, throat model and MDI device) at a rate of 5 breaths/min and a volume of 750 mL. Any medication inhaled through the device impacted on the filter for analysis. In all tests the MDI drug canister was actuated at the start of inspiration, and the amount of active ingredient collected in the filter was assayed by ultraviolet (UV) spectroscopy. Ten different devices of each brand were tested with each drug.
Results: The graph below shows the mean for each device/drug combination, in micrograms per dose. Error bars are one standard deviation.
Two-tailed t-tests with unequal variances were done; any differences between the averages would be considered statistically significant if p < 0.05.
Conclusions: For all six drugs, the LiteAire and the AeroChamber were statistically equivalent in total dose output, with p-values ranging from 0.053 for Serevent to 0.98 for Alupent. The comparable performance of paperboard and plastic devices has some significance because of the novel character of a dual-valved holding chamber made of paperboard. The portability and disposability of the LiteAire may increase patient compliance and thereby extend the benefits of a holding chamber to a wider population of MDI users. (See Original for Figure)