Abstract
Facemasks serve as a patient-device interface to facilitate drug delivery from a pressurized metered dose inhaler (pMDI) with an attached valved holding chamber (VHC), and are capable of significantly affecting inhalation drug therapy. A novel horizontal test rig designed for the evaluation of facemask performance under simulated conditions was used to measure delivered dose from ProAir HFA pMDIs (108 μg albuterol sulfate/actuation, Teva Specialty Pharmaceuticals LLC). Three brands of VHC-facemask systems were tested: preproduction OptiChamber Diamond (Diamond) VHCs with preproduction LiteTouch facemasks (Philips Respironics), AeroChamber Plus Z Stat (Z Stat) VHCs with ComfortSeal facemasks (Monaghan Medical Corp.), and Vortex VHCs with Spinner Duck facemasks (PARI GmbH).
A face replica of a four-year-old child, with a replaceable aerosol filter in the “mouth”, was connected to a breathing simulator (ASL 5000; IngMar Medical Ltd) to simulate a pediatric breathing pattern (Vt=155 mL, f=25 bpm I:E=2:3). Each VHC-facemask system was naturally positioned against the face replica with a constant applied force supplied by a mass of 1.9 kg. Albuterol sulfate was quantified using HPLC after 1, 2, 4 and 8 “breaths” following pMDI actuation.
Table 1. Mean dose recovered on filter (%, n=3)
The delivered dose using the Diamond-LiteTouch system, after 1 breath, was significantly higher than the delivered dose using the Z Stat-ComfortSeal or the Vortex-Spinner Duck system after 8 breaths (p<0.01).
- © 2011 ERS
