RATIONALE
This FRI based study assessed the modelled airway drug delivery from an MDI/spacer system and two DPI systems at optimal and sub optimal flow rates.
METHOD
Three-dimensional geometries of airways and lobes were extracted from a CT scan of a 67 year old male COPD (Gold III) patient.
Device Tested
The aerodynamic particle size distribution (APSD) profiles and delivered doses were obtained from published data.
Inhalation flow rates of 30 L/min (optimum for MDI/VHC, sub optimal for 2 DPIs) and 60 L/min (optimum for 2 DPIs, sub optimal for MDI/VHC) were assessed.
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RESULTS
Expressed as a percentage of labelled metered doses (average values used when more than one drug in combination)
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Modelled Lung Deposition (average values used when more than one drug in combination)
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CONCLUSION
- The FRI deposition profiles highlight that the MDI/AeroChamber Plus* Flow-Vu* VHC delivered a significantly greater percentage of drug to the lung region than either of the two DPIs, irrespective of flow rate.
- This was reflected in much higher modelled oropharyngeal deposition for the two DPIs.
- The influence of inhalation flow profile was significant for one of the DPIs.