Abstract
Rationale
When assessing simulated deposition of pMDIs, it is normal to use a Sinusoidal Inhalation (SI) profile, similar to tidal inhalation. However, in real-life some patients with a pMDI inhale rapidly straightaway, with peak flow near the start of manoeuvre, a Rapid Inhalation (RI) profile. This study examined the influence of inhalation profile on lung deposition with FP/FORM pMDI (flutiform®) using Functional Respiratory Imaging (FRI).
Methods
3D airway models of 6 asthma patients (mean FEV1 83%), treated with an ICS/LABA combination, were included. Total lung (TLD), central (C) and peripheral (P) airway deposition of FP/FORM were assessed using FRI. Simulations were performed with both SI and RI profiles, which were matched for the average flow rate (30L/min and 60L/min) and duration of inhalation (3s); actuation was timed with the start of inhalation.
Results
TLD and C/P ratios for both SI and RI profiles at 30 and 60L/min are shown in the table.
Conclusions
In vitro lung deposition was high with both profiles and both flow rates. Both SI and RI profiles resulted in mostly peripheral deposition although this was higher with SI profile, which may be more optimal for pMDIs. These data predict FP/FORM may provide high levels of lung deposition (∼40% and above) of nominal dose with both RI and SI profiles, when used optimally, with deposition throughout central and peripheral airways.
This study was funded by MundiPharma International.
- © 2014 ERS