Influence of inhalation profile on deposition in COPD and Asthma patients

<bold>Background:</bold> Inhaled medication is a cornerstone in treatment of Asthma and COPD. When measuring patients’ inhalation profiles, they reach peak inspiratory flows (PIF) of over 140 l/min, while guidelines recommend 30 l/min (Laube et al., 2011). <bold>The aim of this study</bold> is to investigate the effect of inhalation profile by using pressurized metered-dose inhaler (pMDI) without spacer, on deposition of drug in the lungs and teach patients the most effective way of inhalation therapy. <bold>Methods:</bold> Deposition of fine particle LABA + ICS delivered via pMDI, in 50 healthy volunteers, 50 asthma patients and 50 COPD patients was calculated by Rapid Deposition Analysis. Three inhalation profiles were measured: PIF of 40 l/min; PIF of 140 l/min and idealized PIF of 32 l/min (Fig 1). <bold>Results:</bold> The idealized flow delivers the highest intrathoracic and peripheral deposition (PD). Comparing PIF of 40 L/min and 140L/min, PD is 1.6 times higher for the slow flow. In high PIF, carina of trachea seems to be the most affected zone. Influence of flow is consistent for the three populations, with slightly lower effect on COPD (Fig 1). <bold>Conclusions:</bold> The inhalation profile, and more specific the PIF, has a significant effect on the peripheral deposition of the drug. PIF of 30 L/min has most effective peripheral drug deposition. Patients should be taught to exhale until residual capacity and inhale slowly to total lung capacity, during 3–5 seconds to reach the best PD. <fig><object-id>erj;64/suppl_68/PA747/F1</object-id><object-id>F1</object-id><object-id>F1</object-id><graphic></graphic></fig>