The correct use of dry powder inhalers (DPI) crucially depends on the peak inspiratory flow (PIF) that the patient can generate when overcoming internal resistance of the inhaler device.
It has been shown that some patients cannot achieve sufficient peak inspiratory flows with some DPI's, especially in the elderly population. The In-check Dial device (Clement Clarke International Ltd, Harlow, UK) allows to measure these inspiratory flows for different pre-set resistances, representing different DPI's.
Study design: interventional, single center, single visit study
30 Severe asthmatics and 70 COPD patients will be recruited in the UZ Brussel respiratory outpatient clinic.
All participants will provide written informed consent.
Patients will perform:
* pre-bronchodilator spirometry for the measurement of PIFspiro as per European respiratory Society/American Thoracic Society (ERS/ATS) guidelines for standard lung function5 (part of routine clinical follow-up).
* 5 forced inspiratory manoeuvres using the In-check Dial device G16, set at 5 different resistances (performed in order of increasing resistance), yielding the PIFresist values for the different DPI's
