Measurement of peak inhalation rates with an In-Check Meterto identify an elderly patient's ability to use a Turbuhaler

Dry powder inhalers are designed with resistance to airflow so that a respirable cloud of particles is generated during inhalation. Some of these devices require a certain inhalation rate to produce a consistent dose of respirable particles. The aim of the study was to determine the inhalation rate of elderly patients with chronic obstructive pulmonary disease (COPD) when they inhale through a Turbuhaler and assess the potential of the In-Check Meter to identify inhalation rates. Their peak inhalation rate using a normal inhalation, pre- and post-counselling, was measured using a Turbuhaler Trainer and an In-Check Meter. Spirometry was also measured. Seventy-four COPD patients with a mean (SD) age of 79.7 (8.4) years and forced expiratory volume in 1 sec (FEV1) 41.9 (12.8)% predicted. Pre-counselling 14 obtained a rate of <30 l min(-1) with the Turbuhaler Trainer, 31 from 30 to 40 min(-1), 23 between 40-60 l min(-1) and 6 > 60 l min(-1). The median (range) peak inhalation rates with the In-Check Meter were 50 (50-70), 70 (50-130), 100 (60-200) and 225 (200-250) l min(-1). Post-counselling 7, 16,41 and 10 achieved the respective peak inhalation rates using the Turbuhaler Trainer Similarly the In-Check inhalation rates were 50 (50-60), 70 (50-130), 90 (60-200) and 250 (200-270) l min(-1). The results highlight the potential of the In-Check Meter to identify patients' inhalation rates through dry powder inhalers.