Inspiratory flow rates at different levels of resistance in elderly COPD patients

Abstract

Dry powder inhalers (DPIs) are increasingly replacing metered dose inhalers in elderly chronic obstructive pulmonary disease (COPD) patients. However, most DPIs are dependent on inspiratory flow, which is compromised by the ageing process itself.Using the in-check dial method, the present study compared peak inspiratory flow (PIF) rates in 26 elderly COPD patients and 14 matched control subjects, at a pre-set resistance level of the Aeroliser1, Diskus1 and Turbuhaler1 inhalers.It was found that the PIF measured by the in-check method positively correlated with the PIF derived from spirometry, forced vital capacity and maximal inspiratory pressure, while a negative, but significant, correlation was observed with age. PIF derived from spirometry and age were independent variables which determined PIF across the device, whereas the presence or absence of COPD was not related. When comparing elderly COPD patients with matched elderly controls no difference could be found in PIF at the different resistances. However, an important number of patients did not reach the recommended flow rate, especially when using the Turbuhaler1 (30%).In conclusion, the present study demonstrates that, in elderly patients, the ability to generate sufficient inspiratory flow across a dry powder inhaler is compromised, irrespective of the presence of chronic obstructive pulmonary disease.

Inhaler technique: does age matter? A systematic review

“…Advanced age may also independently affect lung function and predict the ability to generate the peak inspiratory flow (PIF) rate required for optimal outcomes from certain DPIs, particularly the Turbuhaler, potentially affecting the type of error made [36,37]. As many as 75% of older adults may be unable to generate the minimum recommended PIF of 30 L·min −1 for a clinical response from the Turbuhaler [36], potentially leading to an inferior clinical response [38].…”

Drug Delivery from an Innovative LAMA/LABA Co-suspension Delivery Technology Fixed-Dose Combination MDI: Evidence of Consistency, Robustness, and Reliability

“…These flow rates were comparable with typical peak inspiratory flow rates of patients with COPD (13) and also produced a range of inhalation volumes since the MDI plume duration is constant regardless of the test flow rate. Moreover, peak inspiratory flow rates < 30 L/min are not common for patients with COPD, particularly using an MDI device (13,22), and therefore 15 L/min in these Table I, indicating minimal impact of inhalation flow rate on the GFF MDI in vitro aerosol performance. Overall, these results showed GFF MDI performance is consistent across a broad range of inspiratory flow rates.…”

Inhalasjonsmedisiner må brukes riktig

“…Dette gjelder for eksempel eldre og barn, og en studie viste at 30 prosent og 20 prosent av pasienter over 70 år hadde problemer med henholdsvis turbuhaler og diskus (13). Resultatene var uavhengig av om de hadde obstruktive lungelidelser eller ikke (13).…”

“…Dette er derfor viktig å ta med i betraktning når man skal velge inhalator for pasienten. Studier viser at turbuhaler har størst intern motstand, etterfulgt av diskus og handihaler, mens breezhaler har minst motstand av apparatene som er sammenliknet (1,13,14).…”