Assessment of inspiratory flow in bronchial asthma by using a portable meter

The use of inhalation systems for the administration of specific drugs allows the selective treatment of asthma through the respiratory tract, which affords a higher drug concentration in the target tissue and lesser systemic exposure. It is therefore important to know the quality of inspiratory flow in patients with asthma who are subjected or amenable to treatment because, in the case of dry powder inhalers (DPIs), the flow must be higher than in the case of pressurized canister inhalers.

To evaluate the mean inspiratory flow (L/min) in such patients.

A total of 2387 Spanish patients were included in a cross-sectional, multicenter, noninterventional epidemiologic study. Inspiratory flux measurements were made, and the Asthma Control Test, Airways 20, and Morisky-Green questionnaires were used.

The mean (standard deviation) inspiratory flow value measured was 72.39 ± 25.04 L/min, and the value was <60 L/min in 29.8% of the patients. The DPI was the most widely used device among the patients in the study (61.4%), although no significant difference was observed between DPI and metered dose inhaler devices in previous studies demonstrated no significant differences between DPI and metered dose inhaler devices in efficacy and safety profiles. Significant differences were recorded according to patient age and weight. Although this was not an objective data analysis it presented interesting results for discussion.

Before selecting the inhalation system, and especially in older patients and in individuals who are overweight or sedentary, it is very important to ensure that the inspiratory flow is sufficient to guarantee optimal drug deposition to improve asthma control and thus patient quality of life.