Early and late effect of acute bronchodilation on exhaled nitric oxide in asthma

Abstract

Background: We showed that FENO remains stable, increases or decreases in asthma patients 20' min after salbutamol (SABA) inhalation depending on the site of bronchoconstriction relief: up to central, pre-acinar and intra-acinar airways respectively (A. Michils JACI-In press). This may impact the use of FENO in asthma management if these effects are prolonged all over the period of SABA action.Aim: To evaluate the FENO changes induced by SABA in asthma patients over 4 hours.Methods: FENO, FEV1, and the slope (S) of phase III of He, and SF6 from a single-breath test were measured in stable asthma patients (n=17)before and up to 4 hours after SABA (400µg). SHe and SSF6 decrease reflects pre- and intra-acinar obstruction relief respectively.Results: Patients (4F/13M, age: 51±18 years) were divided in groups with positive (FENO+, n=9) and negative (FENO-, n=8) FENO change at 20' after SABA inhalation, compared to baseline.info:eu-repo/semantics/publishe