HypAir FeNO: an electrochemical sensor

We would like to congratulate Alcázar-Navarrete et al. [1] on their paper which was published in a recent issue of the European Respiratory Journal . The authors observed that persistent exhaled nitric oxide fraction ( F eNO) values ≥20 ppb in clinically stable chronic obstructive pulmonary disease (COPD) outpatients are associated with a significantly higher risk of acute exacerbations of COPD (AECOPD). This kind of approach would certainly have significant consequences for the follow-up of COPD patients. HypAir FeNO is an electrochemical sensor; there is no chemiluminescence NO device