This study investigated the relation between fractional exhaled nitric oxide (FeNO), impulse oscillometry (IOS) and small airway function in 140 asthmatic patients (71 of them had small airway dysfunction).
Levels of FeNO, reactance area (AX), resonant frequency (Fres) and blood eosinophils were increased in small airway dysfunction group. FeNO, AX and Fres correlated with FEF25-75% values. A receiver operating characteristic (ROC) analysis showed that the combination of FeNO, AX and Fres had a greater area under the ROC curve (AUC) than each of them individually.
FeNO combined with IOS can better evaluate the small airway function in asthmatic patients.
Study on small airway function in asthmatics with fractional exhaled nitric oxide and impulse oscillometry. Liu L et al. Clin Respir J. 2016 Sep 8. doi: 10.1111/crj.12548. [Epub ahead of print]
The World Allergy Organization (WAO) Small Airways Working Group publishes a monthly "What's New?" summary and I have served as its editor since 2011. The summary features the top 3 asthma/small airways articles each month. The article above is a part of the project. The archive is here: http://www.worldallergy.org/small_airways_group/reviews/archive.php
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