TY - JOUR T1 - Regional lung function in nonsmokers and asymptomatic current and former smokers JF - ERJ Open Research JO - erjor DO - 10.1183/23120541.00240-2018 VL - 5 IS - 3 SP - 00240-2018 AU - Barbara Vogt AU - Kathinka Deuß AU - Victoria Hennig AU - Zhanqi Zhao AU - Ingmar Lautenschläger AU - Norbert Weiler AU - Inéz Frerichs Y1 - 2019/07/01 UR - http://openres.ersjournals.com/content/5/3/00240-2018.abstract N2 - Electrical impedance tomography (EIT) is able to detect rapid lung volume changes during breathing. The aim of our observational study was to characterise the heterogeneity of regional ventilation distribution in lung-healthy adults by EIT and to detect the possible impact of tobacco consumption.A total of 219 nonsmokers, asymptomatic ex-smokers and current smokers were examined during forced full expiration using EIT. Forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and FEV1/FVC were determined in 836 EIT image pixels for the analysis of spatial and temporal ventilation distribution. Coefficients of variation (CVs) of these pixel values were calculated. Histograms and medians of FEV1/FVCEIT and times required to exhale 50%, 75%, 90% of FVCEIT (t50, t75 and t90) were generated.CV of FEV1/FVCEIT distinguished among all groups (mean±sd: nonsmokers 0.43±0.05, ex-smokers 0.52±0.09, smokers 0.62±0.16). Histograms of FEV1/FVCEIT differentiated between nonsmokers and the other groups (p<0.0001). Medians of t50, t75 and t90 showed the lowest values in nonsmokers. Median t90 separated all groups (median (interquartile range): nonsmokers 0.82 (0.67–1.15), ex-smokers 1.41 (1.03–2.21), smokers 1.91 (1.33–3.53)).EIT detects regional ventilation heterogeneity during forced expiration in healthy nonsmokers and its increase in asymptomatic former and current smokers. Therefore, EIT-derived reference values should only be collected from nonsmoking lung-healthy adults.EIT assesses the spatial and temporal distribution of lung function in adults without pulmonary disease, and detects its increased heterogeneity in former and current smokers compared with nonsmokers. EIT reference values should originate from nonsmokers. http://bit.ly/2wsJQWD ER -