TY - JOUR T1 - Significance of the forced oscillation technique for evaluation of the bronchodilation test in patients with initial mild airway obstruction JF - European Respiratory Journal JO - Eur Respir J DO - 10.1183/13993003.congress-2020.160 VL - 56 IS - suppl 64 SP - 160 AU - Elena M Zhukova AU - Lyudmila Vokhminova Y1 - 2020/09/07 UR - http://erj.ersjournals.com/content/56/suppl_64/160.abstract N2 - Aim: To evaluate the significance of the forced oscillation technique (FOT), allowing to measure respiratory impedance (RI), in the evaluation of bronchodilator test in patients with pulmonary tuberculosis with initial mild airway obstructionMethods: Indicators of forced flow-volume spirometry (FS FV) and FOT before and after inhalation of Fenoterol (F) were studied in a bronchodilator test. RI at the frequency of 8,12,16 Hz were determined: Rfo -RI in respiratory volume, Rin -RI at the inspiration level, Rex -RI at expiration one. The RI data were studied in the Group 1 of healthy people (n=22), the reproducibility and normal values of these parameters were established, as well as the changes in RI in healthy persons after inhalation with F during bronchodilator test. The Group 2 (group without ventilation disorders according to the results of FS FV) included 32 patients with mild airway obstruction, which was diagnosed only by FOTResults: Based on RI data, additional criteria were established for evaluating the test with bronchodilator. In Group 2: FS FV indicators of were normal and did not change after inhalation of F. After inhalation of F in Group 2 patients, FOT demonstrated a decrease in RI, a decrease in the number of pathological changes in RI and the frequency dependence of RI. Also, after inhalation of F, there was a positive dynamics of RI in 75% of patients, including 50% - in which RI indicators became completely normal. Thus, the one of the leading pathogenic mechanisms of mild airway obstruction is the bronchospasm.Conclusion: The use of FOT made possible to diagnose a bronchospasm in 50% of patients with mild airway obstruction.FootnotesCite this article as: European Respiratory Journal 2020; 56: Suppl. 64, 160.This abstract was presented at the 2020 ERS International Congress, in session “Respiratory viruses in the "pre COVID-19" era”.This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only). ER -