Study Of Clinical Application Value Of Impulse Oscillometry In Chronic Obstructive Pulmonary Disease

[Objective] To investigate the clinical application value of impulse oscillometry in COPD.[Method] The IOS indices of 154 cases of COPD and 60 normal cases were measured and compared with the indices of pulmonary ventilation function test and lung capacity test,in which pulmonary function of 30 cases of COPD were measured and analyzed both in exacerbation and stable stage.[Results] Compared with the normal cases, there was a significant decrease in FVC/pre,FEV1/pre,FEV1/FVC in 106 cases of COPD (P<0.05). The IOS indices including Fres,Z5/pre,R5/pre,R20/pre,R5-R20/pre increased significantly but X5 decreased significantly in COPD group compared with the normal cases(P<0.05), Z5/pre,R5/pre and R5-R20/pre got worse with development of the disease. Fres Z5/pre,R5/pre and R5-R20/pre were negatively correlated with FVC/pre,FEV1/pre,FEV1/FVC, reversely, X5 was positively correlated(P<0.05). There were characteristic changes of IOS graphics in COPD. There was no significant difference in FVC/pre,FEV1/pre,FEV1/FVC between 48 cases of 0 stage COPD and normal cases(P>0.05). There was a significant decrease in MEFV curses indices including FEF75/pre and FEF50/pre in 0 stage of COPD compared with normal cases(P<0.05). Compared with normal cases, Fres,Z5/pre,R5/pre and R5-R20/pre decreased significantly decreased but X5 increased significantly(P<0.05). ROC curves indicated that IOS indices could discriminate 0 stage of COPD group and normal group and the diagnosis accuracy rating was middling. Pulmonary function were measured in 30 cases of COPD both in exacerbation and stable stage and the result were as follow: the indices of lung ventilation including FVC,FVC/pre,FEV1,FEV1/pre and FEV1/ FVC increased significantly in stable stage compared with exacerbation(P<0.05). The indices of lung capacity including ITGV and RV significantly decreased in stable stage compared with exacerbation but IC increased significantly(P<0.05). The indices of IOS including Fres,Z5,R5,R20 and R5-R20 decreased significantly in stable stage compared with exacerbation, but X5 increased significantly(P<0.05). The improvement of lung capacity indices including IC,RV and ITGV were correlated with that of FVC (P<0.05), the improvement of IC and RV were correlated with that of FEV1 (P<0.05). The improvement of IOS indices including Z5,R5,R5-R20,X5 and Fres were correlated with those of FVC,FEV1 and FEV1/FVC (P<0.05).[Conclusions] IOS can reflect the genius morbid of COPD which are increasing of airway resistance and hyperinflation of periphery lung tissue, especially which is sensitive to the disfunction of small airway in early COPD, so IOS is of value for the diagnosis of COPD in clinic. IOS can also be used to observe dynamic change of lung function in different curses of COPD, which is helpful to understand the mechanism and characteristics of dynamic changes of pulmonary function in different courses of COPD.