Correlations Between Lung Function And Respiratory Impedance By Impulse Oscillometry In Patients With Chronic Obstructive Pulmonary Disease(COPD)

0bjective :To assess the correlations between ventilation function and respiratory impedance in patients with COPDMethod :The IOS indices of 51 cases of COPD and 12 normal cases were measured and compared with the indices of pulmonary ventilation function test and lung capacity testResults : Compared with the normal cases,there was a significant decrease in FEV1,FEV1/pre%,FEV1/FVC in 51 cases of COPD(P<0.05)。FEV1,FEV1/pre%,FEV1/FVC got worse with development of the disease(P<0.05)。The IOS indices except X5,X5/pre increased significantly in COPD group compared with the normal cases(P<0.05)。There were significant difference in the IOS indices including ZRS,ZRS/pre,R5,R5/pre,X5,X5/pre betweenⅢ,Ⅳstage COPD andⅠ,Ⅱstage COPD(P<0.05),and there was no significant difference betweenⅢstage COPD andⅣstage COPD.Fres got worse with development of the disease(P<0.05).There was no significant difference between all stage COPD. ZRS,R5,Fres were negatively correlated with FEV1/pre,FEV1/FVC,reversely,X5 was positively correlated(P<0.05 ) .The closest correlation was found between Fres and FEV1/pre %(r=0.666).There was no significant correlation between R20 and ventilation function(P>0.05).Conclusions :IOS can reflect the genius morbid of COPD which are increasing of airway resistance and hyperinflation of periphery lung tissue,had a good correlation with ventilation function. IOS is of value in clinic.