Clinical application of impulse oscillation system determining bronchodilator reversibility test in the children of different ages / 中国医师进修杂志

ABSTRACT

Objective To explotr clinical application of impulse oscillation system(IOS)determining bronchodilator reversibility test and the impact of age factor on positive values of bronchoddilator reversibility test in children.Methods Two hundred and fifteen patients during asthma attack were recruited randomly for this study.They were divided into three groups according to their age(4-7 year-old group,8-11 year-old group and 12-16 year-old group).Mensurated MEFV and IOS lung function.Carried on the bronchial dilation test with the results.Forced expiratory volume in first second(FEV1),the sensitivity and specificity of IOS parameters,total respiratory impedance(Zrs),respiratory resistance at 5 Hz(R5)and 20 Hz(R20),reactance at 5 Hz(X5)and resonant frequency(Fres)for diagnosing asthma at different improvement levels after inhalation of bronchedilator were calculated respectively through using FEV1 as a "sold standard"in the different age groups.Results After inhalation of bronchodilator,Fres,Zrs,R5,X5 and R20 of IOS were improved significantly.The improvement of X5 was the most obvious,however the decline of R20 was the lowest.The improving rate of Fres,Zrs,R5 had very significant difference in the three age groups(P＜0.01).It displayed that the age factor was very important impact factor on the improving rate of Fres,Zrs,R5,however the improving rate of X5 was on difference in the three age groups(P＞0.05).In the three age groups,there were significantly positive correlations between X5,R5,Zrs and FEV1(P＜0.01).there wash't correlations between R20 and FEV1 in the 4-7 year-old group and the 12-16 year-old group(P＞0.05).Furthermore,when an increase of FEV1 equaling to or greater than 15% was used as reference for positive bronchial reversibility,the improve rate of Fres,Zrs,R5,and X5 equaled to or greater than 13%,23%,17%,31%,respectively in 4-7 year-old group,18%,26%,25%,32%,respectively in 8-11 year-old group,25%,28%,28%,36%,respectively in 12-16 year-old group. Conclusions IOS can be used to assess bronchodilator reversibility test in children,and age factors should be paid attention.