脉冲振荡肺功能COPD气道阻力参数的评估及优化

目的：评估脉冲振荡（impulse oscillometry system,IOS）肺功能多种IOS阻力参数在慢性阻塞性肺疾病（chronic obstructive pulmonary disease,COPD）和对照人群肺功能评估中的应用价值,并探讨部分参数的优化方法。方法：按时间顺序选择在门诊行肺功能检查的患者153例,其中符合COPD诊断标准的患者47例（COPD组）和非COPD受试者106例（非COPD组）,应用德国耶格公司的Master Screen肺功能仪进行常规肺功能和IOS肺功能测定,比较两组患者常规肺功能和IOS肺功能参数的差异,分析IOS肺功能参数与常规肺功能参数,特别是与FEV1/FVC的相关性。结果：COPD组R5、R5%、R5-R20、（R5-R20）%和（R5-R20）%/R20%均高于非COPD组,差异有统计学意义（P〈0.05）,大气道阻力参数R20和R20%在两组之间差异无统计学意义（P〉0.05）。IOS肺功能参数中与FEV1/FVC相关者,按相关系数由低到高排列,分别为R5、R5%、R5-R20、（R5-R20）%和（R5-R20）%/R20%。非COPD组IOS肺功能参数与常规肺功能参数无显著相关性。结论：COPD患者的IOS小气道阻力参数显著高于非COPD患者,大气道阻力无显著差异。优化的参数（R5-R20）%/R20%对气流阻塞的评估价值高于目前常被使用的（R5-R20）%、R5-R20、R5%和R5。IOS肺功能参数,尤其是（R5-R20）%/R20%在判断是否存在COPD方面具有一定价值,但所有IOS通气参数在定量评估通气功能大小方面作用有限。

Evaluation and optimization of impulse oscillometry system parameters in the measurement of small airway resistance of COPD

Objective： To determine the effectiveness of impulse oscillometry system（ IOS） parameters in evaluating small airway resistance in chronic obstructive pulmonary disease（ COPD） patients and to discuss ways of optimization if necessary. Methods： 153 sequential visitors of out-patient department were included,among which47 were COPD patients and denoted as COPD group,while the remaining 106 were enrolled in the non-COPD group. Conventional and IOS pulmonary function tests were performed and values were compared between groups,including（ R5-R20） % /R20%,the new IOS parameter induced by us. In each group,the correlation of IOS parameters with conventional ventilation parameters,especially FEV1 /FVC was studied. Results： The IOS values R5,R5%,R5-R20,（ R5-R20） % and（ R5-R20） % /R20% were significantly higher（ P 〈 0. 05） in COPD group than in the non-COPD group while R20 and R20% showed no difference（ P 〉 0. 05）.（ R5-R20） % /R20%correlated better with FEV1 /FVC than other IOS values. In non-COPD group,IOS values had a negligible correlation with conventional pulmonary function values. Conclusion： The small airway related IOS values show there is a higher small airway resistance in COPD than non-COPD subjects. Among the parameters,（ R5-R20） % /R20% achieves the highest correlation with FEV1 /FVC,making it the best parameter among IOS values in describing small airway resistance. IOS seems to be more useful in determining the existence of COPD than grading the severity of airway obstruction.