COPD患者膜弥散和肺血管床容量的变化及支气管扩张剂的影响

目的:探索慢性阻塞性肺疾病(COPD)缓解期不同分级的患者膜弥散功能(Dm)和肺血管床容量(Vc)的变化,以及使用支气管扩张剂后通气功能改善对Dm和Vc的影响。方法:2001年7月至2004年2月COPD缓解期患者95例,分为4组,Ⅰ级8例,Ⅱ级47例,Ⅲ级34例,Ⅳ级6例,正常对照组35例。使用一口气法,测定弥散量(DLCO)、弥散率(KCO即DLCO/VA)、Dm、Vc。58例COPD患者予以做扩张试验,试验阳性和阴性者均再次测定DLCO、KCO、Dm、Vc。将各组间的测定值及扩张前后的结果进行比较。结果:COPD各组患者的Dm、DLCO、Vc及KCO均低于正常对照组,随着级别的增加,降低的程度均加大。COPDⅠ级患者的Vc和KCO显著低于对照组(P<0.05,P<0.01),COPDⅡ级、Ⅲ级及Ⅳ级患者的DLCO、KCO、Dm、Vc均显著低于对照组(P<0.01)。COPD各分级之间除Vc没有显著的差别(P>0.05)外,Dm、DLCO和KCO差异均有显著性(P<0.01)。支气管扩张试验阳性患者扩张试验前后的DLCO、Dm、Vc均无显著的改变(P>0.05)。结论:COPD患者通气功能逐渐恶化导致了弥散量的下降,Dm的持续降低贯穿于整个COPD的早、中、晚期,而Vc的持续下降则发生在COPD的早、中期。支气管扩张剂的使用没有通过通气/血流比的改变对弥散量、Dm、Vc产生影响。

Changes of membrane diffusing capacity and pulmonary capillary blood volume in chronic obstructive pulmonary disease patients of different stages and after bronchodilator inhalation

Objective:To assess the changes of the membrane diffusing capacity (Dm) and pulmonary capillary blood volume (Vc) in different stages of COPD and the effect of the bronchodilator inhalation on diffusing capacity (DLCO) and Dm in COPD patients.Method:95 stable COPD patients have been classified into 4 groups: Stage Ⅰ, Ⅱ,Ⅲ and Ⅳ according to EFV_1/FVC%, FEV_1% values, each with 8, 47, 34, 6 patients respectively. Diffusing capacity (DLCO), KCO(DLCO/V_A), Dm and Vc were measured in baseline and after bronchodilator inhalation test with single breathing method.Result:In stage Ⅰ group, Dm, Vc, DLCO and KCO are all lower than normal subject group, but only Vc and KCO have reached significance ( P <0.05, P <0.01). DLCO, KCO, Dm are progressively decreased from Stage Ⅰ group to Stage Ⅳ group, all these parameters are significantly lower in stage Ⅱ,Ⅲ,Ⅳ groups comparing with that of normal subject group ( P <0.01). Vc are also gradually decreased from stage Ⅰ group to Stage Ⅲ group, but not further decreased in Stage Ⅳ group, the value in this group is comparable with that of Stage Ⅰ,Ⅱ and Ⅲ ( P >0.05). No significant changes have been found in DLCO, Dm, and Vc after bronchodilator inhalation in Stage Ⅰ to Ⅲ groups.Conclusion:Dm is progressively reduced with the severity of COPD, but the same trend of Vc reduction discontinues further in stage Ⅳ. Bronchodilator inhalation does not affect DLCO, Dm, and Vc.