稳定期COPD患者肺膜弥散和肺毛细血管床容量的改变

Pulmonary membrane diffusing capacity and pulmonary capillary blood volume in patients with stable COPD

目的研究不同病程慢性阻塞性肺疾病(COPD)肺弥散功能的改变,探讨肺泡毛细血管膜弥散能力(Dm)与肺毛细血管床容量(Vc)对COPD病情评估的意义。方法对38例稳定期COPD患者和35例健康者测定静息状态下的肺通气功能和弥散功能,观察各项肺功能参数的变化情况。结果COPD组的第一秒用力呼气容积(FEV1)占预计值百分比、FEV1/用力肺活量(FVC)、最大通气量(MVV)占预计值百分比等参数从Ⅰ级开始较对照组明显下降;肺一氧化碳弥散量(DLCO)、每升肺泡容积DLCO(DLCO/VA)、Dm以及Vc等参数则从Ⅱ级开始较对照组明显下降;Ⅰ级患者Dm较对照组下降,但Vc有增高(均P<0.05)。结论在COPD早期,尽管DLCO值在正常范围,但膜弥散已有损害,随着病情的进展,Dm和Vc同时减低,DLCO下降的速度明显加快。Dm及Vc是弥散功能重要和敏感的指标,可反映肺组织的结构和病理生理改变,有重要的临床应用价值。

Objective To study the clinical significance of pulmonary membrane diffusing capacity（Dm） and pulmonary capillary blood volume （Vc） in patients with stable chronic obstructive pulmonary disease （COPD）. Methods Spirometry was performed in 38 patients with stable COPD and 35 healthy individuals in resting condition. The changes of pulmonary parameters were obtained and compared between groups. Results Spirometry test revealed that the percent predicted forced expired volume in one second （ FEV1 ） , FEV1/forced volume capacity（FVC） and the percent predicted maximal ventilatory volume （MVV） were declined from stage Ⅰ in patients with COPD in comparison with healthy individuals, while diffusing capacity for carbon monoxide of lung （ DLCO） , carbon monoxide diffusing capacity per liter of alveolar （ DLCO/VA） ,Dm and Vc were declined from stage Ⅱ .Dm in patients with COPD of stage Ⅰ was significantly decreased compared with the controls, while Vc was increased compared with the controls （ both P 〈 0.05 ）. Conclusion Although DLCO may be normal, the change in Dm can be found in patients with COPD in the early stage. Both Dm and Vc are impaired later, and DLCO is significantly declined. Dm and Vc are important and sensitive for monitoring pulmonary diffusing function in patients with COPD, and can be helpful in detecting pulmonary involvement in patients with COPD.