肺弥散功能指标DLco、Kco在肺疾病诊断中应用价值的探讨

为了进一步了解各有关因素对肺弥散功能DLco及Kco测定的影响以及二者测定在航天医学中应用的可行性.本实验采用一口气法对120例健康人和76例肺疾病患者进行了肺弥散功能和常规肺功能测定,并作了对比分析.结果表明,健康人DLco、Kco均值随年龄增加而递减.DLco男性大于女性,与身高呈正相关,随肺容量(VC、TLC)增加而增加.Kco不受身高、性别及肺容量的影响,但随FEV_1的百分数增加而增加,随RV的百分数的增加而减少.在健康人中,虽然肺容量、通气量对DLco、Kco的影响有差异,但二者所占预计值的百分比基本相同.说明在健康人中二者的变化是同步的.在各种肺疾病中,二种指标均有下降.但在阻塞性肺疾病中以Kco反应敏感,可作为早期诊断肺气肿的指标.在限制性肺疾病中,以DLco下降更显著,说明在不同肺疾病中二者的反应是有差别的.这两项指标既有相关性,又各具特点.二者结合起来分析,对于航天医学中正确判断肺弥散障碍发生的环节,对于潜在性疾病的早期诊断和鉴别具有实用价值.

Inquiry on Pulmonary Diffusion Function Indices of DLco and Kco as Applied in Diagnosing Pulmonary Diseases

A study was made on the effects of relevant factors on pulmonary diffusion function and applicability of diffusion measurements in space medicine. In this experiment, diffusion measurements were made using single breath method in 120 healthy subjects and 76 patients with lung diseases. A comparative analysis was also made. The results showed that DLco and Kco in healthy subjects decreased with age. While DLco was found to be higher in male than female, positively correlated with body height, and increased with increase of VC and TLC. Kco was not affected by body height, sex or lung volume, but increased with increased percentage of FEV1 and decreased with increased percentage of RV. Although the effects of pulmonary capacity and ventilation on DLco and Kco are different, their percentages in the predicted values are similar. It showed that their changes in healthy subjects are synchronous. Both of the two parameters decreased in various pulmonary diseases. However, Kco had a sensitive response in chronic obstructive pulmonary diseases, which may be used as an index for early diagnosis of pulmonary emphysema. DLco decreased remarkably in restructive pulmonary diseases. It indicates that the two indexes of diffusion capacity respond differently to different pulmonary diseases. It may be helpful when these two parameters of pulmonary diffusion are used in combination in determining impairment in diffusion capacity for early diagnosis of pulmonary diseases.