[慢性阻塞性肺疾病患者静息和最大运动时肺泡-动脉血氧分压差的测量]

[Measurement of alveolar-arterial partial pressure of oxygen difference in patients with chronic obstructive pulmonary disease both at rest and during maximal exercise].

作者信息

Wang Hao-yan, Xu Qiu-fen, Ding Hai-ju, Xiao Yao, Liu Xin-xin, Fan Jing, Zhang Ling

机构信息

Department of Respiratory Disease, Beijing Anzhen Hospital, Capital University of Medical Sciences, Beifing 100029, China.

出版信息

Zhonghua Yi Xue Za Zhi. 2007 Dec 4;87(45):3192-5.

PMID:18399112

Abstract

OBJECTIVE

To investigate the change of alveolar-arterial partial pressure of oxygen (PO2) difference [P (A-a) O2)] at rest and during exercise in patients with chronic obstructive pulmonary disease (COPD).

METHODS

Cardiopulmonary exercise testing was performed in 47 COPD male patients aged (66 +/- 8) at stable stage to measure the oxygen uptake (VO2) and carbon dioxide output (VCO2) continuously in a breath-by-breath mode. Arterial blood samples were drawn both at rest and during maximal exercise. P(A-a) O2 is computed by the equation: PAO2-PaO2.

RESULTS

The PaO2 level during exercise was (89 +/- 14) mm Hg, a little bit, however, not significantly, lower than that at rest [(92 +/- 9) mm Hg, P = 0.506]. The PaCO2 during exercise was 43 +/- 3 mm Hg, significantly higher than that at rest (41 +/- 4 mm Hg, P = 0.003). The patients were divided into two groups according to lung diffusing capacity for carbon monoxide (DLco). There was a significant increase in P(A-a) O2 from (16 +/- 8) mm Hg at rest to (42 +/- 9) mm Hg during maximal exercise in the DLco < 80% group (P = 0.005); however, in the DLco >80% group the P(A-a) O2 level during maximal exercise was (26 +/- 6) mm Hg, not significantly different from that at rest [(20 +/- 6) mm Hg, P = 0.106]. The P(A-a)O2 level of the DLco <80% group during maximal exercise was (42 +/- 9) mm Hg, significantly higher than that at rest [(16 +/- 8) mm Hg, P = 0.005]. The P(A-a)O2 was significantly negatively correlated with the forced vital capacity (r= -0.581, P = 0.037) and DLco (r = -0.671, P = 0.012).

CONCLUSION

The increase in P (A-a) O2 during exercise in the COPD patients is mainly due to the limited diffusing capacity of the lung.

摘要

目的

探讨慢性阻塞性肺疾病（COPD）患者静息及运动时肺泡-动脉血氧分压差[P（A-a）O2]的变化。

方法

对47例稳定期COPD男性患者（年龄66±8岁）进行心肺运动试验，以逐次呼吸模式连续测量摄氧量（VO2）和二氧化碳排出量（VCO2）。在静息和最大运动时采集动脉血样本。P（A-a）O2通过公式PAO2-PaO2计算得出。

结果

运动时的PaO2水平为（89±14）mmHg，略低于静息时[（92±9）mmHg]，但差异无统计学意义（P=0.506）。运动时的PaCO2为43±3mmHg，显著高于静息时（41±4mmHg，P=0.003）。根据一氧化碳肺弥散量（DLco）将患者分为两组。DLco<80%组静息时P（A-a）O2为（16±8）mmHg，最大运动时显著升高至（42±9）mmHg（P=0.005）；然而，DLco>80%组最大运动时P（A-a）O2水平为（26±6）mmHg，与静息时[（20±6）mmHg]差异无统计学意义（P=0.106）。DLco<80%组最大运动时P（A-a）O2水平为（42±9）mmHg，显著高于静息时[（16±8）mmHg，P=0.005]。P（A-a）O2与用力肺活量显著负相关（r=-0.581，P=0.037），与DLco也显著负相关（r=-0.671，P=0.012）。