Stewart R I, Lewis C M
S Afr Med J. 1985 Nov 9;68(10):746-8.
In this preliminary study 20 patients with chronic obstructive pulmonary disease (COPD) walked on the treadmill until symptoms limited further exercise. When minute volume exceeded 60% of the predicted maximum breathing capacity the arterial carbon dioxide partial pressure was frequently low, thus indicating hyperventilation; the arterial oxygen partial pressure also declined on exercise. In only 2 patients was there alveolar hypoventilation. Although other factors may be operative, the hyperventilation in some patients with COPD may be induced by an exertional decline in alveolar oxygen partial pressure. In 4 patients the exercise tidal volume exceeded the resting inspiratory capacity, indicating a decline in functional residual capacity and increased work of breathing. It is concluded that there is a need further to assess patients with COPD in respect of the association between exertional dyspnoea, alveolar ventilation and lung mechanics.
在这项初步研究中，20名慢性阻塞性肺疾病（COPD）患者在跑步机上行走，直至症状限制了进一步运动。当每分通气量超过预测最大呼吸能力的60%时，动脉血二氧化碳分压常降低，提示存在过度通气；运动时动脉血氧分压也下降。仅2例患者存在肺泡通气不足。虽然可能还有其他因素起作用，但部分COPD患者的过度通气可能由运动时肺泡氧分压下降所致。4例患者运动时潮气量超过静息吸气容量，提示功能残气量降低及呼吸功增加。结论是，有必要进一步评估COPD患者运动性呼吸困难、肺泡通气与肺力学之间的关系。
