Guérin C, Coussa M L, Eissa N T, Corbeil C, Chassé M, Braidy J, Matar N, Milic-Emili J
Respiratory Division, Hôpital Saint-Luc, Université de Montréal, Quebec, Canada.
J Appl Physiol (1985). 1993 Apr;74(4):1570-80. doi: 10.1152/jappl.1993.74.4.1570.
By use of the technique of rapid airway occlusion, the effects of inspiratory flow, volume, and time on lung and chest wall mechanics were investigated in 10 chronic obstructive pulmonary disease (COPD) patients mechanically ventilated for acute respiratory failure. We measured the interrupter resistance (Rint), which in humans reflects airway resistance; the additional resistances due to time constant inequality and viscoelastic pressure dissipations within the lungs (delta RL) and the chest wall; and the static and dynamic elastances of lung and chest wall. We observed that 1) static elastances of lung and chest wall in COPD patients were similar to those of normal subjects; 2) Rint of the lung was markedly increased and flow dependent in COPD patients, whereas Rint of the chest wall was negligible as in normal subjects; and 3) in COPD patients, delta RL was markedly increased at all inflation flows and volumes, reflecting increased time constant inequalities within the lungs and/or altered viscoelastic behavior. The results imply increased dynamic work due to Rint and delta RL and marked time dependency of pulmonary resistance and elastance in COPD patients.
通过运用快速气道阻塞技术，我们对10例因急性呼吸衰竭而接受机械通气的慢性阻塞性肺疾病（COPD）患者，研究了吸气流量、容积和时间对肺及胸壁力学的影响。我们测量了阻断器阻力（Rint），在人体中它反映气道阻力；因时间常数不均一以及肺内和胸壁内粘弹性压力耗散所导致的附加阻力（δRL）；以及肺和胸壁的静态及动态弹性。我们观察到：1）COPD患者肺和胸壁的静态弹性与正常受试者相似；2）COPD患者肺的Rint显著增加且与流量相关，而胸壁的Rint与正常受试者一样可忽略不计；3）在COPD患者中，所有充气流量和容积下的δRL均显著增加，这反映了肺内时间常数不均一性增加和/或粘弹性行为改变。结果表明，COPD患者中由于Rint和δRL导致动态功增加，且肺阻力和弹性具有显著的时间依赖性。
