Peslin R, Duvivier C
Unité 14 de Physiopathologie Respiratoire, Institut National de la Santé et de la Recherche Médicale, Université H. Poincaré Nancy I, Vandoeuvre-les-Nancy, France.
J Appl Physiol (1985). 1998 Feb;84(2):553-61. doi: 10.1152/jappl.1998.84.2.553.
We have tested the feasibility of separating the airway (Zaw) and tissue (Zti) components of total respiratory input impedance (Zrs,in) in healthy subjects by measuring alveolar gas compression by body plethysmography (Vpl) during pressure oscillations at the airway opening. The forced oscillation set up was placed inside a body plethysmograph, and the subjects rebreathed BTPS gas. Zrs,in and the relationship between Vpl and airway flow (Hpl) were measured from 4 to 29 Hz. Zaw and Zti were computed from Zrs,in and Hpl by using the monoalveolar T-network model and alveolar gas compliance derived from thoracic gas volume. The data were in good agreement with previous observations: airways and tissue resistance exhibited some positive and negative frequency dependences, respectively; airway reactance was consistent with an inertance of 0.015 +/- 0.003 hPa.s2.l-1 and tissue reactance with an elastance of 36 +/- 8 hPa/I. The changes seen with varying lung volume, during elastic loading of the chest and during bronchoconstriction, were mostly in agreement with the expected effects. The data, as well as computer simulation, suggest that the partitioning is unaffected by mechanical inhomogeneity and only moderately affected by airway wall shunting.
我们通过在气道开口处进行压力振荡期间利用体容积描记法（Vpl）测量肺泡气体压缩，测试了在健康受试者中分离总呼吸输入阻抗（Zrs,in）的气道（Zaw）和组织（Zti）成分的可行性。强迫振荡装置置于体容积描记器内，受试者呼吸BTPS气体。在4至29赫兹范围内测量Zrs,in以及Vpl与气道流量（Hpl）之间的关系。通过使用单肺泡T型网络模型以及从胸内气体容积得出的肺泡气体顺应性，根据Zrs,in和Hpl计算出Zaw和Zti。数据与先前的观察结果高度一致：气道和组织阻力分别呈现出一些正的和负的频率依赖性；气道电抗与0.015±0.003 hPa·s2·L-1的惯性一致，组织电抗与36±8 hPa/L的弹性一致。在不同肺容积时、胸部弹性负荷期间以及支气管收缩期间所观察到的变化，大多与预期效应相符。数据以及计算机模拟表明，这种划分不受机械不均匀性的影响，仅受到气道壁分流的适度影响。
