Bates J H, Ludwig M S, Sly P D, Brown K, Martin J G, Fredberg J J
Meakins-Christie Laboratories, McGill University, Montreal, Quebec, Canada.
J Appl Physiol (1985). 1988 Jul;65(1):408-14. doi: 10.1152/jappl.1988.65.1.408.
The interrupter method for measuring respiratory system resistance involves rapidly interrupting flow at the mouth while measuring the pressure just distal to the point of interruption. The pressure signal observed invariably exhibits two distinct phases. The first phase is a very rapid jump, designated delta Pinit, which occurs immediately on interruption of flow. The second phase is designated delta Pdif and is a further pressure change in the same direction as delta Pinit but evolving over several seconds. The physiological interpretations of delta Pinit and delta Pdif have been somewhat unclear. Delta Pinit has been taken to equal the pressure drop across the pulmonary airways, possibly with a contribution from the tissues of the respiratory system. Delta Pdif can arise, in principle, from two sources: gas redistribution throughout the lung after interruption of flow and stress recovery within the tissues. To resolve these issues we performed interruption experiments on anesthetized paralyzed, tracheotomized, open-chest normal dogs during passive expiration while measuring alveolar pressures at three sites with alveolar capsules. We found that, in the absence of the chest wall, delta Pinit reflects only the resistance of the airways and that delta Pdif can be ascribed almost entirely to the stress recovery properties of lung tissues.
测量呼吸系统阻力的阻断法是在口腔处快速阻断气流的同时，测量阻断点远端的压力。观察到的压力信号总是呈现出两个不同的阶段。第一阶段是一个非常快速的跃升，称为ΔPinit，它在气流阻断后立即出现。第二阶段称为ΔPdif，是与ΔPinit相同方向的进一步压力变化，但在数秒内逐渐变化。ΔPinit和ΔPdif的生理学解释一直有些不清楚。ΔPinit被认为等于肺气道上的压力降，可能呼吸系统组织也有一定贡献。原则上，ΔPdif可能源于两个来源：气流阻断后肺内气体的重新分布以及组织内的应力恢复。为了解决这些问题，我们在麻醉、麻痹、气管切开、开胸的正常犬被动呼气期间进行了阻断实验，同时用肺泡囊在三个部位测量肺泡压力。我们发现，在没有胸壁的情况下，ΔPinit仅反映气道阻力，而ΔPdif几乎完全可归因于肺组织的应力恢复特性。
