that是指chest wall tissue resistance吗？

Tissue Resistance

In 1955 a component of the work of breathing was attributed to the resistance caused by tissue deformation, and some years later this was measured in anaesthetized and paralysed subjects and termed the viscoelastic or ‘tissue’ component of respiratory resistance. Figure 3.4 shows the ‘spring and dashpot’ model, first described by D’Angelo et al,1 to illustrate tissue resistance. Dashpots here represent resistance and springs elastance (reciprocal of compliance).Upward movement of the upper bar represents an increase in lung volume, caused by contraction of the inspiratory muscles or the application of inflation pressure as shown in the diagram. There is good evidence that, in humans, the left-hand dashpot represents predominantly airway resistance. The spring in the middle represents the static elastance of the respiratory system. On the right there is a spring and dashpot arranged in series. With a rapid change in lung volume, the spring is extended, while the piston more slowly rises in the dashpot. In due course (2–3 seconds) the spring returns to its original length and so ceases to exert any influence on pressure/volume relationships.This spring therefore represents the time-dependent element of elastance. While it is still under tension at endinspiration, the combined effect of the two springs results in a high elastance, of which the reciprocal is the dynamic compliance. If inflation is held for a few seconds and movement of the piston through the right-hand dashpot is completed, the right-hand spring ceases to exert any tension, and the total elastance is reduced to that caused by the spring in the middle. The reciprocal of this elastance is the static compliance, which is therefore greater than the dynamic compliance. The system shown in Figure 3.4 is only a simplified scheme to which many further components could be added; nevertheless the model accords well with experimental findings.

（二）组织阻力

1955年，人们发现一部分呼吸功被用于克服组织变形所致的阻力，并于几年后在麻醉和肌松患者上测得该阻力，称之为呼吸阻力的黏弹性或“组织”成分。图3.4显示了D'Angelo等首先提出的组织阻力的“弹簧和阻尼器”模型。在这里，阻尼代表黏性阻力而弹簧代表弹性阻力（顺应性的倒数）。如图所示，上横杆向上移动表示吸气肌收缩或施加膨胀压力引起肺容积增加。左侧阻尼器显示了黏弹性组织的黏性阻力主要是气道阻力，中间的弹簧代表呼吸系统的静态弹性阻力。右侧是弹簧和阻尼器串联。随着肺容积的快速变化，弹簧被拉长，同时阻尼器中的活塞缓缓上升。在适当的时候（2~3秒），弹簧恢复到原始长度，因此不再对压力/容量关系有任何影响。因此这个弹簧代表了时间依赖性的弹性阻力。而吸气末弹簧仍然处于紧张状态，两个弹簧共同作用导致了高弹性阻力，其倒数即为动态顺应性。如果肺充气暂停数秒，右侧阻尼器的活塞运动完毕，右侧弹簧就不再施加任何张力，总弹性阻力就下降，等于中间弹簧所产生的弹性阻力。此时弹性阻力的倒数即为静态顺应性，因此静态顺应性大于动态顺应性。图3.4所示只是一个简化的展示，还可以添加更多的组件，然而该模型仍与实验结果很相符。

Fig. 3.4 ​The spring and dashpot model of D’Angelo et al1 Inflation of the lungs is represented by the bar moving upwards. The springs represent elastance (reciprocal of compliance), and the dashpots represent resistance. The spring and dashpot in series on the right confers time dependence, which is because of viscoelastic tissue resistance.

图3.4 D'Angelo等的弹簧和阻尼器模型^[1]。横杆上移表示肺充气。弹簧表示弹性阻力（顺应性的倒数），阻尼器表示黏性阻力。因为是黏弹性组织的阻力，右侧串联的弹簧和阻尼器的变化具有时间依赖性。

The time-dependent change in compliance represented by the spring and dashpot in series could be as a result of many factors. Redistribution of gas makes only a negligible contribution in a healthy human; the major component is because of viscoelastic flow resistance in tissue. In anaesthetized healthy subjects, tissue resistance is of the order of half of the respiratory system resistance, and seems to be largely unaffected by end-expiratory pressure or tidal volume.1Tissue resistance originates from both lung and chest wall tissues, with a significant proportion originating in the chest wall.1The magnitude and importance of this component, particularly in lung disease, is often underestimated, and it is clearly important to distinguish airway resistance from that afforded by the total respiratory system. Separate measurement of tissue resistance is described in the following section.

弹簧-阻尼器串联模型表示顺应性随时间变化是多因素导致的。气体重分布对健康人顺应性的时间依赖性影响微乎其微，主要原因是组织内的黏弹性气流阻力的影响。在麻醉的健康受试者中，组织阻力约为呼吸系统阻力的一半，其很大程度上不受呼气末压力或潮气量的影响^[1]。组织阻力来源于肺和胸壁组织，有相当比例来自胸壁^[1,2]。常常低估胸壁组织组织阻力的大小与重要性，尤其在有肺部疾病时，因此区分气道阻力和整个呼吸系统中的胸壁组织阻力很重要。组织阻力的单独测量将在下一节阐述。

that是指chest wall tissue resistance吗？谢谢