Tani J, Nakamura M, Sasaki H, Okubo T, Takishima T, Hildebrandt J
Tohoku J Exp Med. 1982 Jun;137(2):125-36. doi: 10.1620/tjem.137.125.
The mechanical behavior of bronchial volume with respect to parenchymal properties, and to both the intrabronchial and pleural pressure, was investigated utilizing a theory of finite elasticity. Treating the lung parenchyma as a compressible continuum, we derived a simple strain-energy density function from pressure-volume curves of saline-filled lungs. On the basis of this function, large deformations of the fluid-filled excised dog lobe could be analyzed by numerical procedures. For the purpose of obtaining peribronchial stress, the lung was represented by a hollow thick-walled cylinder corresponding to an axial bronchus with surrounding parenchyma. In general, we found that the theoretical results corresponded well to previous experimental results, being able to predict quantitatively the stress and strain around the bronchus during collapse previously demonstrated by Nakamura et al. Peribronchial radial and circumferential stresses were shown to be concentrated at the bronchial wall, but dissipated rapidly within 1-2 bronchial radii away from the wall. We conclude that the magnitude of regional lung recoil around bronchi during collapse can be plausibly estimated by a theoretical analysis of total lung pressure-volume relationships.
利用有限弹性理论，研究了支气管容积相对于实质特性以及支气管内压力和胸膜压力的力学行为。将肺实质视为可压缩连续体，我们从充生理盐水肺的压力-容积曲线中推导了一个简单的应变能密度函数。基于该函数，通过数值程序可以分析充液离体犬肺叶的大变形。为了获得支气管周围应力，将肺表示为一个空心厚壁圆柱体，对应于带有周围实质的轴向支气管。总体而言，我们发现理论结果与先前的实验结果吻合良好，能够定量预测中村等人先前证明的支气管塌陷过程中支气管周围的应力和应变。支气管周围的径向和周向应力集中在支气管壁，但在距壁1-2个支气管半径范围内迅速消散。我们得出结论，通过对全肺压力-容积关系进行理论分析，可以合理估计塌陷过程中支气管周围局部肺回缩的大小。
