Kallok M J, Wilson T A, Rodarte J R, Lai-Fook S J, Chevalier P A, Harris L D
J Appl Physiol Respir Environ Exerc Physiol. 1979 Jul;47(1):182-91. doi: 10.1152/jappl.1979.47.1.182.
A linear elasticity solution for the gravitational deformation of excised lungs was obtained. The accuracy of our solution was examined by comparing predicted and measured displacements of markers glued to the surface of canine lower lobes. The equations describing the strains in a lobe were used to predict the distribution of regional volumes and the slope of phase III (S3) of a single-breath oxygen (SBO2) test. The analysis predicted a negative S3. However, S3 was found to be positive in the five lobes tested, suggesting that factors other than gravity were responsible for the observed pattern of ventilation. In SBO2 tests repeated with increasing delays at end inflation, S3 progressively decreased, became negative, and was eventually abolished. Our equations predicted the most negative observed S3 well. We conclude that continuum mechanics can be used to describe the gravitational deformation of lungs and the resulting effect on ventilation distribution.
获得了切除肺脏重力变形的线弹性解。通过比较粘贴在犬下叶表面的标记物的预测位移和测量位移，检验了我们解的准确性。描述肺叶应变的方程用于预测区域容积分布和单次呼吸氧气（SBO2）试验第三阶段（S3）的斜率。分析预测S3为负。然而，在所测试的五个肺叶中发现S3为正，这表明除重力外的其他因素导致了观察到的通气模式。在终末充气时延迟时间增加的重复SBO2试验中，S3逐渐降低，变为负，最终消失。我们的方程很好地预测了观察到的最负的S3。我们得出结论，连续介质力学可用于描述肺脏的重力变形及其对通气分布的影响。
