Elasticity of Microvessels in Postmortem Human Lungs

Abstract

Recently we have demonstrated that in the case of cat, after the necessary morphometric and rheological data are collected, we can predict the pulmonary blood flow as a function of a number of physiological parameters with excellent accuracy. We can use the computing program to assess in vivo parameters such as the pulmonary surface (Engelberg et al., 1959; Yen and Foppiano, 1981; Yen et al., 1980; Zhuang et al., 1985). We believe that by analogy we can do the same for the human. Such a valid biophysical mathematical analysis of the pulmonary circulation of humans may have considerable value in further understanding the normal pulmonary circulation. An attempt is made to obtain a complete set of morphological and rheological data on the human lung from postmortem material obtained within 24 hours of death, in order to initiate and establish a theoretical model and computing program of pulmonary circulation. The model will be validated as far as possible from experimental data derived from flow experiments on isolated postmortem human lungs. It will correlate many physiological variables through a rational theory: the pressure in pulmonary artery, left atrium, airway, and pleura; the branching pattern of the vascular tree, including the branch number ratio, the diameter ratio, and the length ratio of all orders of vessels; the alveolar surface area; the capillary blood vessel characteristics; the rheological properties, including the distensibilities of all generations of blood vessels; and the flow properties of blood.