Amini R, Narusawa U
Department of Mechanical and Industrial Engineering, Northeastern University, Boston, MA 02115, USA.
J Biomech Eng. 2008 Jun;130(3):031020. doi: 10.1115/1.2913343.
A respiratory system model (RSM) is developed for the deflation process of a quasistatic pressure-volume (P-V) curve, following the model for the inflation process reported earlier. In the RSM of both the inflation and the deflation limb, a respiratory system consists of a large population of basic alveolar elements, each consisting of a piston-spring-cylinder subsystem. A normal distribution of the basic elements is derived from Boltzmann statistical model with the alveolar closing (opening) pressure as the distribution parameter for the deflation (inflation) process. An error minimization by the method of least squares applied to existing P-V loop data from two different data sources confirms that a simultaneous inflation-deflation analysis is required for an accurate determination of RSM parameters. Commonly used terms such as lower inflection point, upper inflection point, and compliance are examined based on the P-V equations, on the distribution function, as well as on the geometric and physical properties of the basic alveolar element.
在先前报道的充气过程模型的基础上，开发了一种用于准静态压力 - 容积（P - V）曲线放气过程的呼吸系统模型（RSM）。在充气和放气阶段的RSM中，呼吸系统由大量基本肺泡单元组成，每个单元由活塞 - 弹簧 - 气缸子系统构成。基本单元的正态分布源自玻尔兹曼统计模型，其中肺泡闭合（开放）压力作为放气（充气）过程的分布参数。通过最小二乘法对来自两个不同数据源的现有P - V环数据进行误差最小化处理，证实了为准确确定RSM参数需要进行同步的充气 - 放气分析。基于P - V方程、分布函数以及基本肺泡单元的几何和物理特性，对诸如下拐点、上拐点和顺应性等常用术语进行了研究。
