A micromechanical model of airway-parenchymal interdependence
A micromechanical model of airway-parenchymal interdependence
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DOI：
10.1114/1.270
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发表时间：
2000-03-01
影响因子：
3.8
通讯作者：
Bates, JHT
中科院分区：
文献类型：
--
作者：
Adler, A;Bates, JHT
肺实质相互依赖性的力量是气道平滑肌缩短的有效抑制剂，支气管反应性对肺容量的显着依赖性证明了这一点。在这项研究中，我们开发了一个数学计算机模型，用于研究实质相互依赖性对气道平滑肌缩短的影响。立方形肺泡壁的三维网络在其边界处被束缚，并包围着单个气道，其机械特性与肺泡实质相同。墙壁被赋予了高度非线性特性，因此模型的压力-体积行为与在狗身上测量的结果相匹配。通过增加气道壁的周向张力来实现气道收缩，然后求解模型的力平衡方程以计算气道壁和所有互连肺泡壁的平衡配置。将模型在不同跨肺压(P-tp)下预测的气道阻力的变化与在不同P-tp下诱导支气管收缩期间通过肺泡囊振荡器技术在狗身上获得的气道阻力变化进行比较(Balassy等人，J. Appl. Physiol. 78:875-880, 1995)。该模型在 P-tp 值高于约 0.5 kPa 时与数据相当匹配，但在较低 P-tp 时反应过于灵敏。通过包含额外的刚度项，我们能够使模型与所有 P-tp 处的数据相匹配，例如可能由气道壁本身产生的刚度项。 (C) 2000 年生物医学工程学会。 [S0090-6964(00)00203-4]。
The forces of parenchymal interdependence in the lung are potent inhibitors of airway smooth muscle shortening, as evidenced by the marked dependence of bronchial responsiveness on lung volume. Ln this study we developed a mathematical-computer model of the effects of parenchymal interdependence on airway smooth muscle shortening. A three-dimensional network of cuboidal alveolar walls was tethered at its boundaries and surrounded a single airway with mechanical properties identical to the alveolar parenchyma. The walls were assigned highly nonlinear properties so that the pressure-volume behavior of the model matched that measured in dogs. Constriction of the airway was achieved by increasing the circumferential tension in the airway wall, and then solving the force-balance equations of the model to calculate the equilibrium configurations of the airway wall and all the interconnecting alveolar walls. The changes in airway resistance predicted by the model at various transpulmonary pressures (P-tp) were compared to those obtained by the alveolar capsule oscillator technique in dogs during induced bronchoconstriction at various P-tp (Balassy et at, J. Appl. Physiol. 78:875-880, 1995). The model matched the data reasonably well at P-tp values above about 0.5 kPa, but was too responsive at lower P-tp. We were able to make the model match the data at all P-tp by including an additional stiffness term, such as might conceivably arise from the airway wall itself. (C) 2000 Biomedical Engineering Society. [S0090-6964(00)00203-4].