Coupling of lung tissue tethering force to fluid dynamics in the pulmonary circulation
Coupling of lung tissue tethering force to fluid dynamics in the pulmonary circulation
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DOI：
10.1002/cnm.1386
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发表时间：
2010-07-01
影响因子：
2.1
通讯作者：
Tawhai, M. H.
中科院分区：
文献类型：
--
作者：
Burrowes, K. S.;Tawhai, M. H.
已知呼吸期间肺容量的动态变化和姿势的改变都会影响肺内灌注的分布。在这里，我们耦合计算模型的肺血流和实质组织力学，以产生一种新的流动模型，预测组织变形，同时在不同的肺容量和姿势的流量分布。该模型被用来研究肺容量的影响，由于正常的变化，在轴向和径向拴系力的流量分布。有限变形弹性用于预测肺组织的体积变化和组织内的合成束缚压力。肺动脉网络的有限元模型嵌入肺体积内并随组织变形。稳态血流的空间分布预测使用Poiffille阻力（包括重力），质量守恒，和血管压力半径关系。计算相对于重力依赖高度的血流梯度。由于组织变形增加，预测仰卧（与俯卧相比）模型的倾斜度始终更陡。肺容量减少导致重力依赖性血流梯度增加，这主要是由于轴向血管拉伸对动脉血管长度和半径的影响。版权所有（C）2010约翰威利父子有限公司
Dynamic changes in lung volume during breathing and alteration of posture are both known to influence the distribution of perfusion within the lung. Here we couple computational models of pulmonary blood flow and parenchymal tissue mechanics to produce a novel flow model that predicts tissue deformation simultaneously with flow distributions at different lung volumes and postures. The model is used to study the effect of lung volume on flow distribution as a result of normal variation in axial and radial tethering forces. Finite deformation elasticity is used to predict volume changes of the lung tissue and resultant tethering pressures within the tissue. A finite element model of the pulmonary arterial network is embedded within the lung volume and deforms with the tissue. The spatial distribution of steady-state blood flow is predicted using the Poiseuille resistance (including gravity), conservation of mass, and a vascular pressure radius relationship. Blood flow gradients with respect to gravitationally dependent height are calculated. Gradients are predicted to be consistently steeper in the supine (compared with prone) model due to increased tissue deformation. Decreased lung volume resulted in increased gravitationally dependent flow gradients, predominantly due to the effect of axial vessel stretch on the length and the radius of the arterial vessels. Copyright (C) 2010 John Wiley & Sons, Ltd.