Patient-specific modelling of head-up tilt.
Patient-specific modelling of head-up tilt.
复制标题
患者特定的抬头倾斜建模。
DOI：
10.1093/imammb/dqt004
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
Olufsen,MetteS
中科院分区：
文献类型：
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作者：
Williams,NakeyaD;Wind-Willassen,Øistein;Wright,AndrewA;REUProgram;Mehlsen,Jesper;Ottesen,JohnnyT;Olufsen,MetteS
平视倾斜（HUT）的短期心血管反应涉及复杂的心血管调节，以维持血压在稳态水平。本文提出了一个患者特定的模型，该模型使用心率作为输入来拟合HUT期间动脉血压数据的动态变化。该模型包含五个室室，分别代表体循环上下体的动脉和静脉，以及促进心脏泵送的左心室。一个基于生理学的子模型描述了HUT期间血液向下肢的重力池，一个心血管调节模型调节心脏收缩力和血管阻力对血压变化的影响。名义参数值是根据患者特定数据和文献估计计算的。该模型通过使用参数估计技术来呈现患者特异性。这个过程包括敏感性分析、可识别参数子集的预测和非线性优化。本文提出的方法被应用于分析5名健康年轻受试者的主动脉和颈动脉HUT数据。结果表明，有可能确定一个可以估计的模型参数子集，允许模型拟合在颈动脉分叉水平观察到的动脉血压变化。此外，该模型估计了没有数据的动脉和静脉血压、血容量和心输出量的生理合理值。
Short-term cardiovascular responses to head-up tilt (HUT) involve complex cardiovascular regulation in order to maintain blood pressure at homoeostatic levels. This manuscript presents a patient-specific model that uses heart rate as an input to fit the dynamic changes in arterial blood pressure data during HUT. The model contains five compartments representing arteries and veins in the upper and lower body of the systemic circulation, as well as the left ventricle facilitating pumping of the heart. A physiologically based submodel describes gravitational pooling of the blood into the lower extremities during HUT, and a cardiovascular regulation model adjusts cardiac contractility and vascular resistance to the blood pressure changes. Nominal parameter values are computed from patient-specific data and literature estimates. The model is rendered patient specific via the use of parameter estimation techniques. This process involves sensitivity analysis, prediction of a subset of identifiable parameters, and non-linear optimization. The approach proposed here was applied to the analysis of aortic and carotid HUT data from five healthy young subjects. Results showed that it is possible to identify a subset of model parameters that can be estimated allowing the model to fit changes in arterial blood pressure observed at the level of the carotid bifurcation. Moreover, the model estimates physiologically reasonable values for arterial and venous blood pressures, blood volumes and cardiac output for which data are not available.