不同角度倾斜对人体心血管系统影响的仿真研究  

Simulation Study on Cardiovascular Effect Induced with Tilting at Different Angles.

作　　者：刘洋[1] 焦纯[1] 张国鹏[1] 张立藩[2] 卢虹冰[1] 

机构地区：[1]第四军医大学计算机应用教研室,陕西西安710032 [2]第四军医大学航空航天生理教研室,陕西西安710032

出　　处：《航天医学与医学工程》2009年第2期89-93,共5页Space Medicine & Medical Engineering

基　　金：国家自然科学基金(30470490);军队医药卫生科研基金(06MA225)

摘　　要：目的仿真研究不同角度倾斜对人体心血管系统血液动力学的影响,并与已发表实验数据比较,以校验所用分布式心血管系统数学模型是否可用于失重对心血管影响的仿真研究,提出存在问题及改进方向。方法利用该模型沿血管方向调整重力分量模拟人体倾斜角度的变化,计算变化过程中人体的心血管响应。结果随倾斜角度绝对值的增加,所有血管的平均血压都近似呈不同方向的指数变化。人体由直立体位转至水平体位,中心静脉压呈指数增加;心率虽呈指数降低,但变化幅度很小;每搏量呈线性增加。静脉系统的流体静压参考点位于右心房和下腔静脉之间。仿真结果与报道的人体倾斜或卧床实验数据相近。结论该模型可以有效地模拟人体倾斜角度变化时心血管系统的急性响应;但为了仿真长期航天失重环境下心血管系统的适应性变化,还需将血量调节,心脏与血管功能和结构的慢性适应变化,以及神经-体液调节等机制耦合进来。Objective To study the influence of hemodynamic effects on cardiovascular system under different tilt angles, compare simulation results with reported experimental data, and investigate the feasibility of proposed distributed cardiovascular model for simulation study in microgravity. Methods Simulated model was estabished according to the effect of postural changes along vessel segments. The response of cardiovascular system was computed iteratively during this process. Results With the absolute value of tilt angle increased, the mean pressure of all vessels changed exponentially. With the tilt angle changed from vertical to horizontal position, the central venous pressure increased exponentially, the heart rate decreases exponentially less, and the stroke volume increased linearly. The pressure distribution of vascular system indicated that the hydrostatic indifferent point of venous system located between the right atrium and inferior vena cava. The simulation results compared well with reported experimental data. Conclusion The model used can simulate the acute response of cardiovascular system to postural changes effectively. To simulate hemodynamic adaptation of cardiovascular system to microgravity, more anthropopathic vessel system, as well as more control mechanism including the regulation of blood volume, chronic adaptation of heart and vessels, and neurohumoral regulation, should he included.

关 键 词：失重模拟 心血管系统 倾斜 仿真 建模 中心静脉压 每搏量 心率 

分 类 号：R852.22[医药卫生—航空、航天与航海医学]