动脉压对静脉血管壁周向应力分布的影响  

Influence of Arterial Pressure on Distribution of Circumferential Stresses in Vein Wall

作　　者：孙辉[1] 龚克勤[1] 覃开蓉[1] 柳兆荣[1] 纪广玉[2] 邹良建[2] 张宝仁[2] 

机构地区：[1]复旦大学生物力学实验室,上海200433 [2]第二军医大学长海医院胸外科,上海200433

出　　处：《力学季刊》2003年第4期473-481,共9页Chinese Quarterly of Mechanics

基　　金：国家自然科学基金重点项目(10132020);复旦大学学生科技创新行动支持计划(B2707)

摘　　要：自体静脉是病变动脉管段常用的替代物。移植后因承受压力急剧升高引起的静脉管壁应力改变是影响移植手术的主要因素之一。为了比较移植前(静脉压作用下)和移植后(动脉压作用下)静脉管壁的周向应力分布,本文通过检测一定轴向伸长比条件下静脉管的p(压力)——V(容积)试验数据,利用3参数的应变能密度函数对实验数据进行拟合,进而求得静脉管壁的残余应力和沿血管壁的周向应力分布。对狗的股静脉和颈静脉的分析结果表明,在动脉压作用下静脉管壁周向应力将急剧增大。与处于静脉压环境相比,处于动脉压环境中的颈静脉管周向应力将增大差不多2个数量级。计算结果还显示,静脉管壁残余应力的数值虽然比动脉管壁的相应值小很多,但是与动脉管相同,血管壁残余应力依然对静脉管壁上的周向应力分布影响显著,残余应力的存在将大大削弱在静脉管内壁处的周向应力集中,使周向应力沿静脉管壁厚的变化梯度明显减小。Autologous vein is often used as the substitute of disabled artery segment. The change of stress in the wall of grafted vein, which is resulted from the rapid increase of pressure in the lumen, is one of the important factors that influence the vein graft. In order to compare the distribution of circumferential stresses before graft (under the vein pressure) and immediately after graft (under the arterial pressure), the p(pressure)- V(volume) data of vein at certain axial extension ratio was measured and fitted using the 3-parameter strain energy density function. The residual stress and the circumferential stress in the vein wall could be obtained. The analysis on canine femoral and jugular veins shows that when those vessels are placed under arterial pressure, the circumferential stress in their wall will increase rapidly. For example, under the arterial pressure, in the wall of jugular vein, the circumferential stress will increase nearly 2 order comparing with its counterpart under the vein pressure. Furthermore, the results indicate that, like the residual stress in the artery wall, the residual stress in the vein wall can greatly weaken the circumferential stress concentration at the inner wall and result in an obviously smaller circumferential stress gradient along the radial direction, although the value of the residual stress in vein wall is much smaller than that in artery wall.

关 键 词：静脉移植 压力-容积关系 零应力状态 残余应力 周向应力 

分 类 号：O351.2[理学—流体力学]