嵌合式端侧吻合方法在内瘘中的数值模拟分析

Numerical simulation analysis of engaging end-to-side anastomosis for internal fistula

目的通过数值模拟分析比较嵌合式和传统式两种端侧吻合方法在内瘘中的血流动力学影响。方法建立两种端侧吻合方法的内瘘模型,赋予适当的边界条件,分别生成两种模型的流体速度、压力、涡量云图以及流线图;沿吻合口管腔中心线计算压力、速度及涡量的数值,并相应显示在XY曲线图中。结果两个模型的计算流体力学分析结果显示:嵌合式吻合口在云图中的压力和速度的变化梯度均小于传统式吻合口,涡量的面积也小于后者;流线图中嵌合式吻合口附近的流线也更平整,紊乱的更少。在XY曲线图中清晰地显示了嵌合式吻合口的压力和速度变化梯度以及涡量强度均优于传统式吻合口。结论嵌合式吻合口的几何形态对血流动力影响更小,有助于保持内瘘的通畅。使用嵌合式端侧吻合是一项更符合几何造型的内瘘手术吻合方法。

Objective To compare the hemodynamic effects of two engaging and traditional end-to-side anastomoses by numerical simulating analysis for internal fistula.Methods Two fistula models of end-to-side anastomosis were developed and appropriate boundary conditions,cloud diagram of fluid velocity,pressure,vorticity and streamline diagram formed respectively.Along the center line of anastomotic lumen,the values of pressure,velocity and vorticity were calculated and displayed in an XY graph correspondingly.Results The results of two models with computational fluid dynamics showed that the pressure and velocity gradient of engaging anastomosis were smaller than traditional anastomosis in cloud diagram and the area of vorticity was less than the latter.In streamline diagram,streamline near engaging anastomosis was smoother and less disordered.And XY graph distinctly indicated that pressure and velocity gradient and vorticity intensity of engaging anastomosis were better than those of traditional anastomosis.Conclusion The geometric conformation of engaging anastomosis influences hemodynamics less and contributes more to maintain the patency of internal fistula.Thus the application of engaging end-to-side anastomosis is a kind of approach fitter for geometric design for internal fistula.