Clark Timothy W I, Van Canneyt Koen, Verdonck Pascal
Section of Interventional Radiology, Department of Radiology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA.
Semin Dial. 2012 Sep-Oct;25(5):574-81. doi: 10.1111/j.1525-139X.2012.01052.x. Epub 2012 Feb 22.
We examined flow characteristics and recirculation of a novel dialysis catheter with helically contoured lumens, which optimize the vectors of blood entering and leaving the device. Computational flow dynamics were used to measure shear stress, residence time (RT), Platelet Lysis Index (PLI), and recirculation of the study catheter, termed the VectorFlow catheter, compared with the Palindrome catheter. Bench and animal models were used to measure recirculation compared with other dialysis catheter designs. The VectorFlow catheter was associated with an 18% reduction in mean shear stress compared with the Palindrome catheter, at 13.6 and 16.6 Pa, respectively. Low PLI was seen with the VectorFlow (PLI = 0.019) and Palindrome (PLI = 0.015) catheters. The VectorFlow catheter was associated with a % RT >0.030 seconds of 1.2%, compared to 0.9% for the Palindrome. Calculated recirculation of the VectorFlow, Palindrome, and step-tip catheter designs in reversed position were 1.2 × 10(-4) %, 0.039%, and 13.6%, respectively. In vitro, the VectorFlow catheter had no detectable recirculation (0%) compared to 7.3-9.5% with the Palindrome at flow rates of 400-600 ml/minute. In vivo, the VectorFlow catheter had no detectable recirculation, compared to 6.7-12% for the Palindrome. The VectorFlow catheter was associated with an absence of detectable recirculation with favorable flow dynamics.
我们研究了一种具有螺旋形内腔的新型透析导管的血流特性和再循环情况，这种设计优化了血液进出该装置的矢量。采用计算流体动力学来测量研究导管（称为矢量流导管）与回文导管相比的剪切应力、停留时间（RT）、血小板裂解指数（PLI）和再循环情况。使用实验台和动物模型来测量与其他透析导管设计相比的再循环情况。与回文导管相比，矢量流导管的平均剪切应力分别降低了18%，分别为13.6和16.6帕。矢量流导管（PLI = 0.019）和回文导管（PLI = 0.015）的PLI较低。矢量流导管的停留时间>0.030秒的比例为1.2%，而回文导管为0.9%。计算得出，矢量流、回文和阶梯尖端导管设计在反向位置时的再循环率分别为1.2×10⁻⁴%、0.039%和13.6%。在体外，矢量流导管在400 - 600毫升/分钟的流速下未检测到再循环（0%），而回文导管为7.3 - 9.5%。在体内，矢量流导管未检测到再循环，而回文导管为6.7 - 12%。矢量流导管具有良好的血流动力学，且未检测到再循环。
