Modeling flow effects on thrombotic deposition in a membrane oxygenator
Modeling flow effects on thrombotic deposition in a membrane oxygenator
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DOI：
10.1046/j.1525-1594.2000.06384.x
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发表时间：
2000-01-01
影响因子：
2.4
通讯作者：
Wagner, WR
中科院分区：
文献类型：
--
作者：
Gartner, MJ;Wilhelm, CR;Wagner, WR
研究了以下假设：根据计算流体力学 (CFD) 的预测，膜氧合器中的低血流速度区域与临床血栓沉积区域相对应。将二十个肝素涂层氧合器用于成人体外膜氧合后进行切片。在整个支持期间，通过肝素输注将活化凝血时间 (ACT) 维持在大约 180 秒。系统地拍摄了横截面，并制作了幻灯片以允许图像投影在数字化板上。追踪血栓沉积以允许创建装置横截面图像，该图像具有代表血栓沉积频率的重叠色标。开发了二维 CFD 模型来预测整个氧合器横截面的血流速度。在 CFD 模型血流速度和血栓沉积图之间进行了直接空间比较。在 CFD 模型中进行了理论氧合器设计修改，以研究可能最大限度地减少低血流速度区域的流动路径。 CFD 结果表明，低速度区域与血栓沉积高发区域定性匹配。血栓沉积也与较长的灌注时间相关。这种将临床数据和 CFD 相结合的技术提供了将血流特征与血栓沉积联系起来的潜力，并代表了一种潜在的强大的新方法，用于优化氧合器血流相关的生物相容性。
The hypothesis that regions of low blood velocity in a membrane oxygenator, as predicted by computational fluid dynamics (CFD), would correspond with regions of clinical thrombotic deposition was investigated. Twenty heparin-coated oxygenators were sectioned following use in adult extracorporeal membrane oxygenation. The activated clotting time (ACT) was maintained at approximately 180 s via heparin infusion throughout the support period. Cross-sections were systematically photographed, and slides made to allow image projection upon a digitizing pad. Thrombotic deposition was traced to allow creation of a device cross-section image with an overlaid color scale representing thrombotic deposition frequency. A two-dimensional CFD model was developed to predict blood velocities throughout the oxygenator cross-section. Direct spatial comparisons were made between maps of CFD modeled blood speed and thrombotic deposition. Theoretical oxygenator design modification was performed within the CFD model to investigate flow paths which might minimize regions of low blood velocity. CFD results demonstrated that low velocity regions qualitatively matched regions with a high incidence of thrombotic deposition. Thrombotic deposition was also correlated to longer perfusion periods. This technique of coupling clinical data and CFD offers the potential to relate flow characteristics to thrombotic deposition and represents a potentially powerful new methodology for the optimization of oxygenator flow-related biocompatibility.