Steady-State Model of Pressure-Flow Characteristics Modulated by Occluders in Cardiopulmonary Bypass Systems
Steady-State Model of Pressure-Flow Characteristics Modulated by Occluders in Cardiopulmonary Bypass Systems
复制标题
心肺旁路系统中封堵器调节压力-流量特性的稳态模型
DOI：
10.1109/access.2020.3043470
复制
发表时间：
2023
期刊：
影响因子：
3.9
通讯作者：
Tsuji Toshio
中科院分区：
文献类型：
--
作者：
Takahashi Hidenobu;Soh Zu;Tsuji Toshio
心脏搭桥术是一种复杂的手术，涉及在心脏手术期间使用外部系统维持心脏和肺功能。它容易出现重大人为错误，这主要是由通过调节流速来控制灌注平衡的不适当的封堵器操作引起的。因此，需要进行自动封堵器控制;然而，封堵器操作与流速之间的关系仍不清楚。本研究的目的是使用稳态模型来评估封堵器控制对体外循环系统流量和压力的影响。采用牛顿流体（甘油溶液）和非牛顿流体（红细胞混浊液）进行灌注实验，研究封堵器对压力-流量特性的调节作用。我们还对流体进行了可视化，以验证测量数据的有效性。基于这些实验数据，推导出指数型阻塞压力模型来表示阻塞器的开口率与流量之间的关系。然后通过将阻塞压力模型与线性压力-流量模型相结合来实现估计。结果表明，组合模型对静脉和动脉侧的灌注实验数据拟合良好（R2分别为0.946和0.985; p <0.01）。此外，留一法交叉验证和Bland-Altman分析证实，组合模型可以准确地预测流速，比例误差和偏倚误差最小。因此，所提出的模型可以作为进一步开发心肺操作系统的基础。
Cardiopulmonary bypass is a complex procedure that involves the maintenance of heart and lung functions using an external system during cardiac surgery. It is prone to significant human errors, which are mainly caused by inappropriate occluder operation that controls the perfusion balance by adjusting flow rates. Hence, there is a requirement for automatic occluder control; however, the relationship between occluder operation and flow rates remains unclear. The aim of this study is to use a steady-state model to evaluate the influence of occluder control on the flow and pressure of a cardiopulmonary bypass system. Perfusion experiments were performed using Newtonian (glycerin solution) and non-Newtonian (erythrocyte turbid solution) fluids to investigate the pressure-flow characteristics modulated by the occluder. We also visualized the fluid to verify the validity of the measurement data. Based on these experimental data, an exponential occlusion-pressure model is derived to express the relationships between the opening ratio of the occluder and flow rate. Estimation is then achieved by combining the occlusion-pressure model with the linear pressure-flow model. Results reveal that the combined model fitted the perfusion experiment data well for the venous and arterial line side (R2= 0.946 and 0.985, respectively; p <; 0.01 ). Further, leave-one-out cross-validation and Bland-Altman analysis confirmed that the combined model could predict flow rates accurately with minimal proportional and bias errors. Therefore, the proposed model can serve as a basis for the further development of cardiopulmonary manipulation systems.