NEW METHODOLOGIES FOR THE DESIGN OF SMALL BLOOD PUMPS

小型血泵设计的新方法

• 批准号: 7069038
• 负责人: GERSON ROSENBERG
• 金额: $ 64.39万
• 依托单位: PENNSYLVANIA STATE UNIV HERSHEY MED CTR
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-04-15 至 2008-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7069038
• 关键词: antithrombogenic surface; bioengineering /biomedical engineering; biomedical device power system; biomedical equipment development; cardiovascular disorder; circulatory assist; clinical biomedical equipment; computer simulation; cow; fluid flow; heart prosthesis; hemodynamics; hemolysis; implant; medical implant science; miniature biomedical equipment; shear stress; thrombosis; ultrasound blood flow measurement

DESCRIPTION (provided by applicant): The long-term objective of this research is to make pulsatile heart replacement systems available to smaller adult patients. This is a non-trivial matter, because reduction in the size of a pulsatile blood pump affects (1) the fluid dynamics of the pump, (2) the energetics of the pump and actuator, and (3) the stresses experienced by the blood contacting materials. Thus, we consider studies such as those described here to be critical to the availability of artificial hearts and pulsatile ventricular assist devices for the full spectrum of adult patients. We propose to study the underlying principles of pump size reduction through three specific aims: FIRST, we will compare in vitro measurements of the flow field with in vivo measures of thrombogenesis and hemolysis. Specifically, we will use Computational Fluid Dynamics to predict the flow field and Laser Doppler Anemometry and Particle Image Velocimetry to measure fluid velocity and shear rate with a high degree of spatial and temporal resolution, in pump chambers designed according to various scaling parameters. Classical dimensionless analysis will serve as guidance in scaling to achieve fluid dynamic similitude, and to generalize these measurements for predictive purposes. The significance of these findings will be assessed through in vivo studies in calves using completely implanted blood pumps, using the same pump chambers under similar fluid dynamic conditions. Thrombogenesis will be assessed through hematology studies and explant analysis. Platelet and fibrin adhesion will be quantified using post explant gross exam, histological examination and multi-scale surface analysis. Rapid manufacturing methods will be used to fabricate the variety of pumping chambers required for these experiments. SECONDLY, we will develop relationships governing energetic performance of the system, utilizing a computer simulation of the energy converter, blood pump, circulation, controller, and energy transmission system. We will thereby optimize the major subsystems to minimize power consumption. Results will be validated on a mock circulatory loop. THIRDLY, we will study the effects of reduced pump chamber size and pump shape parameters on biomaterial stresses using finite element analysis. Predicted strains will be validated using statically pressurized pump chambers. We expect that this research will be broadly applicable to pulsatile blood pump design, especially by improving our understanding of the relationships between fluid dynamics and thrombogenesis in a complex, time-varying flow field. This work requires a multi-disciplinary effort in surgery; engineering, fluid mechanics, and hematology, with the means to efficiency manufacture blood pump systems and carry out the necessary in vitro and in vivo studies.

描述（由申请人提供）： 这项研究的长期目的是使较小的成年患者可用的脉动心脏替代系统。这是一个非平凡的问题，因为脉冲血泵的大小减少会影响（1）泵的流体动力学，（2）泵和执行器的能量，以及（3）血接触材料所经历的压力。因此，我们认为此处描述的研究对成年患者的全部范围的人造心脏和脉冲心室辅助设备的可用性至关重要。我们建议通过三个特定目的研究较小泵尺寸的基本原理： 首先，我们将将流场的体外测量与体内的血栓形成和溶血测量进行比较。具体而言，我们将使用计算流体动力学来预测流场和激光多普勒动态测定法和粒子图像速度法，以在根据各种尺寸的参数设计的泵室中，以高度的空间和时间分辨率测量流体速度和剪切速率。经典的无量纲分析将作为扩展以实现流体动态相似的指导，并以预测目的概括这些测量值。这些发现的重要性将通过在相似的流体动态条件下使用相同的泵室在犊牛中的体内研究来评估。血栓形成将通过血液学研究和外植体分析评估。血小板和纤维蛋白的粘附将通过外植后总检查，组织学检查和多尺度表面分析来量化。快速制造方法将用于制造这些实验所需的各种抽水室。其次，我们将利用能源转换器，血泵，循环，控制器和能量传输系统的计算机模拟来建立有关系统能量性能的关系。因此，我们将优化主要子系统以最大程度地减少功耗。结果将在模拟循环循环中进行验证。 第三，我们将研究使用有限元分析的泵室大小和泵形参数对生物材料应力的影响。预测菌株将使用静态加压泵室验证。我们预计这项研究将广泛适用于脉动血泵设计，尤其是通过提高我们对复杂，时变流场中流体动力学与血栓形成之间关系的理解。这项工作需要在手术方面做出多学科的工作；工程，流体力学和血液学，具有生产血泵系统的手段，并进行了必要的体外和体内研究。