NEW METHODOLOGIES FOR THE DESIGN OF SMALL BLOOD PUMPS

描述（由申请人提供）：本研究的目的是使脉动心脏置换系统可用于较小的成年患者。这是一个重要的问题，因为脉动血泵尺寸的减小影响（1）泵的流体动力学，（2）泵和致动器的能量学，以及（3）血液接触材料所经受的应力。因此，我们认为这些研究是至关重要的人工心脏和脉动心室辅助装置的可用性，为全方位的患者。我们建议通过三个具体目标来研究泵尺寸减小的基本原理：第一，利用CFD建模、实验流体动力学技术、体外测试和体内研究的综合方法，利用物理设计约束来显著改进尺寸减小的血泵和能量转换器设计。这些建模和体外研究将用于预测系统性能。将通过小牛体内研究评估这些结果的意义。将通过血液学研究、血小板活化研究和取出物分析评估血栓形成。将通过取出后大体检查、组织学检查和多尺度表面分析定量血小板和纤维蛋白粘附。第二，我们已经开发了控制系统的能量性能的关系，利用能量转换器、血泵、循环、控制器和能量传输系统的计算机模拟。我们将定制控制致动器的运动，以改善流体力学。还将在体外和体内评价这些研究的结果。第三，我们将改进和利用预测和最小化生物材料应力所需的改进FEA模型，以便缩小尺寸器械的耐用性不会受到泵缩放的不利影响。我们希望这项研究将广泛适用于脉动血泵的设计，特别是通过提高我们的理解之间的关系的表面效应，流体动力学，血栓形成在一个复杂的，随时间变化的流场。这项工作需要在外科、工程、流体力学和血液学方面进行多学科的努力，以有效地制造血泵系统并进行必要的体外和体内研究。 公共卫生相关性：本研究结合计算流体动力学、实验流体动力学、系统建模、有限元分析、体外和体内技术，开发了一种用于小型血泵设计的综合方法。

DESCRIPTION (provided by applicant): The 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 patients. We propose to study the underlying principles of pump size reduction through three specific aims: FIRST, Utilize an integrated method of CFD modeling, experimental fluid dynamics techniques, in vitro testing and in vivo studies to significantly improve reduced size blood pumps and energy converter designs utilizing physical design constraints. These modeling and in-vitro studies will be used to predict system performance. The significance of these findings will be assessed through in vivo studies in calves. Thrombogenesis will be assessed through hematology studies, platelet activation studies, and explant analysis. Platelet and fibrin adhesion will be quantified by post explant gross exam, histological examination and multi-scale surface analysis. SECONDLY, we have developed 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 tailor control of actuator movement to improve fluid mechanics. The results of these studies will also be evaluated in-vitro and in-vivo. THIRDLY, we will refine and utilize improved FEA models necessary for predicting and minimizing stresses in biomaterials, so that durability of reduced-size devices is not adversely affected by pump scaling. We expect that this research will be broadly applicable to pulsatile blood pump design, especially by improving our understanding of the relationships between surface effects, 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 efficiently manufacture blood pump systems and carry out the necessary in vitro and in vivo studies. PUBLIC HEALTH RELEVANCE: This research combines computational fluid dynamics, experimental fluid dynamics, systems modeling, finite element analysis, in vitro and in vivo techniques to develop a comprehensive method for the design of small blood pumps.