Department of Surgery, University of Maryland School of Medicine, Baltimore, MD, USA.
Fischell Department of Bioengineering, A. James Clark School of Engineering, University of Maryland, College Park, MD, USA.
Int J Artif Organs. 2021 Nov;44(11):829-837. doi: 10.1177/03913988211041635. Epub 2021 Sep 8.
Blood pumps have been increasingly used in mechanically assisted circulation for ventricular assistance and extracorporeal membrane oxygenation support or during cardiopulmonary bypass for cardiac surgery. However, there have always been common complications such as thrombosis, hemolysis, bleeding, and infection associated with current blood pumps in patients. The development of more biocompatible blood pumps still prevails during the past decades. As one of those newly developed pumps, the Breethe pump is a novel extracorporeal centrifugal blood pump with a hybrid magnetic and mechanical bearing with attempt to reduce device-induced blood trauma. To characterize the hydrodynamic and hemolytic performances of this novel pump and demonstrate its superior biocompatibility, we use a combined computational and experimental approach to compare the Breethe pump with the CentriMag and Rotaflow pumps in terms of flow features and hemolysis under an operating condition relevant to ECMO support (flow: 5 L/min, pressure head: ~350 mmHg). The computational results showed that the Breethe pump has a smaller area-averaged wall shear stress (WSS), a smaller volume with a scalar shear stress (SSS) level greater than 100 Pa and a lower device-generated hemolysis index compared to the CentriMag and Rotaflow pumps. The comparison of the calculated residence times among the three pumps indicated that the Breethe pump might have better washout. The experimental data from the in vitro hemolysis testing demonstrated that the Breethe pump has the lowest normalized hemolysis index (NIH) than the CentriMag and Rotaflow pumps. It can be concluded based on both the computational and experimental data that the Breethe pump is a viable pump for clinical use and it has better biocompatibility compared to the clinically accepted pumps.
血泵在机械辅助循环中越来越多地用于心室辅助和体外膜氧合支持，或在体外循环期间用于心脏手术。然而，当前的血泵在患者中总是存在常见的并发症，如血栓形成、溶血、出血和感染。在过去几十年中，开发更具生物相容性的血泵一直是当务之急。作为新开发的血泵之一，Breethe 泵是一种新型的体外离心血泵，具有混合磁和机械轴承，试图减少器械引起的血液创伤。为了描述这种新型泵的流体动力学和溶血性能，并证明其优越的生物相容性，我们使用计算和实验相结合的方法，根据与 ECMO 支持相关的操作条件（流量：5L/min，压力头：~350mmHg），比较了 Breethe 泵与 CentriMag 和 Rotaflow 泵在流量特性和溶血方面的差异。计算结果表明，与 CentriMag 和 Rotaflow 泵相比，Breethe 泵的壁面剪切应力（WSS）平均值更小，具有大于 100Pa 的标量剪切应力（SSS）水平的体积更小，器械产生的溶血指数更低。三种泵的停留时间比较表明，Breethe 泵的冲洗效果可能更好。体外溶血试验的实验数据表明，Breethe 泵的归一化溶血指数（NIH）低于 CentriMag 和 Rotaflow 泵。基于计算和实验数据，可以得出结论，与临床认可的泵相比，Breethe 泵是一种可行的临床应用泵，具有更好的生物相容性。
