Hemodynamic evaluation and in vitro hemolysis evaluation of a novel centrifugal pump for extracorporeal membrane oxygenation

Abstract

Background: The STM CP-24 I centrifugal pump is a newly developed centrifugal pump for extracorporeal membrane oxygenation equipment. This study aimed to combine hydraulic experiments, hemodynamic numerical simulations, and standard in vitro hemolysis experiments to investigate the comprehensive performance of this centrifugal pump. Methods:In vitro experiments were first done to obtain the pressure-flow data of the centrifugal pump in its working range to evaluate its hydraulic performance. Next, the commonly used clinical working points were selected as boundary conditions, and a computational fluid dynamics method was applied to evaluate its hemodynamic performance. The blood pressure distribution, blood flow fields, and high-wall-shear-stress zones in the centrifugal pump were determined as indicators for hemodynamic evaluation. Finally, standard in vitro hemolysis experiments were performed to test the blood compatibility of this centrifugal pump (n=3 blood samples). In addition, its blood compatibility was evaluated in the form of the normalized index of hemolysis (NIH).Results: The pressure-flow curve of the centrifugal pump showed that the head pressure and flow of the centrifugal pump showed a mostly linear relationship within the whole working range. When the rotation speed of the centrifugal pump was 5,500 rpm, it achieved a hydraulic performance of 550 mmHg head pressure and 8 L/min output flow, which could meet the clinical needs of extracorporeal membrane oxygenation. Analysis of computational fluid dynamics data indicated that the centrifugal pump had excellent hemodynamic performance: even distribution of blood pressure in the pump, no blood flow stagnation zone or dead zone in the overall flow field, and secondary flows in the gap between the rotor and the volute that significantly reduced the volume of the low-blood-flow zone close to the impeller. There was no obvious high-shear-stress zone on the surface of the volute or the impeller, which will effectively reduce the risk of thrombosis. In vitro hemolysis experiments indicated that the centrifugal pump had excellent blood biocompatibility, with a NIH =0.0125±0.0022 g/100 L. Conclusions:The STM CP-24 I centrifugal pump has excellent hydraulic performance, a reasonable design of the hemodynamic structure of the blood pump, and excellent blood compatibility. Therefore, it can meet clinical needs.

Hemostatic alterations during extracorporeal membrane oxygenation in ovine veno‐venous and veno‐arterial models

“…10 sheep were randomly divided into the V‐A (veno‐arterial) group ( n = 5) that underwent V‐A ECMO and the V‐V (veno‐venous) group ( n = 5) that underwent V‐V ECMO. All were scheduled to be supported for 168 h. For the V‐V group, the circuits were composed of Hilite7000LT (XENIOS, Heilbronn, Germany) 11 and STM CP‐24 I centrifugal pump (Jiangsu STMed Technologies Co., Suzhou, China) 12 . The 23 Fr Avalon Elite (Maquet, Rastatt, Germany) double‐lumen cannula was inserted through the right external jugular vein.…”

“…All were scheduled to be supported for 168 h. For the V-V group, the circuits were composed of Hilite7000LT (XENIOS, Heilbronn, Germany) 11 and STM CP-24 I centrifugal pump (Jiangsu STMed Technologies Co., Suzhou, China). 12 The 23 Fr Avalon Elite (Maquet, Rastatt, Germany) double-lumen cannula was inserted through the right external jugular vein. For the V-A group, the circuits were composed of BE-PLS 2050 (Maquet, Rastatt, Germany) 11 and STM CP-24 I centrifugal pump.…”

Polymer-Drug Anti-Thrombogenic and Hemocompatible Coatings as Surface Modifications

“…The development of pulsatile pumps, first used in the 1950s, paved the way for continuous flow pumps that are now commonly used in heart transplants and as cardiac assist devices. The ongoing advancements in blood pump technology continue to improve patient outcomes and redefine the field of cardiology [ 89 ]. Research carried out in this area improves the construction of pumps, which leads to increasingly better results.…”

A numerical study of the hemodynamic behavior and gas transport in cardiovascular systems with severe cardiac or cardiopulmonary failure supported by venoarterial extracorporeal membrane oxygenation

“…These studies provided important insights for understanding the effects of ECMO from various perspectives spanning from systemic hemodynamics to microcirculation perfusion, nevertheless, most of them were restricted by available techniques for in vivo measurements, making the findings less comprehensive or lack quantitative details on some variables of interest (e.g., flow patterns near the cannulation sites, oxygen saturations in different end-organs). Such limitations of in vivo studies may be partly overcome by in vitro or ex-vivo studies, especially those based on mock loop models ( Ki et al, 2019 ; Fu et al, 2021 ; Caspari et al, 2022 ; Rozencwajg et al, 2022 ; Sayed et al, 2022 ). This sort of studies are however limited by the high cost of fabricating models mimicking the complex vascular structure and difficulties in representing various cardiovascular properties using artificial devices.…”