Cardio-Respiratory Engineering and Technology Laboratory, Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia.
Department of Mechanical and Aerospace Engineering, Monash University, Melbourne, Victoria, Australia.
Artif Organs. 2022 Jun;46(6):1068-1076. doi: 10.1111/aor.14179. Epub 2022 Feb 3.
Venoarterial extracorporeal membrane oxygenation (ECMO) provides mechanical support for critically ill patients with cardiogenic shock. Typically, the size of the arterial return cannula is chosen to maximize flow. However, smaller arterial cannulae may reduce cannula-related complications and be easier to insert. This in vitro study quantified the hemodynamic effect of different arterial return cannula sizes in a simulated acute heart failure patient.
Baseline support levels were simulated with a 17 Fr arterial cannula in an ECMO circuit attached to a cardiovascular simulator with targeted partial (2.0 L/min ECMO flow, 60-65 mm Hg mean aortic pressure-MAP) and targeted full ECMO support (3.5 L/min ECMO flow and 70-75 mm Hg MAP). Return cannula size was varied (13-21 Fr), and hemodynamics were recorded while keeping ECMO pump speed constant and adjusting pump speed to restore desired support levels.
Minimal differences in hemodynamics were found between cannula sizes in partial support mode. A maximum pump speed change of +600 rpm was required to reach the support target, and arterial cannula inlet pressure varied from 79 (21 Fr) to 224 mm Hg (13 Fr). The 15 Fr arterial cannula could provide the target full ECMO support at the targeted hemodynamics; however, the 13 Fr cannula could not due to the high resistance associated with the small diameter.
A 15 Fr arterial return cannula provided targeted partial and full ECMO support to a simulated acute heart failure patient. Balancing reduced cannula size and ECMO support level may improve patient outcomes by reducing cannula-related adverse events.
体外膜肺氧合（ECMO）为心源性休克的重症患者提供机械支持。通常，选择动脉回流插管的尺寸以最大化流量。然而，较小的动脉插管可能会减少与插管相关的并发症，并且更容易插入。这项体外研究量化了模拟急性心力衰竭患者中不同动脉回流插管尺寸的血液动力学效应。
在连接到心血管模拟器的 ECMO 回路中使用 17Fr 动脉插管模拟基线支持水平，目标为部分（2.0 L/min ECMO 流量，60-65mmHg 平均主动脉压-MAP）和目标完全 ECMO 支持（3.5 L/min ECMO 流量和 70-75mmHg MAP）。改变回流插管的尺寸（13-21Fr），同时保持 ECMO 泵速恒定，并调整泵速以恢复所需的支持水平，记录血液动力学。
在部分支持模式下，插管尺寸之间的血液动力学差异最小。需要最大泵速变化+600rpm 才能达到支持目标，并且动脉插管入口压力从 79mmHg（21Fr）变化到 224mmHg（13Fr）。15Fr 动脉插管可以在目标血液动力学下提供目标完全 ECMO 支持；然而，13Fr 插管由于与小直径相关的高阻力而无法提供。
15Fr 动脉回流插管为模拟急性心力衰竭患者提供了目标部分和完全 ECMO 支持。平衡减少插管尺寸和 ECMO 支持水平可以通过减少与插管相关的不良事件来改善患者的结局。
