Point-of-Care Ultrasound for Peripheral Veno-Arterial Extracorporeal Membrane Oxygenation Without Left Ventricular Venting

Summary

This protocol outlines the use of point-of-care ultrasound (POCUS) to monitor patients on peripheral veno-arterial extracorporeal membrane oxygenation (V-A ECMO) without left ventricular venting. It evaluates left ventricular distension, intracardiac or aortic root thrombus, and identifies useful cardiac POCUS parameters for weaning from V-A ECMO.

Abstract

Over the past several decades, veno-arterial extracorporeal membrane oxygenation (V-A ECMO) has become a critical tool in the management of patients with severe cardiogenic shock and cardiopulmonary failure. Due to the inherent instability of these patients, their transport away from intensive care units is fraught with risk. As a result, bedside diagnostic tools are essential for their daily care. One such tool is point-of-care ultrasound (POCUS) of the heart, which can non-invasively assess several parameters: left ventricular (LV) performance (size, systolic function, stroke volume, aortic valve opening), right ventricular (RV) performance (size, systolic function), and the presence of intracardiac thrombus. Additionally, POCUS can assist in evaluating readiness for V-A ECMO weaning and eventual decannulation. Despite its potential, the use of POCUS in the context of V-A ECMO remains inconsistent due to variability in provider training. This study aims to address this gap by detailing POCUS image acquisition in V-A ECMO, particularly in the absence of LV venting. It covers key aspects such as patient positioning, transducer selection, probe placement, acquisition sequence, and image optimization.

Introduction

Extracorporeal membrane oxygenation (ECMO) is a potentially life-saving temporizing strategy for patients, which has seen an ever-increasing utilization rate^1,2. ECMO has two different configurations: veno-venous (V-V) and veno-arterial (V-A). Over the past several decades, V-A ECMO has emerged as a fundamental tool in the care of patients with severe cardiogenic shock and cardiopulmonary failure^3,4,5,6. The two cannulation strategies for V-A ECMO are central and peripheral

Protocol

All procedures performed in studies involving human participants were in accordance with the ethical standards of the Vanderbilt University Medical Center institutional research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. The protocol was derived after a review of the published literature by an expert panel of intensivists^16,21,22,23

Discussion

Significance with respect to existing methods
The utilization of V-A ECMO as a rescue therapy for acute decompensated cardiac failure has been on the rise¹. Peripheral V-A ECMO is utilized as a temporary intervention to allow time for the acutely failing heart to recover while optimizing end-organ function^2,3. Although there is a lack of established guidelines regarding the application of echocardiography in the cont.......

Materials

Name	Company	Catalog Number	Comments
Affiniti	Philips	Affiniti 70
Edge 1 ultrasound machine	SonoSite	Edge II
Vivid iq	GE