How to Turn It Down: The Evidence and Opinions Behind Adult Venoarterial Extracorporeal Membrane Oxygenation Weaning

Abstract

Adequate and durable recovery in patients supported with venoarterial (VA) extracorporeal membrane oxygenation (ECMO) can be challenging to predict. Extracorporeal membrane oxygenation weaning is the process by which the ECMO flows are decreased to assess if a patient is ready for decannulation. The optimal strategies for deciding who to wean and how to wean VA ECMO remain undefined. A retrospective literature review was performed to understand the evidence supporting current practices in ECMO weaning and in particular patient selection and methods. Most published work and expert opinions agree that once the underlying process has resolved, the minimum required physiologic parameters for weaning from ECMO include: hemodynamic stability and cardiac pulsatility, adequate lung function to support oxygenation and ventilation, and evidence of recovered end organ function. Echocardiography is universally used to assess cardiac function during the weaning process. Currently, there is no consensus regarding who is eligible to wean or how to wean ECMO in adults. We have reviewed the literature to summarize the evidence and expert opinions behind VA ECMO weaning, and give an example of the protocol used at our center. We believe this protocol optimizes patient selection for weaning and helps to predict successful decannulation.

ECMO as Bridge to Heart Transplantation

“…Bridging to a durable mechanical circulatory support or HTx is considered when patients could not be weaned from the ECMO support because of a missed recovery of the myocardial function. Several weaning protocols are described in the literature [12,13] and almost universally consist in the gradual reduction of the ECMO support, while hemodynamics and echocardiography parameters are monitored. If the cardiac function is deemed severely and irreversibly impaired, a rapid assessment of the patient clinical conditions should be performed before listing for HTx.…”

“…Other conditions that were reported to be risk factors for death are infection, high levels of lactate, and liver dysfunction [5,[6][7][8][9][10][11][12][13][14][15][16][17][18][19].…”

How to Do Weaning and Decannulation in Adult Cardiac

“…ECMO weaning can be considered if the patient's blood pressure and pulse pressure begin to increase even after applying the same ECMO flow and using the same inotropic medications. When the patient's blood pressure increases, the minimum mean arterial pressure is maintained at about 60 mmHg, and inotropes are gradually reduced or rarely used [2].…”

Feasibility of pump‐controlled retrograde trial off in weaning from veno‐arterial ECMO in adults: A single‐center case series

“…[2][3][4][5][6][7] Nevertheless, limitations of these strategies include variability in circuit setup between institutions, and the risk of thromboembolic events during clamping of the circuit. 8,9 More importantly, evaluation of left and right ventricular function under a residual ECMO flow may not completely uncover the intolerance to the full volume of venous return, 10 especially in borderline patients.…”