ECMO Veno-Arterial (VA) ECMO Management 3

Question 1

During VA ECMO, which strategy is used to vent the left ventricle percutaneously without additional surgery?

Accepted Answer

Impella device placed across the aortic valve

Answer

An Impella device positioned across the aortic valve provides active LV unloading and venting, reducing distension during VA ECMO support.

Question 2

What is the primary reason VA ECMO increases myocardial oxygen demand compared to VV ECMO?

Accepted Answer

Increased LV afterload from retrograde aortic flow

Answer

Retrograde ECMO flow into the aorta increases LV afterload, forcing the recovering heart to work harder and increasing myocardial oxygen consumption.

Question 3

A VA ECMO circuit suddenly shows decreased flow with increasing inlet pressure. The most likely cause is:

Accepted Answer

Venous cannula malposition or hypovolemia

Answer

Decreased flow with high negative inlet (suction) pressure indicates inadequate venous drainage, most often from cannula malposition or hypovolemia causing suction events.

Question 4

In cardiogenic shock treated with VA ECMO, which laboratory value most directly reflects tissue oxygen delivery adequacy?

Accepted Answer

Serum lactate trend

Answer

Serial lactate trending is the most direct indicator of whether tissue oxygen delivery is adequate, with falling lactate confirming successful resuscitation.

Question 5

What is the recommended ECMO blood flow rate (as % of cardiac output) to achieve adequate systemic support in cardiogenic shock?

Accepted Answer

60–80%

Answer

VA ECMO typically targets 60–80% of the patient's estimated cardiac output (approximately 3–4 L/min) to provide adequate systemic perfusion.

ECMO - Extracorporeal Membrane Oxygenation Practice Test

ECMO - Extracorporeal Membrane Oxygenation Practice Test

ECMO Veno-Arterial (VA) ECMO Management 3