ECMO Veno-Arterial (VA) ECMO Management 2

Question 1

Which hemodynamic finding is most consistent with the 'North-South syndrome' (Harlequin syndrome) in peripheral VA ECMO?

Accepted Answer

Hypoxic upper body with well-oxygenated lower body

Answer

In Harlequin syndrome, retrograde ECMO flow oxygenates the lower body while the patient's own failing heart delivers desaturated blood to the upper body and coronary arteries.

Question 2

A patient on peripheral VA ECMO develops limb ischemia in the cannulated leg. What is the primary intervention?

Accepted Answer

Place a distal perfusion cannula in the superficial femoral artery

Answer

A distal perfusion cannula (DPC) inserted antegrade into the superficial femoral artery restores distal limb perfusion while maintaining ECMO support.

Question 3

What does a persistently elevated pulmonary artery pressure on VA ECMO most likely indicate?

Accepted Answer

LV distension due to insufficient venting

Answer

Elevated PA pressures on VA ECMO suggest the left ventricle is distending because it cannot eject against the increased afterload imposed by the circuit.

Question 4

Which parameter best reflects native cardiac recovery during VA ECMO weaning trials?

Accepted Answer

Pulse pressure amplitude on arterial waveform

Answer

Increasing pulse pressure amplitude on the arterial waveform indicates the native heart is generating stroke volume, a key sign of myocardial recovery.

Question 5

In VA ECMO, the 'mixing cloud' refers to:

Accepted Answer

The zone in the aorta where ECMO and native cardiac output blood mix

Answer

The mixing cloud is the aortic zone where retrograde oxygenated ECMO blood meets antegrade native cardiac output; its position determines differential oxygenation.

ECMO - Extracorporeal Membrane Oxygenation Practice Test

ECMO - Extracorporeal Membrane Oxygenation Practice Test

ECMO Veno-Arterial (VA) ECMO Management 2