ECMO Foundations of ECMO and ECMO Management 5

Question 1

The pre-pump (inlet) pressure on an ECMO circuit is characteristically:

Accepted Answer

Negative, reflecting the suction generated by the drainage cannula

Answer

The inlet (drainage) limb operates at subatmospheric (negative) pressure as the pump generates suction to pull blood from the venous circulation.

Question 2

An ECMO patient develops sudden circuit thrombosis with loss of flow. The immediate priority is:

Accepted Answer

Clamp cannulas, initiate CPR if indicated, and prepare for emergency circuit change

Answer

Cannula clamping prevents air or emboli from entering the patient, CPR maintains perfusion if needed, and a circuit change is performed urgently to restore ECMO support.

Question 3

When weaning VV-ECMO, the clinician assesses readiness by:

Accepted Answer

Reducing sweep gas flow to zero and observing native gas exchange on the ventilator

Answer

A VV-ECMO weaning trial involves turning sweep gas to zero so the oxygenator is bypassed functionally, allowing assessment of whether the native lungs can sustain adequate gas exchange.

Question 4

A patient on VA-ECMO for cardiogenic shock shows improving echo function. The correct weaning strategy involves:

Accepted Answer

Gradually reducing ECMO flow while monitoring hemodynamic parameters and echo

Answer

VA-ECMO is weaned by stepwise flow reductions with concurrent hemodynamic and echocardiographic monitoring to confirm the heart can sustain adequate output.

Question 5

Which laboratory finding during ECMO warrants the most urgent evaluation for heparin-induced thrombocytopenia (HIT)?

Accepted Answer

Platelet count drop of greater than 50% on days 5–10 despite no circuit changes

Answer

A >50% platelet count drop on days 5–10 of heparin exposure is the classic temporal pattern raising strong suspicion for HIT, warranting a 4T score assessment and HIT antibody testing.

ECMO - Extracorporeal Membrane Oxygenation Practice Test

ECMO - Extracorporeal Membrane Oxygenation Practice Test

ECMO Foundations of ECMO and ECMO Management 5