ECMO Weaning and Decannulation 2

Question 1

During VV-ECMO weaning, which parameter most reliably indicates adequate native lung recovery before a trial off?

Accepted Answer

SpO2 > 95% on FiO2 ≤ 0.4 with sweep gas off

Answer

SpO2 >95% with acceptable PaCO2 on room-air sweep-off conditions demonstrates that native lungs can sustain gas exchange independently.

Question 2

A patient on VA-ECMO for cardiogenic shock undergoes a 30-minute clamp trial. During the trial, the arterial pressure waveform becomes pulsatile with a pulse pressure of 40 mmHg. This finding indicates:

Accepted Answer

Adequate left ventricular recovery to consider decannulation

Answer

A robust pulsatile waveform during VA-ECMO clamping reflects meaningful left ventricular stroke volume, suggesting cardiac recovery.

Question 3

Which echocardiographic finding during a VA-ECMO weaning trial would most strongly support proceeding to decannulation?

Accepted Answer

LVEF ≥ 35% with no severe valvular abnormality

Answer

LVEF ≥ 35% without severe valvular disease suggests sufficient cardiac reserve to sustain circulation without ECMO support.

Question 4

When weaning VV-ECMO, the sweep gas flow is progressively reduced. What physiologic effect does reducing sweep gas primarily alter?

Accepted Answer

Carbon dioxide removal by the oxygenator

Answer

Sweep gas flow controls the rate of CO2 removal across the membrane; reducing it raises PaCO2 and stimulates native respiratory drive.

Question 5

After surgical decannulation of a femoral venous cannula, the preferred method for achieving hemostasis at the venous access site in a fully anticoagulated patient is:

Accepted Answer

Manual pressure for 30–45 minutes followed by a pressure dressing

Answer

Sustained manual compression for 30–45 minutes is standard practice for venous cannula sites, followed by a firm pressure dressing.

ECMO - Extracorporeal Membrane Oxygenation Practice Test

ECMO - Extracorporeal Membrane Oxygenation Practice Test

ECMO Weaning and Decannulation 2