ECMO - Extracorporeal Membrane Oxygenation Weaning and Decannulation Questions and Answers

Question 1

A 55-year-old patient on Veno-Venous (VV) ECMO for severe ARDS has shown significant improvement in lung compliance and chest X-ray findings.
The clinical team decides to perform a liberation trial.
What is the most appropriate initial step in this process?

Accepted Answer

Systematically reduce the sweep gas flow to zero while maintaining ECMO blood flow.

Answer

Gradually decrease ECMO blood flow to a minimal level (e.g., 1 L/min).

Answer

Discontinue all sedation to assess neurological readiness.

Answer

Increase the PEEP on the mechanical ventilator to 20 cm H2O.

Question 2

During a weaning trial from Veno-Arterial (VA) ECMO, the primary goal of reducing circuit blood flow is to assess the native heart's ability to handle what physiological change?

Accepted Answer

Increased preload and afterload.

Answer

Decreased systemic vascular resistance.

Answer

Reduced coronary artery perfusion.

Answer

Improved oxygenator efficiency.

Question 3

Which of the following is the most definitive sign that a patient is failing a VA ECMO weaning trial after ECMO flows have been reduced?

Accepted Answer

A rise in pulmonary capillary wedge pressure (PCWP) to >18 mmHg and a non-opening aortic valve on echocardiogram.

Answer

A slight increase in the patient's heart rate from 80 to 95 bpm.

Answer

A decrease in central venous pressure (CVP) from 12 to 8 mmHg.

Answer

An increase in the patient's native cardiac output by 1 L/min.

Question 4

A patient on VV ECMO is undergoing an "off-sweep" trial. After 30 minutes with the sweep gas turned off, an arterial blood gas (ABG) is drawn. Which of the following ABG results would indicate the patient has failed the trial and is not ready for decannulation?

Accepted Answer

pH 7.21, PaCO2 75 mmHg, PaO2 90 mmHg

Answer

pH 7.38, PaCO2 42 mmHg, PaO2 85 mmHg

Answer

pH 7.45, PaCO2 35 mmHg, PaO2 150 mmHg

Answer

pH 7.35, PaCO2 45 mmHg, PaO2 78 mmHg

Question 5

A 60-year-old male is decannulated after 10 days of femoral Veno-Arterial (VA) ECMO. The arterial cannulation site was repaired surgically. Four hours post-procedure, the patient's right foot becomes cool and pale, with non-palpable pedal pulses confirmed by Doppler silence. What is the most likely cause of these findings?

Accepted Answer

Acute arterial thrombosis or stenosis at the cannulation repair site.

Answer

Venous air embolism from the decannulation site.

Answer

Phlegmasia cerulea dolens due to a massive deep vein thrombosis.

Answer

Systemic inflammatory response syndrome from the ECMO run.

Question 6

A patient has been successfully weaned from peripheral Veno-Venous (VV) ECMO. The team is preparing for decannulation at the bedside. Which of the following is a critical preparatory step to minimize the risk of bleeding complications?

Accepted Answer

Ensuring anticoagulation has been held and coagulation parameters are in a safe range.

Answer

Administering a bolus of unfractionated heparin to prevent thrombus dislodgement.

Answer

Maximizing ECMO blood flow just prior to cannula removal.

Answer

Placing the patient in a steep Trendelenburg position to prevent air embolism.