CES ECMO Weaning & Decannulation 1 — Questions and Answers
Question 1: Which parameter is most important to assess before attempting VV ECMO weaning?
- Improvement in native lung compliance and gas exchange on reduced ECMO support (Correct answer)
- Normalization of serum lactate
- Absence of fever for 24 hours
- Resolution of chest X-ray infiltrates
Correct answer: Improvement in native lung compliance and gas exchange on reduced ECMO support
Improved native lung gas exchange and compliance on progressively reduced sweep gas and/or flow indicates readiness for VV ECMO weaning.
Question 2: During a VV ECMO weaning trial, sweep gas flow is typically reduced to assess:
- Circuit blood flow tolerance
- Native lung's ability to maintain gas exchange independently (Correct answer)
- Hemodynamic stability off ECMO
- Oxygenator membrane integrity
Correct answer: Native lung's ability to maintain gas exchange independently
Reducing sweep gas (CO2 removal drive) while monitoring SpO2 and PaCO2 tests whether the native lungs can sustain adequate gas exchange.
Question 3: For VA ECMO weaning, which hemodynamic parameter most reliably indicates cardiac recovery?
- Pulse pressure > 10 mmHg on arterial waveform (Correct answer)
- Mean arterial pressure > 65 mmHg on vasopressors
- Central venous pressure < 10 mmHg
- Urine output > 0.5 mL/kg/hr
Correct answer: Pulse pressure > 10 mmHg on arterial waveform
Return of pulsatility (pulse pressure >10 mmHg) on the arterial waveform indicates improved native cardiac output during VA ECMO.
Question 4: Which echocardiographic finding supports readiness for VA ECMO weaning?
- LVEF ≥ 20–25% with VTI > 10 cm (Correct answer)
- LVEF ≥ 50% with no regional wall motion abnormalities
- Normal diastolic function only
- Absence of pericardial effusion
Correct answer: LVEF ≥ 20–25% with VTI > 10 cm
An LVEF ≥ 20–25% with LVOT VTI > 10 cm suggests sufficient cardiac recovery to tolerate a weaning trial.
Question 5: A VA ECMO weaning trial is typically performed by:
- Clamping the circuit and observing for 30 minutes
- Gradually reducing ECMO flow while monitoring hemodynamics (Correct answer)
- Increasing sweep gas to reduce circuit oxygen delivery
- Removing the oxygenator from the circuit
Correct answer: Gradually reducing ECMO flow while monitoring hemodynamics
Stepwise reduction of VA ECMO flow while monitoring hemodynamics and end-organ perfusion is the standard weaning trial approach.
Question 6: What is the minimum recommended ACT range during a weaning trial to reduce thrombosis risk without excessive bleeding?
- 120–140 seconds
- 160–180 seconds (Correct answer)
- 200–220 seconds
- 240–260 seconds
Correct answer: 160–180 seconds
During weaning trials, maintaining ACT between 160–180 seconds balances circuit thrombosis prevention with hemorrhagic risk.
CES ECMO Weaning & Decannulation 1
Which parameter is most important to assess before attempting VV ECMO weaning?