ECMO Patient Monitoring and Assessment 4 — Questions and Answers
Question 1: Which finding on echocardiography is most indicative of a properly functioning ECMO circuit with adequate unloading of the right ventricle in VV-ECMO?
- Hyperdynamic LV function
- Reduced RV dilation and improved septal position (Correct answer)
- Mitral regurgitation
- Pericardial effusion
Correct answer: Reduced RV dilation and improved septal position
In VV-ECMO, improving RV dilation and restoration of normal interventricular septal position indicate reduced RV afterload from improved oxygenation and CO2 removal.
Question 2: A patient on VA-ECMO develops a new pulseless rhythm on telemetry but arterial line shows a stable waveform. What is the most likely explanation?
- Ventricular fibrillation with full ECMO support (Correct answer)
- Lead artifact
- Myocardial recovery
- Circuit air embolism
Correct answer: Ventricular fibrillation with full ECMO support
VA-ECMO can maintain arterial perfusion even during ventricular fibrillation; the arterial waveform reflects ECMO-generated continuous flow rather than native cardiac output.
Question 3: Serial chest X-rays in a VV-ECMO patient show progressive improvement in bilateral infiltrates. This finding suggests:
- Oxygenator failure
- Lung rest and potential recovery (Correct answer)
- Worsening ARDS
- Circuit recirculation
Correct answer: Lung rest and potential recovery
Clearing bilateral infiltrates on serial imaging indicate lung rest from reduced ventilator settings enabled by ECMO, suggesting potential native lung recovery.
Question 4: Which neurological assessment tool provides real-time detection of cerebral ischemia or seizure in ECMO patients?
- MRI brain
- Continuous EEG monitoring (Correct answer)
- Lumbar puncture
- Cranial CT scan
Correct answer: Continuous EEG monitoring
Continuous EEG is the gold standard for detecting subclinical seizures and ischemic changes in real time at the bedside in ECMO patients at neurological risk.
Question 5: Which daily laboratory panel is essential for monitoring coagulopathy in ECMO patients?
- CBC, CMP, thyroid panel
- CBC, PT/INR, aPTT, fibrinogen, anti-Xa level (Correct answer)
- Liver function tests and albumin
- Serum electrolytes and glucose only
Correct answer: CBC, PT/INR, aPTT, fibrinogen, anti-Xa level
Daily assessment of CBC, coagulation studies, fibrinogen, and anti-Xa levels allows detection of consumptive coagulopathy, bleeding risk, and heparin effect during ECMO.
Question 6: In VA-ECMO, pulse pressure monitoring on the arterial line is used to assess:
- Oxygenator efficiency
- Native cardiac contractility and LV ejection (Correct answer)
- Anticoagulation adequacy
- Venous cannula position
Correct answer: Native cardiac contractility and LV ejection
Progressive widening of pulse pressure on the arterial waveform during VA-ECMO indicates improving native LV systolic function, a sign of cardiac recovery.
Question 7: Which finding would prompt the ECMO team to assess for heparin-induced thrombocytopenia (HIT) in an ECMO patient?
- Hemoglobin drop below 9 g/dL
- Platelet count falling by >50% from baseline despite adequate heparin (Correct answer)
- Elevated lactate above 4 mmol/L
- Arterial oxygen saturation below 90%
Correct answer: Platelet count falling by >50% from baseline despite adequate heparin
A platelet count drop of >50% from baseline in a heparin-exposed patient raises concern for HIT, which can cause paradoxical thrombosis requiring alternative anticoagulation.
ECMO Patient Monitoring and Assessment 4
Which finding on echocardiography is most indicative of a properly functioning ECMO circuit with adequate unloading of the right ventricle in VV-ECMO?