ECMO - Extracorporeal Membrane Oxygenation Veno-Venous (VV) ECMO Management Questions and Answers

Question 1

A 45-year-old patient on VV ECMO for ARDS has shown significant radiological improvement and enhanced native lung gas exchange.
The team plans to initiate a weaning trial.
Which of the following is the most appropriate first step to assess the patient's readiness for liberation?

Accepted Answer

Gradually reduce the sweep gas flow rate while closely monitoring the patient's PaCO2.

Answer

Immediately clamp the circuit for 30 minutes to simulate decannulation.

Answer

Stop all sweep gas flow abruptly to perform a 'zero-sweep' trial.

Answer

Decrease the ECMO blood flow rate to 1 L/min to minimize support.

Question 2

A patient on VV ECMO is receiving a continuous infusion of unfractionated heparin (UFH). Which laboratory test is considered the most specific for monitoring the therapeutic effect of heparin, especially in critically ill patients who may have underlying coagulopathies or heparin resistance?

Accepted Answer

Anti-Factor Xa (Anti-Xa) level

Answer

Activated Clotting Time (ACT)

Answer

Prothrombin Time (PT/INR)

Answer

Activated Partial Thromboplastin Time (aPTT)

Question 3

Which of the following best describes the primary goal of mechanical ventilation for a patient fully supported on VV ECMO for severe ARDS?

Accepted Answer

To promote lung rest and minimize ventilator-induced lung injury (VILI).

Answer

To achieve a normal PaO2 by using high levels of PEEP and FiO2.

Answer

To maximize minute ventilation to assist the ECMO circuit with CO2 clearance.

Answer

To ensure the patient remains apneic to prevent patient-ventilator asynchrony.

Question 4

A patient on a stable femoro-jugular VV ECMO configuration for severe pneumonia develops acute hypoxemia (SpO2 drops from 95% to 86%). The ECMO circuit is functioning well, with a high post-oxygenator PaO2 and no signs of recirculation. Which patient-related factor is the most likely cause of this deterioration?

Accepted Answer

A sudden increase in the patient's native cardiac output.

Answer

Development of oxygenator membrane failure.

Answer

A decrease in the sweep gas flow rate.

Answer

Migration of the reinfusion cannula.

Question 5

During routine monitoring of a patient on VV ECMO, which of the following laboratory values is the most sensitive and direct indicator of circuit-induced red blood cell damage (hemolysis)?

Accepted Answer

Plasma-free hemoglobin (PFH)

Answer

Serum lactate dehydrogenase (LDH)

Answer

Haptoglobin

Answer

Total bilirubin

Question 6

A patient is supported with a dual-lumen single cannula via the right internal jugular vein for VV ECMO. The clinical team notes that the pre-membrane (drainage) oxygen saturation is rising, while the patient's systemic arterial saturation (SpO2) is simultaneously falling. This pattern is most indicative of:

Accepted Answer

Significant recirculation due to cannula malposition.

Answer

Improving native lung function.

Answer

Worsening right ventricular failure.

Answer

Impending oxygenator failure.