ECMO Veno-Venous (VV) ECMO Management 3

Question 1

A VV ECMO patient has adequate oxygenation but develops progressive hypercapnia despite maximum sweep gas settings. What is the next step?

Accepted Answer

Evaluate for membrane oxygenator clot or plasma leak

Answer

Plasma leak or thrombus within the oxygenator impairs gas exchange efficiency, causing CO2 retention despite maximal sweep settings.

Question 2

Which anticoagulation monitoring strategy is most commonly used during VV ECMO in adults?

Accepted Answer

Activated partial thromboplastin time (aPTT) with unfractionated heparin

Answer

Unfractionated heparin titrated to aPTT (typically 60–80 seconds) is the most widely used anticoagulation strategy in adult VV ECMO.

Question 3

During VV ECMO, a patient develops acute hemolysis (plasma-free hemoglobin >500 mg/dL). What is the FIRST action?

Accepted Answer

Inspect the circuit for thrombus, kinks, or high negative inlet pressure

Answer

Hemolysis on ECMO is often caused by mechanical factors (thrombus, kinking, cavitation from excessive negative pressure), which must be identified and corrected first.

Question 4

What is the recommended target activated clotting time (ACT) range for most adult VV ECMO patients using unfractionated heparin?

Accepted Answer

160–200 seconds

Answer

Most centers target an ACT of 160–200 seconds on VV ECMO, balancing thrombosis prevention against bleeding risk.

Question 5

A VV ECMO patient requires a blood transfusion. Which hemoglobin threshold is most appropriate for initiating transfusion in a stable patient?

Accepted Answer

Hgb < 8 g/dL

Answer

Most ECMO centers use a hemoglobin threshold of 8 g/dL for transfusion, as higher hemoglobin improves oxygen-carrying capacity on ECMO support.

ECMO - Extracorporeal Membrane Oxygenation Practice Test

ECMO - Extracorporeal Membrane Oxygenation Practice Test

ECMO Veno-Venous (VV) ECMO Management 3