ECMO Circuit Components and Management 2

Question 1

What is the primary purpose of the raceway tubing in a centrifugal ECMO pump?

Accepted Answer

To serve as the segment compressed by the pump head

Answer

Raceway tubing is the specialized, crush-resistant segment that sits within a roller pump head and is repeatedly compressed to propel blood.

Question 2

Which ECMO circuit component is responsible for removing CO2 from the patient's blood?

Accepted Answer

Oxygenator membrane

Answer

The oxygenator membrane facilitates both oxygen delivery and CO2 removal via diffusion across hollow fiber membranes.

Question 3

When a 'chatter' or 'flutter' is observed in the venous drainage tubing, the most likely cause is:

Accepted Answer

Excessive pump flow rate relative to venous return

Answer

Tubing chatter indicates inadequate venous return relative to the pump's demand, causing intermittent collapse and re-expansion of the drainage line.

Question 4

The sweep gas flow rate in ECMO primarily controls which parameter?

Accepted Answer

CO2 removal

Answer

Sweep gas flow (the gas flowing through the oxygenator fiber lumen) is the primary determinant of CO2 clearance from the blood.

Question 5

What is the recommended strategy when air is detected in the ECMO circuit?

Accepted Answer

Clamp the circuit, stop the pump, and remove air before restarting

Answer

Air entry requires immediate circuit clamping and pump stoppage to prevent air embolism, followed by controlled de-airing before circuit restart.

ECMO - Extracorporeal Membrane Oxygenation Practice Test