How does ECMO work?

Once the tubes are in place the ECMO circuit can be connected. Although the ECMO circuit and machines may seem frightening at first, we hope that when you understand how they work you will be less worried.

• First, dark blood, which has low levels of oxygen, flows from your child through the circuit into a reservoir.
• The blood is then pumped from the reservoir through the oxygenator, or artificial lung.
• After going through the oxygenator the blood becomes bright red, due to higher levels of oxygen.
• The blood then goes through a heat exchanger to be warmed.
• And then back into the child (through a vein or an artery).

Note that this image shows a type of blood pump called a "roller pump". We now use a smaller, more modern type of pump called a "centrifugal pump" that has many advantages for the patient.