Similar to the machine used in open-heart surgery, ECMO uses a pump to take over the work of the heart and an oxygenator (artificial lung) to take over the work of the lungs. First, one or two cannulas (large tubes placed in arteries or veins) are placed in the patient's neck and/or groin(s). Based on the patient's illness, the ECMO team will decide what type of ECMO to use, the number of cannulas needed, and where they will be placed. The cannulas
are like really large IV's that allow blood to be taken out of the body and pushed through the ECMO circuit (tubing). Once the blood leaves the body and enters the ECMO tubing, it is pumped through an oxygenator, or artificial "lung," where oxygen (good air) is added to the blood and carbon dioxide (bad/waste air) is removed. The treated blood is then warmed before returning to the patient's body.
This diagram shows a typical ECMO circuit with blue (without oxygen) blood becoming red (oxygenated) by the artificial lung outside the body. The Pump provide the power to move the blood around. The hemofilter can act as an artificial kidney, and heparin is the drug that helps keep the blood from clotting when it's outside the body.