What is ECMO?
ECMO (Extracorporeal Membrane Oxygenation) uses a heart-lung machine similar to the one used in open-heart surgery. There are two types of ECMO: Venoarterial (VA) ECMO uses an artery and a vein, venovenous (VV) ECMO uses one or two veins. The doctor decides which type your child needs. When a child goes on ECMO, the following things happen:
Before ECMO can begin, a pediatric surgeon places tubes, or cannulas, into large veins and/or arteries located on the right side of the neck or in the groin. Your child will be given medications to prevent pain and movement during the surgery. The surgery will happen in the Intensive Care Unit.
The number of tubes used depends on the type of ECMO your child needs. These vessels are called the internal jugular vein, the carotid artery, the femoral vein and the cephalad vein. Your child may have one special cannula placed into the internal jugular vein, depending on how big your child is. This cannula will do the job of the two cannulas.
The ECMO machine is made up of several parts: a pump, an artificial lung, a blood warmer and an arterial filter. The ECMO machine takes the blue blood (without oxygen) out of the right side of the heart and pumps it through the artificial lung (oxygenator). The blood is now red blood (with oxygen). This blood is warmed and filtered before returning to the child.
The ECMO machine does the work for your child’s lungs and/or heart and allows them time to heal. During the time your child is on ECMO, he is still connected to the ventilator. The ventilator is used to keep the lungs from collapsing while they get better.
At the beginning of the procedure, the ECMO machine does most of the work for the child’s heart and lungs. Even though your child looks much better, it is important to remember that the ECMO machine is doing the work the lungs can’t do.
To see if your child is getting better, a small amount of blood is drawn from the arterial line. This test (a blood gas) checks to see how much oxygen is present in the blood. As your child’s lungs begin to heal, the oxygen level in the blood improves. This allows us to turn down the ECMO machine slowly, to wean your child off ECMO. The machine is turned down until it is doing only a small portion of the work. At this time we may try to take your child off ECMO and measure the level of oxygen and carbon dioxide in the blood to see if the lungs are ready to work.
While your child is on ECMO he receives a medicine called heparin. Heparin keeps your child’s blood from clotting in the ECMO circuit. Heparin may cause your child to bleed while on ECMO. Special blood tests, (ACTs) are done every hour to check how fast the blood is clotting. When your child is taken off ECMO the heparin is stopped, and the time it takes your child’s blood to clot will return to normal in a few hours.
Babies are on ECMO for an average of five days. Older children and some infants may be on ECMO for weeks. The doctor and team determine how long it should take for your child to get better, but the time needed to recover is not always known.