Stage 3 Single Ventricle Palliation - Fontan Completion
After the second stage palliation, nearly half of all the blue, oxygen poor blood in the body (from the upper half of the body ) reaches the lung, without the help of a pumping chamber via the bidirectional glenn shunt.The rest, from the lower half of the body is still going to the only available pumping chamber and being pumped along with the red oxygen rich blood to the whole body. This arrangement is not accepted as a final solution. The stage 3 palliation is the final solution. In this stage, the remaining oxygen poor blue blood from the lower half of the body is also channeled to the lungs, without the help of a pumping chamber. This is generally done using an artificial tube which is connected during surgery to the inferior vena cava at one side and the pulmonary artery on the other side. As the artificial tube cannot grow, the procedure can be done only when the child is big enough to accommodate a large tube between the inferior vena cava and pulmonary artery. This procedure, called Fontan completion, is done generally when the child has gained a weight of around 15 kgs, 3-5 years of age. After Fontan completion, all the oxygen poor, blue blood is flowing directly to the lungs for adding oxygen. Red, oxygen rich blood is pumped by the only available pumping chamber to the whole of the body. After this surgery, the oxygen saturation of the child rises from 80-85% to 95% and above, near normal. The Fontan procedure may also be done for conditions such as hypoplastic left heart syndrome (HLHS), tricuspid atresia, and double outlet right ventricle.