A heart-lung -or cardiopulmonary bypass – machine is used during heart surgery to deliver oxygenated blood to the body while the heart is being repaired.
When the heart is functioning normally, oxygen-poor blood from the body, shown here in blue, returns to the right side of the heart and is then pumped to the lungs where it absorbs oxygen. The oxygen-rich blood, shown here in red, returns from the lungs to the left side of the heart and is then pumped to the body to deliver oxygen to the tissues.
The heart-lung machine allows blood to bypass the heart and lungs. Tubes are placed into the large veins that bring oxygen-poor blood back to the heart in order to drain this blood directly into the reservoir of the heart-lung machine. The blood is oxygenated by an artificial lung attached to the reservoir. The heart-lung machine then delivers blood to the body by pumping the oxygen-rich blood through a tube placed in the aorta. When the heart–lung machine is functioning, the heart can be stopped so surgery can be performed while the heart is still. Following the procedure the heart is restarted and the heart-lung machine tubing is removed.
Visit Heart Rhythm Society for more information.