Coronary Artery Bypass Graft Surgery: How It Is Done - Topic Overview
Putting you on the heart-lung bypass machine
After your coronary arteries have been exposed and a usable blood
vessel segment has been harvested, your surgical team may
place you on a heart-lung bypass machine. Alternately,
your surgical team may perform the operation while your heart is beating. If
you are placed on the heart-lung bypass machine, your heart will be temporarily
stopped during the surgery so your surgeon can perform surgery on
your coronary arteries. The heart-lung bypass machine does the work of your
heart and lungs so that all the parts of your body still receive the
oxygen-rich blood they need to survive.
While the ventilator physically inflates and deflates your lungs, the
bypass machine performs the lungs' main job of adding oxygen and removing
unwanted gases from your blood. In addition, the machine circulates that blood
through your body.
After the heart-lung machine has been set up, the blood flowing from
your heart to the rest of your body will be stopped by clamping the aorta and
will be rerouted through the heart-lung bypass machine. Your anesthesiologist will then
inject a medication through your IV (or squirt it directly onto your heart) to
stop your heartbeat immediately. Your heart will not beat again until the new
grafts have been put in place.
Bypassing your diseased coronary arteries
will start to operate on the coronary arteries. The harvested vein
in the sterile saline solution is cut into appropriate lengths. Your surgeon
will attach one end of the blood vessel to the aorta (or to the coronary
artery) and the other end onto a portion of the coronary artery past the
location in the artery where there is narrowing or blockage.
In the case of the LIMA or RIMA, one end remains attached to your
chest wall and the other end is connected to the coronary artery. Regardless of
which type of blood vessel is used, oxygen-rich blood is rerouted around the
narrowed or blocked section of the coronary artery and into a healthy section
where it can feed into the heart muscle.
Preventing blood loss during surgery
During the surgery, blood may spill into your chest cavity as small
blood vessels are cut. To prevent this blood from interfering with surgery, a
nurse or surgeon's assistant will use a suction device (which looks like a
large plastic straw) to suck up the blood. This device is
attached to the heart-lung machine. So if you are on this machine,
blood that is sucked up is actually returned to your body several
seconds later so that you don't lose too much blood. Despite this effort,
though, about half of the people who have CABG surgery end up needing a blood