How long do you have to be connected to the heart-lung machine?
How long you have to be connected to the heart–lung machine depends very much on the type of heart surgery that is performed. In general, this time is kept as short as possible to avoid complications as far as possible. At the beginning of the operation, the chest is first opened and the heart is well exposed.
After the necessary preparations, the heart is connected to the heart-lung machine and then a potassium-rich cardioplegic solution is used to artificially stop the heart. While the heart-lung machine takes over the function of the now still heart, the heart can be operated on.Once all the surgical steps have been performed, the heart is stimulated again so that it beats independently and gradually less blood is passed through the heart-lung machine until it can be completely removed. This procedure is roughly identical for most operations, so that the duration depends largely on the surgical method and can vary greatly. Periods of two to three hours on a heart-lung machine are considered safe, as no permanent damage to the heart remains during this time.
What is the maximum length of time you can be connected to the heart-lung machine?
A heart-lung machine can take over the function of the heart for several days. This is used when the heart cannot resume its entire pumping function after the surgical steps have been performed. Connecting the heart to the heart-lung machine for several days supports the heart until it is fully functional again.
Periods beyond that prove to be problematic because they are associated with increasing rates of side effects. In addition to acute therapy, bypass surgery can be performed in a later phase of a heart attack. Such an operation is performed when three coronary arteries far from the trunk or two vessels near the trunk are partially or completely blocked and this has led to symptoms such as a heart attack.
Under ” maximum connection time for a bypass operation” the necessity of the heart-lung machine for this operation is explained in more detail. A bypass operation is performed when one of the coronary arteries is no longer sufficiently permeable, so that the supply to the heart cannot be guaranteed. While a new artery or vein is sewn onto the heart and connected to the trunk of the coronary vessels, the heart is immobilized and connected to a heart-lung machine in the classic operation.
The entire operation lasts about 4-8 hours, which is influenced by various factors. During this period, however, the heart is not connected to the heart-lung machine for the entire time, but only as long as the vessels are operated on. Newer minimally invasive surgical methods can even do without an artificial cardiac arrest and heart-lung machine.
The section to be operated on is held in place with a U-shaped bracket and can be stabilized so that surgery on the vessels is possible. The heart-lung machine represents a pure replacement circuit and cannot keep the body alive for a long time. This replacement is only sufficient for the basic functions of the body and is only used during anesthesia or an artificial coma. The coma or anesthesia are therefore an integral part of therapy with a heart-lung machine. Affected patients are normally only awakened from the coma after resuming normal bodily functions.
