Heart-lung transplant

From ArticleWorld

The heart-lung transplant is a special type of transplant that replace the lungs and the heart of the receiver in one operation. The operation is fairly uncommon because of the small number of donors.

Indications

Those who need such an operation are usually people who have life-threatening damage or dysfunctions to both the heart and the lungs. The most common causes include:

• Congenital problems that affect the lungs and the heart, being the most common cause.

• Pulmonary hypertension

• A new transplant, following after a failed first transplant

• Cystic Fibrosis

Some medical regulations require certain conditions -- that the receiver should be under a certain age (50-55 years in general), have no medical condition. These are required in order to insure that the receiver will be able to follow a post-operatory treatment with physical exercise and immunosupressives.

Procedure

The standard procedure includes placing the receiver under anesthesia. The donor's organs go through a final fitness check, and, if they are found suitable, the operation may begin.

The surgeon will make an incision that goes across the entire sternum. The skin edges are retracted, the sternum is cut to the middle and rib spreaders are installed, so that access is given to the heart and lungs.

After the heart and lungs are exposed, the patient must be connected to a machine that will circulate and oxygenate blood, while the transplant is being carried out. The malfunctioning lungs and heart are removed, with blood vessels cut as close to the organ as possible in case any trimming is required.

The delicate procedure of fitting the received organs begins. At first, they will begin inflating as they get warmer, approaching the body temperature. The most problematic part is giving functionality back to the heart, which may fibrillate at first, due to asynchronous contraction of muscle fibers. The general technique is to use small electric paddles that apply mild electric shocks in order to make the contractions correct.

The supporting machine is disconnected and, as soon as organs regain their normal functions, the chest is closed.

After the operation, several days of intensive care are required, and several drugs are administered. Follow-up visits are very frequent after the operation.

Risks

The risk of rejection is particularly high in this case, since the organs are very sensitive, and any failure can be life-threatening. The short-term survival rate is quite high, but the long term survive rate is of 54%, so only about half of the patients survive.