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The liver is the largest organ in the body. It is found high
in the right upper abdomen, behind the ribs. It is a very complex
organ and has many functions. They include:
- Storing energy in the form of sugar (glucose)
- Storing vitamins, iron, and other minerals
- Making proteins, including blood clotting factors, to keep
the body healthy and help it grow
- Processing worn out red blood cells
- Making bile which is needed for food digestion
- Metabolizing or breaking down many medications and
alcohol
- Killing germs that enter the body through the intestine
The liver also has a remarkable power to regenerate itself.
However, there are illnesses that can cause permanent and
irreversible damage to the liver. Liver transplantation has
become a standard treatment for a patient whose liver no longer
functions well enough to maintain life. This revolutionary
treatment has moved from research and the first actual transplant
in the 1960s, to a standard form of therapy in the 1990s.
There are two main reasons why liver transplants have become so
successful. There have been major advances in surgical
techniques, and new drugs are now available to prevent rejection
of the new liver.
Reasons for Liver Transplantation
Medical treatment for liver diseases and liver damage is
always the first choice of therapy. The only reason to perform a
liver transplant is that all other forms of treatment have been
unsuccessful, and the patient's liver can no longer support
life. This is called end stage liver disease. There have been
over 60 different liver diseases treated with liver
transplantation. However, there are several conditions that are
more commonly treated with this procedure. They are frequently
conditions that cause chronic or continuing liver inflammation.
As the inflammation heals, fibrous tissue forms, much like a scar
forms when a cut in the skin heals.
Severe and advanced scarring of the liver is called cirrhosis.
Cirrhosis is not reversible and leads to end stage liver disease.
The following conditions are the most common causes of end stage
liver disease:
- Chronic viral hepatitis B and C
- Alcohol related liver disease
- Autoimmune hepatitis
- Primary sclerosing cholangitis
- Primary biliary cirrhosis
- Steatohepatitis
- Liver disorders inherited or present at birth
- Drug induced liver damage
In children, the most common cause of liver failure is biliary
atresia. This is a condition in which the bile ducts fail to
develop. These ducts carry bile from the liver to the intestine.
If there are no ducts, the bile backs up in the liver and causes
damage. Biliary atresia is usually present at birth.
Special Considerations
Alcoholism is a common cause of end stage liver disease.
Although these patients are not denied a liver transplant, all
transplant centers will insist on a thorough psychological
evaluation beforehand. They also require treatment of the
alcoholism, proven abstinence for at least six months, and good
prospects that the patient will continue to abstain from alcohol.
A transplanted liver will become severely damaged by alcohol just
like the old one.
Most patients infected with hepatitis B and some with
Hepatitis C recover completely with no further liver damage.
However, some will develop chronic hepatitis leading to cirrhosis
and end stage liver disease. This is more common with Hepatitis
C. A liver transplant under these circumstances is difficult to
manage because the new liver almost always becomes infected with
these viruses. Ongoing treatment is usually necessary to keep the
new liver healthy.
Most cancers of the liver develop in other parts of the body
and spread to the liver. These patients are never transplanted
because their cancer is not curable. Occasionally, cancer
develops first in the liver. This is called a primary cancer or
hepatoma. When a primary liver cancer is identified early, a
liver transplant will be performed. However, long- term survival
is less common in this case than with transplants for other
conditions.
Transplant Centers
Transplant centers are very specialized facilities that are
usually located at university teaching hospitals or large medical
centers. They require a large staff of surgeons and other
professionals to evaluate and select patients, and perform
surgery and follow-up care. In addition, they must maintain close
communications with transplant candidates and the national
network that rations the livers as they become available. All
transplant centers have equal access to technical skills and
drugs to prevent rejection, so survival rates depend a great deal
on the underlying disease of the recipient. Primary cancer of the
liver has the lowest long-term survival at about 50%-60%. Primary
biliary cirrhosis and primary sclerosing cholangitis have
survival rates of over 90%. Transplants that are performed for
other diseases have survival rates ranging somewhere in between
these figures.
Unfortunately, there are more patients who need a new liver
than there are donors. Choosing who gets a liver can be
difficult, so a fair system of allocation had to be developed.
There is an organization called United Network for Organ Sharing
(UNOS) in Richmond, VA. UNOS provides a distribution plan to each
transplant center, based on population. Donor livers almost
always come from individuals who have suffered fatal brain damage
due to trauma, rather than disease. Ideally, physicians and
patients should be able to plan and perform a transplant before
the patient reaches end stage liver disease. However, because of
the lack of donor livers, the choice of who gets a new liver now
depends on how critically ill the patient is. Other
considerations, such as a patient's psychological make-up,
are a part of the decision. For example, an unreformed alcoholic
will have little chance for a liver transplant. The patient's
family situation and support at home are also factors. Often a
panel of lay people and medical personnel will help make the
choice at each transplant center. Once patients are selected as
candidates, they are placed on the active transplant list and
given a beeper to wear at all times. This is so they can get to
the transplant center at a moment's notice. If for some
reason the patient selected is not suitable for the operation at
the time a liver becomes available, there is always a back-up
candidate for each donor liver.
Surgery
Liver transplantation is a complicated process. There are
really three operation's involved. The first is the removal
of the liver from the donor. If the liver is donated at a
different location, it must be transferred to the transplant
center under sterile refrigerated conditions within 8 to 20
hours. The second operation is the removal of the diseased liver
from the patient, and the third is the operation to insert and
connect the new liver. The operations on the recipient are so
detailed they require a long time to complete. But, the team of
surgeons, nurses, and support staff are now very experienced in
the technique. The new liver is attached to the various blood
vessels and bile ducts. When the surgery is completed, the
patient goes to the recovery area.
Recovery
Recovery begins with several weeks in the hospital.
Immediately after surgery, the patient is in intensive care for a
time. This is so there can be continual monitoring for any
infection, rejection, or poor functioning of the new liver.
Rejection occurs because the transplanted liver is recognized as
foreign by the body. This is the body's normal reaction to
any foreign substance. The body's rejection of the transplant
would cause inflammation and damage to the new liver.
Because of this, medications must be given to calm the
rejection reaction in the body. Long-term treatment against
rejection is always necessary.
There are three main medications used to prevent rejection.
One is a cortisone drug, usually prednisone (trade names:
Deltazone, Orasone). It is often used in a low dose. The side
effects are fluid build-up and puffiness of the face. A more
serious side effect is a change in the bones. Prednisone causes a
loss of calcium that can lead to osteoporosis and damage to
joints such as knees, hips, and shoulders. A second drug is
called Sandimmune. Sandimmune is difficult to regulate and can
produce high blood pressure, kidney damage, and occasionally
growth of body hair. A third drug is Prograf. This drug has been
dramatic in providing successful transplants with the lowest side
effects. But even here, kidney damage can occur. It is easy to
see why close follow-up is needed for patients on these drugs.
Frequent blood tests are required to monitor the patient's
progress and reduce side effects.
As recovery progresses, the patient is released to outpatient
status, but must stay close to the transplant center for daily
visits and blood testing. Finally as things stabilize, the
patient is sent home to the care of his/her personal physician.
Usually, follow-up is maintained with the patient's
physicians at the transplant center. Once patients have
recovered, they can resume normal physical and sexual activities.
Even vigorous exercise is possible after full recovery, but this
should only be done after discussion with the physician. There
are few dietary restrictions. The patient is often advised to
restrict salt (sodium) intake. A well- balanced diet with
adequate protein is necessary. For reasons that are not clear,
obesity frequently becomes a problem with liver transplant
patients. To avoid this problem, patients should take control of
their calorie intake early on.
As the body becomes familiar with the transplanted liver, the
amount of medicine needed to control rejection can be adjusted
and usually reduced. However, most liver transplant patients will
always have to take at least some medication.
Liver Donation
It is very important that more livers become available for
donation. All healthy people are encouraged to make arrangements
to become liver donors if they are ever in a situation that would
make this possible. Generally, there are no restrictions on age,
sex, or race. The only matching requirements for livers are that
the donor and recipient must be about the same size and have
compatible blood types. Some states allow people to register to
become organ donors when they apply for or renew a driver's
license. Anyone wishing to become an organ donor should carry an
organ donor card or an ID card with an organ donor sticker
attached. It is important to discuss organ donation with family
members, because they must always give consent when the
circumstances take place.
Summary
Liver transplantation is an important move forward in the
treatment of severe liver disease. It has opened a new world for
patients who otherwise were destined to die from their liver
disease. The operation is a major one, and there are still
problems associated with medications used to prevent rejection.
But overall, patients can usually expect a good outcome with
return to normal activities.
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