A liver transplant is a surgical procedure performed to replace a diseased liver with a healthy liver from another person. The liver may come from a deceased organ donor or from a living donor. Family members or individuals who are unrelated but make a good match may be able to donate a portion of their liver. This type of transplant is called a living transplant. Individuals who donate a portion of their liver can live healthy lives with the remaining liver.
An entire liver may be transplanted, or just a section. Because the liver is the only organ in the body able to regenerate, a transplanted portion of a liver can rebuild to normal capacity within weeks.
A liver transplant is recommended for individuals who have serious liver dysfunction and will not be able to live without having the liver replaced. The most common liver disease for which transplants are done is cirrhosis. Other diseases may include the following:
- acute hepatic necrosis
- biliary atresia
- metabolic disease
- liver cancers
- autoimmune hepatitis
- liver damage from overdose of medications toxic to the liver
The majority of livers that are transplanted come from organ donors who have died. These organ donors are adults or children who have become critically ill (often due to an accidental injury) and have died as a result of their illness. If the donor is an adult, he/she may have agreed to be an organ donor before becoming ill. Parents or spouses can also agree to donate a relative's organs. Donors can come from any part of the United States. This type of transplant is called a cadaveric transplant.
An individual receiving a transplant may either get a whole liver, or a segment of one. If an adult liver is available and is an appropriate match for two individuals on the waiting list, the donor liver can be divided into two segments and each part is transplanted. This is more often done in children than adults.
Living family members may also be able to donate a section of their liver. This type of transplant is called a living-related transplant. Individuals receiving a partial liver seem to do as well as those receiving a whole liver. Relatives who donate a portion of their liver can live healthy lives with the segment that remains.
Extensive testing must be done before an individual can be placed on the transplant list. Testing includes:
- psychological and social evaluation
- diagnostic tests
- blood tests
Blood tests are done to gather information that will help determine how urgent it is that an individual is placed on the transplant list, as well as ensure the individual receives a donor organ that is a good match. These tests may include:
- liver enzymes
Elevated levels of liver enzymes can alert physicians to liver damage or injury, since the enzymes leak from the liver into the bloodstream under these circumstances.
- bilirubin
Bilirubin is produced by the liver and is excreted in the bile. Elevated levels of bilirubin often indicate an obstruction of bile flow or a defect in the processing of bile by the liver.
- albumin, total protein, and globulin
Below-normal levels of proteins made by the liver are associated with many chronic liver disorders.
- clotting studies, such as prothrombin time (PT) and partial thromboplastin time (PTT)
Tests that measure the time it takes for blood to clot are often used prior to liver transplantation. Blood clotting requires vitamin K and proteins made by the liver. Liver cell damage and bile obstruction can both interfere with proper blood clotting.
Other blood tests will help improve the chances that the donor organ will not be rejected. They may include:
- your blood type
Each person has a specific blood type: type A+, A -, B+, B -, AB+. AB -, O+, or O -. When receiving a transfusion, the blood received must be a compatible type with an individual's type of blood or an allergic reaction will occur. The same allergic reaction will occur if the blood contained within a donor organ enters an individual's body during a transplant.
- viral studies
These tests determine if you have viruses that may increase the likelihood of infecting the donor organ, such as cytomegalovirus (CMV) and Epstein-Barr virus (EBV).
Diagnostic tests may include any of the tests that have been done to evaluate the extent of the disease, including the following:
- abdominal ultrasound (Also called sonography.) - a diagnostic imaging technique which uses high-frequency sound waves and a computer to create images of blood vessels, tissues, and organs. Ultrasounds are used to view internal organs as they function, and to assess blood flow through various vessels.
- liver biopsy - a procedure in which tissue samples from the liver are removed (with a needle or during surgery) from the body for examination under a microscope.
There is no definite answer to this question. Sometimes, individuals wait only a few days or weeks before receiving a donor organ. If no living-related donor is available, it may take months or years on the waiting list before a suitable donor organ is available. Unfortunately, some people die before an acceptable donor organ can be found.
Each transplant team has their own specific guidelines regarding waiting on the transplant list and being notified when a donor organ is available. In most instances, you will notified by phone or pager that an organ is available. You will be told to come to the hospital immediately so you can be prepared for the transplant.
Rejection is a normal reaction of the body to a foreign object. When a new liver is placed in a person's body, the body sees the transplanted organ as a threat and tries to attack it. The immune system makes antibodies to try to kill the new organ, not realizing that the transplanted liver is beneficial. To allow the organ to successfully live in a new body, medications must be given to trick the immune system into accepting the transplant and not thinking it is a foreign object.
Medications must be given for the rest of the individual's life to fight rejection. Each person is individual, and each transplant team has preferences for different medications. The anti-rejection medications most commonly used include:
- Cyclosporine
- Tacrolimus
- Prednisone
The doses of these medications may change frequently, depending upon your response. Because anti-rejection medications affect the immune system, individuals who receive a transplant will be at higher risk for infections. A balance must be maintained between preventing rejection and making you very susceptible to infection. Blood tests to measure the amount of medication in the body are done periodically to make sure you do not get too much or too little of the medications. White blood cells are also an important indicator of how much medication you may need.
This risk of infection is especially great in the first few months because higher doses of anti-rejection medications are given during this time. You will most likely need to take medications to prevent other infections from occurring. Some of the infections you will be especially susceptible to include oral yeast infection (thrush), herpes, and respiratory viruses.
The following are the most common symptoms of rejection. However, each individual may experience symptoms differently. Symptoms may include:
- fever greater than 100° F
- jaundice - yellowing of the skin and eyes.
- dark urine
- itching
- abdominal swelling or tenderness
- fatigue
- irritability
- headache
The symptoms of rejection may resemble other medical conditions or problems. Consult your transplant team with any concerns you have.
Living with a transplant is a life-long process. Medications must be given that trick the immune system so it will not attack the transplanted organ. Other medications must be given to prevent side effects of the anti-rejection medications, such as infection. Frequent visits to and contact with the transplant team are essential.
There is no good answer to how long an individual can be expected to live after a liver transplant. Each person is different and every transplant is different. Results improve continually as physicians and scientists learn more about how the body deals with transplanted organs and search for ways to improve the success of transplantation.
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