What is a liver transplant?
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.
The liver is the body's principle chemical factory. It receives all nutrients, drugs, and toxins absorbed from the intestines and performs the final stages of digestion, converting food into energy and replacement parts for the body. The liver also filters the blood of all waste products, removes and detoxifies poisons and excretes many of these into the bile. It processes other chemicals for excretion by the kidneys. The liver is also an energy storage organ, changing food energy to a chemical called glycogen that can be rapidly converted to fuel.
As the liver fails, all of its functions diminish. Nutrition suffers, toxins build up, and waste products accumulate. Scar tissue builds up on the liver if disease is of long duration. As the liver scars, blood flow is progressively restricted in the portal vein, which carries blood from the stomach and abdominal organs to the liver. The resulting high blood pressure (hypertension) causes swelling of and bleeding from the blood vessels of the esophagus. Severe jaundice, fluid accumulation in the abdomen (ascites), and deterioration of mental function, due to the build-up of toxins in the blood (liver encephalopathy), eventually occur, leading to death.
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 acute hepatic necrosis, biliary atresia, metabolic disease, liver cancers, and autoimmune hepatitis.
Fulminant liver failure most commonly happens during acute viral hepatitis, but it is also the result of mushroom poisoning by Amanita phalloides and toxic reactions to some medicines, like an overdose of acetaminophen. This is a special category of candidates for liver transplant because of the speed of their disease and the immediate need of treatment.
The first human liver transplant was performed in 1963, and since then, thousands of liver transplants are done every year. Since the introduction of of cyclosporine (a drug that suppresses the immune response that rejects the donor organ), success rates for liver transplantation have reached 85%.
Liver transplant may be from cadavers or living donors and involve the whole liver, a reduced liver or a liver segment. The donor livers in transplants were initially from cadavers. Donor livers from live donors are now in increasing use. Most transplants involve the whole organ. A reduced liver transplant may be done if the donor liver is too large for the recipient. In segmental transplants, a segment (often a lobe) of the liver is transferred from a living donor to a recipient. The first such recipients were children. Now some are adults. The liver segments in the donor and the recipient grow back to full size within about a month.