Indications and Procedures
Liver
transplantation is performed on individuals whose livers are severely diseased and unable to carry out normal liver functions. The most common cause of liver failure in adults is
cirrhosis, which results from alcohol and/or drug abuse. In this condition, the liver becomes filled with tough, nonfunctional scar tissue. Symptoms of cirrhosis, as well as other liver diseases, include abnormal levels of liver enzymes in the blood, jaundice, a lack of blood-clotting factors, the inability to dispose of bile, and the failure to detoxify metabolic by-products and other poisons, which can lead to coma and death. Other conditions that can lead to liver disease include hepatic
cancer, long-term hepatitis B infection, and obstruction of the bile passages in the liver.
The donor liver may be obtained from a recently deceased individual, or a section of the liver can be obtained from a living donor. In either case, the donated organ must be a close immunological match to reduce the chance of transplant rejection. A preoperative injection is given to the recipient to dry up internal fluids and promote drowsiness, and general anesthesia is administered. A vertical incision is made from just below the breastbone to the navel. Muscles are moved aside, and a second incision is made through the outer membranous lining of the body cavity, revealing the internal organs. Bypass tubes are inserted into the hepatic veins and connected to veins in the arm to divert the flow of blood from the liver. When this is completed, the hepatic veins are cut, and the liver and gallbladder are removed from the body cavity. The veins of the donor liver are connected to the recipient veins, and the bypass tubes are removed. The new liver is then connected to the intestine, and the incisions are closed.
Uses and Complications
Liver transplantation is performed only when the individual has no other chance for survival. Typically, there is a long waiting list for available organs. Certain factors such as blood type and protein markers on cell surfaces must be matched as closely as possible in order to avoid rejection by the recipient’s immune system. A liver from a recently deceased donor may be kept functioning only for five hours with specific cooling fluid, thus limiting its ability to be transported long distances. Because of the lack of available transplant organs and the necessity of compatibility, many people die before an appropriate organ becomes available. It is possible to transplant a segment of liver from a close relative; the liver can grow considerably and regenerate itself. This is a preferable situation and eliminates the pressure of transporting a donor liver between hospitals while attempting to keep it functioning.
After liver transplantation, the patient is kept in an intensive care unit for several days and in bed for at least a week. Pain from the incisions is alleviated with drugs. Rejection is the major danger, even with closely matched donor organs. Drugs such as cyclosporine are administered to suppress the immune system and, in most cases, must be taken for life. These immunosuppressive drugs inhibit the normal functioning of the immune system, thus making the individual much more susceptible to frequent—and more severe—infections, including bacterial, fungal, and viral infections. Other possible complications of the long-term use of immunosuppressive drugs include cataracts, impaired wound healing, peptic ulcers, and steroid-induced diabetes mellitus. About 20 percent of patients suffer graft rejection, obstruction of the arteries, or infection. In the case of serious complications, another transplantation may be the patient’s only hope for survival. In successful surgeries, patients are able to return to normal, active lives within a few weeks of the surgery.
Perspective and Prospects
The first successful liver transplantation procedure was performed in 1967. Nevertheless, this surgery was considered an experimental procedure until 1983, when a National Institutes of Health (NIH) conference on liver transplantation accepted it as a routine procedure. In 1984, more than 250 liver transplantations were performed in the United States. Within five years, that number increased dramatically, to 2,188 transplantation procedures performed in 1989; by 2002, the number had climbed to more than 5,300 transplants and has risen to an average of about 6,000 per year. Long-term results are steadily improving; about 70 percent of recipients survive for five years or more. Improvements in survival rates are attributable to improved methods of preserving donor livers, the advent of living donor transplantation, better methods to prevent graft rejection, more suitable selection of recipients (for example, hepatic cancer patients typically have a high rate of recurrence of the disease in their transplanted liver), and improved surgical techniques.
Future prospects include further improvements in surgical techniques and advanced drug therapy to prevent graft rejection but not totally compromise the disease-fighting ability of the patient’s immune system. Efforts at public education regarding the need for donor organs may cause more individuals to contact donor organ societies, family, and friends regarding their wishes to donate organs in the event of untimely death. In addition, improved treatments for the diseases that lead to liver failure may help to decrease the need for this surgical procedure.
Bibliography
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Haerens, Margaret. Organ Donation. Detroit: Greenhaven Press, 2013.
Mulholland, Michael W., et al., eds. Greenfield’s Surgery: Scientific Principles and Practice. 5th ed. Philadelphia: Lippincott Williams & Wilkins, 2011.
National Digestive Diseases Information Clearinghouse. “What I Need to Know About Liver Transplantation.” US Department of Health and Human Services, May 10, 2012.
United Network for Organ Sharing. http://www.unos .org.
Youngson, Robert M. The Surgery Book: An Illustrated Guide to Seventy-three of the Most Common Operations. New York: St. Martin’s Press, 1997.
Zaman, Atif. Managing the Complications of Cirrhosis: A Practical Approach. Thorofare, N.J.: SLACK, 2012.
Zollinger, Robert M., Jr., and Robert M. Zollinger, Sr. Zollinger’s Atlas of Surgical Operations. 9th ed. New York: McGraw-Hill, 2011.
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