Transplantation of a liver

Description:

It is one of the most difficult and long operations, nevertheless it began to be applied often in the special centers of organ transplantation.

The indication to liver transplantation is the end-stage of development of the cirrhosis caused by unlimited alcohol intake, hepatitis C or B, autoimmune hepatitis. Often the indication to operation is primary cholestatic disease of a liver, a fulminantny liver failure, an atresia of bilious ways. Much less often transplantation of a liver is made at benign and malignant tumors, at children - at an atresia of bilious ways and some metabolic diseases

Choice of the recipient. Success of transplantation of a liver depends on the correct choice of the recipient. The main thing is state of his health by the time of change, ability to undergo a heavy operation. The recipient should not have other serious illness in a final phase of their development. In 6 months prior to operation of the patient should not take alcohol and drugs. Operation is not shown in the presence of an extrahepatic oncological disease and the infection which is not giving in to treatment.

The candidate for liver transplantation has to be carefully inspected by specialists of different fields of medicine, including the psychiatrist. Before operation it is necessary to carry out treatment of the available diseases which can affect success of transplantation.

Choice of the donor. The replaced liver has to perform the synthetic function immediately. Otherwise there will come death in the closest 72 h as for maintenance of its function there are no devices, similar to an artificial kidney. The liver, nonfunctioning after transplantation, is deleted and make repeated change. Only the healthy liver of the donor is capable to perform the function right after change. The liver needs to be taken from the donor with brain death and normally functioning heart. The transplant has to correspond or be by the sizes a little less liver of the recipient. At the considerable size of a liver of the donor preference is given to change of the left share (2, 3, sometimes 4 segments) a liver. The transplant is considered of little use if at a biopsy comes to light that 40% and more parenchyma of a liver are replaced with fat. Compatibility tests of bodies of the donor and the recipient at transplantation of a liver differ from those tests which carry usually out at renal transplantation and hearts.

The compatibility test on HLA antigens has no that value, as at renal transplantation, hearts, a pancreas. HLA antigens have physiological property to present virus peptides to T lymphocytes to start process of destruction of the cells infected with a virus. Thus, HLA compatibility will exponentiate an inflammation in the presence at the recipient of a viral infection or autoimmune process, to increase chance of a recurrence of the specified diseases. Do not make also cross cytolytic matching with lymphocytes for forecasting of a possibility of development of superacute reaction of rejection as correlation between results of cross matching and reaction of rejection of a liver minimum. At the same time the superacute reaction of rejection is occasionally observed even at detection at the recipient of preformirovanny antibodies against HLA of donor fabrics and lack of compatibility on AB0-antigens. The compatibility test on AVO-antigens is carried out usually at planned transplantation, In case of emergency sometimes replace even a liver, incompatible on AVO-antigens.

Five-year survival of patients after such change is 15% worse, than at change of AVO of compatible bodies. It is noted also that the replaced liver from the female donor to the man begets worse than a male donor liver.

Acute rejection as well as at change of other bodies, it is carried out about the help of composite reaction of destruction of a liver with the participation of T lymphocytes. Without immunosuppression it is impossible to avoid such reaction. For T lymphocytes primary target for recognition of HLA antigens are the antigens located on a surface of cells of bilious channels and an endothelium of vessels. The acute reaction of rejection of a liver is similar to that after renal transplantation and heart. It arises in 6 months, but often develops during 4 weeks after change. Symptoms of rejection are not specific. They are shown by weakness, temperature increase, deterioration in functional hepatic tests - increase in blood of bilirubin, an alkaline phosphatase, transaminases, clinical symptoms of a liver failure. The diagnosis is confirmed by means of a liver biopsy.

Chronic rejection happens during the period from several months to several years. Immunosuppressive therapy is carried out by the general rules, selecting drugs of various mechanism of action. There are several schemes (protocols) of immunosuppression that allows to choose the most suitable of them. The transplantations of a liver of a complication arising later divide into 4 severity. For treatment of each of them the corresponding scheme of treatment is provided.

Survival after operation makes 90%. Survival within one year is equal to 73%, within 5 years about 60%. Recipients need constant observation and control.

Apply generally orthotopical, the trance - plantations is more rare heterotopic (see fig. 28.3). At orthotopical transplantation the liver of the recipient is deleted, and replace an allogenic liver of the donor to its place. At the same time connect the allocated blood vessels of a liver of the donor to the lower vena cava, a portal vein and a hepatic artery of the recipient.

Zhelchny Canal of a donor liver is connected an anastomosis to the loop of a jejunum of the recipient which is switched off across Ru. At heterotopic transplantation the liver of the recipient is not deleted.

As removal of several segments of the left hepatic lobe became safe, some centers give preference to change of the left share (2-3, sometimes 4 segments) a liver from the living related donor, connecting vessels of the transplanted part of a liver to vessels of a spleen of the recipient, and a bilious channel - to the jejunum loop which is switched off across Ru. This intervention is less difficult, gives excellent engraftment of a transplant and excellent functional results owing to the best histocompatability and reduction of time of ischemia of the replaced body. Ethical problems are difficult. For the sake of the child's life mother will often run risks for own health. Due to the improvement of immunodepressive therapy many specialists consider capture of the left hepatic lobe at the living related donor unjustified risk as the left hepatic lobe of the donor with brain death can yield so good net results.