Problems of modern transplantation. Actual problems of transplantation
The problem of shortage of organs for transplantation is urgent for all mankind as a whole. About 18 people die every day due to the lack of organ and soft tissue donors, without waiting for their turn. Organ transplantation in the modern world is mostly performed from deceased people who, during their lifetime, signed the relevant documents on their consent to donation after death.
What is a transplant
Organ transplantation is the removal of organs or soft tissues from a donor and their transfer to a recipient. The main direction of transplantology is organ transplantation - that is, those organs without which existence is impossible. These organs include the heart, kidneys, and lungs. While other organs, such as the pancreas, can be replaced by replacement therapy. To date, great hopes for prolonging human life are given by organ transplantation. Transplantation is already successfully practiced. These are kidneys, liver, thyroid gland, cornea, spleen, lungs, blood vessels, skin, cartilage and bones to create a framework in order to form new tissues in the future. For the first time, kidney transplant surgery to eliminate acute kidney failure patient was carried out in 1954, the donor was an identical twin. Organ transplantation in Russia was first performed by Academician Petrovsky B.V. in 1965.
What are the types of transplants
All over the world there are a huge number of terminally ill people who need a transplant. internal organs and soft tissues, since traditional methods of treating the liver, kidneys, lungs, and heart provide only temporary relief, but do not fundamentally change the patient's condition. There are four types of organ transplants. The first of them - allotransplantation - takes place when the donor and recipient belong to the same species, and the second type includes xenotransplantation - both subjects belong to different species. In the case when tissue or organ transplantation is performed in or animals grown as a result of consanguineous crossing, the operation is called isotransplantation. In the first two cases, the recipient may experience tissue rejection, which is caused by the body's immune defense against foreign cells. And in related individuals, tissues usually take root better. The fourth type includes autotransplantation - transplantation of tissues and organs within the same organism.
Indications
As practice shows, the success of the operations performed is largely due to the timely diagnosis and accurate determination of the presence of contraindications, as well as how timely the organ transplant was performed. Transplantation should be predicted taking into account the patient's condition both before and after the operation. The main indication for the operation is the presence of incurable defects, diseases and pathologies that cannot be treated with therapeutic and surgical methods, as well as threatening the life of the patient. When performing transplantation in children, the most important aspect is to determine the optimal moment for the operation. As experts of such an institution as the Institute of Transplantology testify, postponing the operation should not be carried out for an unreasonably long period, since a delay in the development of a young organism may become irreversible. Transplantation is indicated in case of a positive life prognosis after surgery, depending on the form of pathology.
Organ and tissue transplantation
In transplantology most widespread received autotransplantation, as it excludes tissue incompatibility and rejection. Most often, operations are performed on adipose and muscle tissues, cartilage, bone fragments, nerves, and the pericardium. Transplantation of veins and vessels is widespread. This became possible thanks to the development of modern microsurgery and equipment for these purposes. A great achievement of transplantation is the transplantation of fingers from the foot to the hand. Autotransplantation also includes the transfusion of one's own blood in case of large blood loss during surgical interventions. With allotransplantation, bone marrow and blood vessels are most often transplanted. This group includes blood transfusion from relatives. Operations are carried out very rarely, since so far this operation is faced with great difficulties, however, in animals, transplantation of individual segments is successfully practiced. Pancreas transplantation can stop the development of such serious illness like diabetes. IN last years 7-8 out of 10 operations performed are successful. In this case, not the entire organ is transplanted, but only part of it - islet cells that produce insulin.
Law on organ transplantation in the Russian Federation
On the territory of our country, the transplantation industry is regulated by the Law of the Russian Federation of December 22, 1992 “On transplantation of human organs and (or) tissues”. In Russia, transplantation of the kidneys is most often performed, less often of the heart, liver. The law on organ transplantation considers this aspect as a way to preserve the life and health of a citizen. At the same time, the legislation considers the preservation of the life of the donor as a priority in relation to the health of the recipient. According to the Federal Law on organ transplantation, the objects can be the heart, lung, kidney, liver and other internal organs and tissues. Organ retrieval can be carried out both from a living person and from a deceased person. Organ transplantation is carried out only with the written consent of the recipient. Donors can only be capable persons who have passed medical examination. Organ transplantation in Russia is carried out free of charge, since the sale of organs is prohibited by law.
Donors for transplantation
According to the Institute of Transplantation, each person can become a donor for organ transplantation. For persons under the age of eighteen, parental consent is required for the operation. When signing the consent for organ donation after death, a diagnosis and medical examination are carried out, which allows you to determine which organs can be transplanted. Carriers of HIV, diabetes mellitus, cancer, kidney disease, heart disease and other serious pathologies are excluded from the list of donors for organ and tissue transplantation. Related transplantation is performed, as a rule, for paired organs - kidneys, lungs, as well as unpaired organs - liver, intestines, pancreas.
Contraindications for transplantation
Organ transplantation has a number of contraindications due to the presence of diseases that can be aggravated as a result of the operation and pose a threat to the patient's life, including death. All contraindications are divided into two groups: absolute and relative. The absolute ones are:
- infectious diseases in other organs along with those that are planned to be replaced, including the presence of tuberculosis, AIDS;
- dysfunction of vital important organs, damage to the central nervous system;
- cancerous tumors;
- malformations and birth defects incompatible with life.
However, during the period of preparation for the operation, due to the treatment and elimination of symptoms, many absolute contraindications become relative.
kidney transplant
Kidney transplantation is of particular importance in medicine. Since this is a paired organ, when it is removed from the donor, there are no violations of the body that threaten his life. Due to the peculiarities of the blood supply, the transplanted kidney takes root well in recipients. For the first time, experiments on kidney transplantation were carried out in animals in 1902 by research scientist E. Ulman. During transplantation, the recipient, even in the absence of supporting procedures to prevent rejection of a foreign organ, lived for a little more than six months. Initially, the kidney was transplanted to the thigh, but later, with the development of surgery, operations began to be performed to transplant it into the pelvic area, this technique is practiced to this day. The first kidney transplant was performed in 1954 between identical twins. Then, in 1959, an experiment was carried out on kidney transplantation in fraternal twins, using a technique to resist transplant rejection, and it proved to be effective in practice. New drugs have been identified that can block the body's natural mechanisms, including the discovery of azathioprine, which suppresses the body's immune defenses. Since then, immunosuppressants have been widely used in transplantology.
Organ conservation
Any vital organ that is intended for transplantation, without blood supply and oxygen, is subject to irreversible changes, after which it is considered unsuitable for transplantation. For all organs, this period is calculated differently - for the heart, time is measured in minutes, for the kidney - several hours. Therefore, the main task of transplantation is to preserve organs and maintain their performance up to transplantation into another organism. To solve this problem, conservation is used, which consists in supplying the organ with oxygen and cooling. The kidney can be preserved in this way for several days. The preservation of the organ allows you to increase the time for its study and selection of recipients.
Each of the organs after receiving it must be subjected to conservation, for this it is placed in a container with sterile ice, after which conservation is carried out with a special solution at a temperature of plus 40 degrees Celsius. Most often, a solution called Custodiol is used for these purposes. Perfusion is considered completed if a pure preservative solution without blood impurities protrudes from the orifices of the graft veins. After that, the organ is placed in a preservative solution, where it is left until the operation is performed.
transplant rejection
When a graft is transplanted into the recipient's body, it becomes the object of the body's immunological response. As a result of the protective reaction of the recipient's immune system, a number of processes occur at the cellular level, which lead to the rejection of the transplanted organ. These processes are explained by the production of donor-specific antibodies, as well as antigens of the recipient's immune system. There are two types of rejection - humoral and hyperacute. In acute forms, both mechanisms of rejection develop.
Rehabilitation and immunosuppressive treatment
To prevent this side effect, immunosuppressive treatment is prescribed depending on the type of operation performed, blood type, the degree of compatibility of the donor and recipient, and the patient's condition. The least rejection is observed in related organ and tissue transplantation, since in this case, as a rule, 3-4 out of 6 antigens coincide. Therefore, a lower dose of immunosuppressants is required. Liver transplantation demonstrates the best survival rate. Practice shows that the organ demonstrates more than a decade of survival after surgery in 70% of patients. With prolonged interaction between the recipient and the graft, microchimerism occurs, which allows, over time, to gradually reduce the dose of immunosuppressants up to complete failure from them.
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Introduction
1.1 Historical aspects of the development of transplantology as a science
2.4 Possible Solutions donor organ shortage problems
2.5 Problems of transplantology in the religious aspect
Conclusion
Bibliography
Introduction
The relevance of research. Transplantation (transplantation) of human organs and (or) tissues is a means of saving lives and restoring people's health.
Transplantology is a branch of medicine that studies the problems of transplantation of organs and tissues, such as kidneys, liver, heart, bone marrow, etc., as well as the prospects for creating artificial organs.
Every year, 100,000 organ transplants and more than 200,000 human tissues and cells are performed in the world. Of these, up to 26 thousand account for kidney transplantation, 8-10 thousand - liver, 2.7-4.5 thousand - heart, 1.5 thousand - lungs, 1 thousand - pancreas. The United States is the leader among the countries of the world in terms of the number of transplants: annually, American doctors perform 10,000 kidney transplants, 4,000 liver transplants, and 2,000 heart transplants. In Russia, 4-5 heart transplants, 5-10 liver transplants, 500-800 kidney transplants are performed annually. This figure is hundreds of times lower than the need for these operations.
Nowadays, the topic of organ and tissue transplantation is very relevant, as it affects moral and ethical, as well as economic problems.
The purpose of the course study. Consider the main issues of organ and tissue transplantation, such as legislative, moral and ethical. Also, the paper will consider the historical aspects of the emergence of transplantology as a science and the prospects for its development.
Research objectives:
1. Describe the historical aspects of the development of transplantology as a science.
2. Consider the features of the procedure for organ and tissue transplantation.
3. To study the main problems of organ and tissue transplantation, such as: the problem of organ harvesting, ascertaining the death of a person, the distribution of donor organs, the shortage of donor organs, as well as the problem of transplantation from the point of view of religion.
Object of study: transplantation of organs and tissues in the modern era.
Subject of study: the contribution of scientists from different countries to the development of science, the donor-recipient, the human immune system, the use of immunosuppressive therapy, types of transplants.
Research methods: theoretical analysis, synthesis of the received data.
Chapter 1. General information about transplantology
This chapter will discuss issues related to the history of the emergence of transplantation, the contribution of domestic and foreign scientists to the development of this science, as well as basic information about the process of organ and tissue transplantation.
1.1 Historical aspects of the emergence of transplantology as a science
The idea to replace parts of the body that have become unusable, like parts in a mechanism, arose a very long time ago. According to the apocrypha, in the 3rd century, Saints Cosmas and Damian successfully transplanted the leg of a recently deceased Ethiopian into their patient. True, they were assisted by angels. The topic of transplantation also fascinated writers: Professor Preobrazhensky transplanted endocrine glands, Dr. Moreau sewed animal heads on his patients, and Professor Dowell - the heads of corpses.
At the beginning of the last century, a donor cornea was successfully transplanted to a person for the first time. However, the spread of other organ transplants has been hampered by a lack of knowledge about immunity. An organism rejects a transplanted organ if it is not from a genetically identical organism. The Bologna Renaissance surgeon Gaspar Tagliacozzi (1545-1599), who successfully performed autologous skin transplants, noted back in 1597 that when a fragment of someone else's skin is transplanted to a person, rejection always occurs.
Only by the middle of the 20th century, scientists discovered the mechanisms of immune reactions and learned how to suppress them so that the donor organ would normally take root. Despite this, forced suppression of the immune response remains an important problem in transplantation: firstly, after an organ transplant, the recipient becomes vulnerable to infections, and secondly, steroids used to suppress immunity have severe side effects. In recent years, alternative methods of suppressing immunity without the use of steroids or reducing their dose have been developed and applied - for example, scientists at Northwestern University and the University of Wisconsin are working on this issue. Today, transplantation of the skin, kidney, liver, heart, intestines, lungs, pancreas, bones, joints, veins, heart valves, cornea is well mastered. In 1998, the hand was successfully transplanted for the first time. Recent achievements include the first face transplant in France in 2005 and a penis transplant in China in 2006. The world leader in transplants is the United States: per million inhabitants, 52 kidney transplants, 19 liver transplants, 8 heart transplants are performed annually.
The history of organ transplantation goes far into the past: for example, back in 1670 Macren tried to transplant a dog's bone into a human, in 1896 Guard proposed the terms auto-, homo-, re- and heterotransplantation. Currently, these terms have changed and the transplantation of one's own tissues is called replantation or autotransplantation, the transplantation of tissues and organs within the same species is allotransplantation, and the transplantation of tissues and organs between different species is xenotransplantation.
In 1912, the French surgeon Alex Carrel proposed the use of a donor arterial patch in organ transplants and was awarded Nobel Prize for experimental work in the field of transplantation. In 1923, the Russian scientist Elansky performed a skin transplant taking into account the blood type.
The modern era of transplantation began in the 1950s, but the groundwork for this was laid earlier. So in 1943-1944. at Oxford, Peter Medwar and colleagues came to the conclusion that the rejection reaction is a manifestation of actively acquired immunity. For a set of works on the study of the reaction of rejection and neonatal tolerance in transplantation of organs and tissues, he was awarded the Nobel Prize.
February 23, 1946 at the Balashikha Fur Institute, Vladimir Petrovich Demikhov performed the first experimental transplantation additional heart. In the USA, surgeon Welch began to perform regular experiments on liver transplantation in dogs only in 1955. On December 23, 1954, in Boston (USA) by plastic surgeon Joseph Murray ( Nobel Laureate 1991) performed the world's first successful related kidney transplant from a homozygous twin.
On March 1, 1963, American surgeon Thomas Starzl performed the world's first human liver transplant in Denver. A second liver transplant was performed in May 1963 and the patient lived for 3 weeks.
important event for the subsequent progress in organ transplantation was the legalization in London in 1966 of the concept of brain death. In 1968, the criteria for brain death were clearly defined at Harvard Medical School, and in 1976 they were published in London. Since 1970, organ harvesting from brain dead donors has become a routine procedure in most countries of the world.
December 3, 1967 in Cape Town, Christian Bernard performed a heart transplant. The recipient was a 54-year-old man with coronary heart disease and post-infarction aneurysm of the left ventricle, the donor was a 25-year-old woman who died as a result of a traumatic brain injury.
In 1968, Denton Coley performed the world's first cardiopulmonary transplant in Houston, but the patient died 24 hours after the operation. The first successful lung transplantation in a patient with silicosis was performed in Ghent by the Belgian surgeon Fritz Der in 1968.
The patient lived for 10 months.
Further progress in organ transplantation was associated with the discovery in 1976 of cyclosporine A, a drug with selective immunosuppressive activity.
Despite the historical leadership in clinical and experimental transplantation, this branch of medicine began to develop in Russia only in the mid-1960s. In 1965 B.V. Petrovsky performed the first successful kidney transplant from a related donor.
Currently, organ and tissue transplantation, as well as organ donation in Russia, is regulated by the law of the Russian Federation "On transplantation of human organs and (or) tissues" of 1992.
Looking through the chronology of the development of transplantology, it is clear that scientists have long tried to use organ transplantation as a way to prolong human life, the possibility of high-quality and full life human in connection with the replacement of organs that have lost their function. But along the way, various problems arose that remain relevant to this day. For example, the search for a donor, the distribution of donor material between recipients, the commercialization of the issue, as well as the ethical side of the issue. Nevertheless, transplantation as a science continues to develop and improve.
1.2 Features of the procedure for organ and tissue transplantation
Organ transplantation (transplantation) is the removal of a viable organ from one individual (donor) with its transfer to another (recipient). If the donor and recipient belong to the same species, they speak of allotransplantation; if different - about xenotransplantation. In cases where the donor and the patient are identical (identical) twins or representatives of the same inbred (i.e., obtained as a result of consanguineous crossing) line of animals, we are talking about isotransplantation.
Xeno- and allografts, unlike isografts, are rejected. The rejection mechanism is undoubtedly immunological, similar to the body's reaction to the introduction of foreign bodies. Isografts taken from genetically related individuals are usually not rejected.
In experiments on animals, almost all vital organs have been transplanted, but not always with success. Vital organs - those without which the preservation of life is almost impossible. Examples of such organs are the heart and kidneys. However, a number of organs, say the pancreas and adrenal glands, are usually not considered vital, since the loss of their function can be compensated. replacement therapy, in particular the introduction of insulin or steroid hormones.
Kidneys, liver, heart, lungs, pancreas, thyroid and parathyroid gland, cornea and spleen. Some organs and tissues, such as blood vessels, skin, cartilage, or bone, are transplanted to create a scaffold on which new recipient tissues can form.
The organ transplant procedure is always associated with the removal of donor organs and tissues, either from living or deceased donors.
Organ removal for transplantation from a living donor is often practiced in kidney transplants; For normal functioning the urinary system is quite enough of the remaining kidney.
The consent of a close relative of the patient to become a donor radically reduces the risk of transplant rejection. The closest relatives of the recipient - parents, sisters or brothers - are genetically close to him; therefore, the probability of recognition of the transplant recipient's immune system as foreign is reduced. In addition, in this case, there is no need for the rush that is inevitable when transplanting organs taken from a dead donor, which allows for more thorough preparation and planning of the operation.
In transplantology, there is such a thing as organ conservation.
In any vital organ intended for transplantation, if it is deprived of blood and oxygen for a long time, irreversible changes occur that do not allow it to be used. For the heart, this period is measured in minutes, for the kidney - in hours. The development of ways to preserve these organs after their removal from the body of the donor spend huge effort. Limited but encouraging success has been achieved by cooling organs, supplying them with pressurized oxygen, or perfusing them with chilled tissue-preserving buffers. A kidney, for example, can be stored under such conditions outside the body for several days. Organ preservation increases the time available for selection of a recipient through compatibility testing and ensures the suitability of the organ. Within the framework of currently existing regional, national and even international programs, cadaveric organs are harvested and distributed, which allows them to be optimally used.
The main problem of transplant surgery and the cause of most of the complications directly or indirectly caused by organ transplantation is graft rejection. The powerful immune system of the body protects it from invading pathogenic bacteria and viruses. Foreign bodies that have entered the body are recognized by the immune system by their chemical structure, which is not characteristic of the body. Unfortunately, when the transplanted organ comes into contact with the cells of the immune system, they begin to fight the graft as if it were a source of infection.
That is why, before proceeding with an organ transplant operation, the closest attention is paid to assessing the compatibility of the tissues of the donor organ with the tissues of the recipient's body. The procedure is similar to the definition of a blood group; human tissues also belong to different types. Tissue typing is carried out by examining white blood cells; blood groups are established by more numerous erythrocytes.
In addition to checking whether the donor's blood type matches the tissue type, there are many ways to prevent rejection. It has been established, for example, that the more often a recipient has undergone a blood transfusion, the less likely the risk of rejection is.
The essence of the preventive effect lies in the fact that the immune system, which repeatedly resisted foreign erythrocytes of donor blood, became more tolerant in them, which explains the reduced risk of transplant rejection.
The purposeful prevention of rejection consists in the appointment of powerful immunosuppressants - drugs that suppress the immune system and, thus, reduce the body's resistance to foreign organisms and cells. The use of immunosuppressants is a double-edged sword, because the body, gaining tolerance to a donor organ, loses its full-fledged immune protection against bacterial, viral and fungal infections. Therefore, when caring for patients taking drugs in this group, all measures must be taken to prevent infection and early detection infectious diseases, special attention require rare infections.
An organ transplant requires a healthy donor organ. The fact that two kidneys are given to humans by nature makes it possible to transplant approximately one third of recipients with a kidney from a living donor. Other transplants require a cadaveric organ. The scarcity of cadaveric organs severely limits organ and tissue transplantation, as only brain-dead (with a beating heart) donors are acceptable, and only about 1% of dying patients meet existing donor selection criteria.
Cadaveric organ donors are formerly healthy people who suffered irreversible brain damage as a result of the disaster. The presence of a history of injury or disease of the organ considered in terms of transplantation excludes the latter. All oncological diseases, with the exception of a primary brain tumor, automatically exclude the patient as a possible donor. An untreated systemic bacterial, fungal, or viral infection is also a contraindication to donation. However, donors with adequately treated infections may be suitable. Prolonged ischemia caused by profound hypotension or cardiac arrest can make certain bodies unacceptable for transplantation. Patients with a long history of hypertension, diabetes mellitus and cardiovascular disease should be examined more carefully. The age of the patient is a relative contraindication. In the absence of perfect criteria, the purpose of the donor survey is to identify those donors whose functional organs can be transplanted and excluded from further consideration those whose organs are not expected to function adequately. Due to ever-increasing demand, the acceptance limits for organs are constantly being reviewed. Different organs are affected differently by age and disease. Therefore, when evaluating a donor, organ-specific criteria are used.
Thus, in the process of development and improvement of transplantology as a science, as well as new scientific discoveries, the organ transplant operation has become safer and more predictable. Many thousands of patients have hope for recovery. Despite this, transplant doctors each time face many other problems, such as ethics, the force of laws, etc.
Chapter 2. Problems of organ and tissue transplantation in the modern era
transplantology organ death donor
Despite the need for organ transplant operations, transplantology constantly faces a number of problems related to life and health, as well as the moral principles of a person. The next chapter will look at the main problems that doctors and patients have to deal with.
2.1 The problem of organ and tissue harvesting
Ethical and legal issues of transplantation relate to the justification and unjustification of transplantation of vital organs in the clinic, as well as the problems of taking organs from living people and corpses. Organ transplantation is often associated with big risk for the lives of patients, many of the relevant operations are still in the category of medical experiments and have not been included in clinical practice.
Organ transplantation from a living donor is associated with harm to his health. In transplantology, the observance of the ethical principle “do no harm” in cases where the donor is a living person turns out to be practically impossible. The doctor faces a contradiction between the moral principles "do no harm" and "do good". On the one hand, an organ transplant (for example, a kidney) is saving a person's life, i.e. is a blessing to him. On the other hand, the health of a living donor this body significant harm is caused, i.e. the principle of "do no harm" is violated, evil is done. Therefore, in cases of living donation, it is always about the degree of benefit received and the degree of harm caused.
Under Russian law, only a relative of the recipient can act as a living donor, and a prerequisite for both the donor and the recipient is voluntary informed consent for transplantation.
The most common type of donation at present is the removal of organs and (or) tissues from a dead person. This type donation is associated with a number of ethical, legal and religious problems, among which the most important are: the problem of ascertaining the death of a person, the problem of voluntary expression of will to donate one's own organs after death for transplantation, the admissibility of using the human body as a source of organs and tissues for transplantation from the standpoint of religion. Solutions to these problems are reflected in a number of ethical and legal documents of the international, national and confessional levels.
The motto of modern transplantology is: “When you leave this life, do not take your organs with you. We need them here." However, during life, people rarely leave orders for the use of their organs for transplantation after their death. This is due, on the one hand, to the legal norms for the collection of donor organs in force in a particular country, and on the other hand, to subjective reasons of an ethical, religious, moral and psychological nature.
Currently, there are three main types of organ harvesting from a corpse in the world in the field of human organ and tissue donation: routine harvesting, harvesting in accordance with the principle of presumption of consent, and harvesting in accordance with the principle of presumption of disagreement of a person to the removal of organs from his body after his death.
Routine organ harvesting is based on the recognition of the body after the death of a person as the property of the state and therefore it can be used for research purposes, for the collection of organs and tissues and other purposes in accordance with the needs of the state. This type of attitude towards the human body and the type of organ and tissue sampling for subsequent transplantation took place in our country until 1992. Currently, in the world, organ harvesting from a corpse is carried out in accordance with the principles of presumption of consent or presumption of disagreement.
The principle of presumption of consent is the recognition of a person's initial consent to any action. If a person does not agree to the commission of the proposed actions, then he must express his disagreement in the prescribed form.
Removal of organs and tissues from a corpse is not allowed if, at the time of removal, the health care institution is aware that during his lifetime this person, or his close relatives or legal representative, declared their disagreement with the removal of his organs or tissues after death for transplantation to the recipient. Thus, this principle allows the taking of tissues and organs from a corpse, if the deceased person, or his relatives, did not express their disagreement with this.
The principle of presumption of disagreement is the recognition of a person's initial disagreement with any action. If a person agrees to the commission of the proposed actions, then he must express his consent in the prescribed form.
Obtaining the consent of a person or his relatives for the use of his organs for transplantation is associated with a number of ethical and psychological problems. Obtaining consent from a person in a terminal state is almost impossible for both ethical and medical reasons. a person, as a rule, is physically in such a state when he cannot make voluntary, responsible decisions on the basis of complete and reliable information provided to him in accessible form. Communication with relatives of a dying or just deceased person is also an extremely complex and responsible ethical and psychological task.
2.2 The problem of ascertaining the death of a person
When collecting donor organs from a corpse, the first problem that arises is establishing the moment of possible organ harvesting.
The problem of ascertaining the death of a person at the end of the 20th century. has moved from the category of purely medical problems to the category of bioethical ones in connection with the development of resuscitation, transplantation and other technologies in medicine. Depending on what state human body is recognized as the moment of his death as a person, it becomes possible to stop maintenance therapy, take measures to remove organs and tissues for their further transplantation, etc.
In the vast majority of countries of the world, brain death is recognized as the main criterion for human death. The concept of brain death was developed in neurology after the description of the state of transcendental coma by the French neuropathologists P. Molar and M. Goulon. This concept is based on the understanding of human death as a state of irreversible destruction and (or) dysfunction of critical body systems, i.e. systems that are irreplaceable by artificial, biological, chemical or electronic-technical systems, and such a system is only the human brain. Currently, the concept of "brain death" means the death of the entire brain, including its stem, with an irreversible unconscious state, the cessation of spontaneous breathing and the disappearance of all stem reflexes.
In our country, the fact of death of a person is established by a number of signs in accordance with the Order of the Ministry of Health of the Russian Federation No. 73 dated March 4, 2003 and the instruction of the Ministry of Health of the Russian Federation on ascertaining the death of a person based on the diagnosis of brain death. The order says: “Brain death is manifested by the development of irreversible changes in the brain, and in other organs and tissues, partially or completely, biological death is expressed by post-mortem changes in all organs and systems that are permanent, irreversible, cadaveric character". The instruction defines: “Brain death is a complete and irreversible cessation of all brain functions, recorded with a beating heart and artificial lung ventilation. Brain death is equivalent to the death of a person” (p. 1). The diagnosis of "brain death" is established on the basis of a whole range of signs (clinical tests) indicated in this instruction.
The history of domestic transplantology has already included the “case of transplant doctors”, which to this day causes discussion, has no final decision (court decisions have been reviewed several times) and, therefore, has a negative impact on the practice of organ transplantation. The situation that has become a “case” is quite typical for healthcare practice: a patient with a diagnosis of “traumatic brain injury” is admitted to the hospital by “ambulance” and his condition is characterized as incompatible with life. In a hospital setting, the patient has three cardiac arrests. After the third cardiac arrest, resuscitation measures are ineffective, and a decision is made to remove a kidney from him for transplantation. The actions of medical workers were interrupted by representatives of law enforcement agencies, the patient died.
An analysis of this situation from the standpoint of biomedical ethics shows, first of all, the moral vulnerability of the criterion of "brain death" as the death of a person and the need for a very responsible attitude to the execution of each item of any instruction, no matter how insignificant, "bureaucratic" it may seem.
2.3 The problem of organ allocation
It is relevant all over the world and exists as a problem of shortage of donor organs. The distribution of donor organs in accordance with the principle of fairness is decided by including recipients in a transplant program based on the practice of "waiting lists". "Waiting lists" are lists of patients who need a transplant of a particular organ, indicating the characteristics of their state of health. The problem is that a patient, even in a very serious condition, can be in the first place on this list and never wait for a life-saving operation for him. This is due to the fact that it is very difficult to select an organ suitable for a given patient from the available volume of donor organs due to immunological incompatibility. This problem is to some extent solved by improving the methods of immunosuppressive therapy, but still remains very relevant.
So, the main criterion influencing the doctor's decision is the degree of immunological compatibility of the donor-recipient pair. In accordance with it, the organ is not given to the one who has a higher or lower position, not to the one who has a higher or lower income, but to the one to whom it is more suitable for immunological indicators. This approach is similar to how a blood transfusion is performed.
The immunological and biological data of a person in need of an organ transplant are entered into a database. Waiting lists exist at different levels, for example, in large cities such as Moscow, at the level of oblasts, regions, and even at the national level.
On the other hand, there is a database of donor organs and their immunological parameters. When a donor organ appears, its biological data begin to be compared with the biological parameters of people on the waiting list. And with whose parameters the organ is compatible, they give it to him. This principle of distribution is considered the most fair and is fully justified from a medical point of view, because. helps to reduce the likelihood of rejection of this organ.
But what if the donor organ suits several recipients from the list? In this case, the second criterion comes into play - the criterion of the degree of severity of the recipient. The condition of one recipient allows you to wait another six months or a year, and the other no more than a week or a month. The organ is given to the one who can wait the least. This usually ends the distribution.
In a situation where the organ is almost equally suitable for two recipients, and they are both in critical condition and cannot wait long, the decision is made on the basis of the first-come-first-served criterion. The physician must take into account the duration of the recipient's stay on the waiting list. Preference is given to those who are on the waiting list first.
In addition to the three criteria mentioned above, the distance, or rather the remoteness of the recipient from the location of the donor organ, is also taken into account. The fact is that the time between the removal of an organ and its transplantation is strictly limited, the organ with the shortest time for transplantation is the heart, about five hours. And if the time spent on overcoming the distance between the organ and the recipient is longer than the “life” of the organ, then the donor organ is given to a recipient located at a closer distance. So, the main criteria for the distribution of donor organs in terms of their importance: the first, main - the degree of immunological compatibility of the donor-recipient pair, the second - the degree of severity of the recipient and the third - priority.
2.4 Tackling the organ shortage
The problem of shortage of donor organs is being solved in ways: there is propaganda of organ donation after the death of a person with a lifetime consent to this, artificial organs are being created, methods are being developed for obtaining donor organs from animals by cultivating somatic stem cells with the subsequent obtaining of certain types of tissues, creating artificial organs based on achievements of bioelectronics and nanotechnologies.
The creation and use of artificial organs is the first direction in transplantology, in which the problem of organ shortage and other problems associated with organ harvesting from a person, both living and dead, began to be solved. IN medical practice widely used apparatus artificial kidney”, artificial heart valves have entered the practice of cardiotransplantology, an artificial heart is being improved, artificial joints and eye lenses are being used. This is a path that depends on the latest achievements in the field of other sciences (technical, chemical and biological, etc.), requiring significant economic costs, scientific research and testing.
Xenotransplantation is currently one of the ways to solve the problem of shortage of donor organs. The idea of using animals as donors is based on the belief that an animal is a less valuable living organism than a human being. This is objected to by both supporters of animal welfare and representatives of transhumanism, who believe that every living being has the right to life and it is inhumane to kill another for the sake of continuing the life of one living being. At the same time, people have been killing animals for thousands of years to satisfy their needs for food, clothing, etc. .
The greatest problems arise in the field of solving scientific and medical problems associated with the danger of transfer into the human body various infections, viruses and immunological incompatibility of animal organs and tissues with the human body. In recent years, pigs have come to the fore as donors for xenotransplantation, which have the closest set of chromosomes to humans, the structure of internal organs, rapidly and actively reproduce, and have long been domestic animals. Successes in the field genetic engineering made it possible to obtain a variety of transgenic pigs that have a human gene in their genome, which should reduce the likelihood of immunological rejection of organs transplanted from a pig to a human.
A significant ethical and psychological problem is the acceptance by a person of an animal organ as his own, the awareness of his body as a holistic, truly human even after transplanting any animal organ into it.
Therapeutic cloning of organs and tissues is the possibility of creating donor organs based on the use of genetic technologies. Human stem cell research has opened up prospects for medicine to obtain donor organs and tissues through the cultivation of somatic stem cells. Experiments are currently underway to obtain artificial conditions cartilage, muscle and other tissues. The path is very attractive from an ethical point of view, since it does not require the invasion of any organism (living or dead) in order to take organs from it. Scientists see great prospects for this way of obtaining donor organs and tissues of the human body, since opportunities open up not only for obtaining the organs and tissues themselves, but also for solving the problem of their immunological compatibility, because the starting material is the somatic cells of the person himself. Thus, the person himself becomes both a donor and a recipient, which removes many ethical and legal problems of transplantation. But this is a path of experimentation and scientific research, which, although yielding some encouraging results, is still far from being implemented in public health practice. These are the technologies of the future, because they are based on the use of stem cell culture technologies necessary for a person fabrics, which is currently a problem that is also at the stage of research and development.
2.5 The problem of transplantology in the religious aspect
The Russian Orthodox Church in "Fundamentals of the Social Concept" noted that modern transplantology makes it possible to provide effective assistance to many patients who were previously doomed to inevitable death or severe disability. At the same time, the development of this field of medicine, increasing the need for the necessary organs, gives rise to certain moral issues and may pose a danger to society. The Church believes that human organs cannot be considered as an object of purchase and sale. An organ transplant from a living donor can only be carried out on the basis of voluntary self-sacrifice in order to save the life of another person. In this case, consent to explantation (removal of an organ) becomes a manifestation of love and compassion. However, the potential donor must be fully informed about possible consequences explantation of an organ for its health. Explantation is morally unacceptable, directly life threatening donor. It is unacceptable to reduce the life of one person, including the refusal of life-sustaining procedures, in order to prolong the life of another. Posthumous organ and tissue donation can be a manifestation of love that extends beyond death. This kind of gift or bequest cannot be considered an obligation of a person. The Church considers the so-called presumption of consent of a potential donor to the removal of organs and tissues of his body, enshrined in the legislation of a number of countries, as an unacceptable violation of human freedom.
Most Western Christian theologians are supporters of transplantation and positively assess the fact of the removal and transfer of the organ of the deceased into the body of a living person. The Roman Catholic Church believes that transplant donation is an act of mercy and a moral duty. The Catholic Charter of Healthcare Professionals defines transplantation as a "service to life" in which "a portion of oneself, one's own blood of the flesh, is offered so that others may continue to live." Catholicism allows organ transplants and blood transfusions if there are no alternative treatments to save the patient's life. Donation is allowed only on a voluntary basis. Protestant theologians recognize the legitimacy of the existence of a person who received an organ from another, however, the sale of organs is considered immoral.
In Judaism, the human body is treated with great respect even after death. The body of the deceased cannot be opened. It is possible to take organs for transplantation only on the condition that the person himself before death allowed this and the family does not object to this. When organ retrieval, special care must be taken to ensure that the donor's body is not mutilated. Orthodox Jews may refuse an organ transplant or blood transfusion unless the procedure is approved by a rabbi. Judaism allows organ transplants when it comes to saving human life.
In Buddhism, organ transplantation is considered possible only from a living donor, provided that it was a gift to the patient.
The Council of the Islamic Academy of Jurisprudence at its 4th session in 1988 adopted Resolution No. 26 (1/4) on the problems of transplantation of organs of a living and deceased person. It states that the transplantation of a human organ from one place of his body to another is permitted if the expected benefit of the operation clearly outweighs the possible harm and if the purpose of the operation is to restore the lost organ, restore its shape or natural function, eliminate its defect or disfigurement that bring physical and moral suffering to a person. An essential condition for transplantation from a living donor is that the transplant has the property of physical regeneration, as in the case of blood or skin, as well as the full capacity of the donor and compliance with all Sharia norms during the operation.
Sharia prohibits the transplantation of vital organs from a living person, as well as organs whose transplantation entails a deterioration in vital functions, although it does not threaten with a fatal outcome. Organ transplantation and blood transfusion is possible only from living donors who profess Islam and have given their consent. Transplantation is allowed from a person with cerebral death, who is artificially supported by breathing and blood circulation.
Organ transplantation from a corpse is allowed, provided that life or one of the vital functions of the body depends on it, and the donor himself during his lifetime or his relatives after death expressed their consent to organ transplantation. In the event that the identity of the deceased cannot be identified or no heirs have been identified, then the authorized head of the Muslims gives consent to transplantation. Thus, the Shariah establishes the principle of the presumption of disagreement.
In Islam, organ transplantation on a commercial basis is strictly prohibited. Organ transplantation is allowed only under the supervision of an authorized specialized institution.
Thus, despite the great prospects in the field of medical care for people, transplantology remains largely an area of scientific research and experimentation. For most medical professionals, the ethical problems of modern transplantology are an example of solving the moral problems that arise in the field of manipulations with the human body, both living and dead. This is an area of thought about the right to dispose of one's body, even after death, about respect for the human body, which is part of its human essence.
Conclusion
Currently, transplantation is one of the areas of practical healthcare. According to the data of the 9th World Congress of Transplantologists (1982), hundreds of hearts (723), tens of thousands of kidneys (64,000), etc. have been transplanted. While transplant surgeries were counted in units and were experimental in nature, they aroused surprise and even approval. 1967 is the year when C. Bernard performed the world's first heart transplant. Behind her, during 1968, another 101 similar operations were performed. These years were called in the press the time of "transplantation euphoria".
There is no doubt that transplantation of organs and tissues of the human body is a significant success. modern medicine. Transplantation at this stage is a complex of medical and biological measures, including the solution of such problems as:
Elimination of biological incompatibility of tissues;
Development of techniques for performing organ and tissue transplantation;
Establishing the moment of removal of the organ; as well as criminal law, moral and ethical, aimed at protecting the rights of the donor and the patient, to prevent possible abuse by medical workers.
In transplantology, as in no other biomedical science, it is necessary to create ethical rules and appropriate legal (legislative) regulation of the process of transplanting biological material. On the other hand, transplantology is a method of treatment of previously hopeless patients that has taken place and is recognized by society, it is an extreme degree of medical risk and the last hope for the patient.
The adoption in 1992 of the Law "On transplantation of human organs and (or) tissues" regulated a number of legal issues of transplantation. .Nevertheless, there are still quite a lot of unresolved and controversial ethical issues.
Bibliography
1. Introduction to bioethics. [Text]/ Ed. B.G. Yudin, P.D. Tishchenko. - M.: Medicine, 1997. - 180 p.
2. Dzemeshkevich, S.L. Bioethics and deontology in clinical transplantation [Text] / S.L. Dzemeshkevich, I.V. Bogorad, A.I. Gurvich; ed. IN AND. Pokrovsky. - M.: Medicine, 1997.- 140 p.
3. Law of the Russian Federation "On transplantation of human organs and (or) tissues" (dated December 22, 1992 No. 4180-1 with additions of May 24, 2000) [Text] / Cit. according to Shamov I.A. Biomedical Ethics. - M.: OAO Publishing House Medicine, 2006. - 207 p.
4. Ivanyushkin, A.Ya. Introduction to bioethics [Text] / A.Ya. Ivanyushkin. - M.: Philosophical thought, 2001. - 192 p.
5. Instructions for ascertaining the death of a person based on the diagnosis of brain death [Text] / medical law and ethics, 2000. - No. 3.6-14.
6. Kerimov G.M. Sharia: The Law of Muslim Life. Sharia answers to the problems of our time [Text] / G.M. Kerimov. - St. Petersburg: Dilya, 2007. - 500 p.
7. Campbell, A. Medical ethics [Text] / A. Campbell, G. Gillette. - M.: GEOTAR-Media, 2007. - 400 p.
8. Mironenko, A. Cannibalism at the end of the 20th century. Transplantation: ethics, morality, law [Text] / Medical newspaper. No. 11, November, 2000.- p. 16-17.
9. Fundamentals of the social concept of the Russian Orthodox Church. Problems of bioethics [Text]// Information Bulletin of the Moscow Patriarchate DECR, 2000. -№8. pp. 73-85.
10. Organ transplant [Electronic resource] / Access mode: www.dic.academic.ru
11. Prokopenko, E.I. Viral infections and kidney transplantation [Text] / Nephrology and dialysis, 2003. No. 2. - S. 108-116.
12. Sandrikov, V.A. Clinical physiology of a transplanted kidney [Text] / V.A. Sandrikov, V.I. Sadovnikov. - M.: MAIK Nauka / Interperiodika, 2001. - 288 p.
13. Semashko, N.A. Medical ethics [Text] / N.A. Semashko. - St. Petersburg: ACIS, 2005. - 206 p.
14. Siluyanova, I.V. Bioethics in Russia: values and laws [Text] / I.V. Siluyanova. - M.: Philosophical thought, 2001. - 192 p.
15. Starikov, A.S. Legal aspects of transplantology and resuscitation [Electronic resource] / A.S. Starikov. - Access mode: www.works.ru/67/100873/index.html
16. Smirnov, A.V., Esayan, A.M. and others. Modern approaches to slowing the progression of chronic kidney disease [Text] / Nephrology, 2004. No. 3. - pp. 89-99
17. Stetsenko, S.G. Regulation of donation as a factor in the regulation of transplantation [Text] / Medical Law and Ethics, 2000 - No. 2, p. 44-53
18. Stolyarevich, E.S. On the issue of the significance of specific factors in the pathogenesis of chronic transplant nephropathy [Text] / E.S. Stolyarevich, I.G. Kim, I.M. Ilyinsky./ Nephrology and dialysis, 2001.-№3.- S. 335-344.
19. Transplantation. Management. Ed. Acad. IN AND. Shumakov. - M.: Medicine, 1995.- 391 p.
20. Fedorov, M.A. Bioethics [Text] / M.A. Fedorov. - M.: Medicine, 2000. - 251 p.
21. Filiptsev, P.Ya. Significance of early dysfunctions of a transplanted kidney [Text] / P.Ya. Filiptsev, I.B. Obukh, A.S. Sokolsky//Therapeutic archive. - 1989. - No. 7. - S. 78-82.
22. Charter of Health Workers. Pontifical Apostolate Council for Healthcare Workers. - Vatican - Moscow, 1996, p.77-79
23. Khraichik, D.E. Secrets of Nephrology [Text] / D.E. Khraichik. Translation from English. M.-SPb.: BINOM.- Nevsky Dialect, 2001. - 303 p.
24. Shumakov, V.I. Immunological and physiological problems of xenotransplantation [Text] / V.I. Shumakov, A.G. Tonevitsky. - M.: Nauka, 2000. - 144 p.
25. Shumakov, V.I. Organ conservation [Text] / V.I. Shumakov, E.Sh. Shtengold, N.A. Onishchenko. - M.: Medicine, 1975. - 250 p.
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The successes of transplantology have shown that a new, extremely promising opportunity has opened up for mankind to treat patients who were previously considered doomed. At the same time, a whole range of legal and ethical problems arose, requiring the joint efforts of specialists in the field of medicine, law, ethics, psychology and other disciplines to solve them. These problems cannot be considered solved if the approaches and recommendations developed by specialists do not receive public recognition and do not enjoy public confidence.
Organ transplantation has not become a mass type of medical care in our country, not at all because the need for it is small. The reasons are different. The most important and, alas, the most prosaic - the transplantation of any organ results in an amount that, I suspect, our average-income person cannot accumulate in a lifetime. The state is obliged to provide this expensive treatment. But we are aware of its capabilities.
Problem number two of modern transplantation is the lack of donor organs, in relation to Russian reality. It seems to be at first glance its simplest solution - to use the organs of accidentally dead healthy people. And although every day, sadly, hundreds of people die from injuries in our country alone, ensuring organ donation is not an easy task. Again, for many reasons: moral, religious, purely organizational.
In different countries of the world there are different approaches to the procurement of donor organs. In China, it is legal to take them from the corpses of those executed. For Russia, this is unacceptable. We have a moratorium on death penalty, and even before it was announced, the mystery that shrouded this action kept transplantologists out of it. Much nicer and more promising than the Chinese experience are the acts of organ donation adopted in many states. People in their youth and in full health bequeath, in case they die unexpectedly, their organs to those whom they can save their lives. Pope John Paul II called this kind of donation a micro-reproduction of the feat of Christ. If such acts were adopted in Russia, organ retrieval for direct donation would be much easier, and we could help incomparably. more seriously ill.
A few years ago in Moscow, on the basis of one of the city hospitals, the only organ harvesting center in the entire metropolis was created. And if kidneys were taken from corpses, then with the removal of hearts it was very bad. The Research Institute of Cardiology (now in Russia it has a monopoly on their transplantation) received up to ten hearts a year, while, according to medical publications alone, about a thousand cardiac patients who are on the verge of life and death are waiting for them. The collection of the liver and lungs, which requires the highest qualifications of transplantologists and is associated with a strict time limit, is practically not involved in the Moscow center at all, even though no more than 600 kidney, heart, liver, and lung transplants are performed throughout Russia per year.
And when the organ is located, it is still necessary that the immuno-genetic parameters of the donor and recipient completely match. But this is also not a guarantee of engraftment of a transplanted heart or kidney, and therefore another problem is to overcome the risk of organ rejection. Unified means that prevent the rejection process do not yet exist. The world is constantly working on new immunosuppressants. And each one is better than the previous one, and each next one is initially accepted with a bang. But as they begin to work with him, the enthusiasm subsides. All existing drugs of this series are still imperfect in different ways, all have side effects, all reduce the overall immunological response, in turn causing severe post-transplant infectious lesions, and some still hit the kidneys, liver, increase blood pressure. We have to abandon monoimmunosuppressive therapy. We have to combine different drugs, maneuver with doses of each, make compromises.
Transplantation(late lat. transplantation, from transplanto- I transplant), transplantation of tissues and organs.
Transplantation in animals and humans is the engraftment of organs or sections of individual tissues to replace defects, stimulate regeneration, during cosmetic surgeries, as well as for the purposes of experiment and tissue therapy. The organism from which the material for transplantation is taken is called the donor, the organism to which the transplanted material is engrafted is called the recipient, or host.
Types of transplant
Autotransplantation - transplantation of parts within one individual.
Homotransplantation - transplantation from one individual to another individual of the same species.
Heterotransplantation - transplantation, in which the donor and recipient belong to different species of the same genus.
Xenotransplantation - a transplant in which the donor and recipient are related different kinds, families and even groups.
All types of transplantation opposed to autotransplantation are called allotransplantation .
Transplanted tissues and organs
In clinical transplantation, autotransplantation of organs and tissues has become the most widespread, since with this type of transplantation there is no tissue incompatibility. More often, transplantations of skin, adipose tissue, fascia (connective tissue of muscles), cartilage, pericardium, bone fragments, and nerves are performed.
In vascular reconstructive surgery, vein transplantation is widely used, especially the great saphenous vein of the thigh. Sometimes resected arteries are used for this purpose - the internal iliac, deep artery of the thigh.
With the introduction of microsurgical techniques into clinical practice, the importance of autotransplantation has increased even more. Transplantation on the vascular (sometimes nerve) connections of skin, musculoskeletal flaps, muscle-bone fragments, and individual muscles has become widespread. Transplantation of fingers from the foot to the hand, transplantation of the greater omentum (fold of the peritoneum) to the lower leg, and segments of the intestine for plastic surgery of the esophagus have acquired great importance.
An example of organ autotransplantation is kidney transplantation, which is performed with extended stenosis (narrowing) of the ureter or for the purpose of extracorporeal reconstruction of the vessels of the hilum of the kidney.
A special type of autotransplantation is the transfusion of the patient's own blood in case of bleeding or deliberate exfusion (withdrawal) of blood from the patient's blood vessel 2-3 days before the operation for the purpose of its infusion (introduction) to him during the surgical intervention.
Tissue allotransplantation is used most often for transplantation of the cornea, bones, bone marrow, much less often for transplantation of pancreatic b-cells for the treatment of diabetes mellitus, hepatocytes (in acute liver failure). Rarely, brain tissue transplantation is used (during processes comorbidities Parkinson). Mass is the transfusion of allogeneic blood (blood of brothers, sisters or parents) and its components.
Transplantation in Russia and in the world
Every year, 100,000 organ transplants and more than 200,000 human tissues and cells are performed in the world.
Of these, up to 26 thousand are for kidney transplants, 8-10 thousand - liver, 2.7-4.5 thousand - heart, 1.5 thousand - lungs, 1 thousand - pancreas.
The United States is the leader among the countries of the world in terms of the number of transplants: annually, American doctors perform 10,000 kidney transplants, 4,000 liver transplants, and 2,000 heart transplants.
In Russia, 4-5 heart transplants, 5-10 liver transplants, 500-800 kidney transplants are performed annually. This figure is hundreds of times lower than the need for these operations.
According to a study by American experts, the estimated need for the number of organ transplants per 1 million people per year is: kidney - 74.5; heart - 67.4; liver - 59.1; pancreas - 13.7; lung - 13.7; heart-lung complex - 18.5.
Transplant problems
The category of medical problems arising during transplantation includes the problems of immunological selection of a donor, preparation of the patient for surgery (primarily blood purification), and postoperative therapy that eliminates the consequences of organ transplantation. Incorrect selection of a donor can lead to the process of rejection of the transplanted organ by the immune system of the recipient after the operation. To prevent the occurrence of the process of rejection, immunosuppressive drugs are used, the need for the introduction of which remains in all patients until the end of life. When using these drugs, there are contraindications that can lead to the death of the patient.
Ethical and legal issues of transplantation relate to the justification and unjustification of transplantation of vital organs in the clinic, as well as the problems of taking organs from living people and corpses. Organ transplantation is often associated with a great risk to the life of patients, many of the relevant operations are still in the category of medical experiments and have not entered clinical practice.
Taking organs from living people is associated with the principles of voluntariness and gratuitous donation, but nowadays compliance with these standards has been called into question. On the territory of the Russian Federation, the law “On transplantation of human organs and (or) tissues” dated December 22, 1992 (with amendments dated June 20, 2000) prohibits any form of organ trafficking, including those providing for a hidden form of payment in the form of any compensation and rewards. Only a blood relative of the recipient can be a living donor (genetic examination is required to obtain evidence of relatedness). Medical professionals are not eligible to participate in a transplant operation if they suspect that the organs were the subject of a commercial transaction.
The taking of organs and tissues from corpses is also associated with ethical and legal issues: in the United States and European countries, where the trade in human organs is also prohibited, the principle of “requested consent” applies, which means that without the legally formalized consent of each person to use his organs and tissues the doctor has no right to make their withdrawal. In Russia, there is a presumption of consent to the removal of organs and tissues, i.e. the law allows the taking of tissues and organs from a corpse, if the deceased person or his relatives have not expressed their disagreement with this.
Also, when discussing the ethical issues of organ transplantation, one should share the interests of resuscitation and transplantation teams of the same medical institution: the actions of the former are aimed at saving the life of one patient, and the latter - at restoring life to another dying person.
Risk groups for transplantation
The main contraindication in preparation for transplantation is the presence of serious genetic differences between the donor and recipient. If tissues belonging to genetically different individuals differ in antigens, then organ transplantation from one such individual to another is associated with an extremely high risk of hyperacute graft rejection and its loss.
Risk groups include cancer patients with malignant neoplasms with a short period after radical treatment. For most tumors, at least 2 years should elapse from completion of such treatment to transplantation.
Kidney transplantation is contraindicated in patients with acute, active infectious and inflammatory diseases, as well as exacerbations chronic diseases of this kind.
Transplant patients are also required to strictly adhere to the postoperative regimen and medical advice on the rigorous use of immunosuppressive drugs. Personality changes in chronic psychosis, drug addiction and alcoholism, which do not allow compliance with the prescribed regimen, also refer the patient to risk groups.
Requirements for donors in transplantation
The transplant can be obtained from living related donors or cadaveric donors. The main criteria for the selection of a transplant is the matching of blood groups (today, some centers have begun to perform transplant operations without taking into account group affiliation), genes responsible for the development of immunity, as well as an approximate correspondence between the weight, age and sex of the donor and recipient. Donors should not be infected with vector-borne infections (syphilis, HIV, hepatitis B and C).
At present, against the backdrop of a global shortage of human organs, the requirements for donors are being revised. Thus, dying elderly patients suffering from diabetes mellitus and some other types of diseases began to be more often considered as donors in kidney transplantation. Such donors are called marginal or extended criteria donors. The best results are achieved with organ transplantation from living donors, however, most patients, especially adults, do not have sufficiently young and healthy relatives who are able to donate their organ without compromising health. Posthumous organ donation is the only way to provide transplant care to the majority of patients who need it.
Illegal trade in organs. "Black market"
According to the United Nations Office on Drugs and Crime, thousands of illegal organ transplants are performed every year around the world. The highest demand exists for the kidneys and liver. In the field of tissue transplantation, the largest number of corneal transplants.
The first mention of the import of human organs in Western Europe refers to 1987 when law enforcement in Guatemala found 30 children destined for use in the business. Later, similar cases were registered in Brazil, Argentina, Mexico, Ecuador, Honduras, Paraguay.
The first person arrested for illegal organ trafficking was in 1996 an Egyptian citizen who bought kidneys from low-income fellow citizens for 12,000 US dollars apiece.
According to researchers, organ trafficking is particularly widespread in India. In this country, the cost of a kidney purchased from a living donor is 2.6-3.3 thousand US dollars. In some villages in Tamil Nadu, 10% of the population sold their kidneys. Before the passage of the law prohibiting the sale of organs, patients from wealthy countries came to India to perform organ transplants sold by local residents.
According to statements by Western human rights activists, the organs of executed prisoners are actively used in transplantology in the PRC. The Chinese delegation to the UN acknowledged that such a practice exists, but this happens "in rare cases" and "only with the consent of the sentenced."
In Brazil, kidney transplants are performed in 100 medical centers. There is a practice of "compensated donation" of organs here, which many surgeons consider ethically neutral.
According to Serbian media reports, the forensic commission of the UN Interim Administration in Kosovo (UNMIK) revealed the fact of the removal of organs from captured Serbs by Albanian militants during the Yugoslav events of 1999.
On the territory of the CIS, the problem of illegal trade in human organs is most acute in Moldova, where an entire underground kidney trade industry has been uncovered. The group made a living by recruiting volunteers willing to part with a kidney for $3,000 to sell it in Turkey.
One of the few countries in the world where kidney trade is legally allowed is Iran. The cost of an organ here ranges from 5 to 6 thousand US dollars.
GBOU VPO Chelyabinsk State Medical Academy
Ministry of Health and Social Development of the Russian Federation
Chair surgical dentistry
On the topic: "Transplantation. Types of transplantation. Modern problems. Tooth transplantation"
Completed by: student of group 370
Ponomarenko T.V.
Checked by: Assistant
Klinov A.N.
Chelyabinsk 2011
Introduction
Place of transplantation in modern surgery
Basic concepts
Transplant classification
Donation problems
Legal aspects
Organization of donor service
Compatibility issue
The concept of organ rejection
Autotransplantation
allotransplantation
Xenotransplantation
Tooth transplantation: background and prospects
Tooth autotransplantation
Tooth allograft
Conclusion
Bibliography
surgery transplantation donor tooth
Introduction
The development of medicine and surgery in particular has led to the fact that the vast majority of diseases are either curable completely, or it is possible to achieve a long-term remission. However, there are pathological processes, at a certain stage of which it is impossible to restore the normal functions of the organ either by therapeutic or conventional surgical methods. In this regard, the question arises of replacing, transplanting an organ from one organism to another. This problem is dealt with by such a science as transplantology.
The term "transplantology" is derived from the Latin word transplantare - to transplant and the Greek word logos - teaching.
The Great Medical Encyclopedia defines transplantology as a branch of biology and medicine that studies the problems of transplantation, develops methods for preserving organs and tissues, creating and using artificial organs.
Transplantology has absorbed the achievements of many theoretical and clinical disciplines: biology, morphology, physiology, genetics, biochemistry, immunology, pharmacology, surgery, anesthesiology and resuscitation, hematology, as well as a number of technical disciplines. On this basis, it is an integrative scientific and practical discipline.
Organ transplantation operations are quite complex, they require special equipment. But in modern transplantation, the issues of technical performance of the operation, anesthetic and resuscitation support are fundamentally resolved. The continuous improvement of medical technologies for transplantation has significantly expanded the practice of transplantation and increased the need for donor organs. In this area of medicine, as in no other, there are acute issues of moral, ethical and legal order.
1. Place of transplantation in modern surgery
The fundamentals of transplantology presented above clearly indicate its key importance for reconstructive surgery.
Back in the 18th century, the great German poet and naturalist Johann Wolfgang Goethe defined surgery as follows: “Surgery is a divine art, the subject of which is a beautiful and sacred human image. has been restored."
When comparing the volume and nature surgical interventions at different historical stages of the development of surgery, one interesting pattern is revealed.
Surgery in the first half of the 19th century, when scientific surgery was born, not to mention earlier periods, was characterized by operations associated with various deletions: organs, parts of organs, parts of the body. These operations, aimed at removing pathological foci, while saving the lives of patients, left various defects up to the loss of body parts. Such operations in the 19th century were dominant, far surpassing those of a restorative nature. It is no coincidence that historians of medicine call the 19th century the century of amputations.
In the process of development of operative surgery, the ratio between operations associated with removals and reconstructive operations is gradually changing in favor of the latter.
It is in this process that surgical transplantology is the main methodological basis.
Usage various kinds tissue and organ transplantation led to the formation of such areas of reconstructive surgery as reconstructive and plastic surgery.
Four specific tasks to be solved by modern reconstructive surgery are formulated:
strengthening organs and tissues;
replacement and correction of defects of organs and tissues;
organ reconstruction;
organ replacement.
The solution of these problems is carried out thanks to the development of new types and methods of operations of a restorative nature. Even now, such operations prevail over the operations associated with various removals, although they are necessary and are constantly being improved.
If we talk about the future of operative surgery, it is connected to a large extent with transplant surgery.
2. Basic concepts
Transplantology is a science that studies the theoretical background and practical possibilities of replacing individual organs and tissues with organs or tissues taken from another organism.
Donor - a person from whom an organ is taken (removed), which will subsequently be transplanted into another organism.
Recipient - a person in whose body a donor organ is implanted.
Transplantation is an operation to replace the patient's tissues or organs with his own tissues or organs, or those taken from another organism or created artificially.
A graft is a piece of tissue or an organ that is transplanted.
Transplantation consists of two stages: taking an organ from the donor's body and implanting it into the recipient's body. Transplantation of organs or tissues can be carried out only when other medical means cannot guarantee the preservation of the life of the recipient or the restoration of his health. The list of transplantation objects was approved by the Ministry of Health of the Russian Federation jointly with the Russian Academy of Medical Sciences. This list does not include organs, their parts and tissues related to human reproduction (eggs, sperm, ovaries or embryos), as well as blood and its components.
Three superficially similar terms are used in transplantology: "plasty", "transplantation" and "replantation". It can be difficult to distinguish between them absolutely, but nevertheless these terms can be defined as follows.
Plastic surgery is the replacement of a defect in an organ or anatomical structure with grafts without suturing blood vessels. The term is used to refer to transplantation of tissues, but not of whole organs.
A transplant is a transplantation (replacement) of an organ with the stitching of blood vessels.
A transplant is a transplantation of a donor organ without removing the same organ from the recipient.
Somewhat apart in the system of basic terms of transplantology is the term "replantation", which is understood as a surgical operation to engraft a section of tissue, organ or limb separated due to injury in the same place. The same term refers to the implementation extracted tooth into his alveolus.
3. Classification of transplants
By type of transplant
All transplant operations are divided into:
.transplantation of organs or organ complexes (transplantation of the heart, kidney, liver, pancreas, tooth, heart-lung complex) .transplantation of tissues and cell cultures (bone marrow transplantation, bone tissue, culture β- cells of the pancreas, endocrine glands). By type of donor Depending on the relationship between the donor and the recipient, the following types of transplants are distinguished. .Isotransplantation - transplantation is carried out between two genetically identical organisms (identical twins). Such operations are rare, since the number of identical twins is small, in addition, they often suffer from similar chronic diseases. .Allotransplantation (homotransplantation) is a transplant between organisms of the same species (from person to person) that have a different genotype. This is the most commonly used type of transplant. It is possible to harvest organs from relatives of the recipient, as well as from other people. .Xenotransplantation (heterotransplantation) - an organ or tissue is transplanted from a representative of one species to another, for example, from an animal to a person. The method has received extremely limited application (the use of xenoskin - pig skin, cell culture β- porcine pancreatic cells). .Explantation (prosthetics) - transplantation of a non-living non-biological substrate. It is often interpreted as implantation - a surgical operation of implanting structures and materials alien to the body into tissues. At the site of implantation of the organ .Orthotopic transplant. The donor organ is implanted in the same place where the corresponding organ of the recipient was located. .Heterotopic transplantation. The donor organ is implanted not at the location of the recipient's organ, but in another area. Moreover, the non-working organ of the recipient may be removed, or may be in its usual place. 4. Problems of donation The problem of donation is one of the most important in modern transplantology. To select the most immunologically compatible donor, each recipient needs a sufficient number of donors that meet the relevant requirements for the quality of the organs used for transplantation. There are two main groups of donors: living donors and non-viable donors (in this case, we are talking only about allotransplantation, which makes up the bulk of all organ transplant operations). living donors A paired organ, part of an organ and tissue can be taken from a living donor for transplantation, the absence of which does not entail an irreversible health disorder. To carry out such a transplant, the following conditions must be met: the donor freely and knowingly consents in writing to the removal of his organs and tissues; the donor has been warned about possible complications for his health in connection with the upcoming surgical intervention; the donor has passed a comprehensive medical examination and has the conclusion of a council of specialist doctors for the removal of organs or tissues from him; removal from a living organ donor is possible if he is in a genetic relationship with the recipient. Non-viable donors Key concepts needed to understand the legal and clinical aspects cadaveric organ donation and staff procedures are as follows: potential donor; brain death; biological death; presumption of consent. A potential donor is a patient who has been declared dead on the basis of a diagnosis of brain death or as a result of irreversible cardiac arrest. This category of donors includes patients with ascertained brain death or established biological death. The distinction between these concepts is explained by a fundamentally different approach to the operation of the removal of donor organs. Donors whose organs are harvested with a beating heart after brain death is declared Brain death occurs with the complete and irreversible cessation of all brain functions (lack of blood circulation in it), which is recorded with a beating heart and mechanical ventilation. Main causes of brain death: severe traumatic brain injury; disorders of cerebral circulation of various origins; asphyxia of various origins; sudden cardiac arrest with its subsequent recovery - post-resuscitation disease. The diagnosis of brain death is established by a commission of doctors consisting of a resuscitator-anaesthesiologist, a neuropathologist, specialists in additional research methods (all with at least 5 years of experience in the specialty) may be included. The death record is drawn up by the head of the intensive care unit, in his absence - by the responsible doctor on duty of the institution. The commission does not include specialists involved in organ retrieval and transplantation. "Instructions for stating the death of a person based on the diagnosis of brain death" does not apply to the establishment of brain death in children. The diagnosis of brain death can be reliably established on the basis of clinical tests and additional examination methods (electroencephalography, angiography of the main cerebral vessels). In case of brain death, by the time of removal, blood circulation in the organs is preserved, which improves their quality and the results of the transplant operation. Removal with a beating heart of the donor makes it possible to transplant recipients with organs that have a low tolerance to ischemia. Donors whose organs and tissues are harvested after the declaration of death Biological death is established on the basis of the presence of cadaveric changes (early signs, late signs). Organs and tissues can be removed from a corpse for transplantation if there is indisputable evidence of the fact of death recorded by a council of medical specialists. To ascertain biological death, a commission is appointed consisting of the head of the intensive care unit (in his absence, the responsible doctor on duty), the resuscitator and the forensic medical expert. In case of biological death, organ retrieval is carried out when the donor's heart is not working. Donors with irreversible cardiac arrest are called "asystolic donors". IN currently worldwide donors with "unbeatable heart" make up no more than 1-6% of all donors. In Russia, working with this category of donors is becoming a daily practice. 5. Legal aspects The activities of medical institutions related to the collection and transplantation of human organs and tissues are carried out in accordance with the following documents: "Fundamentals of the legislation of the Russian Federation on the protection of the health of citizens." Law of the Russian Federation "On transplantation of human organs and (or) tissues". Federal Law No. 91 "On Amending the Law of the Russian Federation "On Transplantation of Human Organs and Tissues". Order of the Ministry of Health of the Russian Federation No. 189 dated 10.08.1993 "On the further development and improvement of transplant care for the population of the Russian Federation." Order of the Ministry of Health of the Russian Federation No. 58 dated March 13, 1995 "On the addition to order No. 189". Order of the Ministry of Health and the Russian Academy of Medical Sciences No. 460 dated February 17, 2002, enacting the "Instruction for ascertaining human brain death on the basis of brain death." The order was registered by the Ministry of Justice of the Russian Federation No. 3170, 17.01.2002. "Instructions for determining the criteria and procedure for determining the moment of death of a person, the termination of a person's life, the termination of resuscitation", introduced by order of the Ministry of Health No. 73 dated 03/04/2003, registered with the Ministry of Justice of the Russian Federation on 04/04/2003. The main provisions of the law on transplantation: organs can be removed from the body of a deceased person only for the purpose of transplantation; removal can be carried out when there is no prior information about the refusal or objections to the removal of organs from the deceased or his relatives; doctors certifying the fact of brain death of a potential donor should not be directly involved in the removal of organs from the donor or be related to the treatment of potential recipients; medical workers are prohibited from any participation in organ transplant operations if they have reason to believe that the organs used have become the object of a commercial transaction; the body and parts of the body cannot serve as the object of commercial transactions. 6. Organization of donor service There are transplantation centers in large cities, where organ sampling centers are organized. Such centers can also be created at large multidisciplinary hospitals. Representatives of the collection centers monitor the situation in the intensive care units of the region, assessing the possibility of using critically ill patients for organ retrieval. When a brain death is declared, the patient is transferred to a transplant center, where organs are harvested for transplantation, or a special team arrives at the site to perform organ harvesting in the hospital where the victim is located. Taking into account the great need for organs for transplantation, as well as the shortage of donors observed in all economically developed countries, after declaring brain death, a complex removal of organs is usually carried out for their maximum use (multi-organ sampling). Rules for the removal of organs: removal of organs is carried out with the strictest observance of all asepsis rules; the organ is removed along with the vessels and ducts with their maximum possible preservation for the convenience of applying anastomoses; after removal, the organ is perfused with a special solution (currently, the Euro-Collins solution is used for this at a temperature of 6-10 0 WITH); after removal, the organ is immediately implanted (if there are operations in parallel in two operating rooms for organ sampling from the donor and access or removal of the own organ from the recipient) or placed in special sealed bags with Euro-Collins solution and stored at a temperature of 4-6 0 WITH. 7. Compatibility issues The problem of compatibility between the donor and the recipient is considered the most important for ensuring the normal functioning of the graft in the recipient's body. Donor and recipient compatibility Currently, the selection of a donor is carried out according to two main systems of antigens: AB0 (erythrocyte antigens) and HLA (leukocyte antigens, called histocompatibility antigens) AB0 system compatibility In organ transplantation, the optimal match of the blood group of the donor and recipient according to the AB0 system. A discrepancy in the AB0 system is also acceptable, but according to the following rules (reminiscent of the Ottenberg rule for blood transfusion): if the recipient has blood type A(II), transplantation is possible only from a donor with group A(II); if the recipient has blood type B(III), transplantation from a donor with group 0(I) and B(III) is possible; if the recipient has an AB(IV) blood group, a transplant from a donor with A(II), B(III) and AB(IV) groups is possible. Rh factor compatibility between the donor and the recipient is taken into account individually when conducting cardiopulmonary bypass and use of blood transfusion. HLA Compatibility Compatibility for HLA antigens is considered decisive in the selection of a donor. The complex of genes that control the synthesis of the main histocompatibility antigens is located on chromosome VI. The polymorphism of HLA antigens is very wide. In transplantology, loci A, B, and DR are of primary importance. To date, 24 alleles of the HLA-A locus, 52 alleles of the HLA-B locus, and 20 alleles of the HLA-DR locus have been identified. Gene combinations can be extremely diverse, and coincidence at all three of these loci at the same time is almost impossible. After determining the genotype (typing), an appropriate record is made, for example "HLA-A 5(antigen is encoded by sublocus 5 of the A locus of the VI chromosome), A 10, IN 12, IN 35, D.R. w6 "
Rejection in the early postoperative period is usually associated with incompatibility for HLA-DR, and in the long term - for HLA-A and HLA-B. Cross typing In the presence of complement, testing of several taken in different time recipient serum samples with donor lymphocytes. The result is considered positive when the cytotoxicity of the recipient's serum in relation to the donor's lymphocytes is detected. If at least one case of cross-typing revealed the death of donor lymphocytes, transplantation is not performed. Matching a donor to a recipient In 1994, the method of prospective genotyping of "waiting list" recipients and donors was widely introduced into clinical practice. Donor selection is an important prerequisite for efficiency clinical transplants. "Waiting list" - the sum of all information characterizing a given number of recipients, from which an information bank is formed. The main purpose of the "waiting list" is the optimal selection of a donor organ for a specific recipient. All selection factors are taken into account: AB0-group and preferably Rh-compatibility, combined HLA-compatibility, cross-typing, seropositivity for cytomegalovirus infection, hepatitis, control for HIV infection and syphilis, constitutional features of the donor and recipient. Currently, there are several banks with recipient data (Eurotransplant) operating in Europe. When a donor appears, from whom organ retrieval is planned, it is typed according to the AB0 and HLA systems, after which it is selected with which recipient it is most compatible. The recipient is called to the transplant center where the donor is located or where the organ is delivered in a special container, and the operation is performed. 8. The concept of organ rejection Despite the measures taken to select the most genetically close donor for each recipient, it is impossible to achieve complete identity of the genotype, recipients may experience a rejection reaction after surgery. Rejection is an inflammatory lesion of a transplanted organ (graft) caused by a specific reaction of the recipient's immune system to the donor's transplant antigens. Rejection occurs less frequently, the more compatible the recipient and donor are. Allocate rejection: .super-sharp (on operating table);
.early acute (within 1 week); .acute (within 3 months); .chronic (delayed in time). Clinically, rejection is manifested by a deterioration in the functions of the transplanted organ and its morphological changes(according to biopsy data). A sharp deterioration in the recipient's condition, associated with an increase in the activity of the immune system in relation to the transplanted organ, was called the "rejection crisis". For the prevention and treatment of rejection crises, patients after transplantation are prescribed immunosuppressive therapy. Fundamentals of Immunosuppression To reduce the activity of the immune system and prevent organ rejection after transplantation, all patients undergo pharmacological immunosuppression. In an uncomplicated course, relatively small doses of drugs are used according to special schemes. With the development of a rejection crisis, the doses of immunosuppressants are significantly increased, their combination is changed. It should be remembered that immunosuppression leads to a significant increase in the risk of infectious postoperative complications. Therefore, in the transplantation departments, it is especially necessary to observe asepsis measures. For immunosuppression, the following drugs are mainly used. Cyclosporine is a cyclic polypeptide antibiotic of fungal origin. It suppresses the transcription of the interleukin-2 gene, which is necessary for the proliferation of T-lymphocytes, and blocks T-interferon. Generally immunosuppressive action selective. The use of cyclosporine provides good graft survival with a relatively low likelihood of infectious complications. Sirolimus is a macrolide antibiotic structurally related to tacrolimus. Suppresses regulatory kinase ("sirolimus target") and reduces cell proliferation in the cell division cycle. Acts on hematopoietic and non-hematopoietic cells. It is used in basic immunosuppression as a main or additional component. There is no need to constantly monitor the concentration of the drug in the blood. Possible complications of the drug: hyperlipidemia, thrombotic microangiopathy, anemia, leukopenia, thrombocytopenia. Azathioprine In the liver, it turns into mercaptopurine, which inhibits the synthesis of nucleic acids and cell division. Used in combination with other drugs to treat rejection crises. Perhaps the development of leuko- and thrombocytopenia. Prednisolone is a steroid hormone that has a powerful non-specific depressive effect on cellular and humoral immunity. IN pure form do not use, is part of immunosuppression regimens. In high doses, it is used for rejection crises. Orthoclon. Contains anti-CD antibodies 3+-lymphocytes. Used to treat rejection crises in combination with other drugs. Antilymphocyte globulin and antilymphocyte sera. They were introduced into clinical practice in 1967 and are now widely used for the prevention and treatment of rejection, especially in patients with steroid-resistant rejection. They have an immunosuppressive effect due to the inhibition of T-lymphocytes. In addition to these drugs, other drugs are also used: calcineurin inhibitors, monoclonal and polyclonal antibodies, humanized anti-TAC antibodies. 9. Autotransplantation Autotransplantation ensures true engraftment of the transplanted substrate. With such transplants and plastics, there is no immunological conflict in the form of a transplant rejection reaction. On this basis, autotransplantation is by far the most advanced type of transplantation. Skin autoplasty is widely used in surgery: local and free autografts. To strengthen weaknesses and defects in the walls of the cavities, dense fascia, such as the wide fascia of the thigh, is used to replace tendon defects. Some bones are used for bone autoplasty: rib, fibula, crest ilium. Some blood vessels can serve as autografts: the great saphenous vein of the thigh, intercostal arteries, internal mammary arteries. The most revealing here is coronary artery bypass grafting, in which a segment of the patient's great saphenous vein is used to create a connection between the ascending aorta and the coronary artery of the heart or its branch. Autotransplantation is the use of autografts of thin, colon, stomach. Autoplastic operations are performed on the urinary tract: ureter, bladder. A very good auxiliary autoplastic material is a large omentum. Autotransplantation can also include: replantation of a tooth, traumatically severed limbs or their distal segments: fingers, hands, feet. 10. Allotransplantation There are two sources of donor tissues and organs for allotransplantation: a cadaver and a living volunteer donor. In modern surgery, skin allografts both from a corpse and from volunteer donors, various connective tissue membranes, fascia, cartilage, bones, and preserved vessels are used. An important type of allotransplantation in ophthalmology is cadaveric cornea transplantation, developed by the largest Russian ophthalmologist V.P. Filatov. The first reports of allotransplantation of the complex of skin and soft tissues of the face appeared. Allotransplantation is also a widely used in medicine transfusion of blood as a liquid tissue. The largest area of allotransplantation is organ transplantation. For the widespread use of allotransplantation, three problems are of primary importance: legal and moral support for organ retrieval both from a corpse and from a living donor-volunteer; conservation of cadaveric organs and tissues; overcoming tissue incompatibility. In the legislative provision of allotransplantation, the death criteria, in the presence of which organ retrieval is possible, the legislation regulating the rules for organ and tissue retrieval, and the possibility of using allografts from living volunteer donors, are of key importance. Conservation of donor organs and tissues makes it possible to preserve and accumulate transplant material in tissue and organ banks for use with a therapeutic purpose. The following main conservation methods are used. Hypothermia, i.e. preservation of an organ or tissue at a low temperature, at which there is a decrease in metabolic processes in tissues and a decrease in their need for oxygen. Freezing in vacuum, i.e. lyophilization, which leads to an almost complete stop of metabolic processes while maintaining cells and other morphological structures. Constant normothermic perfusion of the bloodstream of the donor organ. At the same time, normal metabolic processes are maintained in the isolated organ by delivering oxygen and necessary nutrients to the organ and removing metabolic products. It is essential for allotransplantation to overcome tissue incompatibility between the tissues of the donor and the recipient. This problem, first of all, is related to the selection of donors, donor organs and tissues that are most compatible with the recipient's body. It should be noted that allotransplantation and the problems associated with its provision are a very dynamic and rapidly developing area of clinical transplantation. 11. Xenotransplantation In modern surgery, transplantation of organs and tissues of animals to humans is the most problematic type of transplantation. On the one hand, an almost unlimited number of donor organs and tissues from different animals can be harvested. On the other hand, the main obstacle to their use is pronounced tissue immune incompatibility, leading to rejection of xenografts by the recipient's body. Therefore, until the problem of tissue incompatibility is solved, the clinical use of xenografts is limited. In a number of reconstructive operations, specially treated animal bone tissue is used, sometimes blood vessels for combined plastic surgery, temporary transplants of the liver, spleen of a pig - an animal that is genetically closest to a person. Attempts to transplant human organs of animals have not yet led to a stable positive result. Nevertheless, this type of transplantation can be considered promising after solving the problems of tissue incompatibility. 12. Tooth transplantation: background and prospects Attempts to transplant teeth have been known since ancient times. This was done by the surgeon Abul Kazim, who lived in the ninth century AD. e. The famous surgeon Ambroise Paré transplanted the healthy tooth of her maid instead of the extracted tooth to the French princess. In Russia, V. Antonevich in 1865 defended his doctoral dissertation "On replantation and transplantation of teeth." However, this operation was gradually almost completely abandoned both in our country and abroad due to a number of failures and postoperative complications. Archaeological excavations confirm the constant human desire to replace and restore lost teeth using various materials of animal, human and mineral origin. During implantation, stones were used, including precious, precious metals, ivory and other materials. The Thibody Museum at Harvard University in the United States displays a pre-Columbian human skull with gemstones implanted in the lower jaw, while the Peru Museum displays an Inca human skull with 32 implanted quartz and amethyst teeth. IN Ancient Egypt before mummification, missing teeth were restored. Transplantation of a tooth from one person to another was practiced - the teeth of the poor were rearranged by the rich. These operations were performed by barbers (hairdressers). Egypt, Greece, India, Arab countries used dental implants. In most cases, human teeth of slaves and animal teeth were used as an implant, and wealthy people were the recipients - those who had teeth transplanted. In America, the Indians used ground stones to replace a missing tooth. Attempts were made to transplant teeth in the 20th century. But this method has not been widely used for a number of reasons. Second, we need donors. Thirdly, we need a bank to store dental grafts. Fourthly, reliable sterilization of grafts is needed, which guarantees the safety of such an operation, since when transplanting biological materials, there is a high risk of transferring various infections. Fifth, transplantation is very expensive. Sixth, the results of dental transplantation are ultimately unsatisfactory. In most cases, transplanted teeth are either rejected or resorbed as a result of an immune conflict. 13. Tooth autotransplantation Autotransplantation of a tooth is the transplantation of a tooth into another alveolus. It is indicated for the removal of a decayed tooth. This operation is performed very rarely and is undertaken in cases where it is possible to transplant a healthy supernumerary or impacted tooth into the alveolus of a tooth removed due to chronic periodontitis or crown destruction due to acute trauma. The technique of the operation is the same as for replantation. Particular difficulties in this operation are the formation of an alveolus for transplanting another tooth, since there is a significant difference in the size of not only the crown, but also the roots of the removed and replanted teeth. The formation of the alveolus in accordance with the transplanted tooth often leads to additional trauma to the alveolus and removal of its periosteum, which adversely affects the engraftment process and is often complicated. 14. Tooth allograft Allotransplantation of a tooth is the transplantation of a tooth or its germ, which is taken from another person, into an artificially formed bone bed or socket of an extracted tooth. Allotransplantation of teeth is of great practical interest, and therefore has long attracted the attention of experimenters and clinicians. Transplantation of dental germs is indicated in the event of the appearance (or presence from the moment of birth) in children of defects in the dental arches that disrupt the function of chewing and speech, are not amenable to orthodontic treatment and threaten to disrupt the growth and development of the alveolar processes, in particular: a) in the absence of a child with a removable or permanent bite two or more side by side standing teeth or their rudiments lost as a result of previous periodontitis or trauma, with the preserved alveolar process and the absence of pronounced destructive changes in it; b) in the absence of large molars mandible or their rudiments in young children (6-8 years), which entails the rapid development of deformation of the alveolar process, a lag in the development of the corresponding half of the jaw; c) with congenital adentia. Based on the results of experimental studies carried out in this area by various authors the following conclusions can be drawn: ) the most favorable time for the transplantation of tooth germs is the period when they already have the main structures without their pronounced differentiation and shaping; - taking the rudiments from the donor and transplanting them to the recipient should be carried out strictly observing the requirements of asepsis and trying to minimally injure the graft; ) the transplanted rudiments must be brought into contact with the tissues of the recipient over their entire surface, thereby ensuring a strong fixation and nutrition of the sac; ) the rudiments must be isolated from the infection of the oral cavity with blind sutures or glue for the entire period of their engraftment and development. The experience of transplanting 16 rudiments of teeth taken from the corpses of children 4-8 years old 1-2 hours after their death as a result of an accidental injury showed the promise of this operation: out of 16 rudiments, 14 took root and began to erupt (after 5-8 months). The eruption of the crowns and the development of the roots were completed mainly after 2-3 years, and after 4-5 years the teeth functioned well. Encouraging results of allotransplantation of teeth in humans were obtained by V.S. Moroz: in 43 of 53 patients, teeth were preserved up to 5 "/2 years; the minimum period of tooth functioning was 2 years. In order to achieve favorable results with tooth allotransplantation, it is necessary, according to the author, to observe following conditions: ) to ensure a snug fit of the gum to the root in accordance with anatomical neck tooth - to undertake the operation only in the absence of atrophy of the gingival papillae; ) exclude traumatic blows of the antagonist on the transplanted tooth; ) remove pathologically altered tissues surrounding the top of the tooth in the recipient's alveolus; According to A.P. Cherepennikova (1968), allotransplantation of teeth is indicated in three cases: ) with primary partial adentia as a result of the absence of rudiments of permanent teeth; ) with fresh injuries of the jaws with loss of teeth; ) in the presence of teeth to be removed due to the inability to save them with therapeutic methods. Thus, the presented data on allotransplantation of teeth and their rudiments testify both to a certain perspective of the method and the need for its improvement. 15. Bone grafting The need for a bone graft Bone grafting is often necessary for complete edentulism, which is usually accompanied by severe bone resorption. At the moment of tooth extraction or dislocation, the process of defective bone remodeling begins, which inevitably leads to atrophy of the alveolar ridge. The bone graft retains its structure and function even with a decrease in the number of viable cells. The bone matrix is gradually filled with cells from adjacent tissues in a process known as "slow replacement". This mechanism does not work in skin or mucosal transplantation, therefore, in these cases, maintaining the viability of the graft cells is of paramount importance for the success of the operation. Autogenous bone grafts Most often, bone tissue transplantation is carried out, which is used to eliminate defects resulting from atrophy, trauma, tumors, as well as to correct congenital deformities. Elimination of bone defects is one of the most difficult tasks in maxillofacial surgery. Improving the techniques for obtaining, storing and using grafts has become possible due to a better understanding of the mechanisms of bone repair. Autogenous bone graft is still the only source of osteogenic cells and is considered the gold standard for reconstructive interventions in the oral cavity. Autografts are taken from the host bone: iliac crest, rib, small tibia, as well as fragments of the upper and lower jaws - the mandibular symphysis, retromolar region and branch; mound upper jaw, as well as hyperostosis of the bone. The great advantages of autogenous grafts over other bone grafts are due to the presence of viable osteoblasts and the absence of foreign antigenic proteins, as well as the fact that they have both osteoconductive and osteoinductive characteristics. Their only drawback, if you can call it that, is the additional trauma when taking the graft. In the first weeks after transplantation of an autogenous graft, the process of adaptation of bone, periosteal, and bone marrow cells occurs in it, followed by their revascularization. In the second phase, stimulation of the cells of the bone bed is observed, and they, differentiating into osteoblasts, create a bone matrix. Due to the bone-inductive activity of the cells of the bone bed, a new bone is formed, where the transplanted autograft plays the role of a bone skeleton. In the future, bone resorption and its neoformation proceed simultaneously, which leads to the incorporation of the bone graft into the host's bed. Autografts can be taken from cancellous or cortical bone, or both. If they consist of spongy bone, then after transplantation, they have a faster and more complete revascularization. Meanwhile, in autografts consisting of the cortical substance of the bone, these processes occur more slowly, and, in addition, a significant part of the transplanted bone dies, and its replacement by a new bone is, as it were, creeping. Conclusion Why implantation and not transplantation? Tooth transplantation is the transplantation of a tooth or its germ, which is taken from another person. widespread this method has not received for a variety of reasons. First, we need donors. Secondly, we need a bank to store dental grafts. Thirdly, reliable sterilization of grafts is needed, which guarantees the safety of such an operation, since when transplanting biological materials, there is a high risk of transferring various infections. And finally, the results. They are disappointing. In most cases, transplanted teeth are either rejected or resorbed as a result of an immune conflict. Implantation is the installation or introduction of a non-biological object. A non-biological object can be made from biocompatible materials that are properly sterilized to ensure patient safety. Such materials rarely cause immune conflict. Finally, implants can be mass-produced and standardized. This allows the implantation method to be widely used and to accumulate necessary experience, which is the basis for achieving good treatment results. Bibliography Gluzman A.M., Matyash I.M. Reference book surgical operations. Kyiv "Health", 1979 Kovanov VV Experiment in surgery. Moscow "Young Guard", 1989 Moore F. A history of organ transplants. Moscow "Mir", 1987 Balin VN, Alexandrov NM. Clinical operative maxillofacial surgery. Management. St. Petersburg "Special Literature" 5. Kovalenko P.P. Fundamentals of transplantology. Ed. Rostov University, 1975 Filatov A.N., Beringer Yu.V. Transplantation and replacement of tissues and organs. L., Medicine, 1990 Evdokimov A.I., Vasiliev G.A. Surgical dentistry. Moscow "Medicine", 1964 Vinogradova T.F.. Pediatric Dentistry. Moscow "Medicine" 9. Roginsky VV. Inflammatory diseases in the maxillofacial region in children. Moscow "Detstomizdat", 1998 Petrov S.V.. General surgery. Moscow "GEOTAR-Media", 2010 Kozlov V.A. Dentistry: a textbook for medical schools and postgraduate training of specialists. SPb. : SpecLit, 2011 Burian F. Development of change of fabrics. Acta Chir., 1961 Wozney J.. The bone morphogenetic protein family and osteogenesis. Mol Reprod Develop, 1992 Collins M., Mars M.. Alveolar bone grafting: A review of 115 patients. Eur J Orthod, 1998 McCarthy C. Patel RR..Dental implants and onlay bone grafts. Int J Oral Implants, 2003
