Biological criteria for transplantology. Organ and tissue transplantation
Transplantation(late lat. transplantatio, from transplanto- transplantation), tissue and organ transplantation.
Transplantation in animals and humans is the engraftment of organs or sections of individual tissues to replace defects, stimulate regeneration, during cosmetic operations, as well as for experimental purposes and tissue therapy. The organism from which the material for transplantation is taken is called a donor, the organism into which the transplanted material is implanted is called a recipient, or host.
Types of transplantation
Autotransplantation - transplantation of parts within one individual.
Homotransplantation - transplantation from one individual to another individual of the same species.
Heterotransplantation - a transplant in which the donor and recipient are related different types one kind.
Xenotransplantation - a transplant in which the donor and recipient are related different kinds, families and even squads.
All types of transplantation, as opposed to autotransplantation, are called allotransplantation .
Transplanted tissues and organs
In clinical transplantology, autotransplantation of organs and tissues is most widespread, because With this type of transplantation there is no tissue incompatibility. Transplantations of skin, adipose tissue, fascia (muscle connective tissue), cartilage, pericardium, bone fragments, and nerves are more often performed.
IN reconstructive surgery vessels, vein transplantation is widely used, especially the great saphenous vein of the thigh. Sometimes resected arteries are used for this purpose - the internal iliac artery, the deep femoral artery.
With the introduction of microsurgical technology into clinical practice, the importance of autotransplantation has increased even more. Transplantations on vascular (sometimes nerve) connections of skin, musculocutaneous flaps, muscle-bone fragments, and individual muscles have become widespread. Transplantations of toes from the foot to the hand, transplantation of the greater omentum (fold of peritoneum) to the lower leg, and intestinal segments for esophagoplasty have become important.
An example of organ autotransplantation is a kidney transplant, which is performed for extensive stenosis (narrowing) of the ureter or for the purpose of extracorporeal reconstruction of the vessels of the renal hilum.
A special type of autotransplantation is the transfusion of the patient’s own blood during bleeding or deliberate exfusion (withdrawal) of blood from the patient’s blood vessel 2-3 days before surgery for the purpose of its infusion (administration) to him during surgery.
Tissue allotransplantation is used most often for transplantation of the cornea, bones, bone marrow, and much less often for transplantation of pancreatic b-cells for the treatment of diabetes mellitus, hepatocytes (for acute liver failure). Brain tissue transplants are rarely used (for processes accompanying Parkinson's disease). Mass transfusion of allogeneic blood (blood of brothers, sisters or parents) and its components is a mass transfusion.
Transplantation in Russia and in the world
Every year, 100 thousand organ transplants and more than 200 thousand human tissue and cell transplants are performed worldwide.
Of these, up to 26 thousand are 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 in the world in the number of transplantations performed: every year American doctors perform 10 thousand kidney transplants, 4 thousand liver transplants, 2 thousand heart transplants.
In Russia, 4-5 heart transplants, 5-10 liver transplants, and 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 population 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
Medical problems that arise during transplantation include problems of immunological selection of a donor, preparing 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 recipient's immune system after surgery. To prevent the rejection process from occurring, immunosuppressive drugs are used, the need for 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 concern the justification and unjustification of a vital transplant important 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 lives of patients; many of the relevant operations are still in the category of treatment 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 norms is 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) is in force, prohibiting any form of organ trafficking, including those involving hidden form payment in the form of any compensation and rewards. A living donor can only be blood relative recipient (genetic examination is required to obtain evidence of relationship). Medical professionals are not allowed to participate in a transplant operation if they suspect that the organs have been the subject of a trade deal.
The taking of organs and tissues from corpses is also associated with ethical and legal issues: in the USA and European countries, where trade in human organs is also prohibited, the principle of “sought consent” applies, meaning that without the legally formalized consent of each person for the use of his organs and tissues the doctor has no right to remove them. 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.
Also, when discussing ethical issues of organ transplantation, the interests of resuscitation and transplantation teams of the same medical institution should be shared: the actions of the former are aimed at saving the life of one patient, and the latter - at restoring the life of 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 loss.
Risk groups include cancer patients who have malignant neoplasms with a short period of time after radical treatment. For most tumors, at least 2 years must pass from completion of such treatment to transplantation.
Kidney transplantation is contraindicated for patients with acute, active infectious and inflammatory diseases, as well as exacerbations of chronic diseases of this kind.
Transplant patients are also required to strictly adhere to the postoperative regimen and medical recommendations for the strict use of immunosuppressive drugs. Personality changes in chronic psychosis, drug addiction and alcoholism, which do not allow compliance with the prescribed regimen, also classify the patient as a risk group.
Requirements for donors for transplantation
The graft can be obtained from living related donors or cadaveric donors. The main criteria for selecting a transplant are the correspondence of blood groups (nowadays, 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 match of the weight, age and gender of the donor and recipient. Donors must not be infected vector-borne infections(syphilis, HIV, hepatitis B and C).
Currently, amid a worldwide shortage of human organs requirements for donors are being revised. Thus, dying elderly patients who suffered from diabetes mellitus and some other types of diseases began to be considered as donors more often for kidney transplants. These donors are called marginal or extended criteria donors. The best results are achieved with organ transplantation from living donors, but most patients, especially adults, do not have sufficiently young and healthy relatives who can donate their organ without harming their health. Posthumous organ donation is the only way to provide transplantation care to the majority of patients in need.
Illegal organ trade. "Black market"
According to the United Nations Office on Drugs and Crime, thousands of illegal organ transplants are performed around the world every year. The highest demand is for kidneys and liver. In the field of tissue transplantation, the largest number of operations is corneal transplantation.
The first mention of the importation of human organs into Western Europe dates back to 1987, when Guatemalan law enforcement authorities discovered 30 children intended for use in this business. Subsequently, similar cases were registered in Brazil, Argentina, Mexico, Ecuador, Honduras, and Paraguay.
The first person arrested for illegal organ trafficking was in 1996 an Egyptian citizen who was buying kidneys from low-income fellow citizens for $12,000 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 have sold their kidneys. Before the law prohibiting organ trafficking was passed, patients from wealthy countries came to India to undergo organ transplants sold by local residents.
According to statements by Western human rights activists, the organs of executed prisoners are actively used in transplantation in the PRC. The Chinese delegation to the UN admitted that such a practice exists, but this happens “in rare cases” and “only with the consent of the sentenced person.”
In Brazil, kidney transplants are performed in 100 medical centers. There is a practice here of "compensated donation" of organs, 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 that Albanian militants had harvested organs from captured Serbs during the Yugoslav events of 1999.
In the CIS, the most acute problem of illegal trade in human organs is in Moldova, where an entire underground kidney trade industry has been uncovered. The group made a living by recruiting volunteers who agreed to part with a kidney for $3,000 to sell in Turkey.
One of the few countries in the world where kidney trade is legally permitted is Iran. The cost of an organ here ranges from 5 to 6 thousand US dollars.
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transplantation death brain organ
Introduction
1. History of transplantology
2. Main problems
Conclusion
Bibliography
Introduction
Transplantology is one of the most promising areas of medical science and practice: it accumulates the latest achievements modern surgery, resuscitation, anesthesiology, immunology, pharmacology and other biomedical sciences and is based on a whole range of high medical technologies.
The beginning of the development of transplantology as a practical branch of medicine can be dated back to 1954, when American surgeons performed the first successful kidney transplant. In the Soviet Union, the first successful kidney transplant from a living donor was performed in 1965. Academician B.V. Petrovsky. The following year, he also performed a successful kidney transplant from a corpse. Until the early 60s, transplantology remained, essentially, a field of experimental surgery, without involving special attention from the public.
The situation changed after December 3, 1967, when South African surgeon Christian Barnard performed the first heart transplant from a deceased person to a patient who was on the verge of death. Heart transplantation from one person to another caused a huge public outcry. On the one hand, it became clear that a new, extremely promising opportunity for treating patients who were previously considered doomed had opened up before humanity. On the other hand, however, a whole range of legal and ethical problems have arisen that require the joint efforts of specialists in the field of medicine, law, ethics, theology, psychology and other disciplines to be resolved. Moreover, these problems cannot be considered solved if the approaches and recommendations developed by experts do not receive public recognition and enjoy public trust.
In the Soviet Union, were activities in the field of organ and tissue transplantation regulated purely by departmental means? orders and instructions of the Ministry of Health. In the early 90s in our country, in a number of performances mass media The legitimacy of transplantation activities has been questioned, especially in situations involving the collection of organs for transplantation from patients diagnosed as brain dead.
Adopted in 1992, the “Law of the Russian Federation on Transplantation of Human Organs and (or) Tissues” was an important step towards the formation legal framework transplantology. In particular, the criterion of brain death was legislatively approved, and doctors were delegated the right to collect organs for transplantation from persons in this condition. The law also established the rule of presumption of consent of potential donors and their relatives, which is generally similar to the legal norms of most European countries. A ban was introduced on the purchase and sale of organs for transplantation. At the same time, the law regulates only the most general rules of relations between doctors, recipients, donors and their relatives. There remains a significant number of problematic situations that require more subtle and detailed ethical qualifications and legal regulation.
To the most significant ethical issues The following may be included. What are the risks of commercializing transplantation? How to avoid mistakes and abuses when declaring a person’s death based on brain death? How to resolve the contradiction between the goals and objectives of the resuscitator and the doctors of the team performing the sampling donor organs? Under what model of posthumous donation is the will of a person maximally respected regarding the posthumous use of his organs for transplantation? Which criterion for the distribution of scarce donor organs is the fairest? What are the chances of using alternative organ sources?
1. History of transplantology
Attempts to carry out organ transplantation have been known for quite a long time. So in Italy in the Museum of St. The stamp has frescoes from the 15th century. which depict the 3rd century saints Cosmas and Damian, at the moment of engrafting the leg of a recently deceased Ethiopian to Deacon Justinian.
The heyday of experimental research aimed at the development of transplantation occurred at the end of the 19th and beginning of the 20th centuries. Transplantation reached the level of clinical practice in the 70-80s of the twentieth century. The founders and developers of the theoretical and experimental basis of transplantation include such outstanding domestic scientists and surgeons as Vladimir Petrovich Demikhov, Boris Vasilievich Petrovsky, Yuri Yuryevich Voronoi. In 1933, Yu.Yu. Voronoi performed the world's first kidney transplant.
1937 V.P. Demikhov performs the first implantation of an artificial heart.
The first successful heart transplant in Russia was performed by Academician V.I. Shumakov in 1986
But the key, turning point year for transplantation is considered to be 1967 - when the world's first successful human-to-human heart transplant was performed. It was carried out by a student of V.P. Demikhov, the South African doctor Christian Bernard.
Following 1967, literally next year The number of organ transplant operations numbered in the dozens, and a year later it was already in the hundreds and thousands. These years are characterized as a time of “transplantation euphoria.”
2. Main problems
The severity of ethical problems arising in this area over the years has not decreased, but increased, as evidenced by the large number international conferences, publications, and public discussions on this topic, transplantation in Russia has become legally regulated since 1992, when the Law of the Russian Federation “On Transplantation of Human Organs and (or) Tissues” was adopted.
The main ethical problems in transplantation can be grouped into four blocks (Table 1).
Table 1. Main ethical problems of human organ and tissue transplantation
The first block of ethical problems is related to commercial relations during organ transplant operations. The subsequent ones are related to the key (nodal) stages of transplantation technology: the second block - problems associated with ascertaining the death of a person according to the criteria of brain death; third - explantation (removal) of organs and (or) tissues from a corpse or living donor; the fourth block is related to the issue of distribution of existing donor organs or recipient tissues.
3. The problem of commercialization in transplantation
It is known that the purchase and sale of donor organs is prohibited by both international and Russian legislation. Thus, the Declaration of the Military Medical Academy on Maintenance and Transplantation (1987) proclaims: “The purchase and sale of human organs is strictly condemned.” In Russia, the same principle is enshrined in Article 15 of the Law of the Russian Federation “On Transplantation of Human Organs and (or) Tissues” (1992 .) and sounds like this: “A health care institution that is allowed to carry out operations to collect and procure organs and (or) tissues from a corpse is prohibited from selling them.” If foreign sources talk about the cost of a transplant, for example a heart, then we are not talking about the cost of the organ, but about the surgeon’s labor, drug costs, etc.
This prohibitive principle is in agreement with the basic law of moral relationships between people, which believes that a person cannot be considered as a means to achieve the goal of another person and the ethical understanding of a person as a person (and not a thing) with dignity, will and freedom.
Closely related to these ethical provisions is the issue of the legal status of transplants. The ban on buying and selling a person also applies to his organs and tissues. Turning into “biological materials” and representing a means of transplantation, they should not become a means of commercialization, due to their belonging to the human body. Since human organs and tissues are part of the human body, they do not correspond to the concept of a thing. And, therefore, they should not have a market equivalent and become the subject of a purchase and sale transaction. The position of the Russian Orthodox Church on this issue is also of interest, clearly expressed in the “Fundamentals of the Social Concept of the Russian Orthodox Church” (2000), which states: “The Church believes that human organs cannot be considered as an object of purchase and sale.”
However, such transactions and relationships exist. This is explained by the fact that the medical institution carrying out the removal turns into the owner of the cadaveric transplant material, with the expected consequences for it (the medical institution) and actions as a subject of the entire complex of relations that arise when handling donor organs and tissues. In conditions of market relations, the status of the owner institution transforms organs and tissues, separated and alienated from a person, into objects with the status of things. Giving the status of things to human organs and tissues separated from the body has as its logical consequence the recognition of the possibility of their purchase and sale, while erasing the distinction between a thing and a person’s personal existence. It is not difficult to determine the degree of social danger possible if ethical values are ignored as the fundamental foundations of social life.
Ethical principles limiting the commercialization of transplantation represent unique “barriers” to possible dangers. The same task is fulfilled by the ethical principles governing the diagnosis of brain death.
4. Ethical problems associated with declaring a person’s death based on a diagnosis of brain death
Historically, the criteria for human death were considered to be the absence of independent activity of two body systems: respiratory and cardiac (Table 2).
Table 2. Criteria for human death
Today, another one has been added to the traditional, historical criteria - “brain death”. There were several prerequisites for the emergence of the “brain death” criterion.
Professor I.V. Siluyanova states that the formation of the concept of “brain death” occurs under the influence of the goals and objectives of transplantology. P.D. Tishchenko notes that the introduction of a new criterion is due both to the need to make it possible to stop the senseless treatment of patients with “brain death”, and to the emergence of medical, legal and moral grounds for the collection of organs used in transplantology (Table 3).
Table 3. Factors that determined the adoption of the “brain death” criterion
Stages of forming the criterion of “brain death”:
1959 French neurologists P. Molar and M. Goulon described the state of “exorbitant coma”
1968 publication of the “Harvard” criteria for “brain death”
1981 The US Presidential Commission adopted the criterion of “complete brain death”
1992 in Russia the criterion of “brain death” was approved (Article 9 of the Law “On Transplantation”)
Currently, there are Instructions for ascertaining the death of a person based on a diagnosis of brain death, approved by Order of the Ministry of Health of the Russian Federation No. 460 of December 20, 2001. Similar documents are now available in most countries of the world, in Europe, America and Japan.
The concept of "brain death". The modern definition of human death provides the basis for the concept of “brain death.” As noted by the famous resuscitator A.M. Gurvich, accepting brain death as a criterion for human death, society was faced with several definitions of brain death.
Human death is the irreversible destruction and/or dysfunction of critical systems of the body, i.e. systems that are irreplaceable (only the brain) by artificial, biological, chemical or electronic systems.
BRAIN DEATH is:
death of the entire brain, including its stem, with irreversible unconsciousness, cessation of spontaneous breathing and disappearance of all brainstem reflexes;
death of the brain stem (in this case, signs of brain vitality, in particular their electrical activity, may remain);
death of the parts of the brain (cortex) responsible for consciousness, thinking, i.e. for the safety of a person as an individual.
Of these definitions, the most complete is the following: brain death is the death of the entire brain, including its stem, with an irreversible state of unconsciousness, cessation of spontaneous breathing and the disappearance of all brain stem reflexes.
This definition is accepted by the vast majority of countries in the world, including Russia. Brain death is considered the death of the entire brain, the brain as a whole, with the cortex, all hemispheres and departments, including the brainstem, only this is the death of the brain. If there is at least some sign of life, any of the structures of the brain, then this is anything but brain death (Table 4).
Table 4. Correspondence of states of damage to parts of the brain to the concept of “brain death”
The concepts of “clinical death”, “brain death” and “biological death” are often confused; what is the point here?
Order of the Ministry of Health of the Russian Federation No. 73 dated March 4, 2003 explains these concepts, “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 postmortem changes in all organs and systems that are permanent, irreversible, cadaveric character” (Table 5).
Table 5. Stages of human dying
In point II. the duration of guaranteed resuscitation for the patient is set to 30 minutes, in the event of “clinical death”. Only after ineffectiveness resuscitation measures within 30 minutes, doctors can begin to make a diagnosis of “brain death.”
It is important to note that although the criterion of brain death is accepted in medicine, not everyone in society clearly accepts it. It's connected with traditional ideas people about the heart, as the basis of human life, and non-acceptance of the fact that death can occur in a person with a beating heart. “I had to communicate with a surgeon who refused to make such a diagnosis (the diagnosis of “brain death” - L.L.’s note), since, in his opinion, as long as blood flow is maintained, the patient cannot be called dead,” - writes the author of the article “Transplantation” A. Palcheva. The divergence of positions on this issue is aggravated by the contradiction in the goals and objectives of the resuscitator and the doctors of the team carrying out the collection of donor organs. Thus, the goal of a resuscitator is to fight for the patient’s life with the most minimal chances, while the goal of a team of doctors involved in organ retrieval is to remove an organ from the patient in the shortest possible period of time after his death. Deputy Director of the Research Institute of Neurology of the Russian Academy of Medical Sciences, Professor M.A. Piradov states that the main path taken by doctors (reanimatologists note - L.L.) is that despite the fact that the diagnosis of “brain death” has been made, the patient continues to be treated with the help of mechanical ventilation, and usually after a few hours (maximum days) he dies, i.e., spontaneous cardiac arrest occurs. Most organs for transplantation (with the exception of kidneys) must be removed “in the bloodstream,” that is, from a patient with a beating heart. Otherwise, the organs will no longer be suitable for transplantation.
Thus, a clash of interests arises between resuscitators and members of the organ collection team.
The theological position on this issue is also ambiguous. “It is incorrect to say that the brain is the seat of the soul,” says Archpriest Sergius Filimonov. And this should be recognized when declaring a person dead when diagnosed with brain death.”
In some countries, for example in Denmark, as well as in the American states of New York and New Jersey, if a person, while alive, or his relatives after his death do not agree with the criterion of brain death, the legislation allows refusing to declare death by this criterion.
Principles for diagnosing “brain death”. How to avoid mistakes and abuses when declaring a person’s death based on brain death? The condition for an ethically impeccable diagnosis of brain death is compliance with three ethical principles:
I. The principle of a unified approach
II. The principle of collegiality
III. The principle of organizational and financial independence of teams.
I. The principle of a unified approach is to adhere to the same approach to the definition of “brain death”, regardless of whether organs are subsequently collected for transplantation.
It can be pictured figuratively like this: a team of doctors is in the field, it has all the necessary equipment, the patient is in a state of dying...
And doctors simply diagnose “brain death”, there is no one to donate organs, there is a “field” around, there is nowhere to rush. This is how “brain death” should be diagnosed in each specific case.
II. The principle of collegiality is the mandatory participation of several doctors in the diagnosis of “brain death”. Minimum permissible quantity doctors - three specialists. Neither two, nor even one, have the right to declare brain death.
This principle can significantly reduce the risk of premature diagnosis and the likelihood of abuse.
III. The next principle is the principle of organizational and financial independence of teams. In accordance with it, there should be three teams, each of which deals only with its own functions. The first one only ascertains “brain death”, the second one only carries out organ retrieval, and the third one – a team of transplantologists performs organ transplantation. Funding for these teams is carried out through parallel streams that never intersect. It is unacceptable for transplantologists to reward attending physicians based on the number of patients diagnosed with brain death. This principle is also enshrined legally; Article 9 of the Law “On Transplantation” states that transplantologists and members of teams ensuring the work of the donor service are prohibited from participating in the diagnosis of brain death. Also, according to some experts (S.L. Dzmeshkevich and others), the leader of the transplant team must be clearly aware that until the donor’s brain death is declared, none of the intended donor-recipient pair has a preferential right to life. It is not permissible to prolong the life of some patients at the expense of shortening the lives of others.
5. Ethical problems associated with regulating the process of post-mortem and intravital explantation (i.e. removal) of donor organs and (or) human tissues
According to WHO, today about 70 thousand solid organ transplants (of which 50 thousand are kidneys) and millions of tissue transplants are performed annually in the world. In the United States alone, 2,361 hearts were transplanted in 1995. The need for donor organs is increasing every year. According to the Moscow Coordination Center for Organ Donation in Russia, 5 thousand Russians annually need organ transplant operations.
There are four main sources of donor organs (Table 6).
Table 6. Types of sources of organs and tissues for transplantation.
* In this case we are talking about the use of SCs obtained from human embryos (aborted; obtained through therapeutic cloning; “extra” obtained by in vitro fertilization (IVF)). The use of SCs obtained from umbilical cord blood and adult tissues does not raise ethical objections or medical concerns.
Most organs in Russia, about 75-90%, come from deceased people, the rest from living related donors (with the exception of bone marrow donors). Sources highlighted in Fig. in italics, refer more to experimental area. They are not used in practical medicine due to their inconsistency with existing medical or ethical requirements.
The main source of organs and tissues for transplantation is cadaveric donation. There are several types of legal regulation of organ removal from a deceased person.
Types of legal regulation of organ removal from a deceased person. There are three main types: routine seizure, the principle of presumption of consent and the principle of presumption of disagreement.
The essence of the principle of routine collection is that after the death of a person, according to this principle, it becomes the property of the state. This means that the decision to remove organs is made based on the interests and needs of the state. This model existed in the Soviet health care system from 1937 and persisted until 1992. Routine seizure has lost its legitimacy in modern society, therefore, it would be more correct to note that there are two main principles: the other presumption of consent and the other presumption of disagreement. The presumption of consent applies in Russia, Austria, Belgium, Spain, the Czech Republic and Hungary and a number of other countries. The presumption of disagreement is enshrined in the laws of the USA, Canada, Germany, France, Portugal, Holland and is actually valid in Poland.
Etc. presumption of consent, also called “presumed consent” and “objection model”. The word presumption means “to assume something.” So in judicial practice The concept of “presumption of innocence” means that every person is initially innocent, guilt must be proven. In accordance with the presumption of consent in force in our country, it is assumed that every Russian initially agrees that his organs after death will be used for transplantation to others. Article 8 of the Law “On Transplantation” says: “Removal of organs and (or) tissues from a corpse is not allowed if the health care institution at the time of death of the removal was notified that during life this person or his relatives or legal representative declared his disagreement with the removal of his organs and (or) tissues after death for transplantation to a recipient.” That is, if at the time of a person’s death the doctors do not have a document from the patient that he is against it or the relatives do not come and declare this, then the organs can be taken away. The absence of an expressed refusal is interpreted by this law as consent.
However, at the same time, the law “On Burial and Funeral Business”, adopted 4 years later, is also in force in Russia. It states the opposite principle than the Law on Transplantation. In Art. 5 of the Law of the Russian Federation “On Burial and Funeral Affairs” states that in the absence of the will of the deceased, relatives have the right to authorize the removal of organs and (or) tissues from his body. Those. according to Art. 5 of the Law of the Russian Federation “On Burial and Funeral Affairs”, in the absence of the will of the deceased, the doctor is obliged to obtain consent from relatives. The existing contradiction creates a situation where the question of whether to ask permission from relatives or not depends only on the doctor’s beliefs. It can act both under the law “On Transplantation” and under the law “On Burial” (Table 7).
Table 7. Contradictions in the law in the field of regulation of the removal of organs and (or) tissues from humans
To date, the contradiction has not been eliminated and continues to persist.
This is largely due to the fact that the principle of “presumption of consent” has not only positive, but also negative sides. What are they?
The most important condition for the implementation of the right of a person or his relatives to refuse organ removal is full awareness of the population about the essence of this right and about the mechanisms for recording their refusal. However, today the majority of the population does not know that according to the law “On Transplantology” all Russians agree to be donors, and the doctor is not obliged to ask the consent of the relatives of the deceased. The majority of the population does not know the mechanism for registering a lifetime refusal. Bioethicist P.D. Tishchenko notes the fact that the refusal mechanism is explained only in the departmental instructions of the Ministry of Health, which is a significant violation of the rights of citizens. This model actually violates the principle of voluntary informed consent and does not create conditions for respecting the individual’s right to determine the fate of his or her physical body. According to Dr.Med.Sc. Professor A.V. Inaccessible at present existing principle and “even with our violent criminal population, no one can guarantee” a person’s safety.
The negative side, according to Professor I.V. Siluyanova, is that the principle of the presumption of consent forces the doctor to commit, in fact, a violent action, since an action with a person or his property without his consent is qualified in ethics as “violence.”
That is why many researchers, as well as a number of religious denominations, including the Russian Orthodox Church (in the “Fundamentals of the Social Concept”) evaluate the current law of the Russian Federation “On Organ and (or) Tissue Transplantation”, which is based on the principle of the presumption of consent, as ethically incorrect.
The positive side of the “presumption of consent” is that this principle creates a source of more organs for transplantation. This occurs due to the fact that organs are removed from those who did not express any opinion on this matter. The procedure for obtaining organs is greatly simplified for doctors; they do not need to obtain consent from relatives.
What is the essence of the opposite approach, i.e. the principle of “presumption of disagreement”, which is also called the “consent model”? As mentioned above, it operates in the USA, Germany, and France.
According to it, it is assumed that each person does not agree in advance that his organs will be transplanted to another person. Organs can be removed only if consent is obtained during the lifetime of the person himself, or the consent of relatives after his death. Depending on whether relatives have the right to make a decision, there are two versions of the principle of “presumption of disagreement”; the principle of narrow consent and the principle of broad consent. The principle of narrow consent involves taking into account only the opinion of the potential donor. The will of relatives is not taken into account. With extended consent, not only the will of the donor during his lifetime is taken into account, but also the will of the donor’s relatives after his death. The latter option is most common in Europe. The disadvantages of this model include a potential reduction in the number of organs for transplantation due to a more complex procedure for obtaining consent compared to the presumption of consent model. Although, it must be said that researchers S.G. Stetsenko, A.A. Zhalinskaya-Rericht believe that there is no significant connection between one or another principle of organ removal and the number of collected organs. As arguments indicating the absence of a significant connection between one or another principle of removal and the number of organs, these authors cite research data published in the journal New et al / King`s Institute (1994), and the fact that in Russia, despite legislation provides very broad opportunities for organ transplantation; such operations are carried out much less than in Western countries.
What are the negative and positive aspects of the principle of “presumption of disagreement”? The disadvantages of the principle of “presumption of disagreement” include the fact that for relatives the solution to such a problem as organ transplantation of the deceased is at the moment sudden death a loved one, is an excessive burden for them and does not give them the opportunity to fully and clearly consider the problem. To eliminate this shortcoming of transplantology in Germany and the Scandinavian countries, they offer the following solution, which is also called the “principle of the information model.” In accordance with it, relatives should not immediately make decisions about allowing organ removal. After informing them about the possibility of organ transplantation (removal), they can express their consent or disagreement within a specified time. At the same time, in a conversation with relatives it is also emphasized that if disagreement is not expressed within the established period, then the transplantation will be carried out. After the conversation, relatives will be required to inform in the appropriate form that the options for action are clear to them.
Thus, on the one hand, the will of the relatives will be taken into account, on the other hand, those relatives who do not have the desire to resolve this issue due to overexertion have the opportunity not to accept it.
Researchers S.A. Dzemeshkevich, I.V. Borogad believe that the situation in which a doctor must ask relatives about permission to donate, immediately after the news of death, is extreme and exceeds the permissible psychological burden on both relatives and the doctor. However, it should be noted that in world medical practice there are already approaches to solving this problem. In some American states, the law obliges doctors in specified cases to contact the relatives of the deceased with a proposal to remove organs and tissues for transplantation. Thus, the moral and psychological burden is to some extent removed from doctors. After all, it is one thing to say these words on your own behalf and quite another on behalf of the law.
The positive aspects of the “presumption of disagreement” include the fact that the doctor is freed from psycho-emotional overloads associated with committing ethically incorrect (in particular, violent) actions, which is especially significant for the doctor’s personality. Since it is known that a person who commits an action contrary to traditional moral norms inevitably exposes himself to the risk of destroying the psycho-emotional stability of his personality.
Which principle is most acceptable from an ethical point of view?
If we arbitrarily imagine a scale whose starting point corresponds to the minimum morality, and the end point to the maximum, and to place on it the existing types of legal regulation of the removal of organs from a deceased person, then the minimum level of morality can be attributed to the principle of “routine sampling”, and to the maximum - the principle “ information model" (type of "presumption of disagreement").
From the point of view of traditional ethics, the will of a person is most taken into account when using the principle of “presumption of disagreement,” and with its variety, the “information model,” the negative mental burden for relatives is minimized. According to the basic ethical principle, the voluntary lifetime consent of the donor is a condition for the legality and moral acceptability of explantation. If the will of a potential donor is unknown to doctors, they must find out the will of the dying or deceased person by contacting relatives.
In the meantime, in the current situation in our country, we can only provide legal advice for those who do not agree to posthumous donation. Thus, lawyers recommend that all citizens who do not agree that their organs will be removed after death, make a statement to the chief physician through their attending physician about their position. This should best be done at the time the patient obtains voluntary informed consent for medical intervention.
6. Ethical and legal regulation of lifetime donation of human organs and (or) tissues
Now we talked about regulating the collection of organs from deceased people. Can living donor organs be used for transplantation? Yes, they can, as a rule, paired organs are used, for example a kidney, or a part of an organ is taken - a lobe of the liver. If we say that the removal of donor organs is allowed, then what are the conditions for its implementation? Removal of organs and tissues from a living donor for transplantation to a recipient in accordance with Art. 11 of the Law of the Russian Federation “On Transplantation” is permitted subject to the following conditions:
* If the donor freely and consciously expressed consent in writing to the removal of his organs or tissues;
* If the donor is warned about possible complications for his health in connection with the upcoming surgical intervention to remove organs or tissues;
*If the donor has undergone comprehensive medical examination and there is a conclusion from a council of specialist doctors on the possibility of removing his organs or tissues for transplantation;
* If the donor is in a genetic relationship with the recipient, i.e. if he is a relative of the recipient. The exception is cases of bone marrow transplantation.
The condition regarding the mandatory presence of a genetic link is due to the need to exclude the possibility of abuse and attempts to reward the donor for the donated organ. The likelihood of financial relationships between relatives is much less than between strangers. In addition, in the case of related transplants, the likelihood of immune organ rejection is reduced.
7. Criteria for the distribution of donor organs and (or) human tissues
The fourth block of ethical problems is associated with the stage of distribution of existing donor organs. To consider the procedure for allocating donor organs, we need to answer the following questions. How are donor organs distributed? Based on what criteria does this happen? Does a person’s social, marital status, or income affect the distribution mechanism?
In accordance with accepted international and domestic principles, the answer to the last question is “No.” The main criterion influencing the doctor’s decision is the degree of immunological compatibility of the donor-recipient pair. In accordance with it, an organ is given not to someone who has a higher or lower position, not to someone who has more or less income, but to someone to whom it is more suitable in terms of immunological indicators. This approach is similar to how blood transfusion is performed. The immunological and biological data of a person in need of an organ transplant are entered into a database, the so-called. "waiting list". Waiting lists exist at different levels, e.g. major cities, such as Moscow, at the regional, regional and even national level.
On the other hand, there is a database of donor organs and their immunological parameters. When a donor organ becomes available, its biological data begins to be compared with the biological parameters of people on the “waiting list”. And with whose parameters the organ is more compatible, it is given to the recipient. This principle of distribution is considered the most fair and is fully justified medical point vision, as it helps reduce the likelihood of rejection of this body.
But what if the donor organ is suitable for several recipients (in need of a transplant) from the list? In this case, the second criterion comes into play - the criterion of the severity of the recipient. The condition of one recipient allows him to wait another half a year 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. Usually this is where the distribution ends.
However, what to do in a situation where an organ is almost equally suitable for two recipients, and they are both in critical condition and can't wait long? In this case, the decision is made based on the priority criterion. The doctor must take into account the length of time the recipient has been on the “waiting list.” Preference is given to those who were previously on the “waiting list” (Table 8).
Table 8
In addition to the three mentioned criteria, the distance, or rather the distance of the recipient from the location of the donor organ, is also taken into account. The fact is that the time between organ removal and transplantation is strictly limited; the organ with the shortest time for transplantation is the heart, about five hours. And if the time spent covering the distance between the organ and the recipient is greater than the “life” time of the organ, then the donor organ is given to the recipient located at a closer distance.
The likelihood of an organ transplant directly depends not only on the number of “offers” of donor organs, but also on the size of the “waiting list” - the list of people in need of a transplant. The higher the number of typed (with identified immunological parameters) recipients, the higher the chance that the immune parameters of someone from this list coincide with the immune parameters of the resulting donor organ. The degree of compatibility in this case can be very high. And with a list of recipients of several hundred people, there is a probability that the donor organ that appears will either be “unsuitable” for any of the recipients on the “waiting list”, or “suitable”, but with a low degree of compatibility. In this regard, it seems promising to maximize the unification of “waiting lists” of various levels (from city to interstate).
Additional ethical issues arising from the distribution of donor organs and human tissues.
Nowadays, many candidates are denied transplantation. Transplantologists explain this by the fact that if donor organs are transplanted into a patient without diseases accompanied by damage to the peripheral vascular system, then his chances of long-term survival will be quite high. The prognosis for candidates with damage to the vascular system is less optimistic, so many of these “borderline” patients are not included on the transplant waiting list.
The question of the possibility of a second and even third sequential transplantation is acute, since in patients who have undergone retransplantation, the effect is usually weaker than after the first operation. This, according to transplantologists, in particular Academician V.I. Shumakov, creates conditions for discussing the issue of the need to use valuable donor organs for patients whose prognosis is likely to be less satisfactory.
Risks for the recipient cannot be completely excluded. As researcher A.G. notes Tonevetsky, now many organs are taken from random donors, in whom the presence of known infections cannot be ruled out: hepatitis B and C, AIDS. In addition, the possibility of infections such as cytomegalovirus and Epstein-Bar virus, which can cause the development of malignant tumors, cannot be excluded.
8. Ethical considerations pediatric transplant
The problem of donor organ transplantation for children is acute throughout the world. Every year in the United States, 40 to 70% of children on waiting lists die before suitable organs become available to them. Of the 5 thousand Russians who annually need organ transplants, 30% are children. According to the Research Institute of Children's Health of the Russian Academy of Medical Sciences, 200 children annually need to receive a kidney, 100 children need a liver, and 150 need a heart transplant.
Currently, the most pressing question is about the possibility of transplanting organs such as kidneys, liver, heart and heart-lung complex to children. What is the situation with the possibility of transplanting these organs to children in Russia?
When considering the situation in pediatric transplantation in Russia, it is necessary to pay attention to two positions: the first is what pediatric transplantation is in our country today, the second is innovations, the immediate plans of the Ministry of Health and Social Development to overcome the shortcomings and develop the current domestic system of pediatric transplantation.
The pediatric transplant system currently operating in Russia.
Today in our country, the sources of organs permitted by law for transplantation to children (patients under 18 years of age) are (in order of importance):
1. adult living related donors (one of the parents). Transplanted organs: kidneys, liver (lobe).
2. adult deceased donors (unrelated). Transplanted organs: kidneys, liver.
3. operations carried out abroad on a paid basis. Transplanted organs: heart, heart-lung complex, and other organs.
Adult living related donors. The vast majority of children who require liver and kidney transplants receive organs from adult living related donors. Most often, the donor is one of the child's parents.
Today, kidney and liver transplants for children from related donors are quite successful. So member.-cor. RAMS specialist, Russian Research Center of Chemistry named after. acad. B.V. Petrovsky RAMS S. Gauthier states success in solving even severe cases: “We transplanted a kidney and a liver simultaneously into a six-year-old boy from a mother incompatible with the child’s blood type. We managed to accurately select drug therapy prepare his body. He has grown up and is developing well.”
To exclude the possibility of a donor who is not a relative of the child participating in a related transplant, the relationship is checked in the most scrupulous way at the centers performing the transplant. Even when it comes to mother and child.
Adult deceased donors. In October 2007, at the Russian Scientific Center for Surgery named after Acad. B.V. Petrovsky was transplanted one year old child a kidney from a fifty-two-year-old man who died of traumatic brain injury. The number of children waiting for a kidney is the largest. Now both children and adults in need of a donor kidney are on the same waiting list. Everyone has the same chances. The criterion for organ distribution is the compatibility criterion. The one who best fits ten parameters will receive a kidney. Average duration The wait in Moscow for a cadaveric organ is several years. The life of a child, unlike the life of an adult, directly depends on the waiting period. The life of an adult does not depend on whether he lives on dialysis or has had a kidney transplant. 30% of children die after 5 years of dialysis from the complications it caused.
However, they do not grow on dialysis. According to M. Kaabak, children in this line should go first. If a child waits six months for a kidney, it is urgent; if a year, then it is super urgent. Given the exceptional impact of the waiting period for a donor organ on the development and life expectancy of a child, in our opinion it would be appropriate to give children priority on the waiting list.
Operations carried out abroad on a paid basis.
A child is sent abroad for a paid transplant in two cases:
the child needs a form of assistance that is not available or not provided in Russia, for example, heart transplants for children;
the family of a sick child has its own financial resources sufficient to pay for his treatment abroad.
In the first case, payment for treatment is carried out from the budgets of the state healthcare system different levels, in the second, respectively, from the personal funds of the family of the child suffering from the disease.
Today there are also precedents for organizing charity events and various events, the purpose of which is to raise funds aimed at helping children in need of expensive treatment.
There is a position that the huge amount of money that Russia is forced to send abroad today for the treatment of dying children, provided that pediatric transplantation is properly organized in our country, would allow us to treat twice or three times as many children here. A liver transplant operation abroad costs about $100 thousand.
In most countries, such operations are paid for by insurance companies, in a number of countries - by the state (Great Britain, Russia).
Sources of organs for transplantation to children currently prohibited by the domestic law on transplantation include:
1. adult living unrelated donors. Transplanted organs: kidneys, part of the liver
2. child posthumous donation. It is possible to transplant: heart and other organs.
Adult living unrelated donors. In Russia, unrelated transplants from living donors are now prohibited for any recipients. Article 11 of the Law of the Russian Federation On Transplantation of Human Organs and (or) Tissues states the following condition: “if the donor is in a genetic relationship with the recipient, i.e. if he is a relative of the recipient. The exception is cases of bone marrow transplantation.” The reasons for limiting the circle of donors to relatives were mentioned in the section Ethical and legal regulation of lifetime donation of human organs and (or) tissues.
Child posthumous donation. In our country, transplanting organs from a deceased child to a living child is prohibited, which means transplanting such an organ to children is not possible. The Ministry of Health and Social Development is currently working on “Instructions for ascertaining the death of a child based on a diagnosis of brain death,” the adoption of which may take place this year. This will make it possible to perform previously unavailable operations on children in our country.
Plans of the Ministry of Health and Social Development to overcome shortcomings and develop the domestic system of pediatric transplantation.
Project “Instructions for declaring the death of a child based on a diagnosis of the brain.” In 2007, in an interview with the Komersant newspaper, Deputy Minister of the Ministry of Health and Social Development Vladimir Starodubov reported that the ministry had almost completed work on a document regulating the procedure for child donation. The document is called “Instructions for declaring the death of a child based on a diagnosis of the brain.” However, as of January 2009, a document designed to regulate posthumous child donation has not been adopted.
The instructions are compiled taking into account the socio-ethical significance (the object is a child) and medical specifics (great compensatory possibilities child's body). Comparison of the main provisions of the project “Instructions for ascertaining the death of a child based on a diagnosis of brain death” and the currently valid for adults “Instructions for ascertaining the death of a person based on a diagnosis of brain death,” approved by order of the Ministry of Health of the Russian Federation No. 460 of December 20, 2001 (Table 9)
Table 9. Comparative table of the main provisions of the draft “children’s” instructions and current instructions"for adults"
In the draft “Instructions for ascertaining the death of a child based on a diagnosis of the brain,” the composition of the commission establishing the diagnosis of brain death in a child has been strengthened, the period of observation of children has been increased to 120 hours, and the principle governing the moment of organ removal from a child is the principle of “presumption of disagreement.” (required parental consent). The latter requirement - mandatory parental permission - creates exceptional ethical and legal conditions for taking into account the interests of a dying child.
9. Ethical aspects of cell transplantation
The ability of human stem cells to develop into cells various organs, replacing dying cells and thereby ensuring the restoration of the integrity of the organ, became the basis of a new direction in medicine - cell transplantation or regenerative medicine, the objectives of which are to obtain treatment methods for the most various diseases(atherosclerosis, blood diseases, Parkinson's disease, diabetes mellitus).
The main ethical problem with the use of stem cells is related to the question of their source. Sources of stem cells can be divided into ethically acceptable and ethically unacceptable. Obtaining stem cells from organs and tissues of an adult body, umbilical cord blood and placental tissue does not raise any objections. However, the use of “extra”, “unclaimed” human embryos obtained from in vitro fertilization(IVF), aborted embryos and embryos created through therapeutic cloning are assessed as morally unacceptable. The use of a human embryo as a raw material for stem cell production is a violation of the first principle of the Declaration on Medical Abortion adopted by the WMA in 1983: “The fundamental moral principle of the physician is respect for human life from the moment of conception.” Assembly World Organization The 1970 World Health Organization (WHO) also expresses its position on the status of the human embryo in a resolution reaffirming the 1948 Geneva Declaration: “I will certainly respect the life of others from the moment of conception.” The position that maximally protects a person and takes into account his dignity is a position that recognizes the beginning of a person’s life at the moment of fusion of male and female reproductive cells. The use of human embryos obtained by artificial insemination and therapeutic cloning as a source of stem cells means the destruction of embryos. The question arises, why destroy embryos if there are alternative sources of stem cells that do not require the use and destruction of embryos?
It is also ethically incorrect to use tissue from an aborted fetus. The basis for the incorrectness is that consent to terminate a pregnancy is not the same as consent to the use of an aborted fetus in research. Using a fetus in research without parental consent may be considered a violation of the principle of informed consent. In addition, the use of aborted fetuses may provoke an increase in the number of abortions, while it will not be possible to cover the needs for stem cells. For example, it is estimated that to treat, for example, one patient with diabetes mellitus, stem cells from 3-5 aborted embryos will be needed. If we multiply this number by the number of patients with this disease in the country (in Russia there are 8 million people, in the USA in 2000 - 12 million), then the number of embryos needed only for the treatment of diabetes mellitus alone will exceed the number of abortions performed in the country per year (1,582 thousand were made in Russia in 2006). But stem cell transplantation is expected to be used to treat many other diseases. The situation of supply-demand mismatch can inevitably result in clinics paying for abortions (“contract killing”).
Another problem in regenerative medicine is the continuing serious risk of embryonic stem cells becoming tumor cells, instead of, say, the necessary cardiomyocytes, neurons or pancreatic cells. So at the round table “Stem cells - how legal is it?”, held at the MMA named after. THEM. Sechenov, Academician of the Russian Academy of Medical Sciences, Director of the Institute of Experimental Cardiology of the Russian Cardiological Research and Production Complex of the Ministry of Health and Social Development of the Russian Federation Vladimir Smirnov, emphasized that only umbilical cord blood stem cells should be used in practice. They have already been tested for the treatment of approximately 45 types of diseases, their future is enormous. But the use of embryonic stem cells is doubtful.
And when they enter an adult body, these cells, at best, are rejected by the immune system, at worst, they will give rise to a tumor (teratoma). The incidence of tumors reaches 30%. There is not a single proof to date of the effectiveness of treatment with embryonic cells published in peer-reviewed scientific journals,” explained V. Smirnov. When using abortion material, it should be taken into account that at the stage of development up to 14 weeks, the embryo does not have tissue rejection mechanisms. The tissue can take root in body, if it takes root, then in this case it is a tumor tissue. Embryonic tissues do not have recognition signs - “friend or foe”, and this is quite dangerous.
Until this risk is completely eliminated, it would be ethically unjustifiable to recommend this method to patients.
10. Medical and ethical problems xenotransplantation
Xenotransplantation is the transplantation of animal organs into humans.
Today, due to the existing shortage of donor organs, there is an opinion that animal organs can serve as an alternative to scarce human organs. It is known that pig tissues have the greatest compatibility with human tissues. However, despite ongoing experiments and research on xenotransplantation (including in the Federal scientific center transplantology and artificial organs named after. ak. IN AND. Shumakov" of the Ministry of Health and Social Development of the Russian Federation), today such animal organs as the heart, liver, kidneys are not used for human transplants. They are not used for two reasons: the first is the immune rejection of animal organs by the human body, the second is the risk of transferring infections from the animal to to a person.
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GBOU VPO Chelyabinsk State Medical Academy
Ministry of Health and Social Development of the Russian Federation
Department of 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
Transplantation classification
Donation problems
Legal aspects
Organization of donor service
Compatibility issue
Concept of organ rejection
Autotransplantation
Allotransplantation
Xenotransplantation
Tooth transplantation: background and prospects
Autologous tooth transplantation
Tooth allotransplantation
Bone grafting
Conclusion
Bibliography
surgery transplantology donor tooth
Introduction
The development of medicine and surgery in particular has led to the fact that the vast majority of diseases are either completely curable or long-term remission can be achieved. However, there are pathological processes at a certain stage of which it is impossible to restore the normal functions of the organ using either therapeutic or conventional surgical methods. In this regard, the question arises of replacement, transplantation of 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 - study.
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, and creating and using artificial organs.
Transplantology has incorporated 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 transplant operations are quite complex and require special equipment. But in modern transplantology the issues of technical execution of the operation, anesthesiological and resuscitation support have been fundamentally resolved. Continuous improvement of medical technologies for transplantation purposes has significantly expanded the practice of transplantation and increased the need for donor organs. In this area of medicine, more than in any other, moral, ethical and legal issues are acute.
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 in the following way: “Surgery is a divine art, the subject of which is the beautiful and sacred human image. It must take care that the wonderful proportionality of its forms, damaged somewhere, is restored again.”
When comparing the volume and nature of surgical interventions at different historical stages of the development of surgery, one interesting pattern is revealed.
For surgery in the first half of the 19th century, when scientific surgery was born, not to mention more early periods, operations associated with various removals were typical: organs, parts of organs, parts of the body. These operations, aimed at removing pathological foci, saving the lives of patients, left various defects, including the loss of body parts. Such operations were dominant in the 19th century, far superior to operations of a restorative nature. It is no coincidence that medical historians call the 19th century the century of amputations.
In the process of development of operative surgery, the ratio between operations associated with removals and operations of a reconstructive nature gradually changes in favor of the latter.
It is in this process that surgical transplantology is the main methodological basis.
The use of various types of tissue and organ transplantation has led to the formation of such areas of reconstructive surgery as reconstructive and plastic surgery.
Four specific problems solved by modern reconstructive surgery have been formulated:
strengthening organs and tissues;
replacement and correction of defects in organs and tissues;
organ reconstruction;
organ replacement.
The solution to these problems is carried out through the development of new types and methods of operations of a restorative nature. Already, such operations predominate over operations associated with various removals, although they are also necessary and are constantly being improved.
If we talk about the future of operative surgery, it is largely connected with transplant surgery.
2. Basic concepts
Transplantology is a science that studies the theoretical background and practical possibilities of replacement individual organs and tissues by organs or tissues taken from another organism.
A donor is a person from whom an organ is taken (removed), which will subsequently be transplanted into another body.
A recipient is a person into 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 taken from another organism or created artificially.
A transplant is a transplanted area of tissue or organ.
Transplantation consists of two stages: taking an organ from the donor’s body and implanting it into the recipient’s body. Organ or tissue transplantation can only be carried out if other medical supplies cannot guarantee the preservation of the recipient’s life or restoration of his health. The list of transplant objects was approved by the Ministry of Health of the Russian Federation together with the Russian Academy medical sciences. This list does not include organs, their parts and tissues related to human reproduction (egg, sperm, ovaries or embryos), as well as blood and its components.
In transplantology, three outwardly similar terms are used: “plasticity,” “transplantation,” and “replantation.” It can be difficult to distinguish 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 the transplantation of tissues, but not entire organs.
A transplant is the transplantation (replacement) of an organ with stitching of blood vessels.
A transplant is the transplantation of a donor organ without removing the same organ from the recipient.
The term “replantation” stands somewhat apart in the system of basic terms of transplantology, which is understood as a surgical operation to engraft a section of tissue, organ or limb separated due to injury onto same place. The same term refers to the introduction of an extracted tooth into its own alveolus.
3. Classification of transplants
By type of transplant
All transplant operations are divided into:
.transplantation of organs or complexes of organs (transplantation of heart, kidney, liver, pancreas, tooth, heart-lung complex) .tissue and cell culture transplantation (bone marrow, bone tissue, culture β- pancreatic cells, endocrine glands). By donor type Depending on the relationship between the donor and the recipient, the following types of transplantations are distinguished. .Isotransplantation - a transplant is carried out between two genetically identical organisms (identical twins). Such operations are rare because the number of identical twins is small and they often suffer from similar chronic diseases. .Allotransplantation (homotransplantation) is a transplantation between organisms of the same species (from person to person) that have different genotypes. This is the most commonly used type of transplant. It is possible to collect 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 (use of xenoskin - pig skin, cell culture β- porcine pancreas cells). .Explantation (prosthetics) - transplantation of a non-living, non-biological substrate. It is more often interpreted as implantation - a surgical operation of implanting structures and materials alien to the body into tissue. At the site of organ implantation .Orthotopic transplantation. The donor organ is implanted in the same place where the corresponding recipient organ was located. .Heterotopic transplantation. The donor organ is implanted not at the site of the recipient's organ, but in another area. Moreover, the recipient’s non-functioning organ can be removed, or it can remain 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 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 Can be removed from a living donor for transplantation paired organ, part of an organ and tissue, the absence of which does not entail irreversible health problems. To carry out such a transplantation, the following conditions must be met: the donor freely and consciously consents in writing to the removal of his organs and tissues; the donor is warned about possible complications for his health in connection with the upcoming surgical intervention; the donor has undergone a comprehensive medical examination and has a conclusion from a council of medical specialists for the removal of organs or tissues from him; Removal of organs from a living donor is possible if he is in a genetic relationship with the recipient. Non-viable donors Key concepts needed to understand legal and clinical aspects organ cadaveric donation and procedures for personnel are as follows: potential donor; brain death; biological death; presumption of consent. A potential donor is a patient declared dead based on a diagnosis of brain death or as a result of irreversible cardiac arrest. This category of donors includes patients with confirmed brain death or established biological death. The distinction between these concepts is explained in principle different approach to the operation of removing donor organs. Donors whose organs are harvested with the heart beating after brain death has been declared Brain death occurs with a complete and irreversible cessation of all brain functions (lack of blood circulation in it), recorded during a beating heart and mechanical ventilation. Main causes of brain death: severe traumatic brain injury; cerebrovascular accidents of various origins; asphyxia of various origins; sudden stop of cardiac activity followed by its recovery - post-resuscitation illness. The diagnosis of brain death is established by a commission of doctors consisting of a resuscitator-anesthesiologist, a neurologist, and may include specialists in additional research methods (all with at least 5 years of experience in the specialty). The protocol for establishing death is drawn up by the head of the intensive care unit, or, in his absence, by the responsible doctor on duty at the institution. The commission does not include specialists involved in organ retrieval and transplantation. “Instructions for ascertaining the death of a person based on a diagnosis of brain death” do not apply to establishing 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 great vessels of the brain). In case of brain death, blood circulation in the organs is preserved at the time of removal, which improves their quality and the results of the transplant operation. Removal of a donor while the heart is beating makes it possible to transplant organs with low tolerance to ischemia into recipients. Donors whose organs and tissues are removed after death is declared Biological death is determined based on the presence cadaveric changes(early signs, late signs). Organs and tissues can be removed from a corpse for transplantation if there is indisputable evidence of death, recorded by a council of medical specialists. For the record biological death appoint a commission consisting of the head of the intensive care unit (in his absence, the responsible doctor on duty), a resuscitator and a forensic expert. In case of biological death, organ removal is carried out when the donor’s heart is not working. Donors with irreversible cardiac arrest are called “asystolic donors.” Currently, “unbeatable heart” donors make up no more than 1-6% of all donors worldwide. In Russia, working with this category of donors is becoming a daily practice. 5. Legal aspects Activity medical institutions related to the collection and transplantation of human organs and tissues is carried out in accordance with the following documents: "Fundamentals of the legislation of the Russian Federation on protecting the health of citizens." Law of the Russian Federation "On transplantation of human organs and (or) tissues." Federal Law No. 91 “On Amendments to 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 August 10, 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 of 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 of February 17, 2002, introducing the “Instructions for ascertaining the death of a person’s brain on the basis of brain death.” The order was registered by the Ministry of Justice of the Russian Federation No. 3170, 01/17/2002. “Instructions for determining the criteria and procedure for determining the moment of a person’s death, termination of a person’s life, termination of resuscitation measures,” introduced by order of the Ministry of Health No. 73 of 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 preliminary 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 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 body parts cannot be the object of commercial transactions. 6. Organization of donor service In large cities there are transplant centers, and organ collection centers are organized within them. Such centers can also be created at large multidisciplinary hospitals. Representatives of collection centers are monitoring the situation in intensive care units in the region, assessing the possibility of using critically ill patients for organ collection. When brain death is determined, the patient is transferred to a transplant center, where organs are removed for transplantation, or a special team goes to the site to perform organ removal in the hospital where the victim is located. Considering the great need for organs for transplantation, as well as the shortage of donors observed in all economically developed countries, after declaring brain death, complex organ retrieval is usually carried out for their use. maximum use(multi-organ sampling). Rules for organ retrieval: organs are removed in strict compliance with all aseptic rules; the organ is removed along with the vessels and ducts, preserving them as much as possible for the convenience of anastomosis; After removal, the organ is perfused with a special solution (currently, Euro-Collins solution is used for this at a temperature of 6-10 0 WITH); after removal, the organ is immediately implanted (if in parallel there are operations in two operating rooms to collect the organ from the donor and access or remove the recipient’s own organ) 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 donor and recipient compatibility is considered the most important to ensure the normal functioning of the graft in the recipient's body. Compatibility of donor and recipient Currently, donor selection is carried out according to two main antigen systems: AB0 (erythrocyte antigens) and HLA (leukocyte antigens, called histocompatibility antigens) AB0 system compatibility During organ transplantation, it is optimal to match 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 Ottenberg’s rule for blood transfusion): if the recipient has blood type A(II), a transplant is possible only from a donor with type A(II); if the recipient has blood group B(III), a transplant from a donor with group 0(I) and B(III) is possible; if the recipient has blood group AB(IV), a transplant from a donor with group A(II), B(III) and AB(IV) is possible. Rh compatibility between donor and recipient is taken into account individually when performing artificial circulation and using blood transfusion. HLA compatibility HLA antigen compatibility is considered decisive when selecting 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, the A, B and DR loci are of primary importance. Currently, 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. Combinations of genes can be extremely diverse, and a match at all three of these loci at the same time is almost impossible. After determining the genotype (typing), an appropriate entry is made, for example, “HLA-A 5(antigen is encoded by sublocus 5 of locus A of chromosome VI), A 10, IN 12, IN 35, DR w6 "
Rejection in the early postoperative period is usually associated with HLA-DR incompatibility, and in the long term - with HLA-A and HLA-B. Cross typing In the presence of complement, several samples taken are tested. different time samples of recipient serum with donor lymphocytes. The result is considered positive when the cytotoxicity of the recipient's serum towards the donor's lymphocytes is detected. If in at least one case of cross-typing the death of the donor's lymphocytes is detected, transplantation is not performed. Matching donor to recipient In 1994, a method of prospective genotyping of “waiting list” recipients and donors was widely introduced into clinical practice. Donor selection is an important prerequisite for the effectiveness of clinical transplantations. “Waiting list” is the sum of all information characterizing a given number of recipients; an information bank is formed from it. 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: ABO group and preferably Rh compatibility, combined HLA compatibility, cross typing, seropositivity for cytomegalovirus infection, hepatitis, control for HIV infection and syphilis, constitutional characteristics of the donor and recipient. Currently, there are several banks with data on recipients in Europe (Eurotransplant). When a donor appears from whom organ removal is planned, he is typed using the AB0 and HLA systems, after which he is selected with which recipient he 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 similar donor for each recipient, it is impossible to achieve complete genotype identity; 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 transplantation antigens. Rejection occurs less frequently the more compatible the recipient and donor are. Rejection is distinguished: .hyperacute (on the 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, is called a “rejection crisis.” To prevent and treat rejection crises, patients after transplantation are prescribed immunosuppressive therapy. Basics of Immunosuppression To reduce the activity of the immune system and prevent organ rejection after transplantation operations, all patients undergo pharmacological immunosuppression. In uncomplicated cases, relatively small doses of drugs are used according to special regimens. With the development of a rejection crisis, the dose of immunosuppressants is significantly increased and their combination is changed. It should be remembered that immunosuppression leads to a significant increase in the risk of infectious diseases. postoperative complications. Therefore, aseptic precautions must be observed especially carefully in transplant departments. The following drugs are mainly used for immunosuppression. Cyclosporine is a cyclic polypeptide antibiotic of fungal origin. Suppresses the transcription of the interleukin-2 gene, necessary for the proliferation of T-lymphocytes, and blocks T-interferon. In general, the immunosuppressive effect is selective. The use of cyclosporine ensures good graft survival with a relatively low likelihood of infectious complications. Sirolimus is a macrolide antibiotic that is structurally related to tacrolimus. Suppresses regulatory kinase (“target of sirolimus”) and reduces cell proliferation in the cell division cycle. Acts on hematopoietic and non-hematopoietic cells. Used in basic immunosuppression as the 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 is converted into mercaptopurine, which inhibits the synthesis of nucleic acids and cell division. Used in combination with other drugs to treat rejection crises. Leuko- and thrombocytopenia may develop. Prednisolone - steroid hormone, which has a powerful nonspecific depressive effect on cellular and humoral immunity. It is not used in its pure form; it is part of immunosuppressive regimens. In high doses it is used for rejection crises. Orthoclone. Contains antibodies to CD 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. Currently, they are 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 the listed drugs, other agents 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 plastic surgery, there is no immunological conflict in the form of graft rejection. For this reason, autotransplantation is by far the most advanced type of transplantation. In surgery, skin autoplasty is widely used: local and free autografts. To strengthen weak points and defects in the walls of cavities, dense fascia, such as the fascia lata, 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 indicative here is coronary artery bypass grafting, in which to create a connection between the ascending aorta and coronary artery the heart or its branch, a segment of the great saphenous vein of the patient’s thigh is used. Autotransplantation is the use of autografts of thin, colon, stomach. Autoplastic surgeries are performed on the urinary tract: ureter, bladder. A very good auxiliary autoplastic material is the greater omentum. Autotransplantation may also include: replantation of a tooth, traumatically severed limbs or their distal segments: fingers, hands, feet. 10. Allotransplantation For allotransplantation, there are two sources of donor tissues and organs: a cadaver and a living volunteer donor. In modern surgery, skin allografts from both corpses and 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 the transfusion of blood as liquid tissue, which is widely used in medicine. 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 the collection of organs both from a corpse and from a living volunteer donor; preservation of cadaveric organs and tissues; overcoming tissue incompatibility. In the legislative support of allotransplantation, the criteria for death, in the presence of which organ retrieval is possible, legislation regulating the rules for organ and tissue retrieval, and the possibility of using allografts from living volunteer donors are of key importance. Preservation of donor organs and tissues allows transplantation material to be preserved and accumulated in tissue and organ banks for use for therapeutic purposes. The following main conservation methods are used. Hypothermia, i.e. preservation of an organ or tissue at a low temperature, at which a decrease in metabolic processes in tissues and a decrease in their need for oxygen occur. Freezing in a vacuum, i.e. lyophilization, which leads to an almost complete stop of metabolic processes while preserving cells and other morphological structures. Continuous normothermic perfusion of the bloodstream of the donor organ. At the same time, in the isolated organ normal metabolic processes by delivering the necessary oxygen to the organ nutrients and removal of metabolic products. Overcoming tissue incompatibility between donor and recipient tissues is essential for allotransplantation. This problem, first of all, relates 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 it are a very dynamic and rapidly developing area of clinical transplantology. 11. Xenotransplantation In modern surgery, transplantation of animal organs and tissues 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 prepared. 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, the problem of tissue incompatibility has not yet been resolved, clinical application xenografts are 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 and spleen of a pig - the animal that is genetically closest to humans. Attempts to transplant animal organs into humans have not yet led to lasting positive results. Nevertheless, this type of transplantation can be considered promising after solving the problems of tissue incompatibility. 12. Tooth transplantation: background and prospects Attempts at tooth transplantation 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 into the French princess instead of a tooth removed from her. In Russia, V. Antonevich defended his doctoral dissertation “On replantation and dental transplantation” in 1865. 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 man's constant desire to replace and restore lost teeth using a variety of materials of animal, human and mineral origin. Stones, including precious and precious metals, ivory and other materials, were used for implantation. The Thibaudie Museum at Harvard University in the United States displays a pre-Columbian human skull with precious stones implanted into the lower jaw, and the Peruvian Museum displays an Inca human skull with 32 implanted quartz and amethyst teeth. In Ancient Egypt, missing teeth were restored before mummification. Tooth transplantation was practiced from one person to another - the teeth of the poor were rearranged by the rich. These operations were performed by barbers (surgeons-hairdressers). In Egypt, Greece, India, Arab countries Dental implantation methods were used. In most cases, human teeth from slaves and animal teeth were used as implants, and the recipients were wealthy people. In America, the Indians used ground stones to replace a missing tooth. Attempts at dental transplantation were also made in the 20th century. But this method was not widely used for a number of reasons. Secondly, donors are needed. Thirdly, a bank is needed to store dental transplants. Fourthly, reliable sterilization of transplants is needed, guaranteeing the safety of such an operation, because When transplanting biological materials, there is a high risk of transmitting various infections. Fifthly, transplantation is very expensive. Sixthly, the results of dental transplantation ultimately turn out to be unsatisfactory. In most cases, either rejection of the transplanted teeth occurs, or their resorption as a result of an immune conflict. 13. Autologous tooth transplantation Autologous tooth transplantation - transplantation of a tooth into another alveolus. It is indicated when removing 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 surgical technique is the same as for replantation. Particular difficulties in this operation lie in 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 extracted and replanted teeth. Formation of the alveoli in accordance with the transplanted tooth often leads to additional trauma to the alveoli and removal of its periosteum, which adversely affects the healing process and is often complicated. 14. Tooth allotransplantation Tooth allotransplantation 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 case of the appearance (or presence from the moment of birth) of children of dental arch defects that impair the function of chewing and speech, are not amenable to orthodontic treatment and threaten to impair the growth and development of the alveolar processes, in particular: a) in the absence of a child with a shift or permanent bite two or more adjacent teeth or their rudiments, lost as a result of previous periodontitis or trauma, with the alveolar process preserved and the absence of pronounced destructive changes in it; b) in the absence of large molars lower jaw 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 conducted in this area by various authors, the following conclusions can be drawn: ) the most favorable time for transplanting tooth germs is the period when they already have basic structures without their pronounced differentiation and formation; ) taking the embryos from the donor and transplanting them into 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 recipient’s tissues over their entire surface, thereby ensuring strong fixation and nutrition of the sac; ) the rudiments must be isolated from oral infection with closed sutures or glue for the entire period of their engraftment and development. The experience of transplanting 16 tooth rudiments, 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). Crown eruption and root development were generally completed after 2-3 years, and after 4-5 years the teeth were functioning well. Encouraging results of dental allotransplantation in humans were obtained by V. S. Moroz: in 43 out of 53 patients, teeth were preserved for up to 5"/2 years; the minimum period of tooth functioning was 2 years. To achieve favorable results with tooth allotransplantation, it is necessary, in the author’s opinion, to observe the following conditions: ) ensure a tight fit of the gum to the root in accordance with the anatomical neck of the tooth; ) perform surgery only in the absence of atrophy of the gingival papillae; ) exclude traumatic impacts of the antagonist on the transplanted tooth; ) remove pathologically altered tissues surrounding the apex of the tooth in the recipient’s alveolus; According to A.P. Cherepennikova (1968), dental allotransplantation is indicated in three cases: ) with primary partial adentia as a result of the absence of rudiments permanent teeth; ) with fresh injuries of the jaws with loss of teeth; ) in the presence of teeth that must be removed due to the impossibility of saving them therapeutic methods. Thus, the presented data on allotransplantation of teeth and their rudiments indicate both a certain promise of the method and the need for its improvement. 15. Bone grafting Need for bone transplant Bone transplantation is often necessary in cases of complete edentulism, which is usually accompanied by severe bone resorption. At the moment of tooth extraction or dislocation, the process of incomplete bone remodeling begins, which inevitably leads to atrophy of the alveolar ridge. A bone graft retains its structure and function even if the number of viable cells decreases. The bone matrix is gradually filled with cells from adjacent tissues in a process known as slow replacement. This mechanism does not operate when transplanting skin or mucous membranes, so in these cases, maintaining the viability of the graft cells is of paramount importance for the success of the operation. Autogenous bone grafts The most frequently performed transplantation is bone tissue, which is used to eliminate defects caused by atrophy, trauma, tumor, as well as to correct congenital deformities. Elimination of bone defects is one of the most difficult tasks in maxillofacial surgery. Improvements in methods for obtaining, storing and using grafts have become possible thanks to a better understanding of the mechanisms of bone repair. Autogenous bone graft is so far 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, fibula, as well as fragments of the upper and lower jaw - mandibular symphysis, retromolar region and ramus; tubercle of the upper jaw, as well as hyperostosis of the bone. The great advantages of autogenous grafts over other bone grafts are determined by 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 involved in harvesting 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 the bone matrix. Due to the bone-inductive activity of the cells of the bone bed, new bone is formed, where the transplanted autograft plays the role of the bone skeleton. Subsequently, bone resorption and new formation occur simultaneously, which leads to the incorporation of a bone graft into the host bed. Autografts can be taken from cancellous or cortical bone or be combined. If they consist of cancellous bone, then after transplantation they experience rapid and more complete revascularization. Meanwhile, in autografts consisting of cortical bone, these processes occur more slowly, and, in addition, a significant part of the transplanted bone dies, and its replacement with new bone has a creeping nature. Conclusion Why implantation and not transplantation? A tooth transplant is the transplantation of a tooth or its germ that is taken from another person. Widespread this method was not successful for a variety of reasons. First, we need donors. Secondly, a bank is needed to store dental grafts. Thirdly, reliable sterilization of transplants is needed, guaranteeing the safety of such an operation, because When transplanting biological materials, there is a high risk of transmitting various infections. And finally, the results. They are disappointing. In most cases, either rejection of the transplanted teeth occurs, or their resorption as a result of an immune conflict. Implantation is the installation or insertion of a non-biological object. The object, which is non-biological in origin, can be made from biocompatible materials that are properly sterilized to ensure patient safety. Such materials rarely cause an immune conflict. Finally, implants can be mass produced and standardized. This allows the implantation method to be widely used and the necessary experience to be accumulated, which is the basis for achieving good treatment results. Bibliography Gluzman A.M., Matyash I.M.. Directory of surgical operations. Kyiv "Health", 1979 Kovanov V.V.. Experiment in surgery. Moscow "Young Guard", 1989 Moore F.. History of organ transplants. Moscow "Mir", 1987 Balin V.N., Aleksandrov N.M.. 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 V.V. Inflammatory diseases in the maxillofacial area in children. Moscow "Detstomizdat", 1998 Petrov S.V. General surgery. Moscow "GEOTAR-Media", 2010 Kozlov V.A. Dentistry: a textbook for medical universities and postgraduate training of specialists. St. Petersburg : SpetsLit, 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. Euro J Orthod, 1998 McCarthy C. Patel RR..Dental implants and onlay bone grafts. Int J Oral Implants, 2003
The problem of collecting organs and/or tissues from a donor is considered depending on whether the donor is a living or dead person.
Organ transplantation from a living donor is associated with harm to his health. In transplantology, compliance with the ethical principle of “do no harm” in cases where the donor is a living person turns out to be almost impossible. The doctor faces a contradiction between the moral principles of “do no harm” and “do good.”
On the one hand, an organ transplant (for example, a kidney) is to save the life of a person (recipient), i.e. is good for him. On the other hand, significant harm is caused to the health of the living donor of this organ, i.e. the principle of “do no harm” is violated and harm is caused. Therefore, in cases of living donation, it is always about the degree of benefit received and the degree of harm caused, and the rule always applies: the benefit received must exceed the harm caused.
The most common type of donation today is the removal of organs and (or) tissues from 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 permissibility 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 at the international, national and religious levels.
The motto of modern transplantology is: “When leaving 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 in force in a particular country for the collection of donor organs, on the other hand, to subjective reasons of an ethical, religious, moral and psychological nature.
Solving the problem of donor organ shortage.
The problem of the shortage of donor organs is being solved in various ways: organ donation is being promoted after the death of a person with lifetime consent for 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 tissue, creating artificial organs on based on the achievements of bioelectronics and nanotechnology.
The greatest problems arise in the field of solving scientific and medical problems associated with the danger of transferring various infections, viruses into the human body and the immunological incompatibility of animal organs and tissues with the human body. IN last years Pigs have come to the fore as donors for xenotransplantation; they have the closest set of chromosomes to humans, the structure of internal organs, reproduce quickly and actively, and have long been domestic animals. Advances 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 individual’s acceptance of an animal’s organ as one’s own, the awareness of one’s body as integral, truly human, even after transplantation of any animal organ into it.
The problem of donor organ distribution is relevant all over the world and exists as a problem of donor organ shortage. The allocation of donor organs in accordance with the principle of equity 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 health condition. The problem is that a patient, even in a very serious condition, may be at the top of this list and never wait for a life-saving operation. This is due to the fact that from the available volume of donor organs it is very difficult to select an organ suitable for a given patient due to immunological incompatibility. This problem is being solved to a certain extent by improving the methods of immunosuppressive therapy, but still remains very relevant.
Ensuring equal rights for patients occurs by following the following rules: the choice of recipient is carried out only in accordance with medical indications, taking into account the severity of the patient’s condition, his immunological and genetic characteristics; The priority of donor organs should not be determined by the identification of advantages of certain groups and special funding.
Ethical problems associated with the commercialization of transplantation are associated with the fact that human organs become a commodity, and in conditions of a general shortage of donor organs, a scarce and very expensive commodity.
According to Russian law, the purchase and sale of organs is prohibited. Article 15 establishes the inadmissibility of the sale of human organs and (or) tissues. It is considered absolutely unacceptable to create a market for donor organs and tissues and make a profit from trading them. However, it is well known that in accordance with the economic law “demand creates supply,” there is a “black” market for donor organs and tissues. In this case, donor-sellers are living people who, for various (mostly material) reasons, decide to sell one of their organs. Mainly one of the paired organs of the human body is sold, among which most in demand kidneys serve. Commercialization contradicts the highest humanistic idea of transplantology: death serves to prolong life.
In solving these problems special meaning acquires compliance with the ethical principles of informed voluntary consent, non-maleficence and social justice. These principles form the basis of all international and national ethical and legal documents regulating the activities of medical workers in the field of transplantation of human organs and tissues.
1. Problems of transplantology at the present stage
The successes of transplantology have shown that a new, extremely promising opportunity has opened up for humanity to treat patients who were previously considered doomed. At the same time, a whole range of legal and ethical problems arose that required the joint efforts of specialists in the field of medicine, law, ethics, psychology and other disciplines to be resolved. These problems cannot be considered solved if the approaches and recommendations developed by experts do not receive public recognition and enjoy public trust.
Organ transplantation has not become a widespread practice in our country. medical care not at all because the need for it is small. The reasons are different. The most important and, alas, the most prosaic - transplantation of any organ results in an amount that, I suspect, our average-income person cannot accumulate in his entire life. The state is obliged to provide this expensive treatment. But we know its capabilities.
Problem number two of modern transplantology is the shortage of donor organs, in relation to Russian reality. It seems at first glance that her simplest solution is to use the organs of accidentally deceased healthy people. And although, sadly, hundreds of people die from injuries every day in our country alone, ensuring organ donation is not an easy matter. Again, for many reasons: moral, religious, purely organizational.
IN different countries There are different approaches to the procurement of donor organs around the world. In China, it is legal to take them from the corpses of executed people. This is unacceptable for Russia. We have a moratorium on the death penalty, and even before it was announced, the secrecy that shrouded this action did not allow transplantologists to see it. The acts of donating organs adopted in many countries seem much nicer and more promising than the Chinese experience. People who are young and in good health bequeath, in case they unexpectedly die, their organs to those whose lives they can save. Pope John Paul II called this kind of gift a micro-reproduction of the feat of Christ. If such acts were adopted in Russia, the collection of organs for direct donation would be much simpler, and we would be able to help an incomparably larger number of seriously ill patients.
Several years ago in Moscow, on the basis of one of the city hospitals, the only center for organ procurement in the entire metropolis was created. And if the collection of kidneys from corpses was carried out, then the removal of hearts was very bad. The Research Institute of Cardiology (now in Russia it has a monopoly on heart 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 Moscow center practically does not deal with liver and lung retrieval, which requires the highest qualifications of transplantologists and is associated with strict time restrictions, 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 coincide. But this is also not a guarantee of engraftment of a transplanted heart or kidney, and therefore another problem is overcoming the risk of organ rejection. There are no unified means to prevent the rejection process yet. The world is constantly working on new immunosuppressants. And each one is better than the previous one, and each one is initially received with a bang. But as they begin to work with him, the delight subsides. All existing drugs in this series are still imperfect in different ways, all have side effects, all reduce the overall immunological response, in turn causing severe post-transplant complications. infectious lesions, and some also hit the kidneys, liver, and increase blood pressure. We have to abandon monoimmunosuppressive therapy. Have to combine different drugs, maneuver the doses of each, make compromises.
2. Ethical problems of transplantation
Ethical issues in transplantation vary significantly depending on whether organs are being harvested for transplantation from a living person or from a deceased person.
Transplantation from living donors. Kidney transplantation is the first area of transplantology that has found a place in practical medicine. Currently, this is a rapidly developing area of medical care for patients with irreversibly impaired kidney function throughout the world. Kidney transplants have not only saved hundreds of thousands of patients from death, but also provided them with a high quality of life.
In addition to the kidney, a lobe of the liver is transplanted from a living donor, Bone marrow etc., which in many cases is also a life-saving treatment method for the patient. However, this arises whole line difficult moral problems:
1. organ transplantation from a living donor involves serious risks for the latter;
2. the transplant must take place with informed, conscious, voluntary consent;
3. The transplant must be ensured by observing the principle of confidentiality.
Organ donation of a deceased person. The use of a human corpse as a source of organ transplantation raises a range of difficult moral issues. All world religions require careful and respectful treatment of the body of a deceased person.
It is believed that the rights of the individual, who has lost the right to control the fate of remains that are no longer useful to him, are outweighed by the obvious benefit to society in the form of potential recipients, whose lives can be saved as a result of the transplant.
Such practices and such attitudes are considered morally deficient from a human rights perspective.
The use of organs and tissues not only of humans, but also of animals – xenotransplantation – is becoming increasingly widespread. Primates are the closest genetically to humans. Evolutionary proximity increases the risk of transmission and subsequent spread to humans viral infections existing in primates. There is an assumption that AIDS arose as a result of the entry of the monkey immunodeficiency virus into the human body.
Universal organ donors are being created for humans and on the basis of certain breeds of pigs, the physiological and anatomical structure of whose internal organs is quite close to that of humans. But by transplanting organs from, for example, pigs into a person, we also risk simultaneously transmitting diseases such as brucellosis, swine flu and a number of other infections – both observed and not observed under normal conditions in humans. The latter is especially dangerous, since in human body no evolutionarily developed defense mechanisms to fight them.
3. Further development of transplantology
In any case, transplantology is a rapidly developing field of medicine. And if so, we will have to look for other options for replacing used human organs. One of them is the further improvement of artificial organs. Already today, chronic hemodialysis can support a person’s life for a long time, sometimes for 10-15 years. And it is possible that new artificial kidney models that researchers are working on will make it possible to extend this period even further. And no problems with rejection! Only permanent connection of the patient to the hemodialysis center. Long-term treatment An artificial kidney is to some extent an alternative to a donor one, although among specialists there are more supporters of transplantation. After all, any most perfect man-made mechanism worse than that, which was invented by nature itself. In addition, long-term hemodialysis is more expensive than a kidney transplant.
The artificial heart also has a great future. Already today they are working with left ventricles and hearts of their own design in many research institutes. These are precision mechanisms made from special polymer materials and high-quality metal alloys. Connected to patients, they act as continuously running pumps that pump blood and allow the patient to wait donor heart. Artificial ventricles are often used as a “bridge” to subsequent transplantation - they are small in volume and their connection is less traumatic.
Conclusion
Transplantology is undoubtedly an exclusive area of modern medicine. The number of people living with foreign organs is growing. In developed countries of the world, transplants are practiced everywhere. The liver, kidneys, heart, lungs, intestines, parathyroid and pancreas, cornea, skin, bones, joints, entire limbs, etc., even brain cells are transplanted. And despite the fact that organ transplantation is performed incomparably less often than, say, operations on the abdominal cavity, and is practically one-off in nature, in its essence - in its drama, novelty, sometimes bordering on fantasy, transplantology is something everyone, even the doctors themselves, care about. causes falling interest. According to experts, this is only a running start before the decisive leap that will occur in the coming years.
I would like to believe that the beginning of the coming century will finally be crowned with the creation of effective selective immunosuppressants that specifically target only the immune response of the transplanted organ. I would like to believe that over time the key to ensuring the body’s full tolerance to a transplanted kidney or heart will be found.
However, discussions about the timeliness, feasibility, and ethics of transplantation do not subside.
Of course, experimentation is necessary in the interests of industry development, but when and to what extent?
The solution to the question of the boundaries between experiment and treatment has a purely practical significance. As operations become more complex, their cost increases, while the results leave much to be desired, and the scale of use of transplantations remains limited due to the shortage of donor organs. In any, even the most favorable case, organ transplantation is a salvation for few. Under these conditions, are gigantic investments in this particular sector of healthcare justified? Wouldn't it be more expedient, and ultimately more ethical, to develop methods of treating and preventing diseases of the heart, liver, and kidneys that can be used more widely by patients?
Bibliography
1. Nursing theory. S.I. Dvoinikov M. 2002
2. Nursing. G.P.Kotelnikov."Phoenix" Rostov-on-Don 2006
3. Campbell A. “Medical Ethics.” M. "GEOTAR-MED" 2004
4. Yarovinsky M.Ya. lectures on the course of medical ethics - M. 2001
5. Yarovinsky M.Ya. "Medical ethics". M. "Medicine" 2004
6. Law of the Russian Federation “On Transplantation of Human Organs and Tissues” - M.1992
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