Before any transplantation procedure strict medical requirements must be met, such as:

Health conditions of the donor and recipient:

Only organs and tissues that do not cause irreversible health problems when removed from a donor can be collected. In addition, transplanted organs must be intact, healthy, and physiologically functioning properly.

Before the surgical procedure, the recipient’s health must be stable.

Compatibility:

Before the operation, the immune system data of the donor and recipient are carefully analyzed and compared to determine compatibility in order to prevent a rejection reaction and other potential complications. Blood group compatibility according to the AB0 system is essential when transplanting organs. Also acceptable is incompatibility with the AB0 standard. When selecting a donor, HLA (leucocyte antigens, also known as histocompatibility antigens) antigen compatibility is regarded as decisive.

Following transplantation types are distinguished:

• Autotransplantation, also known as autologous transplantation, is a transplant in which both the donor and recipient are the same individual. In cases of severe burns, it is autotransplantation when skin from intact areas is transplanted to damaged areas. Following high-dose antitumor chemotherapy treatments for leukemia, lymphoma, and other malignant tumors, autotransplantation can also be performed with bone marrow or transplant stem cells.
• Isotransplantation, also known as isogenic transplantation, occurs when the donor is the recipient’s genetic and immunological twin. Such procedures are uncommon due to the rarity of identical twins and the prevalence of similar chronic diseases among twins.
• Allotransplantation, or homotransplantation, occurs when the donor and recipient of a human transplant are genetically and immunologically distinct. This is the case for the vast majority of human-to-human transplants. It is possible to obtain organs from the recipient’s family members, but they can also be obtained from other sources. This transplants can be performed including by deceased donors. All age groups should view themselves as potential donors. When a person dies, their medical history and age are reviewed to determine their potential as a donor. The medical appropriateness for donation is determined by the organ procurement organization.
• Xenotransplantation, also known as inter-species transplantation, is the transplantation of organs from one species to another, such as an animal to a human. This method has only been used in a very limited capacity, but it can involve the use of ‘xeno skins’ (i.e. animal skins, such as those of a pig) or cell cultures derived from the pancreas -cells of a pig.

Еach transplant procedure is always preceded by a waiting time and a series of bureaucratic, medical and legal checks. Details vary depending on the state where the transplant is performed.

The transplant surgeon always makes the ultimate determination on the compatibility of the donor and intended recipient. The organs are recovered in the same operating room as the donor is being cared for. The coordinator for transplants supervises the arrival and departure of the surgical recovery team. The recovery team includes of surgeons, nurses, a coordinator for organ transplants, and an organ preservation technician. Shortly prior to being extracted from the donor, each organ is flushed with a specially prepared ice-cold preservation solution containing electrolytes and nutrients. The organs are subsequently packed in sterile containers with wet ice and transferred to the transplant center of the recipient. It is essential that organs be transported as rapidly as possible from the donor to the intended recipient. After removal from the donor, hearts and lungs must be replaced within four hours. The liver can be kept for 12 to 18 hours, the pancreas for 8 to 12 hours, the intestines for roughly 8 hours, and the kidneys for 24 to 48 hours.

Organ transplantation is the most effective treatment for permanent and terminal organ failure. The clinical significance of solid organ transplants may be measured by their effect on patient survival, the decrease of comorbidities, the enhancement of labor life, and the global quality of life of the transplant population.

Heart

Recipients of a successful heart transplant have more energy, a higher quality of life, and the benefit of living longer. Adults have an overall survival rate of over 85 percent after one year and over 70 percent after five years.

Kidney

Individuals who receive a kidney transplant not only see an increase in their quality of life, but they will also no longer require dialysis treatments or suffer from the adverse effects of dialysis, such as nausea, vomiting, and low blood pressure. Most kidney transplants extend recipients’ lifespan by an average of 12 to 15 years.

Liver

Because to the huge number of tasks the liver is responsible for, a liver donation can rescue individuals from chronic illnesses such as hepatitis or drug or alcohol-induced damage. A given liver can occasionally be divided between two recipients, meaning that one liver donor has the potential to save the lives of two individuals. Seventy-five percent of liver transplant recipients survive at least five years.

Lung

Those with end-stage lung failure, cystic fibrosis, pulmonary hypertension, emphysema, or pulmonary fibrosis may have no further therapy options. Often, two lungs from a donor are transplanted into a single recipient.

Rejection is an inflammatory reaction to a transplanted organ caused by the recipient’s immune system’s negative response to the donor’s transplantation antigens.

Despite all efforts to find the genetically most compatible donor for each recipient, it is impossible to achieve a perfect genotype match. Consequently, recipients may experience a rejection reaction following surgery. In autotransplantation procedures, the risk of a rejection reaction is low, and the greater the compatibility between the recipient and donor, the less frequently rejection occurs.

To prevent organ rejection after transplantation, the recipient undergoes pharmacological/medical immunosuppression to reduce the effectiveness of the immune system. In uncomplicated cases, this only necessitates the administration of relatively small doses of medication on a specific schedule. However, if graft-versus-host disease progresses, the dosage or combination of immunosuppressive agents will be significantly increased.

Patients should remember that immunosuppression significantly increases the risk of postoperative infections-related complications. The medications will suppress the body’s natural rejection response. The recipient will likely remain under the care of a physician for the remainder of their lives.