Transplant surgery is the surgical removal of an organ(s), tissue, or blood products from a donor and surgically placing or infusing them into a recipient.
Transplant surgery is a treatment option for diseases or conditions that have not improved with other medical treatments and have led to organ failure or injury. Transplant surgery is generally reserved for people with end-stage disease who have no other options.
The decision to perform transplant surgery is based on the patient's age, general physical condition, diagnosis and stage of the disease. Transplant surgery is not recommended for patients who have liver, lung, or kidney problems; poor leg circulation; cancer; or chronic infections.
Organ Donors :-
Organ donors are classified as living donors or cadaveric (non-living) donors. All donors are carefully screened to make sure there is a suitable blood type match and to prevent any transmissible diseases or other complications.
LIVING DONORS : Living donors may be family members or biologically unrelated to the recipient Living donors must be physically fit, in good general health, and have no existing disorders such as diabetes, high blood pressure, cancer, kidney disease, or heart disease.
Single kidneys: There is little risk in living with one kidney because the remaining kidney compensates for and performs the work of both.
Liver: Living donors can donate segments of the liver because the organ can regenerate and regain full function.
Lung: Living donors can donate lobes of the lung although lung tissue does not regenerate.
Pancreas: Living donors can donate a portion of the pancreas even though the gland does not regenerate.
Living donor transplants are often more successful than cadaveric donor transplants because there is a better tissue match between the donor and recipient. The living donor's medical expenses are usually covered by the organ recipient's insurance company, but the amount of coverage may vary.
CADAVERIC OR DECEASED DONORS : Organs from cadaveric donors come from people who have recently died and have willed their organs before death by signing an organ donor card, or are brain-dead. The donor's family must give permission for organ donation at the time of death or diagnosis of brain death. Cadaveric donors may be young adults with traumatic head injuries, or older adults suffering from a stroke. The majority of deceased donors are older than the general population.
Transplant Procedures :-
ORGAN HARVESTING : Harvesting refers to the process of removing cells or tissues from the donor and preserving them until they are transplanted. If the donor is deceased, the organ or tissues are harvested in a sterile operating room. They are packed carefully for transportation and delivered to the recipient via ambulance, helicopter or airplane. Organs from deceased donors should be transplanted within a few hours of harvesting. After the recipient is notified that an organ has become available, he or she should not eat or drink anything.
When the organ is harvested from a living donor, the recipient's transplant surgery follows immediately after the donor's surgery. The recipient and the donor should not eat or drink anything after midnight the evening before the scheduled operation.
PREOPERATIVE PROCEDURES : After arriving at the hospital, the recipient will have a complete physical and such other tests as a chest x ray, blood tests, and an electrocardiogram (EKG) to evaluate his or her fitness for surgery. If the recipient has an infection or major medical problem, or if the donor organ is found to be unacceptable, the operation will be canceled.
The recipient will be prepared for surgery by having the incision site shaved and cleansed. An intravenous tube (IV) will be placed in the arm to deliver medications and fluids, and a sedative will be given to help the patient relax.
TRANSPLANT SURGERY : After the patient has been brought to the operating room, the anesthesiologist will administer a general anesthetic. A central venous catheter may be placed in a vein in the patient's arm or groin. A breathing tube will be placed in the patient's throat. The breathing tube is attached to a mechanical ventilator that expands the lungs during surgery.
The patient will then be connected to a heart-lung bypass machine, also called a cardiopulmonary bypass pump, which takes over for the heart and lungs during the surgery. The heart-lung machine removes carbon dioxide from the blood and replaces it with oxygen. A tube is inserted into the patient's aorta to carry the oxygenated blood from the bypass machine back to the heart for circulation to the body. A nasogastric tube is placed to drain stomach secretions, and a urinary catheter is inserted to drain urine during the surgery.
The surgeon carefully removes the diseased organ and replaces it with the donor organ. The blood vessels of the donated organ are connected to the patient's blood vessels, allowing blood to flow through the new organ.
Types of Transplants :-
Autograft : A transplant of tissue from one to oneself. Sometimes this is done with surplus tissue, or tissue that can regenerate, or tissues more desperately needed elsewhere (examples include skin grafts, vein extraction for CABG, etc.) Sometimes this is done to remove the tissue and then treat it or the person, before returning it (examples include stem-cell autograft and storing blood in advance of surgery).
Allograft : An allograft is a transplanted organ or tissue from a genetically non-identical member of the same species. Most human tissue and organ transplants are allografts.
Isograft : A subset of allografts in which organs or tissues are transplanted from a donor to a genetically identical recipient (such as an identical twin). Isografts are differentiated from other types of transplants because while they are anatomically identical to allografts, they are closer to autografts in terms of the recipient's immune response.
Xenograft and Xenotransplantion : A transplant of organs or tissue from one species to another. Xenotransplantion is often an extremely dangerous type of transplant. Examples include porcine heart valves, which are quite common and successful, a baboon-to-human heart (failed), and piscine-primate (fish to non-human primate) islet (i.e. pancreatic or insular tissue), the latter's research study directed for potential human use if successful. See: xenotransplantation.
Split Transplants : Sometimes, a deceased-donor organ (specifically the liver) may be divided between two recipients, especially an adult and a child. This is uncommon, as the outcomes are worse for both patients than had they received the whole organ.
Domino Transplants : This operation is usually performed for cystic fibrosis as both lungs need to be replaced and it is a technically easier operation to replace the heart and lungs en bloc. As the recipient's native heart is usually healthy, this can then itself be transplanted into someone needing a heart transplant. That term is also used for a special form of liver transplant, in which the recipient suffers from familial amyloidotic polyneuropathy in which the liver (slowly) produces a protein that damages other organs; their liver can be transplanted into an older patient who is likely to die from other causes before a problem arises.