Types of transplants
In a kidney transplantation, a donor kidney is implanted into a patient with kidney disease. This is necessary if both kidneys of the patient fail. This can be the case due to various diseases.
These include diabetes mellitus, glomerulonephritis, shrunken or cystic kidneys, severe tissue damage due to urinary retention or nephrosclerosis, in which the kidneys are damaged by high blood pressure. If the kidneys fail, the patient can first be connected to dialysis. This is a machine that takes over the kidney function.
However, regular connection to dialysis entails considerable restrictions in everyday life, which is why a kidney transplant is often the only promising option. A kidney transplant can be performed as a living donation or as a post-mortem donation. Since a healthy person has two functioning kidneys, he or she can donate one of them without being restricted.
A kidney as a live transplant has proven to be significantly longer lasting and functional than transplants from deceased people. However, most transplants are from deceased people. On average, the transplanted kidney loses its function after about 15 years and a new transplant is necessary.
After the operation, the placed bladder catheter must remain in place for about 5 to 6 days to drain the urine so that the surgical sutures on the bladder can heal. If the transplanted kidney is not immediately functional and produces urine, dialysis therapy may be necessary for a few days. Liver transplantation is necessary in patients with chronic or acute liver failure.
The most common reason why patients are put on the waiting list for a donor liver is alcoholic cirrhosis of the liver. However, liver cirrhosis can also be caused by medication or hepatitis and a transplant may be necessary. Other reasons for a liver transplantation are tumors, vascular diseases or congenital metabolic diseases such as hemochromatosis or others.
The majority of donor organs come from deceased people. However, it is also possible that only a part of the liver is transplanted, which is taken from a living donor. These partial liver donations are mainly found in parents who donate it to their child.
It is also possible to divide the organ in the case of a postmortem donor liver. The larger part is then implanted into an adult, the smaller part into a child. This procedure is called split liver.
The 10-year survival rate of a patient who has received a donor liver is approximately 70%. In order to be placed on the waiting list for a donor lung, there must be a definitive lung failure, which requires lifelong respiratory failure treatment. In most cases, it is chronic obstructive pulmonary disease that leads to such organ failure.
However, other diseases, such as cystic fibrosis, pulmonary fibrosis, an inflammation of the alveoli (alveolitis), sarcoidosis or high blood pressure in the pulmonary circulation (pulmonary hypertension) can also be reasons for a lung transplantation. A lung transplant can be performed either on one or both sides. In some cases, not only the lung but also the function of the heart is affected.
In such cases, a combined heart–lung transplantation is necessary. Since very few donor lungs are available, the criteria for awarding these are correspondingly strict. Patients must not have any other serious diseases and must be younger than 60 years of age in the case of unilateral transplantation and younger than 50 years of age in the case of bilateral transplantation in order to be considered as recipients.
Furthermore, life expectancy must be less than 18 months. The life expectancy after a successfully transplanted lung is about 5 to 6 years after the operation. The first two to three weeks after the operation are very critical and rejection reactions often occur.
Heart transplantation is considered when the patient’s heart is severely impaired in its functional ability and cannot be improved by therapeutic measures. The majority of heart transplantations are performed in patients with heart muscle weakness (cardiac insufficiency) due to inflammation of the heart muscle (cardiomyopathy). In rare cases, heart valve defects or congenital heart defects may also make heart transplantation necessary.Only those deceased persons who did not suffer from a heart disease are admitted as donors.
In addition, the size of the donor and recipient heart must match. Since the waiting period for finding a suitable donor heart is often very long, heart pumps can be used to bridge the gap by supporting the pumping function of the heart muscle. In some cases, not only the patient’s heart but also the lungs are irreversibly damaged.
In such cases, a combined heart-lung transplantation must be performed. Rejection reactions often occur after the operation. Already in the first year after the operation, on average every 10th patient with a donor heart dies.
In order to be approved for a pancreas transplantation, the patient must suffer from type I diabetes. The pancreas must no longer produce insulin and the patient must be on dialysis to get on the waiting list for a pancreas donation. Since type I diabetes often causes vascular damage that mainly damages the kidneys, a combined pancreas-kidney transplantation may be necessary in cases of complete kidney failure.
