Transplant surgery entails the removal of a viable organ from a donor and placing it into another person whose own organ has been damaged beyond repair or failed. This surgery is usually life-saving. Thanks to advances over the years with regard to immunosuppression and surgical techniques, it is now one of the most effective means of treating a number of conditions.
Despite these advances, there is still significant risks involved for the recipient. There are over 2500 organ transplants performed annually in the UK, where nearly 9 out of every 10 transplanted organs remain viable one year postoperatively.
The liver is one of the most important organs in the body, and has functions ranging from the metabolisms of toxins and drugs to the synthesis of enzymes and proteins. Without a liver, survival is impossible, and a patient with a diseased or failing liver which cannot be cured with other medical interventions requires a liver transplant.
Acute failure of the liver, which is also referred to as fulminant hepatic failure, happens in the setting of previous normal liver function and sudden deterioration. The causes of fulminant liver failure are many, but include viral infections, drug overdoses/ idiosyncratic reactions and the ingestion of toxic mushrooms.
Liver failure over a longer period of time, also known as chronic liver failure, may arise due to decades of hepatic insults. This is most commonly the case in alcoholics, whose livers develop scarring or cirrhosis. Other causes of chronic hepatic failure include autoimmune, viral, metabolic, oncological or genetic conditions causing long-term hepatic injury.
Candidates for transplantation are those who are most likely to survive following the operation and comply with requirements, such as medications, frequent check-ups and lifestyle changes, like alcohol abstinence. Patients are placed on a waiting list and consideration is given to the urgency of the recipient’s need.
The Model for End-stage Liver Disease or MELD score is a scoring system used to predict the risk of death due to chronic liver disease. It is determined by total bilirubin, prothrombin time and creatinine clearance. Donors may be brain- or cardiac-dead patients, in which case the entire liver is removed and transplanted. Donors may also be living donors as well, and in such cases the natural anatomical segmentation of the liver allows persons to live even with parts of the liver removed. Such livers can grow back in both the donor and recipient.
To prevent rejection, which is a grave risk with nearly all transplants, patients are placed on immunosuppressive drugs. Generally, the prognosis following transplant is good with a 73% patient survival rate after 5 years.
The majority of candidates for cardiac transplants are those who have end-stage heart disease with severe decompensation. Causes of this condition include viral infections, coronary artery disease and genetic disorders. In some instances, although rare, the heart may be transplanted along with the lungs. Like liver transplants, there are also waiting lists for heart transplants and the urgency for the transplantation is taken into account.
During the surgery the patient’s chest is opened up and the circulatory system is connected to a heart and lung bypass machine, which allows blood to keep being pumped around the body. Once the new, healthy heart is in place, the blood vessels are reconnected to it.
Following the procedure, patients are hospitalized for sometimes up to a month to allow for recovery. It is necessary that they follow good hygiene to minimize the risk of infection. More importantly, they should have routine vaccinations and make lifestyle changes to reduce the risk of their new hearts failing as well. The one-year survival rate is about 85%.
Some of the risks involved include failure of the new heart to function, which is the most common cause of death within a month of transplant. There is also the risk of rejection and therefore, patients will need to take life-long immunosuppressive drugs.
VIDEO Renal transplantation
The kidneys are a pair of organs in our abdominal cavity, necessary for maintaining life. Unfortunately, these pivotal organs may also be the victims of insults, such as diabetes, glomerulonephritis, high blood pressure and other genetic disorders, which may cause their failure. Transplant is necessary in end-stage renal disease. To buy the patient time until the transplant, there are medical means, such as dialysis to filter the blood. Eventually, the transplant surgery is conducted, which may take up to 4 hours.
Compared to its dysfunctional predecessor, the new kidney is placed in a different anatomical position, which is in the lower abdomen. This surgery is referred to as a heterotopic transplant. In contrast, the heart and liver undergo orthotopic transplantations (i.e. placed in original anatomical positions). The dysfunctional kidneys are typically not removed unless they cause significant pathology. Complications include infection, bleeding and rejection. Patients are carefully monitored following the surgery and require lifelong immunosuppressive therapy.
Reviewed by Liji Thomas, MD References
https://www.niddk.nih.gov/health-information/kidney-disease/kidney-failure/kidney-transplant Further Reading