Liver Transplantation : Overview

Introduction:

A liver transplant is a surgical procedure that removes a liver that no longer functions properly (liver failure) & replaces it with a healthy liver from a deceased donor or a portion of a healthy liver from a living donor.

Liver is largest internal organ & performs several critical functions, including:

    • Processing nutrients, medications & hormone
    • Producing bile, which helps the body absorb fats, cholesterol & fat-soluble vitamins
    • Making proteins that help the blood clot
    • Removing bacteria & toxins from the blood
    • Preventing infection & regulating immune responses

Liver transplant is usually reserved as a treatment option for people who have significant complications due to end-stage chronic liver disease. Liver transplant may also be a treatment option in rare cases of sudden failure of a previously healthy liver.

 

The number of people waiting for a liver transplant greatly exceeds the number of available deceased-donor livers.

 

Living-donor liver transplant is an alternative to waiting for a deceased-donor liver to become available. Living-donor liver transplant is possible because the human liver regenerates & returns to its normal size shortly after surgical removal of part of the organ.

Indications of liver transplantation & causes of liver failure:

Liver transplant is a treatment option for people with liver failure whose condition can’t be controlled with other treatments & for some people with liver cancer.

 

Liver failure may happen quickly or over a long period of time. Liver failure that occurs quickly, in a matter of weeks, is called acute liver failure. Acute liver failure is an uncommon condition that is usually the result of complications from certain medications.

 

Although a liver transplant may treat acute liver failure, it is more often used to treat chronic liver failure. Chronic liver failure occurs slowly over months & years.

 

Chronic liver failure may be caused by a variety of conditions. The most common cause of chronic liver failure is scarring of the liver (cirrhosis). When cirrhosis occurs, scar tissue replaces normal liver tissue & causes the liver to not function properly. Cirrhosis is the most frequent reason for a liver transplant.

Major causes of cirrhosis leading to liver failure and liver transplant include:

  • Hepatitis B & C
  • Alcoholic liver disease, which causes damage to the liver due to excessive alcohol consumption
  • Non-alcoholic fatty liver disease, a condition in which fat builds up in the liver, causing inflammation or liver cell damage
  • Genetic diseases affecting the liver, including hemochromatosis, which causes excessive iron build-up in the liver, & Wilson’s disease, which causes excessive copper build-up in the liver
  • Diseases that affect the bile ducts (the tubes that carry bile away from the liver), such as primary biliary cirrhosis, primary sclerosing cholangitis and biliary atresia. Biliary atresia is the most common reason for liver transplant among children
  •  Liver transplant may also treat certain cancers that originate in the liver

Risks & complications:

Liver transplant surgery carries a risk of significant complications. There are risks associated with the procedure itself as well as with the drugs necessary to prevent rejection of the donor liver after the transplant.

Risks associated with the procedure include:

    • Bile duct complications, including bile duct leaks or shrinking of the bile ducts

    • Bleeding

    •  Blood clots

    • Failure of donated liver

    • Infection

    • Rejection of donated liver

    • Mental confusion or seizures

    •  Long-term complications may also include recurrence of liver disease in     the transplanted liver

Anti-Rejection medications (immunosuppressant) side effects:

Anti-Rejection medications (immunosuppressant) side effects:

    • Bone thinning
    • Diabetes
    • Diarrhoea
    • Headaches
    • High blood pressure
    • High cholesterol

Because anti-rejection drugs work by suppressing the immune system, they also increase risk of infection. Patients might have to take medications which will help to fight infections.

The goals of the evaluation process for liver transplant are to determine whether patient:

    • Are healthy enough to have surgery & tolerate lifelong post-transplant medications
    • Have any medical conditions that would interfere with transplant success
    • Are willing & able to take medications as directed & follow the suggestions of the transplant team

Specific tests, procedures & consultations patient may undergo include:

    • Laboratory tests, such as blood and urine tests to assess the health of other organs, including liver
    • Imaging tests, such as an ultrasound of liver
    • Heart tests to determine the health of cardiovascular system
    •  A general health exam, including routine cancer screening tests, to evaluate overall health & to check for any other illnesses that may impact the success of transplant

Evaluation may also include:

    • Nutrition counselling with dietitians who assess diet & make recommendations on how to plan healthy meals before and after transplant
    • Psychological evaluation to assess & treat any underlying issues, such as depression or anxiety, & determine whether patient fully understand the risks of a liver transplant
    • Meetings with social workers who assess support network to determine whether patient have friends or family to take care for after transplant
    • Addiction counselling to help people who are struggling with how to quit alcohol, drug or tobacco
    • Financial counselling to help patient understand the cost of a transplant & post-transplant care & to determine what costs are covered by insurance

Results of patient’s liver function tests & other factors are used to assess the severity of patient’s illness, how urgently patients need a transplant & patients placed on the liver transplant waiting list.

 

Transplant waiting list priority is determined by two scoring systems called Model for End-Stage Liver Disease (MELD) for adults & Paediatric End-Stage Liver Disease (PELD) for children younger than age 12.

 

Specific formula is used to determine MELD scores, which can range from 6 to 40. The scores estimate the risk of death within 90 days without a transplant. A high MELD score indicates the urgent need of a transplant.

 

As deceased-donor organs become available, they are allocated according to MELD scores and classified by blood type. People with higher MELD scores are generally offered donated livers first. Time spent on the liver transplant waiting list is used to break ties among people with the same MELD scores & blood type.

 

Some liver conditions, such as liver cancer, may not result in a person getting a high MELD score. The transplant center can request additional MELD points for people with specific diseases if they meet defined exception criteria.

 

In addition, adults with acute liver failure are exempted from the MELD-based donor organ prioritization system & may be placed higher on the transplant waiting list according to the severity of their disease.