The United Network for Organ Sharing (UNOS) is the national organization in charge of administering and allocating organs from deceased donors. They use four different criteria to rank the priority of potential organ recipients for liver transplants:
- Urgency of condition – Within each blood type list, people are ranked by urgency of medical condition. This is indicated in general by their MELD score.
- Location – Available organs are allocated within their local region. The United States is divided into 11 regions, each with its own supply and demand. Lahey Hospital & Medical Center is part of UNOS region 1, which includes most of New England.
- Blood type – Within each region, the liver transplant waiting list is divided into four different lists separated by blood group: O, A, B, and AB. The + or- after a blood type is not a factor in liver transplantation so for example, an O+ person can donate to an O- recipient.
- Liver size – Your body size is another consideration in liver allocation. The donor liver has to have an adequate volume for the transplant to be a success. If you are a large person, a small liver will not provide you with sufficient function.
UNOS forbids organ allocation based on any other factors, such as age, sex, race, or socioeconomic status. It is also illegal to purchase a liver or any other organ.
About the MELD Score in Liver Transplantation
In 2002, UNOS implemented a nationwide system for prioritizing patients for liver transplantation. It is called the Model for End Stage Liver Disease, or MELD, and it is based on a very accurate statistical formula that predicts which people are most likely to die in the near future from their liver disease.
The MELD score is determined by using the results of three blood tests (bilirubin, INR, and creatinine) to determine the severity of a person’s liver disease. The score ranges from 6 (normal liver function) to 40 (severe liver disease).
While on the waiting list, each person’s MELD score must be updated according to a schedule determined by UNOS. The score may go up or down over time, depending on the status of the patient’s liver disease. A MELD score may be reassessed weekly, monthly, every three months or annually. The higher the score, the more frequently it will need to be reassessed.
Time spent on the waiting list has not been a factor in liver allocation since the MELD score was introduced. For example, an ill patient with a very high MELD score may be listed and get a liver quickly, “passing” someone who has been on the list for a longer time but has a lower MELD score.
Waiting Time for Liver Transplantation
It is impossible to predict when a liver will become available for transplantation. Patients with higher MELD scores receive liver offers more quickly than patients with lower MELD scores. In general, patients with blood type O or B have the longest wait times, while those with blood type A or AB generally wait a shorter time.
Staying Active on the Liver Transplant Waiting List
In order to remain active on the liver transplant waiting list, it is essential that you understand and fulfill certain responsibilities. These include but are not limited to:
- Keeping all scheduled appointments
- Obtaining laboratory and radiology testing according to the schedule you will be given. This schedule is a UNOS regulation and it is extremely important that you adhere to it. If you do not, you will become ineligible for a liver transplant
- Random drug and alcohol screening
Communication with Our Transplant Center
It is imperative that you or a member of your family contact your liver transplant coordinator or another member of the transplant team regarding any of the following situations:
- Admission to another hospital
- A visit to the Emergency Room
- Diagnosis of an infection of any type
- Any changes in contact information, including address and phone numbers for you and/or your primary contact person
- Any changes in your insurance coverage, including prescription plans
- Your inability to keep any scheduled appointments at the transplant center
It is permissible for patients to be listed at more than one transplant center simultaneously, but certain restrictions apply. UNOS regulations allow you to be listed at more than one transplant center as long as the two centers are not in the same geographic region.