Transplantation Process

The United States has the most effective national donation and transplantation network in the world. Over the years, an efficient, equitable system for the sharing of organs has been developed by medical leaders. In 1984, the National Organ Transplant Act mandated the establishment of the National Organ Procurement and Transplantation Network (OPTN) and the U.S. Scientific Registry of Transplant Recipients. These organizations are administered by the United Network for Organ Sharing (UNOS), a private, non-profit entity.

Patients are placed on a national list

People requiring an organ transplant suffer from end-stage failure of a vital organ. This means that without a transplant or other significant supportive care, such as dialysis or a heart pump, death is imminent.

Once a person is designated as a transplant candidate, their name and medical profile are added to the UNOS computer list. The UNOS list includes all potential transplant recipients in the United States.

The person is not placed on a ranked list at that time. Rather, their name is added to the "pool" of those awaiting transplant. When a potential donor organ becomes available, each person in the "pool" is matched by the computer against the donor organ characteristics. The computer then generates a list of people ranked in order based upon medical and scientific criteria, comparing everyone in the "pool" to that particular donor organ.

Factors affecting ranking may include tissue match, blood type, length of time on the waiting list and immune status. In the case of heart, heart-lung, liver, lung and pancreas, the potential recipient's distance from the donor hospital is also considered. Therefore, each donor will generate a differently ranked list of patients.

Often the top ranked person on the waiting list will not receive the organ for one of several reasons. They must be available, be healthy enough to tolerate major surgery and be willing to undergo transplant immediately. Also, compatibility testing between the donor and recipient may indicate that the donor organ will be rejected by the potential recipient's immune system.