A new way of allocating donor lungs that eliminates geographical restrictions could save more lives, new research suggests.

In early 2023, the current U.S. system, which looks for compatible candidates within a fixed radius, will be replaced by the Composite Allocation Score. The new score will prioritize a candidate’s medical needs.

“The importance of removing the geographical barrier can’t be overstated here,” said study author Dr. Maryam Valapour, senior investigator for lung transplantation at the U.S. Scientific Registry of Transplant Recipients (SRTR). “The Composite Allocation Score system’s goal of making access to lung transplant more equitable for all candidates in the United States will help reduce waitlist [death rates] and we hope will even improve post-transplant survival over time.”

The current system gauges donor and recipient compatibility, geographical restrictions and prioritizes calculated survival after transplant, according to a study led by Valapour and colleagues at the SRTR and the Cleveland Clinic, where she is director of lung transplant outcomes.

That system first looks at compatibility within a 250-mile radius. But someone who needs the lungs more quickly may live just outside that boundary.

The new system is meant to improve equity in organ allocation by prioritizing a patient’s medical needs and eliminating geographical boundaries.

To investigate the potential impact of the change, Valapour’s team tested six alternate scenarios in 10 simulations. They used data from individuals who had been on the waiting list from Jan. 1, 2018, through Dec. 31, 2019.

Depending on the scenario, waitlist deaths decreased anywhere from 36% to 47%, in the Composite Allocation Score system.

Across all scenarios, this led to improved measures of equity, the researchers reported. Post-transplant survival also rose.

“With more candidates added to the waitlist every day, access to available lungs is incredibly important,” said study co-author Dr. Carli Lehr, a pulmonary and critical care physician at the Cleveland Clinic, in Ohio.

“The Composite Allocation Score system will help those on the waitlist overcome challenges associated with their proximity to potential donors,” Lehr explained in a clinic news release.

The new system could set a precedent for all organs for the Organ Procurement and Transplantation Network and the United Network for Organ Sharing (UNOS), the researchers said. UNOS is the private, non-profit that manages the U.S. organ transplantation system.

Last year, more than 3,000 people were added to the lung transplant waitlist. More than 2,600 lung transplants were performed. A shortage of available organs still exists in the United States.

The study findings were recently published online in the American Journal of Transplantation.

More information

The United Network for Organ Sharing has more on how to become an organ donor.

SOURCE: Cleveland Clinic, news release, Jan. 5, 2023