A data monitoring report contains key measures of the current lung allocation system, which was implemented March 9, 2023, by the Organ Procurement and Transplantation Network (OPTN).
The new patient-centric and flexible system utilizes a framework known as continuous distribution that combines all factors used in the organ match into a single score for each lung transplant candidate. This policy was projected to decrease deaths among waitlisted patients and increase lung transplants for the most medically urgent candidates. Since implementation, approximately 1/3 of transplants performed have been for candidates in the highest medical urgency category (with >= 2.5 medical urgency points).
The report notes several key trends since implementation, including:
- A 15.9 percent increase in lung transplants1
- A decrease in the number of candidates removed from the waiting list due to death or being too sick for transplant (52 pre-policy era to 30 post-policy era)
- No negative impact on lung utilization2 (16.5 percent utilization in the pre-era and 17.8 percent utilization in the post-policy era)
Other key points to note:
- Decrease in number of transplants for blood type O recipients from 308 pre-policy era to 276 post-policy era
- Increase in median distance (this is the distance from the donor hospital to the transplant hospital) from 193 nautical miles to 344 nautical miles
- Increase in the number of registrations with at least one submitted exception request3 (from 38 pre-policy era to 120 post-policy era)
The report was presented to the OPTN Lung Transplantation Committee July 13, 2023. Note: It was determined in July 2023 that the modeling results used to inform development of the continuous distribution policy did not incorporate screening for incompatible blood types in the simulation. The OPTN Board of Directors approved a policy update on Sept. 22, 2023, to improve access to transplant for blood type O candidates, and the policy change was implemented on Sept. 27, 2023. For more information, refer to the policy notice.
The Lung Committee will continue to monitor this policy to understand whether the changes are meeting intended goals, and to determine if the changes have resulted in any unintended consequences. If so, the Lung Committee can propose further changes to the policy. Subsequent monitoring reports will be published on the OPTN website after six months and then annually for the next three years as outlined in the briefing paper.
Background
In 2019, the OPTN began work to adopt a single distribution framework that could be adapted to all organ types. This approach, known as continuous distribution, is a points-based system predicted to increase equity among potential recipients. Lung was the first organ type to adopt continuous distribution. Kidney, pancreas and liver are currently moving through a series of steps as the framework is developed for their organ types. Heart has also begun policy development with a concept paper going out for public comment this summer. Read more about the continuous distribution framework.
1This number does not include multi-organ transplants performed during the reporting period (for example, heart-lung).
2The utilization rate is defined as the percent of lungs that are transplanted based on all possible lungs from every deceased donor with at least one organ recovered for the purpose of transplant; this assumes that each donor has two possible lungs for donation.
3Under the previous lung allocation system, a candidate could only have one exception, but under the new system, a candidate is allowed to have exceptions for multiple factors at once.
