What is the Lung Allocation Score?

The lung allocation score (LAS) is an important factor in determining priority for receiving a lung transplant when a donor lung becomes available. The system determines the order of everyone awaiting a lung transplant by their lung allocation scores, blood type and geographic distance between the candidates and the hospital where the lung donor is located. Age also plays a role because lungs from pediatric and adolescent donors are offered first to pediatric and adolescent transplant candidates before they are offered to adults.

The lung allocation system uses medical information specific to each lung transplant candidate. This information includes lab values, test results and disease diagnosis and is used to calculate an LAS from 0 to 100. The score represents an estimate of the severity of every candidate’s illness and the chance of success following a lung transplant. All candidates are placed in order for compatible lung offers according to their score: A candidate with a higher lung allocation score receives higher priority for a lung offer when a compatible lung becomes available.

The supply of donor lungs is limited. The OPTN designed this allocation system to more effectively use the limited number of available donor lungs as well as reduce the number of deaths among people waiting for a transplant. Prior to this system, transplant candidates received donor lungs based on the amount of time they had been on the waitlist. The lung allocation score system is based on scientific data regarding lung transplantation and by drawing on prior experience with many types of people with lung diseases, and offers donor lungs to candidates according to their medical characteristics.