Pro/Con debate: lung allocation should be based on medical urgency and transplant survival and not on waiting time.

L ung transplantation is an acceptable therapy with which to palliate patients with a variety of endstage lung diseases, but there is a severe shortage of suitable donor lungs to meet the demand (Fig 1), which hinders broad application. In the last 5 years, approximately 2,500 potential lung recipients have died while on the UNOS lung transplant waiting list.1 Because of the shortage of lungs for transplantation, strict listing criteria have been espoused2; thus, the deaths of patients on the waiting list underrepresent the extent of the donor shortage. The discrepancy between the supply of organs and the demand for them as lifesaving therapies has resulted in the intense scrutiny of organ distribution systems and algorithms. In 1999, the US Department of Health and Human Services (DHHS) published “the Final Rule” a directive to UNOS, the Organ Procurement and Tissue Network (OPTN) contractor, to examine organ distribution policies and make changes that would direct organs to patients who were most in need, minimizing effects of geography.3 A report was commissioned by the Institute of Medicine4 to respond to the publication of the final rule. Although the Institute of Medicine report4 focused on liver transplantation, it was the directive of the DHHS that the OPTN review all organ distribution algorithms and report to the DHHS on alterations to distribution algorithms or provide justification that the system met the objectives espoused in the rule. This resulted in the creation of the Lung Allocation Subcommittee of the UNOS Thoracic Organ Committee to make recommendations to UNOS and the transplant community at large concerning policies for the distribution of donated lungs. After several years of analyses, discussion, public comment, and forums, in June 2004 the UNOS Board of Directors accepted the recommendation of the subcommittee to replace the existing lung distribution system with an entirely new algorithm.) The current system, based primarily on the allocation of lungs by waiting time, gave way in the spring of 2005 to a system that allocates lungs by calculating a lung allocation score (LAS) [defined below] for each candidate.