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Lungs are allocated to adult and adolescent transplant candidates (aged ě 12 years) on the basis of age, geography, blood type compatibility, and the lung allocation score (LAS), which reflects risk of waitlist mortality and probability of posttransplant survival. In 2013, the most adult candidates, 2394, of any year were added to the list. Overall median waiting time for candidates listed in 2013 was 4.0 months. The preferred procedure remained bilateral lung transplant, representing approximately 70% of lung transplants in 2013. Measures of short-term and longterm survival have plateaued since the implementation of the LAS in 2005. The number of new child candidates (aged 0-11 years) added to the lung transplant waiting list increased to 39 in 2013. A total of 28 lung transplants were performed in child recipients, 3 for ages younger than 1 year, 9 for ages 1 to 5 years, and 16 for ages 6 to 11 years. The diagnosis of pulmonary hypertension was associated with higher survival rates than cystic fibrosis or other diagnosis (pulmonary fibrosis, bronchiolitis obliterans, bronchopulmonary dysplasia). For child candidates, infection was the leading cause of death in year 1 posttransplant and graft failure in years 2 to 5.

This document was developed through the collaborative efforts of the Society of Critical Care Medicine, the American College of Chest Physicians, and the Association of Organ Procurement Organizations. Under the auspices of these societies, a multidisciplinary, multi-institutional task force was convened, incorporating expertise in critical care medicine, organ donor management, and transplantation. Members of the task force were divided into 13 subcommittees, each focused on one of the following general or organ-specific areas: death determination using neurologic criteria, donation after circulatory death determination, authorization process, general contraindications to donation, hemodynamic management, endocrine dysfunction and hormone replacement therapy, pediatric donor management, cardiac donation, lung donation, liver donation, kidney donation, small bowel donation, and pancreas donation. Subcommittees were charged with generating a series of management-related questions related to their topic. For each question, subcommittees provided a summary of relevant literature and specific recommendations. The specific recommendations were approved by all members of the task force and then assembled into a complete document. Because the available literature was overwhelmingly comprised of observational studies and case series, representing low-quality evidence, a decision was made that the document would assume the form of a consensus statement rather than a formally graded guideline. The goal of this document is to provide critical care practitioners with essential information and practical recommendations related to management of the potential organ donor, based on the available literature and expert consensus.

Lung transplants are increasingly used as treatment for end-stage lung diseases not amenable to other medical and surgical therapies. Lungs are allocated to adult and adolescent transplant candidates on the basis of age, geography, blood type compatibility, and the Lung Allocation Score, which reflects risk of wait-list mortality and probability of posttransplant survival. The overall median waiting time in 2012 was 4 months, and 65.3% of candidates underwent transplant within 1 year of listing; however, this proportion varied greatly by donation service area. Unadjusted median survival of lung transplant recipients was 5.3 years in 2012, and median survival conditional on living for 1 year posttransplant was 6.7 years. Among pediatric lung candidates in 2012, 32.1% were wait-listed for less than 1 year, 17.9% for 1 to less than 2 years, 16.7% for 2 to less than 4 years, and 33.3% for 4 or more years. Both graft and patient survival have continued to improve; survival rates for recipients aged 6-11 years are better than for younger recipients. Compared with recipients of other solid organ transplants, lung transplant recipients experienced the highest rates of rehospitalization for transplant complications: 43.7 per 100 patients in year 1 and 36.0 in year 2.

In 2016, 2692 candidates aged 12 years or older were added to the lung transplant waiting list; 2345 transplants were performed, the largest number of any prior year. The median waiting time for listed candidates in 2016 was 2.5 months, and waiting times were shortest for group D candidates. The transplant rate increased to 191.9 transplants per 100 waitlist years in 2016, with a slight decrease in waitlist mortality to 15.1 deaths per 100 waitlist years. Short-term survival continued to improve, with a 6-month death rate of 6.6% and a 1-year death rate of 10.8% among recipients in 2015 compared with 8.0% and 13.3%, respectively, among recipients in 2014. Long-term survival rates remained unchanged; 55.6% of recipients were alive at 5 years. In 2016, 23 new candidates aged 0-11 years were added to the waiting list and 16 lung transplants were performed. Incidence of posttransplant mortality for lung transplant recipients aged 0-11 years who underwent transplant in 2014-2015 was 13.8% 1 at 6 months and 19.6% at 1 year. Changes in waitlist and transplant demographic features continued to evolve following implementation of the revised lung allocation score in 2015. Some early trends that may be attributable to the revised LAS are shorter waiting times, stabilization of the number of group D candidates listed for transplant, and convergence of LAS with lower prevalence of extremely high scores.

The number of lung transplants performed continues to increase annually and reached an all‐time high in 2019, with decreasing waitlist mortality. These trends are attributable to an increasing number of candidates listed for transplant each year and a continuing increase in the number of donors. Despite these favorable trends, 6.4% of lungs recovered for transplant were not transplanted in 2019, and strategies to optimize use of these available organs may reduce the number of waitlist even further. Time to transplant continued to decrease, as over 50% of candidates waited 3 months or less in 2019, yet regional heterogeneity remained despite policy changes intended to improve allocation equity. Small gains continued in posttransplant survival, with 1‐year survival at 88.8%; 3 year, 74.4%; 5 year, 59.2%, and 10 year, 33.1 %.

Lungs are allocated in part based on the Lung Allocation Score (LAS), which considers risk of death without transplant and posttransplant. Wait-list additions have been increasing steadily after an initial decline following LAS implementation. In 2011, the largest number of adult candidates were added to the waiting list in a single year since 1998; donation and transplant rates have been unable to keep pace with wait-list additions. Candidates aged 65 years or older have been added faster than candidates in other age groups. After an initial decline following LAS implementation, wait-list mortality increased to 15.7 per 100 wait-list years in 2011. Short-and long-term graft survival improved in 2011; 10-year graft failure fell to an all-time low. Since 1998, the number of new pediatric (aged 0-11 years) candidates added yearly to the waiting list has declined. In 2011, 19 pediatric lung transplants were performed, a transplant rate of 34.7 per 100 wait-list years. The percentage of patients hospitalized before transplant has not changed. Both graft and patient survival have continued to improve over the past decade. Posttransplant complications for pediatric lung transplant recipients, similar to complications for adult recipients, include hypertension, renal dysfunction, diabetes, bronchiolitis obliterans syndrome, and malignancy.

Lung and heart allocation in the United States has evolved over the past 20-30 years to better serve transplant candidates and improve organ utilization. The current lung allocation policy, based on the Lung Allocation Score, attempts to take into account risk of death on the waiting list and chance of survival posttransplant. This policy is flexible and can be adjusted to improve the predictive ability of the score. Similarly, in response to the changing clinical phenotype of heart transplant candidates, heart allocation policies have evolved to a multitiered algorithm that attempts to prioritize organs to the most infirm, a designation that fluctuates with trends in therapy. The Organ Procurement and Transplantation Network and its committees have been responsive, as demonstrated by recent modifications to pediatric heart allocation and mechanical circulatory support policies and by ongoing efforts to ensure that heart allocation policies are equitable and current. Here we examine the development of US lung and heart allocation policy, evaluate the application of the current policy on clinical practice and explore future directions for lung and heart allocation.