American Journal of Transplantation 2014; 14: 1234–1235 Wiley Periodicals Inc.
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Copyright 2014 The American Society of Transplantation and the American Society of Transplant Surgeons doi: 10.1111/ajt.12754
Editorial
The Lung Allocation Score Goes Global T. M. Egan* Division of Cardiothoracic Surgery, Department of Surgery, University of North Carolina at Chapel Hill, Chapel Hill, NC Corresponding author: Thomas M. Egan, [email protected]
Received 19 February 2014, revised 17 March 2014 and accepted for publication 25 March 2014 Lung disease is the third leading cause of death in the United States. Lung transplant is an effective palliative procedure, but is severely limited by the number of suitable lungs for transplant from conventional brain-dead organ donors and the inadequate number of organ donors. This has prompted considerable discussion regarding organ allocation policies. After 6 years of analysis, a new US system of lung allocation was adopted in May 2005 by the Organ Procurement and Transplantation Network (OPTN) based on a lung allocation score (LAS), calculated from predicted waitlist mortality without a transplant as a measure of urgency and estimated transplant benefit (1). Other nations have since used the US allocation policy as a model. In this issue, Gottlieb et al report the early results of implementation of the LAS system in Germany (2). This coincided with Eurotransplant’s decision to distribute lungs, when not used locally, to patients with a LAS > 50. Use of the LAS in Germany was associated with more lung transplants, despite no increase in organ donors, a significant reduction in lung waitlist deaths and no change in short-term posttransplant survival. After LAS introduction in 2005, OPTN data show an increase in the number of lung transplants performed, a decrease in waitlist deaths and a shift from chronic obstructive pulmonary disease to fibrotic lung disease as the major indication for transplant in the United States. Before adoption of a score, the German and US lung allocation systems differed considerably (Table 1). Before LAS, lungs in the United States were allocated based on waiting time and geography; while in Germany, allocation was already based on a measure of urgency. Allocation by urgency in Germany likely mitigated the impact of the new allocation system that prioritizes based on a different measure of urgency and benefit. 1234
What are the takeaway messages? In both Germany and the United States, LAS was associated with more lung transplant procedures. However, figure 2 in the Gottlieb article shows the number of lungs transplanted in Germany had been increasing since 2008, so it is not clear that the increase was due to LAS. Approximately, one-third of lungs were rescue allocation, when the organ has been declined three times and then is offered to a transplant center that can pick a candidate without regard to LAS, urgency or waiting time; the impact of LAS in Germany was ‘‘diluted’’ by this practice, the article said. Plans to require rescue allocation to be based on LAS may reduce this effect. In Germany, the median score of lungs transplanted using LAS was 48, higher than in the United States. When the US LAS system was implemented, the median LAS at transplant was 36.6; it increased to 40.8 in 2011, the last year for which data is available (3). Why the difference? Almost certainly, it’s the impact of geography on allocation. In Germany, lungs are allocated across the nation; in the United States, lungs are allocated by LAS first within a donor service area overseen by one of 58 organ procurement organizations (OPOs). A consequence is that many US patients receive lungs with lower LAS than would occur if lungs were offered over a broader geographic area. In one calendar year, 83% of double lung transplant procedures were performed in recipients with lower LAS than size-matched ABO-compatible recipients in the same region (4). Although a national allocation system may not be practical in the United States, and Germany is much smaller than the United States, the German experience suggests that broader geographic sharing should result in transplanting patients with a higher LAS. This should reduce waitlist deaths further. Pediatric allocation is different (Table 1). In both countries, this affects a very small proportion of transplants. In Germany, pediatric lungs are allocated nationally with preference to pediatric recipients. In the United States, pediatric donors are allocated preferentially to pediatric recipients, but only within a local OPO. Broader geographic sharing of pediatric donor lungs would probably meet the need of pediatric recipients, and would likely have resolved the 2013 Murnaghan case (5), in which parents sued for an exception to allocation policy to speed a transplant for their daughter. The OPTN has largely ignored the Final Rule requirement to minimize the impact of geography and waiting time.
LAS in Germany and United States Table 1: Characteristics of lung allocation systems pre- and post-LAS introduction in United States and Germany Pre-LAS United States
Geography Ability to import
Germany
United States
Germany
By LAS > age 11 rescue allocation for 1/3 Waiting time no
C
Copyright 2014 The American Society of Transplantation and the American Society of Transplant Surgeons doi: 10.1111/ajt.12754
Editorial
The Lung Allocation Score Goes Global T. M. Egan* Division of Cardiothoracic Surgery, Department of Surgery, University of North Carolina at Chapel Hill, Chapel Hill, NC Corresponding author: Thomas M. Egan, [email protected]
Received 19 February 2014, revised 17 March 2014 and accepted for publication 25 March 2014 Lung disease is the third leading cause of death in the United States. Lung transplant is an effective palliative procedure, but is severely limited by the number of suitable lungs for transplant from conventional brain-dead organ donors and the inadequate number of organ donors. This has prompted considerable discussion regarding organ allocation policies. After 6 years of analysis, a new US system of lung allocation was adopted in May 2005 by the Organ Procurement and Transplantation Network (OPTN) based on a lung allocation score (LAS), calculated from predicted waitlist mortality without a transplant as a measure of urgency and estimated transplant benefit (1). Other nations have since used the US allocation policy as a model. In this issue, Gottlieb et al report the early results of implementation of the LAS system in Germany (2). This coincided with Eurotransplant’s decision to distribute lungs, when not used locally, to patients with a LAS > 50. Use of the LAS in Germany was associated with more lung transplants, despite no increase in organ donors, a significant reduction in lung waitlist deaths and no change in short-term posttransplant survival. After LAS introduction in 2005, OPTN data show an increase in the number of lung transplants performed, a decrease in waitlist deaths and a shift from chronic obstructive pulmonary disease to fibrotic lung disease as the major indication for transplant in the United States. Before adoption of a score, the German and US lung allocation systems differed considerably (Table 1). Before LAS, lungs in the United States were allocated based on waiting time and geography; while in Germany, allocation was already based on a measure of urgency. Allocation by urgency in Germany likely mitigated the impact of the new allocation system that prioritizes based on a different measure of urgency and benefit. 1234
What are the takeaway messages? In both Germany and the United States, LAS was associated with more lung transplant procedures. However, figure 2 in the Gottlieb article shows the number of lungs transplanted in Germany had been increasing since 2008, so it is not clear that the increase was due to LAS. Approximately, one-third of lungs were rescue allocation, when the organ has been declined three times and then is offered to a transplant center that can pick a candidate without regard to LAS, urgency or waiting time; the impact of LAS in Germany was ‘‘diluted’’ by this practice, the article said. Plans to require rescue allocation to be based on LAS may reduce this effect. In Germany, the median score of lungs transplanted using LAS was 48, higher than in the United States. When the US LAS system was implemented, the median LAS at transplant was 36.6; it increased to 40.8 in 2011, the last year for which data is available (3). Why the difference? Almost certainly, it’s the impact of geography on allocation. In Germany, lungs are allocated across the nation; in the United States, lungs are allocated by LAS first within a donor service area overseen by one of 58 organ procurement organizations (OPOs). A consequence is that many US patients receive lungs with lower LAS than would occur if lungs were offered over a broader geographic area. In one calendar year, 83% of double lung transplant procedures were performed in recipients with lower LAS than size-matched ABO-compatible recipients in the same region (4). Although a national allocation system may not be practical in the United States, and Germany is much smaller than the United States, the German experience suggests that broader geographic sharing should result in transplanting patients with a higher LAS. This should reduce waitlist deaths further. Pediatric allocation is different (Table 1). In both countries, this affects a very small proportion of transplants. In Germany, pediatric lungs are allocated nationally with preference to pediatric recipients. In the United States, pediatric donors are allocated preferentially to pediatric recipients, but only within a local OPO. Broader geographic sharing of pediatric donor lungs would probably meet the need of pediatric recipients, and would likely have resolved the 2013 Murnaghan case (5), in which parents sued for an exception to allocation policy to speed a transplant for their daughter. The OPTN has largely ignored the Final Rule requirement to minimize the impact of geography and waiting time.
LAS in Germany and United States Table 1: Characteristics of lung allocation systems pre- and post-LAS introduction in United States and Germany Pre-LAS United States
Geography Ability to import
Germany
United States
Germany
By LAS > age 11 rescue allocation for 1/3 Waiting time no
