The equitable allocation of deceased donor lungs for transplant in children in the United States

Recipient selection for lung transplantation: perspective in decision-making

BACKGROUND

To determine the conditions that prevented transplant in patients referred to our center due to end-stage lung disease.

STUDY DESIGN

Descriptive study.

PLACE AND DURATION OF THE STUDY

Department of lung transplant clinic, Koşuyolu High Specialization Education and Research Hospital, Istanbul, Turkey, from December 2017 to January 2022.

METHODS

Patients with end-stage lung disease referred to our clinic were retrospectively evaluated with regard to reasons for exclusion, diagnosis, and demographic data. The Karnofsky Performance Status scoring scale was used to measure the functional status of the patients.

RESULTS

A total of 311 patients were evaluated during the study period. The mean age was 44.2 (range 4-73) years. There were 207 (66.6%) male patients. The most common indications were idiopathic interstitial pneumonia in 104 (33.4%) patients, chronic obstructive pulmonary disease in 53 (17%) patients, bronchiectasis in 49 (15.7%) patients, and cystic fibrosis in 28 (9%) patients. Of the patients, 106 (34%) were not appropriate candidates for a lung transplant. The most common reasons for refusal were preventable situations such as activity limitation and poor performance in 53 (50%) patients, weight in 49 (46.2%) patients, and smoking in 10 (9.4%) patients.

CONCLUSION

Impaired performance status was the most common cause of lung transplant exclusion. Weight and smoking were preventable causes of exclusion. Implementing pulmonary rehabilitation in very few patients was the most important handicap. It is believed that providing optimal treatment with a multidisciplinary approach and timely referral to transplant centers will significantly reduce the reasons for exclusion. Key message What is already known on this topic?  Referring lung transplant candidates to clinics at the earliest stage is essential for assessing their condition and exploring treatment options. What this study adds?  Factors like smoking, obesity, and muscle loss can hinder the transplantation process; thus, timely interventions are crucial. The primary reason for excluding candidates from lung transplantation is the decline in performance status. How this study might affect research, practice or policy?  Programs focused on smoking cessation, weight management, and muscle strengthening can play a vital role in enhancing patients' health before transplantation. It is imperative to expand and enhance the accessibility of pulmonary rehabilitation programs.

The Lung Allocation Score and Its Relevance

Lung transplantation in the United States, under oversight by the Organ Procurement Transplantation Network (OPTN) in the 1990s, operated under a system of allocation based on location within geographic donor service areas, wait time of potential recipients, and ABO compatibility. On May 4, 2005, the lung allocation score (LAS) was implemented by the OPTN Thoracic Organ Transplantation Committee to prioritize patients on the wait list based on a balance of wait list mortality and posttransplant survival, thus eliminating time on the wait list as a factor of prioritization. Patients were categorized into four main disease categories labeled group A (obstructive lung disease), B (pulmonary hypertension), C (cystic fibrosis), and D (restrictive lung disease/interstitial lung disease) with variables within each group impacting the calculation of the LAS. Implementation of the LAS led to a decrease in the number of wait list deaths without an increase in 1-year posttransplant survival. LAS adjustments through the addition, modification or elimination of covariates to improve the estimates of patient severity of illness, have since been made in addition to establishing criteria for LAS value exceptions for pulmonary hypertension patients. Despite the success of the LAS, concerns about the prioritization, and transplantation of older, sicker individuals have made some aspects of the LAS controversial. Future changes in US lung allocation are anticipated with the current development of a continuous distribution model that incorporates the LAS, geographic distribution, and unaccounted aspects of organ allocation into an integrated score.

The ethical debate over child priority in post-mortem organ allocation: A scoping review and practical-ethical outlook

BACKGROUND

Organ allocation guidelines in many countries give children relative priority, but the normative justification of child priority is seldom articulated.

METHODOLOGY

We conducted a scoping review of the recent international literature (2013-2019) to identify moral positions and normative frameworks to justify or criticize pediatric priority in all kind of organ allocation. We identified 11 relevant papers.

RESULTS

Our analysis revealed a complex juxtaposition of pro and contra argumentations along three main normative lines: a) equal treatment of each individual, b) individual benefit, and c) social benefit and the public good. The general type of argument can be found independent of the organ allocated. For each of these three lines we identified and categorized two types of argumentations: those in favor and those critical of the priority rule. Additionally, we discuss a problematic issue that has not yet been mentioned in the literature, namely the effects of age thresholds related to child-priority rules in organ allocation. We illustrate this problem with an analysis of selected German data with allocated postmortal kidneys and livers. These data show non-normal distributions of organ transplantations and waiting times for patients between the ages of 16 and 19.

DISCUSSION

Our overview serves as a matrix to reconsider existing guideline policy. The review can assist policy makers or experts on organ allocation committees in increasing the transparency of child priority rules, in explaining their justifications, and in reforming existing guidelines.

Lung transplantation: indications and contraindications

The selection of appropriate recipients for lung transplantation is an evolving discipline. As experience with the procedure has developed over the last decades, the identification of transplant candidates has also changed as transplant centers strive to safely provide the therapy to as many patients possible. The International Society for Heart and Lung Transplantation (ISHLT) has developed three editions of recipient selection guidelines. Published in 1998, 2006, and 2015, these guidelines represented the best information relevant to the appropriate selection of lung transplant candidates. A discussion of areas supported by the most robust scientific data will be undertaken, but in many aspects of recipient selection, there is a paucity of data upon which to rely. Therefore, it is ultimately the prerogative and responsibility of individual centers to determine, after carefully weighing the best evidence available, whether a patient is deemed a suitable candidate at a specific program. All possible indications and contraindications for transplantation will be reviewed with attention also given to the appropriate timing of referral and listing of patients with advanced lung disease to a transplant center.

Improved waitlist and transplant outcomes for pediatric lung transplantation after implementation of the lung allocation score

BACKGROUND

Although the lung allocation score (LAS) has not been considered valid for lung allocation to children, several additional policy changes for pediatric lung allocation have been adopted since its implementation. We compared changes in waitlist and transplant outcomes for pediatric and adult lung transplant candidates since LAS implementation.

METHODS

The United Network for Organ Sharing database was reviewed for all lung transplant listings during the period 1995 to June 2014. Outcomes were analyzed based on date of listing (pre-LAS vs post-LAS) and candidate age at listing (adults >18 years, adolescents 12 to 17 years, children 0 to 11 years).

RESULTS

Of the 39,962 total listings, 2,096 (5%) were for pediatric candidates. Median waiting time decreased after LAS implementation for all age groups (adults: 379 vs 83 days; adolescents: 414 vs 104 days; children: 211 vs 109 days; p < 0.001). The proportion of candidates reaching transplant increased after LAS (adults: 52.6% vs 71.6%, p < 0.001; adolescents: 40.3% vs 61.6%, p < 0.001; children: 42.4% vs 50.9%, p = 0.014), whereas deaths on the waitlist decreased (adults: 28.0% vs 14.4%, p < 0.001; adolescents: 33.1% vs 20.9%, p < 0.001; children: 32.2% vs 25.0%; p = 0.025), despite more critically ill candidates in all groups. Median recipient survival increased after LAS for adults and children (adults: 5.1 vs 5.5 years, p < 0.001; children: 6.5 vs 7.6 years, p = 0.047), but not for adolescents (3.6 vs 4.3 years, p = 0.295).

CONCLUSIONS

Improvements in waiting time, mortality and post-transplant survival have occurred in children after LAS implementation. Continued refinement of urgency-based allocation to children and broader sharing of pediatric donor lungs may help to maximize these benefits.

Broader Geographic Sharing of Pediatric Donor Lungs Improves Pediatric Access to Transplant

US pediatric transplant candidates have limited access to lung transplant due to the small number of donors within current geographic boundaries, leading to assertions that the current lung allocation system does not adequately serve pediatric patients. We hypothesized that broader geographic sharing of pediatric (adolescent, 12-17 years; child, <12 years) donor lungs would increase pediatric candidate access to transplant. We used the thoracic simulated allocation model to simulate broader geographic sharing. Simulation 1 used current allocation rules. Simulation 2 offered adolescent donor lungs across a wider geographic area to adolescents. Simulation 3 offered child donor lungs across a wider geographic area to adolescents. Simulation 4 combined simulations 2 and 3. Simulation 5 prioritized adolescent donor lungs to children across a wider geographic area. Simulation 4 resulted in 461 adolescent transplants per 100 patient-years on the waiting list (range 417-542), compared with 206 (range 180-228) under current rules. Simulation 5 resulted in 388 adolescent transplants per 100 patient-years on the waiting list (range 348-418) and likely increased transplant rates for children. Adult transplant rates, waitlist mortality, and 1-year posttransplant mortality were not adversely affected. Broader geographic sharing of pediatric donor lungs may increase pediatric candidate access to lung transplant.

Lung Transplantation

The therapeutic options for patients with advanced pulmonary parenchymal or vascular disorders are currently limited. Lung transplantation remains one of the few viable interventions, but on account of the insufficient donor pool only a minority of these patients actually undergo the procedure each year. Following transplantation there are a number of early and late allograft complications such as primary graft dysfunction, allograft rejection, infection, post-transplant lymphoproliferative disorder and late injury that is now classified as chronic lung allograft dysfunction. The pathologist plays an essential role in the diagnosis and classification of these myriad complications. Although the transplant procedures are performed in selected centers patients typically return to their local centers. When complications arise it is often the responsibility of the local pathologist to evaluate specimens. Therefore familiarity with the pathology of lung transplantation is important.

Current State of Pediatric Lung Transplantation

Cardiothoracic transplantation has significantly impacted the lives of pediatric patients with advanced cardiopulmonary failure. The current state of lung transplantation in children as well as its ongoing and future challenges are discussed.

Was Sarah Murnaghan treated justly?

Lung transplantation is a potentially life-saving procedure for patients with irreversible lung failure. Five-year survival rates after lung transplantation are >50% for children and young adults. But there are not enough lungs to save everyone who could benefit. In 2005, the United Network for Organ Sharing developed a scoring system to prioritize patients for transplantation. That system considered transplant urgency as well as time on the waiting list and the likelihood that the patient would benefit from the transplant. At the time, there were so few pediatric lung transplants that the data that were used to develop the Lung Allocation Score were inadequate to analyze and prioritize children, so they were left out of the Lung Allocation Score system. In 2013, the family of a 10-year-old challenged this system, claiming that it was unjust to children. In the article, we asked experts in health policy, bioethics, and transplantation to discuss the issues in the Murnaghan case.

A consensus document for the selection of lung transplant candidates: 2014--an update from the Pulmonary Transplantation Council of the International Society for Heart and Lung Transplantation

The appropriate selection of lung transplant recipients is an important determinant of outcomes. This consensus document is an update of the recipient selection guidelines published in 2006. The Pulmonary Council of the International Society for Heart and Lung Transplantation (ISHLT) organized a Writing Committee of international experts to provide consensus opinion regarding the appropriate timing of referral and listing of candidates for lung transplantation. A comprehensive search of the medical literature was conducted with the assistance of a medical librarian. Writing Committee members were assigned specific topics to research and discuss. The Chairs of the Writing Committee were responsible for evaluating the completeness of the literature search, providing editorial support for the manuscript, and organizing group discussions regarding its content. The consensus document makes specific recommendations regarding the timing of referral and of listing for lung transplantation. These recommendations include discussions not present in previous ISHLT guidelines, including lung allocation scores, bridging to transplant with mechanical circulatory and ventilator support, and expanded indications for lung transplantation. In the absence of high-grade evidence to support decision making, these consensus guidelines remain part of a continuum of expert opinion based on available studies and personal experience. Some positions are immutable. Although transplant is rightly a treatment of last resort for end-stage lung disease, early referral allows proper evaluation and thorough patient education. Subsequent waiting list activation implies a tacit agreement that transplant offers a significant individual survival advantage. It is both the challenge and the responsibility of the transplant community globally to ensure organ allocation maximizes the potential benefits of a scarce resource, thereby achieving that advantage.