Prediction of Donor Heart Acceptance for Transplant and Its Clinical Implications: Results From The Donor Heart Study.

BACKGROUND: Despite a shortage of potential donors for heart transplant in the United States, most potential donor hearts are discarded. We evaluated predictors of donor heart acceptance in the United States and applied machine learning methods to improve prediction. METHODS: We included a nationwide (2005-2020) cohort of potential heart donors in the United States (n=73 948) from the Scientific Registry of Transplant Recipients and a more recent (2015-2020) rigorously phenotyped cohort of potential donors from DHS (Donor Heart Study; n=4130). We identified predictors of acceptance for heart transplant in both cohorts using multivariate logistic regression, incorporating time-interaction terms to characterize their varying effects over time. We fit models predicting acceptance for transplant in a 50% training subset of DHS using logistic regression, least absolute shrinkage and selection operator, and random forest algorithms and compared their performance in the remaining 50% (test) of the subset. RESULTS: Predictors of donor heart acceptance were similar in the nationwide and DHS cohorts. Among these, older age (P value for time interaction, 0.0001) has become increasingly predictive of discard over time while other factors, including those related to drug use, infection, and mild cardiac diagnostic abnormalities, have become less influential (P value for time interaction, <0.05 for all). A random forest model (area under the curve, 0.908; accuracy, 0.831) outperformed other prediction algorithms in the test subset and was used as the basis of a novel web-based prediction tool. CONCLUSIONS: Predictors of donor heart acceptance for transplantation have changed significantly over the last 2 decades, likely reflecting evolving evidence regarding their impact on posttransplant outcomes. Real-time prediction of donor heart acceptance, using our web-based tool, may improve efficiency during donor management and heart allocation.

The Cost of Procuring Deceased Donor Livers: Evidence From US Organ Procurement Organization Cost Reports, 2013-2018.

Deceased donor organs for transplantation are costly. Expenses include donor assessment, pre-operative care of acceptable donors, surgical organ recovery, preservation and transport, and other costs. US Organ Procurement Organizations (OPOs) serve defined geographic areas in which each OPO has exclusive organ recovery responsibilities including detailed reporting of costs. We sought to determine the costs of procuring deceased donor livers by examining reported organ acquisition costs from OPO cost reports. Using 6 years of US OPO cost report data for each OPO (2013-2018), we determined the average cost of recovering a viable (i.e., transplanted) liver for each of the 51 independent US OPOs. We examined predictors of these costs including the number of livers procured, the percent of nonviable livers, direct procurement costs, coordinator salaries, professional education, and local cost of living. A cost curve estimated the relationship between the cost of livers and the number of locally procured livers. The average cost of procured livers by individual OPO-year varied widely from $11 393 to $65 556 (average $31 659) over the six study years. An increase in the overall number of procured livers was associated with lower direct costs, administrative, and procurement overhead costs, but this association differed for imported livers. Cost per local liver decreased linearly for each additional liver, while importing more livers was only cost saving until 200 livers, with imported livers costing more ($39K vs. $31.7K). The largest predictor of variation in cost was the aggregate of direct costs (e.g., hospital costs) to recover the organ (57%). Cost increases were 2.5% per year (+$766/year). This information may be valuable in determining how OPOs might improve service to transplant centers and the patients they serve.

Impact of the life-sustaining treatment decision act on organ donation in out-of-hospital cardiac arrests in South Korea: a multi-centre retrospective study.

BACKGROUND: The demand for organ transplants, both globally and in South Korea, substantially exceeds the supply, a situation that might have been aggravated by the enactment of the Life-Sustaining Treatment Decision Act (LSTDA) in February 2018. This legislation may influence emergency medical procedures and the availability of organs from brain-dead donors. This study aimed to assess LSTDA's impact, introduced in February 2018, on organ donation status in out-of-hospital cardiac arrest (OHCA) patients in a metropolitan city and identified related factors. METHODS: We conducted a retrospective analysis of a regional cardiac arrest registry. This study included patients aged 16 or older with cardiac arrest and a cerebral performance category (CPC) score of 5 from January 2015 to December 2022. The exclusion criteria were CPC scores of 1-4, patients under 16 years, and patients declared dead or transferred from emergency departments. Logistic regression analysis was used to analyse factors affecting organ donation. RESULTS: Of the 751 patients included in this study, 47 were organ donors, with a median age of 47 years. Before the LSTDA, there were 30 organ donations, which declined to 17 after its implementation. In the organ donation group, the causes of cardiac arrest included medical (34%), hanging (46.8%), and trauma (19.2%). The adjusted odds ratio for organ donation before the LSTDA implementation was 6.12 (95% CI 3.09-12.12), with non-medical aetiology as associated factors. CONCLUSION: The enactment of the LSTDA in 2018 in South Korea may be linked to reduced organ donations among patients with OHCA, underscoring the need to re-evaluate the medical and legal aspects of organ donation, especially considering end-of-life care decisions.

Small Donors, Big Impact: Optimizing Organ Utilization in Simultaneous Pancreas and Kidney Transplantation From Extra Small Pediatric Donors.

INTRODUCTION: Simultaneous pancreas-kidney transplantation (SPK) is the preferred treatment for individuals with type-1 diabetes and end-stage renal disease. However, a limited supply of "Ideal Pancreas Donors" contributed to a growing disparity between available organs and recipients. Even though SPK outcomes from pediatric donors match those from adult donors, unclear guidelines on minimum age and weight criteria for extra small pediatric pancreas donors lead to hesitancy among several transplant centers to utilize these grafts due to concerns about inadequate islet mass, technical challenges, and increased risk of allograft thrombosis. METHODS: This report details the successful outcomes of SPK transplantations performed at the study center between December 2021 and January 2024, using four extra small pediatric brain-dead donors (ESPDs). Each donor was aged ≤5 years and weighed <20 kg. RESULTS: All SPK recipients achieved immediate posttransplant euglycemia without requiring insulin. None of the recipients experienced graft pancreatitis, graft thrombosis, allograft rejection, or required re-exploration. During a 5-27-month follow-up period, all ESPD recipients maintained optimal graft function, as evidenced by normal glucose tolerance tests and HbA1c (4.9%-5.2%), with 100% graft and patient survival. CONCLUSION: This report examines the usage of ESPDs in SPK transplantation, highlighting their potential to expand the donor pool and reduce wait times in areas with scarce deceased organ donations, thereby increasing the number of available organs for transplantation with acceptable outcomes. Revising donor selection guidelines to reflect the diverse risk-benefit profiles of waitlisted individuals is crucial to addressing geographical disparities and reducing organ discard rates.

Risk and Reward: Nationwide Analysis of Cardiac Transplant Center Variation in Organ Travel Distance and the Effects on Outcomes.

BACKGROUND: The 2018 UNOS allocation policy change deprioritized geographic boundaries to organ distribution, and the effects of this change have been widespread. The aim of this investigation was to analyze changes in donor transplant center distance for organ travel and corresponding outcomes before and after the allocation policy change. METHODS: The UNOS database was utilized to identify all adult patients waitlisted for heart transplants from 2016 to 2021. Transplant centers were grouped by average donor heart travel distance based on whether they received more or less than 50% of organs from >250 miles away. Descriptive statistics were provided for waitlisted and transplanted patients. Regression analyses modeled waitlist mortality, incidence of transplant, overall survival, and graft survival. RESULTS: Centers with a longer average travel distance had a higher mean annual transplant volume with a reduction in total days on a waitlist (86.6 vs. 149.2 days), an increased cold ischemic time (3.6 vs. 3.2 h), with no significant difference in post-transplant overall survival or graft survival. CONCLUSIONS: The benefits of reducing waitlist time while preserving post-transplant outcomes extend broadly. The trends observed in this investigation will be useful as we revise organ transplant policy in the era of new organ procurement and preservation techniques.

Donation After Circulatory Death following Withdrawal of Life-Sustaining Treatments. Are We Ready to Break the Dead Donor Rule?

A fundamental criterion considered essential to deem the procedure of vital organ procurement for transplantation ethical is that the donor must be dead, as per the Dead Donor Rule (DDR). In the case of Donation after Circulatory Death (DCD), is the donor genuinely dead? The main aim of this article is to clarify this uncertainty, which primarily arises from the fact that in DCD, death is determined based on cardiac criteria (Circulatory Death, CD), rather than neurological criteria (Brain Death, BD), and that to allow the procurement procedure, physicians reperfuse the organs in an assisted manner. To ensure that the cessation of circulation leads to the irreversible loss of brain functions, DCD regulations require that physicians wait a certain period after CD before commencing vital organ procurement. However, during this "no-touch period," the organs are at risk of damage, potentially rendering them unsuitable for transplantation. When DCD is performed on patients whose CD follows a Withdrawal of Life-Sustaining Treatment (WLST) (DCD Maastricht III category), how long should the no-touch period last? Does its existence really make sense? Does beginning the procedure of vital organ procurement immediately after WLST constitute a violation of the DDR that can be ethically justified? The discussion aims to provide arguments in support of the non-absoluteness of the DDR.

Procurement Trends, Indications, and Outcomes of Heart-Lung Transplantation in the Contemporary Era.

BACKGROUND: Evolving trends in organ procurement and technological innovation prompted an investigation into recent trends, indications, and outcomes following combined heart-lung transplantation (HLTx). METHODS: The United Network for Organ Sharing database was queried for all adult (≥18 years) HLTx performed between July 1, 2013 and June 30, 2023. Patients with previous transplants were excluded. The primary endpoint was the effect of donor, recipient, and transplantation characteristics on 1- and 5-year survival. Secondary analyses included a comparison of HLTx at high- and low-volume centers, an assessment of HLTx following donation after circulatory death (DCD), and an evaluation of HLTx volume over time. Cox proportional-hazards models were used to assess factors associated with mortality. Temporal trends were evaluated with linear regression. RESULTS: After exclusions, 319 patients were analyzed, of whom 5 (1.6%) were DCD. HLTx volume increased from 2013 to 2023 (p < 0.001). One- and 5-year survival following HLTx was 84.0% and 59.5%, respectively. One-year survival was higher for patients undergoing HLTx at a high-volume center (88.3% vs. 77.9%; p = 0.012). After risk adjustment, extracorporeal membrane oxygenation support 72 h posttransplant and predischarge dialysis were associated with increased 1-year mortality (HR = 3.19, 95% CI = 1.86-5.49 and HR = 3.47, 95% CI = 2.17-5.54, respectively) and 5-year mortality (HR = 2.901, 95% CI = 1.679-5.011 and HR = 3.327, 95% CI = 2.085-5.311, respectively), but HLTx at a high-volume center was not associated with either. CONCLUSIONS: HLTx volume has resurged, with DCD HLTx emerging as a viable procurement strategy. Factors associated with 1- and 5-year survival may be used to guide postoperative management following HLTx.

Education in the National Transplant Law as an ethical pathway for the construction of the health care value in Colombia / La enseñanza de la Ley Nacional de Trasplante como camino ético para la construcción del valor de la atención en salud en Colombia.

The national transplant law in Colombia, Law 1805 of 2016, modified the Colombian legislation regarding how a person accesses an organ transplant, but above all, it changed the donor figure, establishing the term derived from the presumptive consent right. This term implies a person's hypothetical willingness to be an organ donor as a manifestation of solidarity and charity towards another person in a situation of need and vulnerability concerning his/her health and the dimensions that define it. In the following text, seven moments are considered fundamental facts when constructing a culture about the value of healthcare in the national transplant policy in Colombia.

La Ley Nacional de Trasplantes en Colombia, Ley 1805 de 2016, modificó la legislación colombiana en cuanto a cómo se accede a un trasplante de órganos, pero, sobre todo, cambió la figura de donatario y dispuso el término derivado del derecho del consentimiento presuntivo. Este define la hipotética voluntad de una persona de ser donante de órganos como manifestación de solidaridad y beneficencia con otra persona en situación de necesidad y vulnerabilidad relacionada con su salud y las dimensiones que la definen. En el siguiente texto se presentan siete momentos que se consideran hechos fundamentales en la construcción de una cultura del valor de la atención en salud en la política nacional de trasplantes de Colombia.

The current landscape of in situ and ex-situ machine perfusion utilization for liver grafts from cardiac donation after circulatory death donors in the US.

Donation after circulatory death (DCD) is driving the increase in deceased organ donors in the United States. Normothermic regional perfusion (NRP) and ex-situ machine perfusion (es-MP) have been instrumental in improving liver transplant outcomes and graft utilization. This study examines the current landscape of liver utilization from cardiac DCD donors in the US. Using the UNOS STAR file, all adult (≥ 18 years old) DCD donors in the US in which the heart was used for transplantation from October 1, 2020, to September 30, 2023, were compared using procurement technique (NRP versus super rapid recovery [SRR]) and storage strategy (es-MP versus static cold storage [SCS]). 188 livers were transplanted from 309 TA-NRP donors (61% utilization) versus 305 (56%) liver transplants from 544 SRR donors. Es-MP was used in 20% (n= 38) of NRP cases versus 32% (98) of SRR cases. 281 (59%) of liver grafts were exposed to NRP, es-MP, or both. While there is widespread utilization of machine perfusion, more research is needed to determine optimal graft management strategies, particularly concerning the use of multiple technologies in complementary ways. More complete data collection is necessary at a national level to address these important research questions.

Durable left ventricular assist devices as a bridge to transplantation: what to expect along the way?

INTRODUCTION: The scarcity of donors coupled with the improvements in left ventricular assist devices (LVAD) technology has led to the use of LVAD as a bridge to transplantation (BTT). AREAS COVERED: The authors provide an overview of the current status of LVAD BTT implantation with special focus ranging from patient selection and pre-implantation optimization to post-transplant outcomes. EXPERT OPINION: The United Network for Organ Sharing 2018 policy amendment resulted in a significant reduction in the number of LVADs used for BTT in the US. To overcome this issue, modifications in the US allocation policy to consider factors such as days on device support, age, and type of complications may be necessary to potentially increase implantation rates.

Assessing the Brain Death/Death by Neurologic Criteria Determination Process in Korea: Insights from 10-Year Noncompleted Donation Data.

BACKGROUND: This study aimed to analyze the current status of brain death/death by neurologic criteria (BD/DNC) determination in Korea over a decade, identifying key areas for improvement in the process. METHODS: We conducted a retrospective analysis of data from the Korea Organ Donation Agency spanning 2011 to 2021, focusing on donors whose donations were not completed. The study reviewed demographics, medical settings, diagnoses, and outcomes, with particular emphasis on cases classified as nonbrain death and those resulting in death by cardiac arrest during the BD/DNC assessment. RESULTS: Of the 5047 patients evaluated for potential brain death from 2011 to 2021, 361 were identified as noncompleted donors. The primary reasons for noncompletion included nonbrain death (n = 68, 18.8%), cardiac arrests during the BD/DNC assessment process (n = 80, 22.2%), organ ineligibility (n = 151, 41.8%), and logistical and legal challenges (n = 62, 17.2%). Notably, 25 (36.8%) of them failed to meet the minimum clinical criteria, and 7 of them were potential cases of disagreement between the two clinical examinations. Additionally, most cardiac arrests (n = 44, 55.0%) occurred between the first and second examinations, indicating management challenges in critically ill patients during the assessment period. CONCLUSIONS: Our study highlights significant challenges in the BD/DNC determination process, including the need for improved consistency in neurologic examinations and the management of critically ill patients. The study underscores the importance of refining protocols and training to enhance the accuracy and reliability of brain death assessments, while also ensuring streamlined and effective organ donation practices.

Potential for organ donation after controlled circulatory death: a retrospective analysis.

Objectives: Despite the discrepancy between demand and availability of organs for transplantation, controlled circulatory death donation has not been implemented in Portugal. This study aimed to estimate the potential increase in organ donation from implementing such a program. Material and Methods: All deceased patients within the intensive care medicine department at Centro Hospitalar Universitário de São João, throughout the year 2019, were subjected to retrospective analysis. Potential gain was estimated comparing the results with the number of donors and organs collected during the same period at this hospital center. Differences in variables between groups were assessed using t tests for independent samples or Mann-Whitney U tests for continuous variables, and chi-squared tests were used for categorical variables. Results: During 2019, 152 deaths occurred after withdrawal of life-sustaining therapies, 10 of which would have been potentially eligible for donation after controlled circulatory death. We can anticipate a potential increase of 10 prospective donors, a maximum 21% growth in yearly transplantation activity, with a greater impact on kidney transplantation. For most patients, the time between withdrawal of organ support and death surpassed 120 minutes, an outcome explained by variations in withdrawal of life-sustaining measures and insufficient clinical records, underestimating the potential for controlled circulatory arrest donation. Conclusion: This study effectively highlights public health benefits of controlled circulatory arrest donation. Legislation allowing donation through this method represents a social gain and enables patients who will never meet brain death criteria to donate organs as part of the end-of-life process in intensive care medicine, within a framework of complete ethical alignment.

Comparative Analysis of Ischemia-Reperfusion Injury in Heart Transplantation: A Single-Center Study Evaluating Conventional Ice-Cold Storage versus the Paragonix SherpaPak Cardiac Transport System.

BACKGROUND: Since the 2018 allocation system change in heart transplantation (HT), ischemic times have increased, which may be associated with peri-operative and post-operative complications. This study aimed to compare ischemia reperfusion injury (IRI) in hearts preserved using ice-cold storage (ICS) and the Paragonix SherpaPak TM Cardiac Transport System (CTS). METHODS: From January 2021 to June 2022, consecutive endomyocardial biopsies from 90 HT recipients were analyzed by a cardiac pathologist in a single-blinded manner: 33 ICS and 57 CTS. Endomyocardial biopsies were performed at three-time intervals post-HT, and the severity of IRI manifesting histologically as coagulative myocyte necrosis (CMN) was evaluated, along with graft rejection and graft function. RESULTS: The incidence of IRI at weeks 1, 4, and 8 post-HT were similar between the ICS and CTS groups. There was a 59.3% statistically significant reduction in CMN from week 1 to 4 with CTS, but not with ICS. By week 8, there were significant reductions in CMN in both groups. Only 1 out of 33 (3%) patients in the ICS group had an ischemic time >240 mins, compared to 10 out of 52 (19%) patients in the CTS group. During the follow-up period of 8 weeks to 12 months, there were no significant differences in rejection rates, formation of de novo donor-specific antibodies and overall survival between the groups. CONCLUSION: The CTS preservation system had similar rates of IRI and clinical outcomes compared to ICS despite longer overall ischemic times. There is significantly more recovery of IRI in the early post operative period with CTS. This study supports CTS as a viable option for preservation from remote locations, expanding the donor pool.

The best option argument and kidney sales: a reply to Albertsen.

In a recent article, Albertsen both elaborates the best option argument for regulated markets and levels a justice-based objection to kidney sales. In the present article, I show that Albertsen has crucially misunderstood the best option argument. It is not a defence of kidney sales, as Albertsen claims. It is a reply to an objection. The objection, perennial in the debate, opposes kidney sales on the grounds that sellers would be harmed. The best option argument-proving that prohibitions tend to set back the interests of those denied their preferred option-shows this thinking to be confused. If sound, the best option argument dramatically undercuts any attempt to oppose a market citing would-be sellers' interests.

Pass the tissue: restoring researcher access to legal human donations.

The sensitivity of human tissue and previous instances of misuse have, rightfully, led to the introduction of far-reaching oversight and regulatory mechanisms for accessing, storing and sharing samples. However, these restrictions, in tandem with more broad-based privacy regulations, have had the unintended consequence of obstructing legitimate requests for medical materials. This is of real detriment to ambitions for biomedical research, most notably the precision medicine agenda. As such, this paper makes the case for facilitating authorised researcher access to human tissue and associated data along practical medical ethics lines, detailing how liberating samples from unfit regulations, re-evaluating biobanks, diversifying considerations for donor benefit-risk, future proofing donor consent and flattening hierarchies of donation acceptability equate to a more cohesive and respectful means of managing biological samples and information than is achieved at present.

Development of an improved Scientific Registry of Transplant Recipients deceased donor heart yield model using donor critical care data from the Donor Management Goal Registry cohort.

Organ procurement organizations (OPOs) face increasing regulatory scrutiny, and the performance of predictive models used to assess OPO performance is critical. We sought to determine whether adding deceased donor physiological and critical care data to the existing Scientific Registry of Transplant Recipients (SRTR) heart yield model would improve the model's performance. Donor data and heart transplanted (yes/no), the outcome of interest, were obtained from the United Network for Organ Sharing Donor Management Goal (DMG) Registry for 19 141 donors after brain death, from 25 OPOs. The data were split into training and testing portions. Multivariable LASSO regression was used to develop a statistical model incorporating DMG data elements with the existing components of the SRTR model. The DMG + SRTR and SRTR models were applied to the test data to compare the predictive performance of the models. The sensitivity (84%-86%) and specificity (84%-86%) were higher for the DMG + SRTR model compared to the SRTR model (71%-75% and 76%-77%, respectively). For the DMG + SRTR model, the C-statistic was 0.92 to 0.93 compared to 0.80 to 0.81 for the SRTR model. DMG data elements improve the predictive performance of the heart yield model. The addition of DMG data elements to the Organ Procurement and Transplantation Network data collection requirements should be considered.