Deceased organ donor research: the last research frontier?

Research and Innovation in Organ Donation: Recommendations From an International Consensus Forum

This report provides recommendations from the Research and Innovation domain as part of the International Donation and Transplantation Legislative and Policy Forum (hereafter the Forum) to provide expert guidance on the structure of an ideal organ and tissue donation and transplantation system. The recommendations focus on deceased donation research and are intended for clinicians, investigators, decision-makers, and patient, family, and donor (PFD) partners involved in the field.

Methods

We identified topics impacting donation research through consensus using nominal group technique. Members performed narrative reviews and synthesized current knowledge on each topic, which included academic articles, policy documents, and gray literature. Using the nominal group technique, committee members discussed significant findings, which provided evidence for our recommendations. The Forum's scientific committee then vetted recommendations.

Results

We developed 16 recommendations in 3 key areas to provide stakeholders guidance in developing a robust deceased donor research framework. These include PFD and public involvement in research; donor, surrogate, and recipient consent within a research ethics framework; and data management. We highlight the importance of PFD and public partner involvement in research, we define the minimum ethical requirements for the protection of donors and recipients of both target and nontarget organ recipients, and we recommend the creation of a centrally administered donor research oversight committee, a single specialist institutional review board, and a research oversight body to facilitate coordination and ethical oversight of organ donor intervention research.

Conclusions

Our recommendations provide a roadmap for developing and implementing an ethical deceased donation research framework that continually builds public trust. Although these recommendations can be applied to jurisdictions developing or reforming their organ and tissue donation and transplantation system, stakeholders are encouraged to collaborate and respond to their specific jurisdictional needs related to organ and tissue shortages.

Challenges encountered in conducting donor-based research: Lessons learned from the Donor Heart Study

Solid organ transplantation continues to be constrained by a lack of suitable donor organs. Advances in donor management and evaluation are needed to address this shortage, but the performance of research studies in deceased donors is fraught with challenges. Here we discuss several of the major obstacles we faced in the conduct of the Donor Heart Study-a prospective, multi-site, observational study of donor management, evaluation, and acceptance for heart transplantation. These included recruitment and engagement of participating organ procurement organizations, ambiguities related to study oversight, obtaining authorization for donor research, logistical challenges encountered during donor management, sustaining study momentum, and challenges related to study data management. By highlighting these obstacles encountered, as well as the solutions implemented, we hope to stimulate further discussion and actions that will facilitate the design and execution of future donor research studies.

How to Preserve Liver Grafts From Circulatory Death With Long Warm Ischemia? A Retrospective Italian Cohort Study With Normothermic Regional Perfusion and Hypothermic Oxygenated Perfusion

BACKGROUND

Donation after circulatory death (DCD) in Italy, given its 20-min stand-off period, provides a unique bench test for normothermic regional perfusion (NRP) and dual hypothermic oxygenated machine perfusion (D-HOPE).

METHODS

We coordinated a multicenter retrospective Italian cohort study with 44 controlled DCD donors, who underwent NRP, to present transplant characteristics and results. To rank our results according to the high donor risk, we matched and compared a subgroup of 37 controlled DCD livers, preserved with NRP and D-HOPE, with static-preserved controlled DCD transplants from an established European program.

RESULTS

In the Italian cohort, D-HOPE was used in 84% of cases, and the primary nonfunction rate was 5%. Compared with the matched comparator group, the NRP + D-HOPE group showed a lower incidence of moderate and severe acute kidney injury (stage 2: 8% versus 27% and stage 3: 3% versus 27%; P = 0.001). Ischemic cholangiopathy remained low (2-y proportion free: 97% versus 92%; P = 0.317), despite the high-risk profile resulting from the longer donor warm ischemia in Italy (40 versus 18 min; P < 0.001).

CONCLUSIONS

These data suggest that NRP and D-HOPE yield good results in DCD livers with prolonged warm ischemia.

Association between longer hospitalization and development of de novo donor specific antibodies in simultaneous liver-kidney transplant recipients

Background: De novo Donor Specific Antibodies (DSA) are considered as a risk factor for the kidney allograft outcomes in recipients after simultaneous liver-kidney transplantation (SLKT). We hypothesized that length of hospital stay (LOS) might be associated with de novo DSA development of due to the increased likelihood of receiving blood transfusions with reduced immunosuppressive regimens.Methods: This study is a single-center, retrospective cohort study consisting of 85 recipients who underwent SLKT from 2009 to 2018 in our hospital. We divided the patients into two groups according to LOS [long hospital stay (L) group (LOS >14 days) and short hospital stay (S) group (LOS ≤14 days)]. Propensity score (PS) has been created using logistic regression to predict LOS greater than median of 14 days. The association between the presence of de novo DSA and LOS was assessed by logistic regression models adjusted for PS.Results: The mean age at transplantation of the entire cohort was 55.5 ± 10.1 years. Sixty percent of the recipients were male and Caucasian. Median LOS in (L) group was three-fold longer than (S) group [L: median 30 days (IQR: 21-52), S: median 8.5 days (IQR: 7-11)]. Eight patients developed de novo DSA after SLKT (9.4%), all of them were in (L) group. Longer LOS was significantly associated with higher risk of development of de novo DSA in unadjusted (OR_{+ each 5 days}: 1.09, 95% CI:1.02-1.16) and PS adjusted (OR_{+ each 5 days}: 1.11, 95% CI:1.02-1.21) analysis.Conclusion: Longer hospitalization is significantly associated with the development of de novo DSA in SLKT.

Deceased donor organ procurement injuries in the United States

AIM: To determine the incidence of surgical injury during deceased donor organ procurements.

METHODS: Organ damage was classified into three tiers, from 1-3, with the latter rendering the organ non-transplantable. For 12 consecutive months starting in January of 2014, 36 of 58 organ procurement organization’s (OPO)’s prospectively submitted quality data regarding organ damage (as reported by the transplanting surgeon and confirmed by the OPO medical director) seen on the procured organ.

RESULTS: These 36 OPOs recovered 5401 of the nations’s 8504 deceased donors for calendar year 2014. A total of 19043 organs procured were prospectively analyzed. Of this total, 59 organs sustained damage making them non-transplantable (0 intestines; 4 pancreata; 5 lungs; 6 livers; 43 kidneys). The class 3 damage was spread over 22 (of 36) reporting OPO’s.

CONCLUSION: While damage to the procured organ is rare with organ loss being approximately 0.3% of procured organs, loss of potential transplantable organs does occur during procurement.

Therapeutic Hypothermia in Deceased Organ Donors and Kidney-Graft Function

BACKGROUND

Delayed graft function, which is reported in up to 50% of kidney-transplant recipients, is associated with increased costs and diminished long-term graft function. The effect that targeted mild hypothermia in organ donors before organ recovery has on the rate of delayed graft function is unclear.

METHODS

We enrolled organ donors (after declaration of death according to neurologic criteria) from two large donation service areas and randomly assigned them to one of two targeted temperature ranges: 34 to 35°C (hypothermia) or 36.5 to 37.5°C (normothermia). Temperature protocols, which were initiated after authorization was obtained for the organ to be donated and for the donor's participation in the study, ended when organ donors left the intensive care unit for organ recovery in the operating room. The primary outcome was delayed graft function in the kidney recipients, which was defined as the requirement for dialysis during the first week after transplantation. Secondary outcomes were the rates of individual organs transplanted in each treatment group and the total number of organs transplanted from each donor.

RESULTS

The study was terminated early, on the recommendation of an independent data and safety monitoring board, after the interim analysis showed efficacy of hypothermia. At trial termination, 370 organ donors had been enrolled (180 in the hypothermia group and 190 in the normothermia group). A total of 572 patients received a kidney transplant (285 kidneys from donors in the hypothermia group and 287 kidneys from donors in the normothermia group). Delayed graft function developed in 79 recipients of kidneys from donors in the hypothermia group (28%) and in 112 recipients of kidneys from donors in the normothermia group (39%) (odds ratio, 0.62; 95% confidence interval, 0.43 to 0.92; P=0.02).

CONCLUSIONS

Mild hypothermia, as compared with normothermia, in organ donors after declaration of death according to neurologic criteria significantly reduced the rate of delayed graft function among recipients. (Funded by the Health Resources and Services Administration; ClinicalTrials.gov number, NCT01680744.).

Current research on organ donor management

A shortage of organs is available for transplantation, with 116,000 patients on the Organ Procurement and Transplantation Network/United Network for Organ Sharing wait list. Because the demand for organs outweighs the supply, considerable care must be taken to maximize the number of organs transplanted per donor and optimize the quality of recovered organs. Studies designed to determine optimal donor management therapies are limited, and this research has many challenges. Although evidenced-based guidelines for managing potential organ donors do not exist, research in this area is increasing. This article reviews the existing literature and highlights recent trials that can guide management.