Standardized deceased donor kidney donation rates in the UK reveal marked regional variation and highlight the potential for increasing kidney donation: a prospective cohort study†

Factors influencing deceased organ donation rates in OECD countries: a panel data analysis

OBJECTIVES

This study aims to investigate factors with a significant influence on deceased organ donation rates in Organisation for Economic Co-operation and Development (OECD) countries and determine their relative importance. It seeks to provide the necessary data to facilitate the development of more efficient strategies for improving deceased organ donation rates.

DESIGN

Retrospective study.

SETTING

Publicly available secondary annual data.

PARTICIPANTS

The study includes 36 OECD countries as panel members for data analysis.

OUTCOME MEASURES

Multivariable panel data regression analysis was employed, encompassing data from 2010 to 2018 for all investigated variables in the included countries.

RESULTS

The following variables had a significant influence on deceased organ donation rates: 'opt-in' system (β=-4.734, p<0.001, ref: 'opt-out' system), only donation after brain death (DBD) donors allowed (β=-4.049, p=0.002, ref: both DBD and donation after circulatory death (DCD) donors allowed), number of hospital beds per million population (pmp) (β=0.002, p<0.001), total healthcare employment pmp (β=-0.00012, p=0.012), World Giving Index (β=0.124, p=0.008), total tax revenue as a percentage of gross domestic product (β=0.312, p=0.009) and percentage of population aged ≥65 years (β=0.801, p<0.001) as well as high education population in percentage (β=0.118, p=0.017).

CONCLUSIONS

Compared with the promotion of socioeconomic factors with a positive significant impact on deceased organ donation rates, the following policies have been shown to significantly increase rates of deceased organ donation, which could be further actively promoted: the adoption of an 'opt-out' system with presumed consent for deceased organ donation and the legal authorisation of both DBD and DCD for transplantation.

Donor audits in deceased organ donation: a scoping review

PURPOSE

We sought to collate and summarize existing literature on donor audits (DA) and how they have been used to guide deceased organ donation and transplantation system performance and quality assurance.

SOURCE

We searched MEDLINE, Cumulative Index of Nursing and Allied Health Literature, and Web of Science supplemented by Google to identify grey literature on 6 May 2022, to locate studies in English, French, and Spanish. The data were screened, extracted, and analyzed independently by two reviewers. We grouped the results into five categories: 1) motivation for DA, 2) DA methodology, 3) potential and actual donors, 4) missed donation opportunities, and 5) quality improvement.

PRINCIPAL FINDINGS

The search yielded 2,416 unique publications and 52 were included in this review. Most studies were from the UK (n = 13) and published between 2001 and 2006 (n = 15). The methodologies described for DA were diverse. Our findings showed that the primary motivation for conducting DA was to identify potential donors and the number of potential deceased organ donors is significantly higher than the number of actual donors. Among retrieved studies, the proportion of donation opportunities following neurologic determination of death was 95/222 (43%) compared with 25/181 (14%) for donation after cardiocirculatory death (DCD), suggesting that the missed donation rate is higher for DCD.

CONCLUSION

Donor audits help identify missed donation opportunities along the deceased donation pathway and can help support the evaluation of quality improvement initiatives.

Renal transplantation during the SARS-CoV-2 pandemic in the UK: Experience from a large-volume center

There is uncertainty about the safety of kidney transplantation during the SARS-CoV-2 pandemic due to the risk of donor transmission, nosocomial infection and immunosuppression use. We describe organ donation and transplant practice in the UK and assess whether kidney transplantation conferred a substantial risk of harm. Data from the UK transplant registry were used to describe kidney donation and transplant activity in the UK, and a detailed analysis of short-term, single-center, patient results in two periods: during the pre-pandemic era from 30th December 2019 to 8th March 2020 ("Pre-COVID era") and the 9th March 2020 to 19th May 2020 ("COVID era"). Donor and recipient numbers fell by more than half in the COVID compared to the pre-COVID era in the UK, but there were more kidney transplants performed in our center (42 vs. 29 COVID vs. pre-COVID respectively). Overall outcomes, including re-operation, delayed graft function, primary non-function, acute rejection, length of stay and graft survival were similar between COVID and pre-COVID era. 6/71 patients became infected with SARS-CoV-2 but all were discharged without critical care requirement. Transplant outcomes have remained similar within the COVID period and no serious sequelae of SARS-CoV-2 infection were observed in the peri-transplant period.

Solid organ donation from the emergency department - A systematic review

OBJECTIVES

A significant gap exists between people awaiting an organ transplant and organ donors. The purpose of this study was to determine what percent of successful donors come from the emergency department (ED), whether there are any missed donors, and to identify factors associated with successful and missed donation.

METHODS

This systematic review used electronic searches of EMBASE, MEDLINE, and CINAHL according to PRISMA guidelines on July 7, 2017. We included primary literature in adults describing successful and missed organ donation. Two authors independently screened articles, and discrepancies were resolved through consensus. Quality was assessed using the STROBE checklist.

RESULTS

This systematic review identified 1,058 articles, and 25 articles were included. For neurologic determination of death, ED patients comprised 4%-50% of successful donors and 3.6%-8.9% of successful donors for donation after circulatory determination of death. ED death reviews revealed up to 84% of missed neurologic determination of death, and 46.2% of missed circulatory determination of death donors who died in the ED are missed due to a failure to refer for consideration of organ donation. Clinical heterogeneity precluded pooling of the data to conduct a meta-analysis.

CONCLUSIONS

The ED is a source of actual and missed donors. Potential donors are often missed due to incorrect assumptions regarding eligibility criteria and failure of the healthcare team to refer for consideration of donation. ED healthcare professionals should be aware of organ donation referral protocols at their institution to ensure that no organ donors are missed.

PreImplantation Trial of Histopathology In renal Allografts (PITHIA): a stepped-wedge cluster randomised controlled trial protocol

INTRODUCTION

Most potential kidney transplant donors in the UK are aged over 60 years, yet increasing donor age is associated with poorer graft survival and function. Urgent preimplantation kidney biopsy can identify chronic injury, and may aid selection of better 'quality' kidneys from this group. However, the impact of biopsy on transplant numbers remains unproven. The PreImplantation Trial of Histopathology In renal Allografts (PITHIA) study will assess whether the introduction of a national, 24 hours, digital histopathology service increases the number, and improves outcomes, of kidneys transplanted in the UK from older deceased donors.

METHODS AND ANALYSIS

PITHIA is an open, multicentre, stepped-wedge cluster randomised study, involving all UK adult kidney transplant centres. At 4-monthly intervals, a group of 4-5 randomly selected clusters (transplant centres) will be given access to remote, urgent, digital histopathology (total intervention period, 24 months). The trial has two primary end points: it is powered for an 11% increase in the proportion of primary kidney offers from deceased donors aged over 60 years that are transplanted, and a 6 mL/min increase in the estimated glomerular filtration rate of recipients at 12 months post-transplant. This would equate to an additional 120 kidney transplants performed in the UK annually. Trial outcome data will be collected centrally via the UK Transplant Registry held by NHS Blood and Transplant (NHSBT) and will be analysed using mixed effects models allowing for clustering within centres and adjusting for secular trends. An accompanying economic evaluation will estimate the cost-effectiveness of the service to the National Health Service.

ETHICS AND DISSEMINATION

The study has been given favourable ethical opinion by the Cambridge South Research Ethics Committee and is approved by the Health Research Authority. We will present our findings at key transplant meetings, publish results within 4 years of the trial commencing and support volunteers at renal patient groups to disseminate the trial outcome.

TRIAL REGISTRATION NUMBER

ISRCTN11708741; Pre-results.

Local Expansion of Donation After Circulatory Death Kidney Transplant Activity Improves Waitlisted Outcomes and Addresses Inequities of Access to Transplantation

In the United Kingdom, donation after circulatory death (DCD) kidney transplant activity has increased rapidly, but marked regional variation persists. We report how increased DCD kidney transplant activity influenced waitlisted outcomes for a single center. Between 2002-2003 and 2011-2012, 430 (54%) DCD and 361 (46%) donation after brain death (DBD) kidney-only transplants were performed at the Cambridge Transplant Centre, with a higher proportion of DCD donors fulfilling expanded criteria status (41% DCD vs. 32% DBD; p = 0.01). Compared with U.K. outcomes, for which the proportion of DCD:DBD kidney transplants performed is lower (25%; p < 0.0001), listed patients at our center waited less time for transplantation (645 vs. 1045 days; p < 0.0001), and our center had higher transplantation rates and lower numbers of waiting list deaths. This was most apparent for older patients (aged >65 years; waiting time 730 vs. 1357 days nationally; p < 0.001), who received predominantly DCD kidneys from older donors (mean donor age 64 years), whereas younger recipients received equal proportions of living donor, DBD and DCD kidney transplants. Death-censored kidney graft survival was nevertheless comparable for younger and older recipients, although transplantation conferred a survival benefit from listing for only younger recipients. Local expansion in DCD kidney transplant activity improves survival outcomes for younger patients and addresses inequity of access to transplantation for older recipients.

Attitudes and beliefs about deceased organ donation in the Arabic-speaking community in Australia: a focus group study

OBJECTIVES

To describe the beliefs and attitudes to organ donation in the Arabic-speaking community.

DESIGN

Arabic-speaking participants were purposively recruited to participate in 6 focus groups. Transcripts were analysed thematically.

PARTICIPANTS

53 participants, aged 19-77 years, and originating from 8 countries, participated in 1 of 6 focus groups. Participants identified as Christian (73%), Islam (26%), Buddhist (2%) or did not identify with any religion (2%).

RESULTS

6 themes (with subthemes) were identified; religious conviction; invisibility of organ donation; medical suspicion; owning the decision; and reciprocal benefit.

CONCLUSIONS

Although organ donation is considered a generous life-saving 'gift', representative members of the Arabic-speaking community in Australia were unfamiliar with, unnerved by and sceptical about the donation process. Making positive decisions about organ donation would likely require resolving tensions between respecting family, community and religious values versus their individual autonomy. Providing targeted education about the process and benefits of organ donation within the Arabic community may clarify ambiguities surrounding cultural and religious-based views on organ donation, reduce taboos and suspicion towards donation, and in turn, lead to increased organ donation rates.

Kidney donation after circulatory death (DCD): state of the art

The use of kidneys from controlled donation after circulatory death (DCD) donors has the potential to markedly increase kidney transplants performed. However, this potential is not being realized because of concerns that DCD kidneys are inferior to those from donation after brain-death (DBD) donors. The United Kingdom has developed a large and successful controlled DCD kidney transplant program that has allowed for a substantial increase in kidney transplant numbers. Here we describe recent trends in DCD kidney donor activity in the United Kingdom, outline aspects of the donation process, and describe donor selection and allocation of DCD kidneys. Previous UK Transplant Registry analyses have shown that while DCD kidneys are more susceptible to cold ischemic injury and have a higher incidence of delayed graft function, short- and medium-term transplant outcomes are similar in recipients of kidneys from DCD and DBD donors. We present an updated, extended UK registry analysis showing that longer-term transplant outcomes in DCD donor kidneys are also similar to those for DBD donor kidneys, and that transplant outcomes for kidneys from expanded-criteria DCD donors are no less favorable than for expanded-criteria DBD donors. Accordingly, the selection criteria for use of kidneys from DCD donors should be the same as those used for DBD donors. The UK experience suggests that wider international development of DCD kidney transplantation programs will help address the global shortage of deceased donor kidneys for transplantation.

Kidney donation after circulatory death (DCD): state of the art

Ischemia–reperfusion (IR) injury to the kidney occurs in a range of clinically important scenarios including hypotension, sepsis and in surgical procedures such as cardiac bypass surgery and kidney transplantation, leading to acute kidney injury (AKI). Mitochondrial oxidative damage is a significant contributor to the early phases of IR injury and may initiate a damaging inflammatory response. Here we assessed whether the mitochondria targeted antioxidant MitoQ could decrease oxidative damage during IR injury and thereby protect kidney function. To do this we exposed kidneys in mice to in vivo ischemia by bilaterally occluding the renal vessels followed by reperfusion for up to 24 h. This caused renal dysfunction, measured by decreased creatinine clearance, and increased markers of oxidative damage. Administering MitoQ to the mice intravenously 15 min prior to ischemia protected the kidney from damage and dysfunction. These data indicate that mitochondrial oxidative damage contributes to kidney IR injury and that mitochondria targeted antioxidants such as MitoQ are potential therapies for renal dysfunction due to IR injury.

Baseline donor chronic renal injury confers the same transplant survival disadvantage for DCD and DBD kidneys

Histological assessment of baseline chronic kidney injury may discriminate kidneys that are suitable for transplantation, but has not been validated for appraisal of donation after circulatory death (DCD) kidneys. 'Time-zero' biopsies for 371 consecutive, solitary, deceased-donor kidneys transplanted at our center between 2006 and 2010 (65.5% DCD, 34.5% donation after brain death [DBD]) were reviewed and baseline chronic degenerative injury scored using Remuzzi's classification. High scores correlated with donor age and extended criteria donors (42% of donors), but the spectrum of scores was similar for DCD and DBD kidneys. Transplant outcomes for kidneys scoring from 0 to 4 were comparable (1 and 3 year graft survival 95% and 92%), but were much poorer for kidneys scoring ≥5, with 1 year graft survival only 73%, and 12.5% suffering primary nonfunction. Critically, high Remuzzi scores conferred the same survival disadvantage for DCD and DBD kidneys. On multi-variable regression analysis, time-zero biopsy score was the only independent predictor for graft survival, whereas one-year graft estimated glomerular filtration rate (eGFR) correlated with donor age and biopsy score. In conclusion, the relationship between severity of chronic kidney injury and transplant outcome is similar for DCD and DBD kidneys. Kidneys with Remuzzi scores of ≤4 can be implanted singly with acceptable results.