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Organ donation networks audit and report on national or regional organ donation performance, however there are inconsistencies in the metrics and definitions used, rendering comparisons difficult or inappropriate. This is despite multiple attempts exploring the possibility for convergently evolving audits so that collectives of donation networks might transparently share data and practice and then target system interventions. This paper represents a collaboration between the United Kingdom and Australian organ donation organisations which aimed to understand the intricacies of our respective auditing systems, compare the metrics and definitions they employ and ultimately assess their level of comparability. This point of view outlines the historical context underlying the development of the auditing tools, demonstrates their differences to the Critical Pathway proposed as a common tool a decade ago and presents a side-by-side comparison of donation definitions, metrics and data for the 2019 calendar year. There were significant differences in donation definition terminology, metrics and overall structure of the audits. Fitting the audits to a tiered scaffold allowed for reasonable comparisons however this required substantial effort and understanding of nuance. Direct comparison of international and inter-regional donation performance is challenging and would benefit from consistent auditing processes across organisations.
Organ transplantation is a lifesaving, life-transforming intervention which often is the only effective treatment available to patients with end-stage organ failure. Such patients rely on a limited supply of organs and experience high mortality and significant morbidity whilst waitlisted (
Meaningful comparison of national/regional donation metrics might allow for sharing of best practice and overall improvement of donation performance. Countries with low conversion rates could learn from practices of countries with better performance (
The “Critical Pathway for Deceased Donation,” the outcome of a multi-national initiative held between 2008–10, was aimed to provide a solution to this issue by providing a set of common definitions to guide consistency in reporting of donation performance (
The critical pathway for deceased donation was developed by a multi-national collective at the Madrid Resolution on Organ Donation and Transplantation (
Inclusion in the “possible deceased organ donor” pool is defined by the critical pathway as “A patient with devastating brain injury or lesion or a patient with circulatory failure and apparently medically suitable for organ donation”(
Critical pathway for deceased donation definitions—adapted from Dominguez et al. (2011)
Common term | DBD component | DCD component |
---|---|---|
Potential | Potential DBD donor: A person whose clinical condition is suspected to fulfil brain death criteria | Potential DCD donor: |
A. A person whose circulator and respiratory functions have ceased and resuscitative measures are not to be attempted or continued, or | ||
B. A person in whom the cessation of circulatory and respiratory functions is anticipated to occur within a time frame that will enable organ recovery | ||
Eligible | Eligible DBD donor: A medically suitable person who has been declared dead based on neurological criteria as stipulated by the law of the relevant jurisdiction | Eligible DCD donor: A medically suitable person who has been declared dead based on the irreversible absence of circulatory and respiratory functions as stipulated by the law of the relevant jurisdiction, within a time frame that enables organ recovery |
Actual | Actual DBD donor: A consented eligible donor: | Actual DCD donor: A consented eligible donor: |
A. In whom an operative incision was made with the intent of organ recovery for the purpose of transplantation, or | A. In whom an operative incision was made with the intent of organ recovery for the purpose of transplantation, or | |
B. From whom at least one organ was recovered for the purpose of transplantation | B. From whom at least one organ was recovered for the purpose of transplantation | |
Utilised | Utilised DBD donor: An actual donor from whom at least one organ was transplanted | Utilised DCD donor: An actual donor from whom at least one organ was transplanted |
The development of the potential donor audit (PDA) in the UK followed the publication of a study auditing DBD potential in intensive care units (ICUs) which estimated a possible 20% increase in deceased kidney donation based on prompt testing for brain stem death (
Early audits of hospital deaths occurred in several states in Australia with the aim of quantifying the potential for organ donation, focusing on identifying missed donor cases (
Over 2020–2021, we conducted a series of virtual meetings aiming to compare national methods, definitions and metrics used for data collection and reporting of national deceased donation performance. Tables were created outlining the definitions used in DBD and DCD pathways set out by the “Critical Pathway for Deceased Donation” (
General differences between the auditing structures were immediately apparent (
Differences in audited deaths included in the UK and Australian donation audits.
United Kingdom | Australia | |
---|---|---|
Inclusion criteria | Deaths under 80 years old occurring in intensive care OR emergency department (excluding deaths in neonatal ICU) | Deaths under 80 years old or >28 days old occurring in intensive care or emergency departments OR occurring anywhere in hospital within 24 h of presence in intensive care OR emergency department where irrecoverable brain injury present. Additional inclusion of patients >80 yr if formal request for consideration of donation placed by family and donation considered feasible by attending staff |
Data pathway structure | DBD and DCD data audited separately | DBD and DCD data combined in audit |
Network Organisation | National, centralised service: “Statistics and Clinical Research department, NHS Blood and Transplant” | National, centralised service: the “Organ and Tissue Authority” (OTA) which maintains a web-based auditing tool capturing approx. 98% of deceased donation activity in Australia |
Data Collection and input | Specialist Nurses in Organ Donation embedded in individual hospitals | Nurse donation specialists embedded in individual hospitals or through outreach roles in smaller hospitals without permanent embedded staff |
The basic structure of the audit also differed. In the UK, when DBD and DCD cases are audited they feed into separate streams of data collection (similar to the Critical Pathway) whereas in Australia these streams are combined (
Structure of donation performance audits in the UK (left) and Australia (right). *Not publicly available, **refers to “Actual donors: DCD,” a small subset of those who are brain dead who enter a DCD pathway by specific request of family.
Despite some differences in terminology used between countries, both audits could be fitted to seven major tiers (
Specific differences in the UK and Australian donation audits.
Tier | UK—DBD | UK—DCD | Australia | Comments |
---|---|---|---|---|
2 | “Potential DBD donor” | “Potential DCD donor” | “End-of-life care pool” | -Differing terms |
A patient who meets all four criteria (coma, ventilated, fixed pupils, apnoeic) for neurological death testing excluding those not tested due to reasons “cardiac arrest despite resuscitation,” “brainstem reflexes returned,” “neonates—less than 2 months post term” | A patient who had treatment withdrawn and death was anticipated within 4 hours | Any patient who meets the following criteria:-Confirmed or suspected brain death-Withdrawal of one or more of mechanical ventilation, artificial airway, mechanical circulatory support prior to death as part of the process of end-of-life care-A decision was made regarding organ donation | -DBD: Australian audit combines suspected brain dead and those confirmed via testingDCD: UK places time restriction of anticipated to 4 hours-“End-of-Life Care Pool” data not publicly available | |
3 | “Eligible DBD donor.” Patients for whom death was confirmed following neurological tests and who had no absolute medical contraindications to solid organ donation | “Eligible DCD donor”Patients who had treatment withdrawn and death was anticipated within 4 hours, with no absolute medical contraindications to solid organ donation | “Potential donor”Any of the “End-of-Life Care pool” who were medically suitable/had no absolute medical contraindications to solid organ donation | -Differing terms-Neurological tests to confirm brain death for inclusion in category in both countries-Inclusion subject to differences in lists of absolute medical contraindications/medical suitability |
4 | “Approached DBD donors.” Eligible DBD families approached for consent/authorisation for donation | “Approached eligible DCD donors.” Eligible DCD donor families approached for consent/authorisation for donation | “Requests”Count of all cases where organ donation was discussed with the family and a final decision of consent or decline was made. Includes all requests, regardless of age or potential donor status, except cases where family was advised of lack of donor suitability | -Differing terms-Differing denominators with UK using eligible DBD/DCD donors only-UK also uses both terms “consent” and “authorisation” owing to different legislation in Scotland |
5 | “Consented DBD donors.” Families or nominated/appointed representatives of eligible DBD donors approached for formal organ donation discussion where consent/authorisation was ascertained | “Consented eligible DCD donors.” Families or nominated/appointed representatives of eligible DCD donors approached for formal organ donation discussion where consent/authorisation was ascertained | “Consents”Consent for organ donation is given by the family or next of kin. Cases where the family is advised of lack of donor suitability are not included | -Congruent in inclusion of actual family donation conversations in cases which had no absolute or prior identified medical contraindications |
6 | “Actual donors: DBD”: Consented, eligible DBD pathway patients who became actual DBD donors as defined by organ retrieval with the intention to transplant (unless returned to donor where considered unsuitable) | “Actual DCD donors”:Consented, eligible DCD pathway patients who became actual DCD donors as defined by organ retrieval with the intention to transplant (unless returned to donor where considered unsuitable) | “Actual donors”:A person for whom the organ retrieval procedure commenced in the operating room (with surgical incision) for the purpose of transplantation. This includes donors who may have been deemed medically unsuitable during surgery or after the removal of organs | -Actual donation defined at “knife to skin” of donor in Australia and “organ retrieval with the intention to transplant” in UK.-Select few in DBD pathway in UK who became DCD donors due to specific requests of family reported in audit. This does occur in Australia however is not publicly reported |
There were differences in the inclusion criteria of potential DBD- and DCD-pathway patients. For DBD in the UK, Tier 2 contains those suspected of brain death and meet criteria for formal neurological death testing whereas in Australia Tier 2 captures both suspected and confirmed brain dead patients. For DCD in the UK, a timeframe is applied to the potential DCD donor definition with inclusion if death was anticipated within 4 hours of withdrawal of life-sustaining treatment whereas Australia includes deaths which actually occurred within 6 h of withdrawal (or longer if DCD was planned but death did not occur within 6 h).
Tier 3 represents those in Tier 2 who are then deemed medically suitable with no absolute contraindications to donation. The UK refers to these patients as “Eligible DBD/DCD donors” as per the Critical Pathway (
Tier 4 refers to the interaction between donor families and healthcare staff including donation coordinators, nurses and hospital doctors. In the UK, donation coordinators are referred to generically as Specialist Nurse-Organ Donation (SNOD) and in Australia the term Donation Specialist Nurse encompasses a number of slightly varying roles. At this tier, differing semantics are used, however both “Approach” (UK) and “Request” (Australia) are used in the audit which refers to family approaches to offer donation. Where these definitions do differ is in their denominator, with only those deemed eligible included in the UK whereas in Australia it is all discussions held, including those which may have been raised by families or led by ICU staff where donation was initially considered feasible although ultimately the person was not suitable.
Tier 5 is the consent rate of those families approached or requested for donation. The combined DBD/DCD Australian figure means comparison of specific consent, between the two types of deceased organ donation, cannot be readily achieved such as in the UK.
Tier 6 counts where donation is considered to have taken place. In the UK, “actual donor” status is defined by organ retrieval with the intention to transplant whereas in Australia cases are included at the point of “knife to skin” of the donor, both irrespective of actual utilisation (implantation) of organs. A final difference in audit structure occurs here as the UK reports on the small proportion of those included in the DBD pathway who actually proceed down a DCD pathway due to specific requests from the family to be present when the heart stops beating. Such cases also occur in Australia in practice.
We next examined real data collected by both national audits (
Comparison of 2019 donation activity data in the UK and Australia across tiers. Population estimate used for per million population (pmp) calculations were 66.8 million in the UK and 25.37 in Australia for 2019.
Tier | Corresponding metric | UK (DBD + DCD) | Australia |
---|---|---|---|
1 | Deaths in chosen location (ICU) | 22688 (339 pmp) | 5990 (234 pmp) |
2 | Potential donors (UK) or EOL care pool (Aus) | Not included | Not included (not publicly available) |
3 | “Eligible” (UK)/“Potential” (Aus) | 5844 (87 pmp) | 1309 (51 pmp) |
4 | “Approached” (UK)/“Requested” (Aus) | 3351 (50 pmp) | 1224 (48 pmp) |
5 | Consents | 2276 (34 pmp) | 756 (30 pmp) |
Consent rate | 67.9% | 62% | |
6 | Actual donors | 1624 (24 pmp) | 548 (22 pmp) |
Direct comparison of UK and Australian deceased organ donation data was challenging due to differences in the metrics and definitions used by the national donation networks. A tiered structure allowed approximations at each step of the pathway and subsequently, certain comparisons could be cautiously made. Interpretation of comparisons requires detailed understanding of the way data is derived, collection methods, flow and the relationships between data points.
Difficulties in comparing national donation performance is not a new issue. Jansen et al. (2009) found significant heterogeneity in definitions used for “potential organ donor” and “refusal rate” across 11 European countries (
Many initiatives have attempted to establish and promulgate a set of standard definitions and metrics which measure donation performance. Most notably, the multi-national collaborative led by Dominguez et al. (2011) established the “critical pathway for deceased donation” which played an important role in providing a universal framework for the process of deceased organ donation (
Our group attempted to take up the mantle of this work. From our minutes, “The goal is the concept of potentially using our two databases and trying to bring them together so that we can actually have comparative metrics.” It was noted that the two audits, “…have probably evolved in different directions.” When comparing our audits, we first noted there were several significant general differences in their structure. The starting points varied due to differing inclusion criteria in estimating the “possible” donor pool. We also note that not all ICUs and EDs report all deaths where organ donation is possible in a consistent and standardised way. To identify the full depth of this pool would require an audit of all hospital deaths nationally (
We developed a tiered system based on the critical pathway for deceased donation to compare the definitions and metrics used by our audits. At almost every tier there were different uses of terminology and nuance in metrics. It was felt that much of the differences found were in the way data was reported rather than collected and that internal data could be produced which would more readily match the counterpart organisation’s data. Undertaking this work itself did help with interpreting each counterpart’s figures and some comparisons were felt to represent reasonable approximations.
There are several limitations with auditing donation performance in general. The audits attempt to simplify the messy real world of variably unfolding patient scenarios and different clinician practices and record-keeping. Difficulties arise in capturing scenarios outside of the expected ‘order of events’, for example where families are approached at earlier stages such as prior to brain death testing. Furthermore, the audits variably combine elements of retrospective data collection as well as data collection which is actively and purposefully collected during the donation process. For example, when recording potential DCD donors, the UK approach would be to include “A patient who had treatment withdrawn and death was anticipated within 4 hours”, this relying on the clear recording of “anticipation” of death during the donation process for later retrospective data collection. In other words, this element of the audit is conducted prospectively but collected retrospectively. In Australia, the observation that death occurred within 6 h of withdrawal of cardio-respiratory support (or beyond 6 h if donation had been planned) is the trigger for inclusion which necessitates the retrospective approach.
We also discussed the mutual development of “quality metrics”, including tracking characteristics of the donation conversation, from formalised pre-discussion planning sessions to presence of donation specialise staff. Notably, donation coordinator nursing staff involvement in donation conversations is implicated in increasing DBD and DCD consent rates (
Clearly, moving towards a shared reality, “international language” and uniform metrics is desirable.
Immediate actions and future directions.
• The most meaningful comparisons between the UK and Australian donation organisations begin at “Tier 4,” or the number “approached” or “requested” for donation. Further collaborations between our organisations should focus on downstream data comparisons including consent and conversion rates |
• Invite and encourage dialogue between other organ donation organisations interested in updating or evolving their audits by establishing a working group which would routinely meet at a recurring international conference such as the International Society for Organ Donation and Procurement (ISODP) Congress |
• The use of standardised definitions and metrics by databases which collect and publish data on organ donation and transplantation activity such as the Global Observatory on Donation and Transplantation (GODT) |
• Encourage the use of side-by-side descriptive information alongside data points in publications which aid the reader in understanding how each data point was derived |
We found that comparison of deceased organ donation data between two countries, which at first glance have similar culture and donation practice, was extremely challenging due to differences in our metrics and definitions. This would be compounded when comparing with even more countries and organ donation organisations. However, this work is essential if we are to search widely for solutions and learn from our partners when addressing the shortage of organs for transplantation. We do know that our goal is the same: the minimisation of unrealised potential donors. We therefore encourage, invite and hope to foster larger collaborative efforts from this international audience towards the goal of convergent evolution of definitions and metrics. This work will become increasingly relevant as practices in organ donation and transplantation evolve with society and time. It’s time to compare apples with apples when reporting donation performance.
The original contributions presented in the study are included in the article/Supplementary Material, further inquiries can be directed to the corresponding author.
Conceptualisation—LM, AM, and DG; Literature search—LM; Figure and table development—LM, CB, LG, KD, MG, SM, and MM; Writing—original draft—LM; Writing—review and editing, including verification of data—CB, LG, KD, MG, SM, MM, LB, HO, AM, and DG.
At the time of writing, LM was supported by a General Sir John Monash Foundation scholarship (2020) for a Master of Research (Immunobiology) at Newcastle University.
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.