Cardiac Arrest as an Extended Indication for Organ Donation

An Analysis of Potential in Germany Based on Retrospective Data From European Countries

Background: This study concerns the potential alleviation of the scarcity of donor organs in Germany by an extension of the indication for organ donation to cardiac arrest (donation after circulatory death, DCD).

Methods: Trends in the number of organ donations in nine European countries after the introduction of DCD were analyzed and projected onto the documented numbers of organ donations in Germany over the period 2011–2023 by means of regression analyses. The effect on liver and kidney transplantation in Germany was modeled for each scenario with the Eurotransplant simulators ELAS and ETKidney.

Results: Compared to the control scenario without DCD (829 liver transplantations), the largest increases in liver transplantation in 2023 were found with the scenarios for Spain (+384) and Switzerland (+290), followed by those for Belgium (+224), Italy (+155), the United Kingdom (+125), the Netherlands (+112), the Czech Republic (+87), and France (+69). Similarly, the largest increases in kidney transplantation compared to the control scenario without DCD (1361 kidney transplantations) were found in the scenarios for Spain (+1186), Switzerland (+850), the Netherlands (+699), the United Kingdom (+661), Italy (+551), Belgium (+455), the Czech Republic (+432), and France (+128). The Austrian scenario did not yield any increase in either liver or kidney transplantation (−10 and −44, respectively). In most of the scenarios, waiting lists, MELD scores, and the dialysis time at transplantation were reduced in parallel with the rise in the number of transplantations.

Conclusion: These scenarios indicate that the introduction of a DCD program could help make more organs available. Its effect would nonetheless depend on accompanying structural measures and societal factors. DCD would probably not solve the problem of organ scarcity if instituted as a single measure.

Cite this as: von Samson-Himmelstjerna FA, de Ferrante H, Niehus CB, Strelniece A, Kakavand N, Thomsen SY, Guenther R, Augsberg S, Vogelaar S, de Buijzer E, Tieken I, Schmitt R, Kolbrink B, Schulte K: Cardiac arrest as an extended indication for organ donation: An analysis of potential in Germany based on retrospective data from European countries. Dtsch Arztebl Int 2026; 123: 207–12. DOI: 10.3238/arztebl.m2026.0004

In Germany, many people with organ failure do not receive life-saving transplants due to a scarcity of donor organs (1). Under German law, donations from deceased donors are permitted only in cases of irreversible cessation of brain function (donation after brain death, DBD) (2), while in many European countries and other countries, including Japan, the United States and Australia, donations are also permitted in cases of cardiac arrest (donation after circulatory death, DCD) (3, 4). With this type of donation, death is determined based on the failure of the cardiovascular system. If circulatory function is not re-established during the subsequent no-touch period (an observation period typically ranging from 5 to 30 minutes), cessation of brain function is deemed to have occurred and organ retrieval is initiated (5). The Maastricht classification distinguishes between donations that are performed under uncontrolled conditions (e.g., following unsuccessful resuscitation; Maastricht II) and those performed under controlled conditions (e.g., following the planned discontinuation of intensive care; Maastricht III) (eSupplement Table S1) (6). The definitions of the general framework for donations after circulatory death vary between countries around the globe (eTable 1).

eTable 1

General framework for DCD donation in the reference countries

The aim of this study was to project trends in the number of controlled DCD donations in other European countries onto the documented numbers of organ donations in Germany and to model the potential effect of this type of donation on German waiting lists for kidney and liver transplantations.

Methods

Retrospective data from the initial phases of controlled DCD donations in other European countries were analyzed, projected onto the number of organ donations In Germany, and analyzed using simulation-based models (eFigure).

Figure

The historical development of organ donation in Europe

eFigure

Simulation of introduction of DCD donation in Germany as of 2011

Reference countries, dataset, controlled DCD donation

In order to ensure the greatest possible comparability with Germany, neighboring European countries with similar demographic and economic conditions were included in our potential analysis: Belgium, France, Italy, the Netherlands, Austria, Switzerland, Spain, the Czech Republic, and the United Kingdom. Some countries could not be included because DCD donation is not actively practiced there—in some cases even though it is legally permitted (Poland, Slovakia)—, or because the DCD donation programs have only recently been introduced (Finland, Norway, Sweden, Denmark). Data were obtained from the Global Observatory on Donation and Transplantation (4), the Eurotransplant (ET) database as well as from individual sources (eSupplement Methods S1). We based our analysis on the donation type of controlled DCD donation (Maastricht III) to ensure a conservative approach and because we assumed that this will be more readily accepted compared to uncontrolled donation. DCD was defined according to the Maastricht classification and the respective national regulations (eSupplement Table S1, eTable 1).

Modeling of the number of donations

We modeled potential numbers of organ donations in Germany by calculating, for each reference country, the country-specific increase in DCD donations following the introduction of the respective program, as well as the parallel trend in DBD donations, and projected these onto the historical baseline data for Germany. The method is described in detail in eSupplement Methods S2–6.

Regression analysis: DCD donation

We modeled the annual number of DCD donations for each country as a percentage of the annual total deceased donation rate (%) following the launch of a DCD donation program, expressed as a linear function of time. These scenario-specific regressions were projected onto the actual number of donations in Germany, so that in each scenario, a different number of additional German donors were added each year—with a scenario-specific rate of increase in the number of DCD donations. Given the fact that liver donations and kidney donations exhibit very different dynamics, we calculated this regression separately for each organ.

Regression analysis: DBD donation

At the same time, we looked at the trend in DBD donation numbers, given that the introduction of DCD donations could have a negative (e.g., due to a substitution effect) or positive (e.g., due to greater attention to donor identification) impact on the number of DBD donations (7, 8). We therefore modeled the simultaneously observed trend among DBD donors in each reference country, using a scenario-specific DBD-DCD interaction term. In this regression equation, we also accounted for the long-term trend in the number of DBD donations and the impact of the (post-)COVID years 2020–2024. The interaction term was calculated at the donor level, not at the organ level.

Combining the regressions

By combining the regressions, we were able to project the number of additional DCD donors that would have been expected in each scenario (1^st regression equation) and the expected number of DBD donors (2^nd regression equation) onto the historical German donation data, separately for liver and kidney.

Simulations

Based on the calculations described above, the number of organ donations in Germany after the hypothetical introduction of a DCD donation program was continuously adjusted from time point 0 onward for each specific scenario. We used the discrete-event simulators developed by Eurotransplant (ET) for their Liver Allocation System (ELAS) and kidney allocation (ETKidney) to assess the impact of these changed donation numbers on relevant endpoints (9, 10). The ET simulators are based on the currently valid Eurotransplant allocation rules and incorporate stochastic elements, such as the acceptance or rejection of organ offers or waiting list mortality. These rules were developed and validated using historical data of all donors in the ET database, waiting list candidates and transplant recipients. With this approach, it was possible to realistically simulate changes in allocation and waiting list trends in response to changes in donation numbers and to assess the impact on various outcomes. For both liver and kidney transplants, ten scenarios were calculated for German patients: One scenario without the introduction of DCD donation (control scenario) and nine additional scenarios based on donation numbers for Germany derived from the above-mentioned reference countries.

Endpoints

The endpoints evaluated were the number of donors, the number of transplantations, the MELD score at the time of transplantation (liver), and the pretransplant dialysis duration (kidney). The number of donors was estimated based on the regression equations. The waiting list size resulted directly from the simulation process: The actual German waiting list, starting 1 January 2011, was continued and patients transplanted, deceased or otherwise excluded during the course of the simulation were removed from the list. For each year, we then looked at how many patients were on the active waiting list. The MELD score at transplantation and the pretransplant dialysis duration can be used to determine the prognosis with which the transplantation is performed (11, 12). These two parameters resulted from the transplantations performed during the simulation run. Due to the stochastic elements in the simulation, the results varied across the simulation runs. For each endpoint, the median and the estimated 95% interquartile range from 10 runs are reported (eSupplement Methods S6).

Observation period and missing data

An observation window of up to 13 years following the national introduction of controlled DCD donation was analyzed for each reference country in order to calculate specific regressions (e.g., the Netherlands 1995–2007, France 2015–2024; Figure). If empiric data were only available for a period of less than 13 years, the time series was supplemented by linear extrapolation (eSupplement Methods S2.2 and S5).

The hypothetical change in the numbers of donations was subsequently projected onto Germany and applied in a fixed 13-year simulation period from 1 January 2011 to 31 December 2023. We chose this starting point because the ET simulators were only able to provide consistent input data starting that year. The selected endpoint marks the last point in time for which fully validated data was available.

Results

Number of donations and transplantations

In the scenarios with DCD donation, the regression analyses found higher total donation rates for both liver (Table 1) and kidney donations (Table 2) compared to the scenario without DCD donation—with the exception of the Austrian scenario. On this basis, higher numbers of transplantations, which increased continuously, followed in eight of the nine simulated scenarios (eTables 2 and 3). We found that the significant variance in the models was dependent on the simulation year and the corresponding baseline values. In the scenario without DCD donation, the numbers of transplantations were almost identical to the actual historical data, indicating that the simulation models were well calibrated (Tables 1 and 2). While the number of liver transplantations in 2023 would have remained virtually unchanged in the Austrian scenario (−10) compared to the scenario without DCD donations (829 liver transplantations), the Belgian (+224), Swiss (+290) and Spanish (+384) scenarios, in particular, would have resulted in significantly higher numbers of liver transplantations. For kidney transplantations (1361 in the scenario without DCD donation), the Austrian scenario (−44) would even have shown minimal decreases, while the British (+661), Dutch (+699), Swiss (+850), and Spanish (+1,186) scenarios would have seen significant gains. Due to the overall decline in organ donation numbers in Germany, the 2023 number of transplantations in most scenarios would still have remained below the preceding 2010 level in Germany (eSupplement Tables S2 and S3).

Table 1

Simulated state of deceased donor liver donation in Germany in 2023; 13 years after hypothetical introduction of DCD donation

Table 2

Simulation of the kidney transplantation situation in Germany 13 years after hypothetical introduction of controlled DCD donation

eTable 2

Simulated development of deceased donor liver transplantations in Germany after the introduction of DCD donation

eTable 3

Simulated development of deceased donor kidney transplantations in Germany after the introduction of DCD donation

Waiting list trends

The number of patients on the waiting list in Germany has been decreasing since 2010 due to a decline in the number of newly registered patients (13). In addition, the size of the waiting list has been reduced by the number of transplantations and the number of deaths among patients on the waiting list. The simulations showed that the number of patients on the waiting lists in most scenarios with DCD donations would have fallen more sharply compared to the scenario without DCD donation (Tables 1 and 2, eSupplement Tables S4 and S5). In the Italian scenario, for example, the number of patients on the liver transplant waiting list would have decreased from 843 to 623 and on the kidney transplant waiting list from 6273 to 4198, which, compared to the other scenarios, represented a moderate effect.

MELD score at liver transplantation

With the help of the ELAS simulator, we could also study the effect of the additional donations on the MELD score at liver transplantation. In line with the waiting list trend, the MELD score also decreased in the scenario without introduction of the DCD donation from 31 to 26 between 2011 and 2023 (eSupplement Table S6). While the median MELD score would have remained largely unchanged in the Austrian (27), French (25), British (25), and Czech (25) scenarios, it would have fallen significantly in the Swiss (22) and Spanish (22) scenarios (Table 1).

Dialysis duration at kidney transplantation

With the help of the ETKidney simulator, we were also able to compare trends in median pretransplant dialysis duration between the various scenarios; since 2011, pretransplant dialysis durations had increased continuously in the scenario without DCD donation and would have reached 7.3 years by 2023 (Table 2, eSupplement Table S7). No significant changes would have occurred in the Austrian (7.5 years) and French (7.0 years) scenarios. However, shorter waiting times would have resulted in the Dutch (4.7 years), Belgian (5.8 years), Czech (5.8 years), Italian (5.5 years), British (5.2 years), Swiss (4.9 years), and Spanish (3.6 years) scenarios.

Discussion

The findings of our potential analysis were heterogeneous. In the Austrian and French scenarios, the change in the overall situation would hardly be noticeable. In the other scenarios, on the other hand, in particular those for Switzerland and Spain, the introduction of DCD donation would have resulted in improved or even significantly improved access to transplants.

With regard to the organ donation activity in 2024, Germany ranked 25^th out of 42 countries in Europe and 19^th out of 27 within the European Union; in contrast to most European countries, Germany has not been able to significantly improve its organ donation numbers over the last 10 years (eSupplement Tables S8, S9). While the number of living donations has recovered from an intercurrent period of decline to almost the 2015 level, the number of donations from deceased donors has remained stagnant at about 11 donors per million population since 2013 (Figure). It would therefore be reasonable to explore whether expanding the indication for donation to include the DCD donation could change this situation.

First, however, it should be noted that in Germany currently donations from deceased donors are permitted only after confirmation of brain death (DBD). For this, DBD must be confirmed by two independent specialists through repeated clinical examinations and ancillary tests. In the case of DCD donation, it is assumed that, due to the cessation of perfusion, no brain activity is present at the time of organ retrieval; however, this lack of activity is not necessarily irreversible, at least not if the no-touch period is as short as five minutes. In the case of DCD donation, the irreversibility results primarily from the decision not to resuscitate (15). Thus, DCD donation is currently not legally permitted in Germany, because DBD is not confirmed. Accordingly, the guidelines of the German Medical Association do not provide for DCD donation.

Given the rather reserved attitude toward organ donation prevailing in Germany, it seems unlikely that very liberal DCD donation protocols, e.g. with brief no-touch periods, would be put into practice. While liberal donation protocols allow for organ donation from a larger number of deceased persons, they may raise greater ethical concerns. Likewise, uncontrolled DCD donation, e.g. from persons who are dead by the time they arrive at the hospital (Maastricht I) or become donors immediately after unsuccessful resuscitation (Maastricht II), does not seem realistic for Germany. Nevertheless, our analysis indicates that even with strict protocols in place for controlled DCD donation, which require a very long no-touch period (20 minutes in Italy), an improvement in organ donation rates may still be achieved. The fact that despite the long no-touch periods the Italian transplant survival rates are comparable to those of other countries suggests that this approach could be a potential option for Germany, provided that machine perfusion is used to compensate for prolonged ischemia times (16). It would also be conceivable that prior to organ retrieval the absence of brainstem reflexes is once again confirmed by clinical examination, as required by the Austrian (17) and Swiss (18) protocols. Another measure to further increase social acceptance could be to make an explicit consent to DCD donation in the organ donor card or organ donor registry a requirement.

In Austria, for example, the lack of systematic structural improvements meant that overall transplant numbers did not increase, even after the nationwide introduction of a gradually expanding DCD donor program; this shows that it is not enough to simply create the legal framework for DCD donation. After all, high levels of acceptance in society, standardized organ retrieval protocols and reliable donor identification at organ retrieval hospitals are critical success factors for both DBD and DCD donations (19). Widespread availability of machine perfusion of the organs retrieved from DCD donors is also essential (20). Well-coordinated approaches can increase donation numbers, as the example of Switzerland shows: Since 2013, a systematic optimization approach has been pursued in Switzerland, with improvements achieved in the areas of training for medical staff, process and quality management, hospital structures and resources, as well as public awareness campaigns and public relations (21). Alongside this, the DCD donation program was established at the hospitals starting in 2011 and added to the “More Organs for Transplantation” action plan (22).

From this, we come to the conclusion that sustainable improvements in the number of organ donations in Germany can only be achieved through a combination of legislative changes and comprehensive structural reforms (23).

Limitations

While our potential analysis does outline the scope of what could be achieved by introducing DCD donation in Germany, it does not allow us to predict the prognosis directly, as this would depend heavily on the actual implementation. Given its retrospective nature, however, our analysis cannot provide proof of a causal link between the introduction of DCD donation and an increase in overall donation numbers.

Data from various time periods were included in the analyses, complicating the comparison between the scenarios: While in some countries (e.g., Switzerland and Italy) DCD donation has been introduced quite recently, it was established in other reference countries (e.g. the Netherlands and the United Kingdom) already more than 20 years ago. Furthermore, the design of our model did not allow to explicitly account for any societal developments that occurred concurrent with the respective introduction of DCD donation, e.g., the Swiss action plan (21, 22) mentioned above. Instead, the numbers of organ donations were simply projected onto the German scenario, thus leaving the underlying causal factors implicit. In certain scenarios where DCD donation has only recently been introduced, no full three-year dataset was available, resulting in the need for extrapolation. We also had to make adjustments for the COVID-19 pandemic period in these scenarios. However, we deliberately took a conservative approach, notably by focusing on controlled DCD donations and factoring in potential effects on the number of DBD donations.

The study design had not been registered in a relevant database prior to the conduct of the analyses.

Conclusion

The extent to which DCD donation can contribute to improving the organ donation situation in Germany depends significantly on the way it is put into practice and on supporting systemic measures. First, a legal framework would need to be created. The findings of our study suggest that the introduction of DCD donation could help alleviate the scarcity of donor organs, but would likely not be sufficient on its own to resolve it.

Ethics
This study did not require ethical approval. Eurotransplant is subject to the Dutch Medical Research Involving Human Subjects Act (WMO), under which no ethics committee approval is required for analyses using pseudonymized registry data. For the analyses in Germany, only aggregated, non-personal data was available; pursuant to the European Union‘s General Data Protection Regulation (GDPR) and Section 27 of the German Federal Data Protection Act (BDSG), no ethics review was therefore required.

Conflict of interest
BK received research funding from Sanofi.

FAvSH received lecture fees as well as reimbursement of congress fees and travel expenses from Chiesi GmbH, from Lilly Deutschland GmbH and from Astra Zeneca GmbH.

SYT received lecture fees from Astra Zeneca GmbH and Chiesi GmbH as well as reimbursement of travel expenses from Lilly Deutschland GmbH.

The remaining authors declare no conflict of interest.

Manuscript received on 14 April 2025; revised version accepted on 15 January 2026

Translated from the original German by Ralf Thoene, M.D.

Corresponding author
Dr. med. Friedrich A. von Samson-Himmelstjerna

References

1. Schulte K, Borzikowsky C, Rahmel A, et al.: Decline in organ donation in Germany—a nationwide secondary analysis of all inpatient cases. Dtsch Arztebl Int 2018; 115: 463–8

2. Guenther R: Organmangel in Deutschland. Potenziale der kontrollierten Organspende nach Kreislauftod (cDCDD). München: GRIN Verlag 2024; 1–28.

3. Lomero M, Gardiner D, Coll E, et al.: Donation after circulatory death today: An updated overview of the European landscape. Transplant Int 2020; 33: 76–88

4. WHO-ONT: Global Observatory on Donation and Transplantation www.transplant-observatory.org/ (last accessed on 22 November 2024).

5. Summers DM, Watson CJ, Pettigrew GJ, et al.: Kidney donation after circulatory death (DCD): State of the art. Kidney Int 2015; 88: 241–9

6. Thuong M, Ruiz A, Evrard P, et al.: New classification of donation after circulatory death donors definitions and terminology. Transplant Int 2016; 29: 749–59

7. Summers DM, Counter C, Johnson RJ, Murphy PG, Neuberger JM, Bradley JA: Is the increase in DCD organ donors in the United Kingdom contributing to a decline in DBD donors? Transplantation 2010; 90: 1506–10

8. Broderick AR, Manara A, Bramhall S, Cartmill M, Gardiner D, Neuberger J: A donation after circulatory death program has the potential to increase the number of donors after brain death. Crit Care Med 2016; 44: 352–9

9. de Ferrante HC, Goya RL, Smeulders BML, Spieksma FCR, Tieken I: The ETKidney simulator: A discrete event simulator to assess the impact of alternative kidney allocation rules in Eurotransplant. arXiv preprint 2025; arXiv:2502.15001.

10. de Ferrante HC, de Rosner-Van Rosmalen M, Smeulders BML, Spieksma FCR, Vogelaar S: A discrete event simulator for policy evaluation in deceased-donor liver allocation in Eurotransplant. ORDAL 2025; 45: 200476

11. Narayanan Menon KV, Nyberg SL, Harmsen WS, et al.: MELD and other factors associated with survival after liver transplantation. Am J Transplant 2004; 4: 819–25

12. Lim JH, Jeon Y, Kim DG, et al.: Effect of pretransplant dialysis vintage on clinical outcomes in deceased donor kidney transplant. Sci Rep 2022; 12: 17614

13. Eurotransplant: Annual Report 2023 www.eurotransplant.org/wp-content/uploads/2024/06/ETP_AR2023_LowRes.pdf (last accessed on 30 July 2024).

14. DSO: Jahresbericht 2024 www.dso.de/SiteCollectionDocuments/DSO-Jahresbericht%202024.pdf (last accessed on 31 August 2025).

15. Dalle Ave AL, Bernat JL: Using the brain criterion in organ donation after the circulatory determination of death. J Crit Care 2016; 33: 114–8

16. Favi E, Vespasiano F, Cardillo M, Ferraresso M: DCD kidney transplantation in Italy: Past, present, and future. Transplantation Rep 2022; 7: 100121

17. FASIM: Empfehlungen zur Durchführung der Todesfeststellung bei einer geplanten Organentnahme nach Hirntod durch Kreislaufstillstand https://transplant.goeg.at/sites/transplant.goeg.at/files/inline-files/Empfehlungen%20zur%20Durchf%C3%BChrung%20der%20Todesfeststellung%20bei%20einer%20geplanten%20Organentnahme%20nach%20Hirntod%20durch%20Kreislaufstillstand.pdf(last accessed on 31 August 2025).

18. SAMW: Feststellung des Todes im Hinblick auf Organtransplantationen und Vorbereitung der Organentnahme. www.samw.ch/dam/jcr:4a69851d-bd05-49b3-a209-3ce28d66372e/richtlinien_samw_feststellung_tod_organentnahme.pdf (last accessed on 31 August 2025).

19. Rand A, Koch T, Ragaller M: [Organ donation-Not only a responsibility of intensive care medicine]. Anaesthesist 2022; 71: 311–7

20. Brat A, de Vries KM, van Heurn EWE, et al.: Hypothermic machine perfusion as a national standard preservation method for deceased donor kidneys. Transplantation 2022; 106: 1043–50

21. BAG: Aktionsplan „Mehr Organe für Transplantationen“ – Schlussbericht 2013–2018 www.bag.admin.ch/dam/de/sd-web/rp1oUGYgZARY/schlussbericht-aktionsplan-2013–2018.pdf (last accessed on 4 February 2025).

22. BAG: Aktionsplan „Mehr Organe für Transplantationen“ – Schlussbericht Verlängerung 2019–2021 www.bag.admin.ch/dam/de/sd-web/vKkgvtmsBrUV/schlussbericht-aktionsplan-2019–2021.pdf (last accessed on 4 February 2025).

23. Braun F, Abel W, Middel CD: Organspende in Deutschland: „Wind of Change“? Zentralbl Chir 2021; 146: 407–12