Revival der Hirntod-Debatte: Funktionelle Bildgebung für die Hirntod-Diagnostik

[Brain death criterion and organ donation: current neuroscientific perspective]

In der akademischen und öffentlichen Debatte wird der irreversible Hirnfunktionsausfall als Kriterium des Todes (Hirntodkriterium) immer wieder hinterfragt. Im vorliegenden Artikel werden 6 prototypische Thesen gegen das Hirntodkriterium diskutiert: 1) Nichtsuperiorität des Gehirns gegenüber anderen Organen, 2) Unsicherheit der Hirntoddiagnostik, 3) erhaltene Schmerzempfindung Hirntoter, 4) (spontane) sexuelle Reifung und erhaltene Reproduktionsfunktion Hirntoter, 5) Symmetrie von Hirntod und Embryonalphase, 6) Gleichsetzung des intensivmedizinisch erhaltenen Restorganismus Hirntoter mit dem lebenden Menschen.

Keine dieser Thesen hält einer kritischen Analyse stand. In Deutschland wird das Ganzhirntodkriterium angewendet. Der Hirntod geht mit dem völligen Ausfall jeglicher Empfindung, Bewusstheit, Mimik, Augen‑, Zungen- und Schlundmotorik, Willkürmotorik und Sexualfunktion einher (funktionelle „Enthauptung“). Medizinisch-technisch können andere Organe bzw. ihre Primitivsteuerung ersetzt werden, nicht aber das Gehirn. Das Gehirn, nicht der Körper, ist bestimmend für das menschliche Individuum. Die Gleichsetzung des künstlich erhaltenen Restorganismus, naturphilosophisch als lebendiges System interpretierbar, mit dem Organismus desselben lebenden Menschen wird durch die beliebige Reduzierbarkeit der Anzahl beteiligter Organe ad absurdum geführt. Der irreversible Hirnfunktionsausfall führt unausweichlich zum Herzstillstand, unbehandelt innerhalb von Minuten, unter Intensivtherapie i. d. R. innerhalb von Tagen. Auch beim Embryo/Fötus führt die Fehlanlage des gesamten Gehirns zum (vorgeburtlichen) Tod. Die in Deutschland gesetzliche Richtlinie zur Hirntodfeststellung hat eine im internationalen Vergleich hohe Diagnosesicherheit, es sind damit keine bestätigten Fehldiagnosen aufgetreten.

When are you dead enough to be a donor? Can any feasible protocol for the determination of death on circulatory criteria respect the dead donor rule?

The basic question concerning the compatibility of donation after circulatory death (DCD) protocols with the dead donor rule is whether such protocols can guarantee that the loss of relevant biological functions is truly irreversible. Which functions are the relevant ones? I argue that the answer to this question can be derived neither from a proper understanding of the meaning of the term "death" nor from a proper understanding of the nature of death as a biological phenomenon. The concept of death can be made fully determinate only by stipulation. I propose to focus on the irreversible loss of the capacity for consciousness and the capacity for spontaneous breathing. Having accepted that proposal, the meaning of "irreversibility" need not be twisted in order to claim that DCD protocols can guarantee that the loss of these functions is irreversible. And this guarantee does not mean that reversing that loss is either conceptually impossible or known to be impossible with absolute certainty.

A cross-cultural analysis of posthumous reproduction: The significance of the gender and margins-of-life perspectives

The scholarly discussion of posthumous reproduction (PHR) focuses on informed consent and the welfare of the future child, for the most part overlooking cultural differences between societies. Based on a cross-cultural comparison of legal and regulatory documents, analysis of pivotal cases and study of scholarly and media discussions in Israel and Germany, this paper analyses the relevant ethical and policy issues, and questions how cultural differences shape the practice of PHR. The findings challenge the common classifications of PHR by highlighting the gender perspective and adding brain-dead pregnant women to the debate. Based on this study's findings, four neglected cultural factors affecting social attitudes towards PHR are identified: (i) the relationship between the pregnant woman and her future child; (ii) what constitutes the beginning of life; (iii) what constitutes dying; and (iv) the social agent(s) seeking to have the future child. The paper argues that PHR can be better understood by adding the gender and margins-of-life perspectives, and that future ethical and practical discussions of this issue could benefit from the criteria emerging from this cross-cultural analysis.

[Ancillary procedures in the diagnostics of brain death. Utilization, results and consequences in northeastern Germany]

BACKGROUND

According to the German Medical Council guidelines, the proof of irreversible brain death can be carried out using clinical investigations alone or can necessitate the use of ancillary tests (ATs), depending on the patient age and type of brain injury.

METHODS

Retrospective evaluation of the diagnostics of irreversible brain death, which were carried out using ATs according to the third edition of the guidelines between January 2001 and December 2010 in Berlin, Brandenburg and Mecklenburg-Western Pomerania and were registered at the German National Foundation for Organ Transplantation.

RESULTS

In 1401 patients (aged 0-94 years) a total of 1636 ATs were carried out. The most frequently used additional procedure for the first AT was an electroencephalogram (EEG) in 71.7 %. Confirmatory results regarding irreversibility were reported for 93.6 % of the initial ATs. Negative results of ATs were less common with primary supratentorial brain lesions (2.9 %) compared to infratentorial lesions (13.7 %), secondary hypoxic brain damage (8.1 %) and children younger than 2 years old (18.5 %). Regardless of the AT results, a return of clinical brain function was never documented. The timing, type and repetition of ATs were variable. In most cases the diagnostic process was clearly accelerated by the use of ATs but was significantly delayed in 10.1 % compared to a purely clinical proof of irreversible brain death.

CONCLUSION

ATs by themselves do not provide evidence of the cessation of all brain functions. Instead, they are used to prove the irreversibility of the clinically defined syndrome. For patients over 2 years old and in the absence of primary brainstem lesions, clinical re-assessment and ATs are considered to be equally accurate in demonstrating irreversibility. A standardization of diagnostic procedures between hospitals would be desirable.

Decision solution, data manipulation and trust: The (un-)willingness to donate organs in Germany in critical times

In 2011 and 2012 a change of rules and a data-manipulation scandal focused German public attention on organ donation. This increased citizens' background knowledge as well as their willingness to respond to surveys. The present study is an effort to seize this research opportunity and to create evidence on which policy recommendations can be conceivably based. It uses data from two major representative surveys from 2011 to 2012 to address four central questions: Which characteristics, experiences and attitudes correlate with the written or unwritten willingness of individuals to donate (WTD) their own organs post-mortem? How has the WTD changed over time? To what extent does the WTD depend on normative trust? Which factors correlate with trust? The data is analyzed through summary statistics and regression models. Several hypotheses regarding factors connected with the WTD are confirmed in the survey results. Altruistic motives, relevant knowledge and trust are decisive. The special role of trust is corroborated by the data. As current German politics prevents the introduction of post-mortem donation incentives, potential policy making proposals are restricted to institutional changes to regain trust including the implementation of an organ donor registry and the advancement of counselling talks with general practitioners.