A brain-based definition of death and criteria for its determination after arrest of circulation or neurologic function in Canada: a 2023 clinical practice guideline.

This 2023 Clinical Practice Guideline provides the biomedical definition of death based on permanent cessation of brain function that applies to all persons, as well as recommendations for death determination by circulatory criteria for potential organ donors and death determination by neurologic criteria for all mechanically ventilated patients regardless of organ donation potential. This Guideline is endorsed by the Canadian Critical Care Society, the Canadian Medical Association, the Canadian Association of Critical Care Nurses, Canadian Anesthesiologists' Society, the Canadian Neurological Sciences Federation (representing the Canadian Neurological Society, Canadian Neurosurgical Society, Canadian Society of Clinical Neurophysiologists, Canadian Association of Child Neurology, Canadian Society of Neuroradiology, and Canadian Stroke Consortium), Canadian Blood Services, the Canadian Donation and Transplantation Research Program, the Canadian Association of Emergency Physicians, the Nurse Practitioners Association of Canada, and the Canadian Cardiovascular Critical Care Society.

RéSUMé: Ces Lignes directrices de pratique clinique 2023 Lignes directrices de pratique clinique dicale du décès basée sur l'arrêt permanent de la fonction cérébrale qui s'applique à toute personne, ainsi que des recommandations pour la détermination du décès par des critères circulatoires pour des donneurs d'organes potentiels et des recommandations pour la détermination du décès par des critères neurologiques pour tous les patients sous ventilation mécanique, indépendamment de leur potentiel de donneur d'organes. Les présentes Lignes directrices sont approuvées par la Société canadienne de soins intensifs, l'Association médicale canadienne, l'Association canadienne des infirmiers/infirmières en soins intensifs, la Société canadienne des anesthésiologistes, la Fédération des sciences neurologiques du Canada (représentant la Société canadienne de neurologie, la Société canadienne de neurochirurgie, la Société canadienne de neurophysiologie clinique, l'Association canadienne de neurologie pédiatrique, la Société canadienne de neuroradiologie et le Consortium neurovasculaire canadien), la Société canadienne du sang, le Programme de recherche en don et transplantation du Canada, l'Association canadienne des médecins d'urgence, l'Association des infirmières et infirmiers praticiens du Canada, et la Société canadienne de soins intensifs cardiovasculaires (CANCARE) et la Société canadienne de pédiatrie.

Rationale for revisions to the definition of death and criteria for its determination in Canada.

Clarity regarding the biomedical definition of death and the criteria for its determination is critical to inform practices in clinical care, medical research, law, and organ donation. While best practices for death determination by neurologic criteria and circulatory criteria were previously outlined in Canadian medical guidelines, several issues have arisen to force their reappraisal. Ongoing scientific discovery, corresponding changes in medical practice, and legal and ethical challenges compel a comprehensive update. Accordingly, the A Brain-Based Definition of Death and Criteria for its Determination After Arrest of Neurologic or Circulatory Function in Canada project was undertaken to a develop a unified brain-based definition of death, and to establish criteria for its determination after devastating brain injury and/or circulatory arrest. Specifically, the project had three objectives: (1) to clarify that death is defined in terms of brain functions; (2) to clarify how a brain-based definition of death is articulated; and (3) to clarify the criteria for determining if the brain-based definition is met. The updated death determination guideline therefore defines death as the permanent cessation of brain function and describes corresponding circulatory and neurologic criteria to ascertain the permanent cessation of brain function. This article explores the challenges that prompted revisions to the biomedical definition of death and the criteria for its determination and outlines the rationales underpinning the project's three objectives. By clarifying that all death is defined in terms of brain function, the project seeks to align guidelines with contemporary medicolegal understandings of the biological basis of death.

RéSUMé: Il est essentiel que la définition biomédicale du décès et les critères de sa détermination soient précis afin d'éclairer les pratiques en matière de soins cliniques, de recherche médicale, de droit et de don d'organes. Alors que les meilleures pratiques pour la détermination du décès par des critères neurologiques et circulatoires ont déjà été décrites dans les lignes directrices médicales canadiennes, plusieurs problèmes ont été soulevés, lesquels ont motivé leur réévaluation. Les découvertes scientifiques en cours, les changements correspondants dans la pratique médicale et les défis juridiques et éthiques imposent une mise à jour complète. Par conséquent, le projet d'Élaboration d'une définition uniformisée de la mort cérébrale et de critères fondés sur des données probantes pour sa détermination au Canada a été entrepris dans le but d'élaborer une définition uniformisée de la mort cérébrale et d'établir des critères pour sa détermination après une lésion cérébrale dévastatrice et/ou un arrêt circulatoire. Plus précisément, le projet avait trois objectifs : (1) clarifier que le décès est défini en termes de fonctions cérébrales; (2) clarifier la façon dont une définition cérébrale du décès est articulée; et (3) clarifier les critères permettant de déterminer si la définition de mort cérébrale est respectée. Les lignes directrices mises à jour sur la détermination du décès définissent donc le décès comme l'arrêt permanent de la fonction cérébrale et décrivent les critères circulatoires et neurologiques correspondants pour établir l'arrêt permanent de la fonction cérébrale. Cet article explore les défis qui ont motivé la révision de la définition biomédicale du décès et des critères de sa détermination et décrit les raisons d'être qui sous-tendent les trois objectifs du projet. En précisant que tout décès est défini en termes de fonction cérébrale, le projet cherche à aligner les lignes directrices sur les compréhensions médicolégales contemporaines des fondements biologiques de la mort.

What does "brainstem death" mean? A review of international protocols.

PURPOSE: The term "brainstem death" is ambiguous; it can be used to refer either exclusively to loss of function of the brainstem or loss of function of the whole brain. We aimed to establish the term's intended meaning in national protocols for the determination of brain death/death by neurologic criteria (BD/DNC) from around the world. METHODS: Of 78 unique international protocols on determination of BD/DNC, we identified eight that referred exclusively to loss of function of the brainstem in the definition of death. Each protocol was reviewed to ascertain whether it 1) required assessment for loss of function of the whole brain, 2) required assessment only for loss of function of the brainstem, or 3) was ambiguous about whether loss of function of the higher brain was required to declare DNC. RESULTS: Of the eight protocols, two (25%) required assessment for loss of function of the whole brain, three (37.5%) only required assessment for loss of function of the brainstem, and three (37.5%) were ambiguous about whether loss of function of the higher brain was required to declare death. The overall agreement between raters was 94% (κ = 0.91). CONCLUSIONS: There is international variability in the intended meaning of the terms "brainstem death" and "whole brain death" resulting in ambiguity and potentially inaccurate or inconsistent diagnosis. Regardless of the nomenclature, we advocate for national protocols to be clear regarding any requirement for ancillary testing in cases of primary infratentorial brain injury who may fulfill clinical criteria for BD/DNC.

RéSUMé: OBJECTIF: Le terme « mort du tronc cérébral ¼ est ambigu; il peut être utilisé pour désigner soit la perte de fonction du tronc cérébral uniquement, soit la perte de fonction du cerveau entier. Nous avons cherché à établir la signification voulue du terme dans les protocoles nationaux utilisés pour la détermination de la mort cérébrale/du décès selon des critères neurologiques (MC/DCN) du monde entier. MéTHODE: Sur 78 protocoles internationaux uniques sur la détermination de la MC/DCN, nous en avons identifié huit qui faisaient exclusivement référence à la perte de fonction du tronc cérébral dans la définition de la mort. Chaque protocole a été examiné pour déterminer s'il 1) exigeait une évaluation de la perte de fonction du cerveau entier, 2) exigeait une évaluation uniquement pour la perte de fonction du tronc cérébral, ou 3) était ambigu quant à savoir si la perte de fonction du cerveau supérieur était requise pour déclarer un DCN. RéSULTATS: Sur les huit protocoles, deux (25 %) exigeaient une évaluation de la perte de fonction de l'ensemble du cerveau, trois (37,5 %) ne nécessitaient qu'une évaluation de la perte de fonction du tronc cérébral, et trois (37,5 %) étaient ambigus quant à savoir si la perte de fonction du cerveau supérieur était nécessaire pour déclarer le décès. L'accord global entre les évaluateurs était de 94 %, (κ = 0,91). CONCLUSION: Il existe une variabilité internationale quant au sens voulu des termes « mort du tronc cérébral ¼ et « mort cérébrale totale ¼ qui entraîne une ambiguïté et un diagnostic potentiellement inexact ou incohérent. Quelle que soit la nomenclature, nous préconisons que les protocoles nationaux soient clairs en ce qui concerne toute exigence d'examens auxiliaires dans les cas de lésion cérébrale infratentorielle primaire qui pourraient répondre aux critères cliniques de MC/DCN.

Barriers to the Use of Neurologic Criteria to Declare Death in Africa.

There are varying medical, legal, social, religious and philosophical perspectives about the distinction between life and death. Death can be declared using cardiopulmonary or neurologic criteria throughout much of the world. After solicitation of brain death/death by neurologic criteria (BD/DNC) protocols from contacts around the world, we found that the percentage of countries with BD/DNC protocols is much lower in Africa than other developing regions. We performed an informal review of the literature to identify barriers to declaration of BD/DNC in Africa. We found that there are numerous medical, legal, social and religious barriers to the creation of BD/DNC protocols in Africa including 1) limited number of healthcare facilities, critical care resources and clinicians with relevant expertise; 2) absence of a political and legal framework codifying death; and 3) cultural and religious perspectives that present ideological conflict with the idea of BD/DNC, in particular, and between traditional and Western medicine, in general. Because there are a number of unique barriers to the creation of BD/DNC protocols in Africa, it remains to be seen how the World Brain Death Project, which is intended to create minimum standards for BD/DNC around the world, will impact BD/DNC determination in Africa.

Heart donation and transplantation after circulatory determination of death: expert guidance from a Canadian consensus building process.

Controlled donation after circulatory determination of death (DCD), where death is determined after cardiac arrest, has been responsible for the largest quantitative increase in Canadian organ donation and transplants, but not for heart transplants. Innovative international advances in DCD heart transplantation include direct procurement and perfusion (DPP) and normothermic regional perfusion (NRP). After death is determined, DPP involves removal and reanimation of the arrested heart on an ex situ organ perfusion system. Normothermic regional perfusion involves surgically interrupting (ligating the aortic arch vessels) brain blood flow after death determination, followed by restarting the heart and circulation in situ using extracorporeal membrane oxygenation. The objectives of this Canadian consensus building process by a multidisciplinary group of Canadian stakeholders were to review current evidence and international DCD heart experience, comparatively evaluate international protocols with existing Canadian medical, legal, and ethical practices, and to discuss implementation barriers. Review of current evidence and international experience of DCD heart donation (DPP and NRP) determined that DCD heart donation could be used to provide opportunities for more heart transplants in Canada, saving additional lives. Although candid discussion identified a number of potential barriers and challenges for implementing DCD heart donation in Canada, it was determined that DPP implementation is feasible (pending regulatory approval for the use of an ex situ perfusion device in humans) and in alignment with current medical guidelines for DCD. Nevertheless, further work is required to evaluate the consistency of NRP with current Canadian death determination policy and to ensure the absence of brain perfusion during this process.

RéSUMé: Le don contrôlé après un décès circulatoire (DDC), cas dans lequel le décès est déterminé après un arrêt cardiaque, est à l'origine de la plus forte augmentation quantitative des dons et des transplantations d'organes au Canada, sauf pour les transplantations cardiaques. Parmi les progrès internationaux novateurs dans la transplantation cardiaque après DDC, citons l'obtention directe et perfusion (ODP) et la circulation régionale normothermique (CRN). Une fois le décès déterminé, l'ODP consiste à retirer et réanimer le cœur arrêté sur un système de perfusion ex situ. La circulation régionale normothermique consiste à interrompre de manière chirurgicale (en ligaturant les vaisseaux de l'arc aortique) le flux sanguin au cerveau après la détermination du décès, puis à redémarrer le cœur et la circulation in situ utilisant l'oxygénation par membrane extracorporelle (ECMO). Les objectifs de ce processus canadien d'établissement de consensus par un groupe multidisciplinaire d'intervenants canadiens étaient d'examiner les données probantes et les expériences internationales actuelles en matière de DDC, d'évaluer comparativement les protocoles internationaux par rapport aux pratiques médicales, juridiques et éthiques canadiennes existantes, et de discuter des obstacles à la mise en œuvre de tels protocoles. L'examen des données probantes et des expériences internationales actuelles en matière de don de cœur après DDC (ODP et CRN) a permis de déterminer que le don de cœur après DDC pourrait être utilisé afin de faire de plus nombreuses transplantations cardiaques au Canada, sauvant ainsi des vies supplémentaires. Bien que des discussions aient permis d'identifier plusieurs obstacles et défis potentiels à la mise en œuvre du don cardiaque après DDC au Canada, il a été déterminé que la mise en œuvre de l'ODP est réalisable (en attente de l'approbation réglementaire pour l'utilisation d'un dispositif de perfusion ex situ chez l'humain) et en accord avec les directives médicales actuelles concernant le DDC. Néanmoins, d'autres travaux sont nécessaires pour évaluer la conformité de la CRN aux politiques canadiennes actuelles de détermination de la mort et pour garantir l'absence de perfusion cérébrale au cours de ce processus.

Ancillary Testing for Determination of Death by Neurologic Criteria Around the World.

OBJECTIVE: We sought to identify similarities and differences in the diagnostic requirements for ancillary testing for determination of brain death/death by neurologic criteria (BD/DNC) around the world. METHODS: We reviewed diagnostic requirements for ancillary testing for BD/DNC in 78 unique official national BD/DNC protocols obtained from contacts worldwide between January 2018 and April 2019. RESULTS: Details provided on the performance and interpretation of ancillary tests for determination of BD/DNC were variably provided and inconsistent. Approximately half of all protocols that included each ancillary test provided details about study performance: 63% of protocols that included conventional cerebral angiography, 55% of protocols that included electroencephalography, 50% of protocols that included somatosensory evoked potentials, 48% of protocols that included transcranial Doppler ultrasonography, 43% of protocols that included nuclear medicine flow study and 41% of protocols that included brainstem auditory evoked potentials. Similarly, about half of all protocols that included each ancillary test provided details about study interpretation: 66% of protocols that included electroencephalography, 59% of protocols that included brainstem auditory evoked potentials, 56% of protocols that included somatosensory evoked potentials, 55% of protocols that included transcranial Doppler ultrasonography, 52% of protocols that included conventional cerebral angiography and 49% of protocols that included nuclear medicine flow study. INTERPRETATION: Diagnostic requirements for ancillary testing in BD/DNC determination vary around the world. We hope that the World Brain Death Project will improve worldwide consensus on the diagnostic requirements for ancillary testing in BD/DNC, both for performance and interpretation.

Determination of Brain Death/Death by Neurologic Criteria: The World Brain Death Project.

IMPORTANCE: There are inconsistencies in concept, criteria, practice, and documentation of brain death/death by neurologic criteria (BD/DNC) both internationally and within countries. OBJECTIVE: To formulate a consensus statement of recommendations on determination of BD/DNC based on review of the literature and expert opinion of a large multidisciplinary, international panel. PROCESS: Relevant international professional societies were recruited to develop recommendations regarding determination of BD/DNC. Literature searches of the Cochrane, Embase, and MEDLINE databases included January 1, 1992, through April 2020 identified pertinent articles for review. Because of the lack of high-quality data from randomized clinical trials or large observational studies, recommendations were formulated based on consensus of contributors and medical societies that represented relevant disciplines, including critical care, neurology, and neurosurgery. EVIDENCE SYNTHESIS: Based on review of the literature and consensus from a large multidisciplinary, international panel, minimum clinical criteria needed to determine BD/DNC in various circumstances were developed. RECOMMENDATIONS: Prior to evaluating a patient for BD/DNC, the patient should have an established neurologic diagnosis that can lead to the complete and irreversible loss of all brain function, and conditions that may confound the clinical examination and diseases that may mimic BD/DNC should be excluded. Determination of BD/DNC can be done with a clinical examination that demonstrates coma, brainstem areflexia, and apnea. This is seen when (1) there is no evidence of arousal or awareness to maximal external stimulation, including noxious visual, auditory, and tactile stimulation; (2) pupils are fixed in a midsize or dilated position and are nonreactive to light; (3) corneal, oculocephalic, and oculovestibular reflexes are absent; (4) there is no facial movement to noxious stimulation; (5) the gag reflex is absent to bilateral posterior pharyngeal stimulation; (6) the cough reflex is absent to deep tracheal suctioning; (7) there is no brain-mediated motor response to noxious stimulation of the limbs; and (8) spontaneous respirations are not observed when apnea test targets reach pH <7.30 and Paco2 ≥60 mm Hg. If the clinical examination cannot be completed, ancillary testing may be considered with blood flow studies or electrophysiologic testing. Special consideration is needed for children, for persons receiving extracorporeal membrane oxygenation, and for those receiving therapeutic hypothermia, as well as for factors such as religious, societal, and cultural perspectives; legal requirements; and resource availability. CONCLUSIONS AND RELEVANCE: This report provides recommendations for the minimum clinical standards for determination of brain death/death by neurologic criteria in adults and children with clear guidance for various clinical circumstances. The recommendations have widespread international society endorsement and can serve to guide professional societies and countries in the revision or development of protocols and procedures for determination of brain death/death by neurologic criteria, leading to greater consistency within and between countries.

Determination of Brain Death/Death by Neurologic Criteria in Countries in Asia and the Pacific.

BACKGROUND AND PURPOSE: We sought to 1) identify countries in Asia and the Pacific that have protocols for the determination of brain death/death by neurologic criteria (BD/DNC) and 2) review the similarities and differences of these protocols in different countries. METHODS: Between January 2018 and April 2019, we attempted to communicate with contacts in the 57 countries in Asia and the Pacific to determine if they had official national BD/DNC protocols. We reviewed and compared the identified protocols. RESULTS: We identified contacts for 40 (70%) of the 57 countries in Asia and the Pacific, and successfully communicated with 37 of them (93% of countries with contacts identified, 65% of countries in Asia and the Pacific). We found that 24 of the 37 countries had BD/DNC protocols. Two (13%) of the 16 protocols that provided a definition of death referred to brainstem death. Kazakhstan and Israel required only 1 examination to declare BD/DNC, while 10 (71%) of the other 14 protocols required 2 examinations separated by 6-48 hours. The prerequisites, clinical examination, apnea testing procedure, and indications for/selection of ancillary tests varied. Ancillary testing was required for all determinations of BD/DNC in five (21%) countries. Thirteen (54%) of the protocols included information about the time of death, while 12 (50%) of them provided instructions about discontinuation of organ support. CONCLUSIONS: The protocols for conducting a BD/DNC determination vary markedly among countries in Asia and the Pacific. Since it is optimal to have internationally and intranationally consistent BD/DNC protocols, efforts should be made to harmonize protocols both within this region and worldwide.

Determination of death by neurologic criteria in Latin American and Caribbean countries.

OBJECTIVES: We sought to (1) identify the countries in the Latin America/Caribbean Group of the United Nations (GRULAC) that have protocols for brain death/death by neurologic criteria (BD/DNC) and (2) review the similarities and differences between these protocols. MATERIALS AND METHODS: Between January 2018 and April 2019, we obtained and reviewed BD/DNC protocols from countries in GRULAC. RESULTS: We communicated with contacts in 30/33 countries in GRULAC (91 % of countries) and found that 16 (53 % of countries with contacts, 48 % of Latin American/Caribbean countries) had BD/DNC protocols. Of the 13 protocols that provided a definition of death, 10 (77 %) referred to whole brain death. The number of exams/examiners, prerequisites for BD/DNC, and descriptions of the clinical assessment and apnea test were inconsistent among protocols. Although Brazil and Panama required an ancillary test, the indications for ancillary testing, and the types of accepted ancillary tests, varied by country. CONCLUSION: BD/DNC determination protocols in the countries in GRULAC are inconsistent. Acknowledging the fact that there are diverse cultural, legal and religious perspectives on death, and human and technological resources differ by region, we recommend that attempts be made to harmonize protocols on BD/DNC both regionally and worldwide.

Determination of death by neurologic criteria around the world.

OBJECTIVE: To identify similarities and differences in protocols on determination of brain death/death by neurologic criteria (BD/DNC) around the world. METHODS: We collected and reviewed official national BD/DNC protocols from contacts around the world between January 2018 and April 2019. RESULTS: We communicated with contacts in 136 countries and found that 83 (61% of countries with contacts identified, 42% of the world) had BD/DNC protocols, 78 of which were unique. Protocols addressed the following prerequisites and provided differing instructions: drug clearance (64, 82%), temperature (61, 78%), laboratory values (56, 72%), observation period (37, 47%), and blood pressure (34, 44%). Protocols did not consistently identify the same components for the clinical examination of brain death; 70 (90%) included coma, 70 (90%) included the pupillary reflex, 68 (87%) included the corneal reflex, 67 (86%) included the oculovestibular reflex, 64 (82%) included the gag reflex, 62 (79%) included the cough reflex, 58 (74%) included the oculocephalic reflex, 37 (47%) included noxious stimulation to the face, and 22 (28%) included noxious stimulation to the limbs. Apnea testing was mentioned in 71 (91%) protocols; there was variability in the technique and target across protocols. Ancillary testing was included as a requirement for all determinations of BD/DNC in 22 (28%) protocols. CONCLUSIONS: There is considerable variability in BD/DNC determination protocols around the world. Medical standards for death should be the same everywhere. We recommend that a worldwide consensus be reached on the minimum standards for BD/DNC.

Maintaining the permanence principle for death during in situ normothermic regional perfusion for donation after circulatory death organ recovery: A United Kingdom and Canadian proposal.

There is international variability in the determination of death. Death in donation after circulatory death (DCD) can be defined by the permanent cessation of brain circulation. Post-mortem interventions that restore brain perfusion should be prohibited as they invalidate the diagnosis of death. Retrieval teams should develop protocols that ensure the continued absence of brain perfusion during DCD organ recovery. In situ normothermic regional perfusion (NRP) or restarting the heart in the donor's body may interrupt the permanent cessation of brain perfusion because, theoretically, collateral circulations may restore it. We propose refinements to current protocols to monitor and exclude brain reperfusion during in situ NRP. In abdominal NRP, complete occlusion of the descending aorta prevents brain perfusion in most cases. Inserting a cannula in the ascending aorta identifies inadequate occlusion of the descending aorta or any collateral flow and diverts flow away from the brain. In thoracoabdominal NRP opening the aortic arch vessels to atmosphere allows collateral flow to be diverted away from the brain, maintaining the permanence standard for death and respecting the dead donor rule. We propose that these hypotheses are correct when using techniques that simultaneously occlude the descending aorta and open the aortic arch vessels to atmosphere.

Barriers and opportunities related to extracorporeal cardiopulmonary resuscitation for out-of-hospital cardiac arrest in Canada: A report from the first meeting of the Canadian ECPR Research Working Group.

For a French translation of the executive summary, please see the Supplementary Material at DOI: 10.1017/cem.2017.429.

Ethics Guide Recommendations for Organ-Donation-Focused Physicians: Endorsed by the Canadian Medical Association.

Donation physicians are specialists with expertise in organ and tissue donation and have been recognized internationally as a key contributor to improving organ and tissue donation services. Subsequent to a 2011 Canadian Critical Care Society-Canadian Blood Services consultation, the donation physician role has been gradually implemented in Canada. These professionals are generally intensive care unit physicians with an enhanced focus and expertise in organ/tissue donation. They must manage the dual obligation of caring for dying patients and their families while providing and/or improving organ donation services. In anticipation of actual, potential or perceived ethical challenges with the role, Canadian Blood Services in partnership with the Canadian Medical Association organized the development of an evidence-informed consensus process of donation experts and bioethicists to produce an ethics guide. This guide includes overarching principles and benefits of the DP role, and recommendations in regard to communication with families, role disclosure, consent discussions, interprofessional conflicts, conscientious objection, death determination, donation specific clinical practices in neurological determination of death and donation after circulatory death, end-of-life care, performance metrics, resources and remuneration. Although this report is intended to inform donation physician practices, it is recognized that the recommendations may have applicability to other professionals (eg, physicians in intensive care, emergency medicine, neurology, neurosurgery, pulmonology) who may also participate in the end-of-life care of potential donors in various clinical settings. It is hoped that this guidance will assist practitioners and their sponsoring organizations in preserving their duty of care, protecting the interests of dying patients, and fulfilling best practices for organ and tissue donation.

International guideline development for the determination of death.

INTRODUCTION AND METHODS: This report summarizes the results of the first phase in the development of international guidelines for death determination, focusing on the biology of death and the dying process, developed by an invitational forum of international content experts and representatives of a number of professional societies. RESULTS AND CONCLUSIONS: Precise terminology was developed in order to improve clarity in death discussion and debate. Critical events in the physiological sequences leading to cessation of neurological and/or circulatory function were constructed. It was agreed that death determination is primarily clinical and recommendations for preconditions, confounding factors, minimum clinical standards and additional testing were made. A single operational definition of human death was developed: 'the permanent loss of capacity for consciousness and all brainstem functions, as a consequence of permanent cessation of circulation or catastrophic brain injury'. In order to complete the project, in the next phase, a broader group of international stakeholders will develop clinical practice guidelines, based on comprehensive reviews and grading of the existing evidence.