Advancing the Scientific Basis for Determining Death in Controlled Organ Donation After Circulatory Determination of Death

In controlled organ donation after circulatory determination of death (cDCDD), accurate and timely death determination is critical, yet knowledge gaps persist. Further research to improve the science of defining and determining death by circulatory criteria is therefore warranted. In a workshop sponsored by the National Heart, Lung, and Blood Institute, experts identified research opportunities pertaining to scientific, conceptual, and ethical understandings of DCDD and associated technologies. This article identifies a research strategy to inform the biomedical definition of death, the criteria for its determination, and circulatory death determination in cDCDD. Highlighting knowledge gaps, we propose that further research is needed to inform the observation period following cessation of circulation in pediatric and neonatal populations, the temporal relationship between the cessation of brain and circulatory function after the withdrawal of life-sustaining measures in all patient populations, and the minimal pulse pressures that sustain brain blood flow, perfusion, activity, and function. Additionally, accurate predictive tools to estimate time to asystole following the withdrawal of treatment and alternative monitoring modalities to establish the cessation of circulatory, brainstem, and brain function are needed. The physiologic and conceptual implications of postmortem interventions that resume circulation in cDCDD donors likewise demand attention to inform organ recovery practices. Finally, because jurisdictionally variable definitions of death and the criteria for its determination may impede collaborative research efforts, further work is required to achieve consensus on the physiologic and conceptual rationale for defining and determining death after circulatory arrest.

Beliefs of physician directors on the management of devastating brain injuries at the Canadian emergency department and intensive care unit interface: a national site-level survey

PURPOSE

Insufficient evidence-based recommendations to guide care for patients with devastating brain injuries (DBIs) leave patients vulnerable to inconsistent practice at the emergency department (ED) and intensive care unit (ICU) interface. We sought to characterize the beliefs of Canadian emergency medicine (EM) and critical care medicine (CCM) physician site directors regarding current management practices for patients with DBI.

METHODS

We conducted a cross-sectional survey of EM and CCM physician directors of adult EDs and ICUs across Canada (December 2022 to March 2023). Our primary outcome was the proportion of respondents who manage (or consult on) patients with DBI in the ED. We conducted subgroup analyses to compare beliefs of EM and CCM physicians.

RESULTS

Of 303 eligible respondents, we received 98 (32%) completed surveys (EM physician directors, 46; CCM physician directors, 52). Most physician directors reported participating in the decision to withdraw life-sustaining measures (WLSM) for patients with DBI in the ED (80%, n = 78), but 63% of these (n = 62) said this was infrequent. Physician directors reported that existing neuroprognostication methods are rarely sufficient to support WLSM in the ED (49%, n = 48) and believed that an ICU stay is required to improve confidence (99%, n = 97). Most (96%, n = 94) felt that providing caregiver visitation time prior to WLSM was a valid reason for ICU admission.

CONCLUSION

In our survey of Canadian EM and CCM physician directors, 80% participated in WLSM in the ED for patients with DBI. Despite this, most supported ICU admission to optimize neuroprognostication and patient-centred end-of-life care, including organ donation.

Knowledge gaps in heart and lung donation after the circulatory determination of death: Report of a workshop of the National Heart, Lung, and Blood Institute

In a workshop sponsored by the U.S. National Heart, Lung, and Blood Institute, experts identified current knowledge gaps and research opportunities in the scientific, conceptual, and ethical understanding of organ donation after the circulatory determination of death and its technologies. To minimize organ injury from warm ischemia and produce better recipient outcomes, innovative techniques to perfuse and oxygenate organs postmortem in situ, such as thoracoabdominal normothermic regional perfusion, are being implemented in several medical centers in the US and elsewhere. These technologies have improved organ outcomes but have raised ethical and legal questions. Re-establishing donor circulation postmortem can be viewed as invalidating the condition of permanent cessation of circulation on which the earlier death determination was made and clamping arch vessels to exclude brain circulation can be viewed as inducing brain death. Alternatively, TA-NRP can be viewed as localized in-situ organ perfusion, not whole-body resuscitation, that does not invalidate death determination. Further scientific, conceptual, and ethical studies, such as those identified in this workshop, can inform and help resolve controversies raised by this practice.

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.

Canadian organ donation organizations' donor audit processes: an environmental scan

PURPOSE

Deceased donor audits (DAs) allow organ donation and transplantation systems to measure and analyze missed donation opportunities (MDOs). Missed donation opportunities can harm both patients/families denied the opportunity to donate and patients on transplant waitlists denied access to lifesaving organs. In Canada, there are no national standards for DAs, data analysis, nor accountability processes surrounding MDOs. Understanding DA current practice in each jurisdicton would facilitate developing a national strategy for DAs.

METHOD

All provincial organ donation organizations (ODOs) were invited to participate in an environmental scan (ES) of current DA practices. The two ES phases were an electronic survey followed by semistructured interviews. We collected information about the objectives, frequency, scope, data collection methodology, resources required, definitions/metrics used, and process for reporting outcomes.

RESULTS

All eleven ODOs participated in both phases of the ES (July and October 2019). The primary purposes for conducting DAs were to estimate the following: 1) donor potential (5/11, 45%); 2) system performance at the provincial level (3/11, 27%); and 3) system performance at the hospital level (3/11, 27%). Frequency of DAs varied from weekly to annually, depending on the availability of death reports, urban vs rural setting, and staffing. High variability was observed in DA methodology, donor definitions, and metrics across jurisdictions.

CONCLUSION

There is significant variability across Canadian ODOs in the methodology, definitions, timeliness, data collection, and reporting of DAs. This underscores the need for a national donor audit strategy to reduce preventable harm from MDOs to patients/families at end of life and those on transplant waitlists.

Dons d’organes et de tissus après décès dans le cadre de l’aide médicale à mourir : mise à jour 2023 du document d’orientation pour l’élaboration de politiques

Contexte:

Depuis la parution du document d’orientation de 2019 de la Société canadienne du sang (SCS) pour les dons d’organes et de tissus après décès dans le cadre de l’aide médicale à mourir (AMM), le gouvernement fédéral a apporté des amendements à sa loi sur l’AMM. La présente mise à jour s’adresse aux médecins, aux organismes de don d’organes, aux spécialistes des soins de fin de vie et de l’AMM et aux responsables des orientations politiques; on y explique les répercussions de ces amendements.

Méthodes:

La Société canadienne du sang a réuni un groupe de 63 spécialistes de divers domaines (soins intensifs, dons d’organes et de tissus, administration des services de santé, AMM, bioéthique, droit et recherche) pour faire le point sur ces changements à l’occasion de son Forum d’orientation sur le don d’organes et de tissus après décès dans le cadre de l’aide médicale à mourir. Deux personnes admissibles à l’AMM et 2 proches de personnes ayant fait un don d’organe après l’AMM y ont aussi participé. Dans le cadre de 3 réunions consécutives tenues en ligne entre juin 2021 et avril 2022, les personnes participant au Forum ont abordé divers sujets en grands et petits groupes. Les discussions ont été guidées par une revue documentaire publiée selon la méthodologie JBI. Nous avons utilisé une technique du groupe nominal adaptée pour rédiger les recommandations qui ont fait consensus. La gestion des intérêts concurrents s’est faite selon les principes du Guidelines International Network, un réseau international qui se consacre aux lignes directrices de pratique clinique.

Recommandations:

Même si bon nombre des recommandations du document d’orientation de 2019 demeurent pertinentes, la présente mise à jour a permis d’en actualiser 2 et d’en formuler 8 nouvelles dans les domaines suivants : aiguillage vers un organisme de don d’organes, consentement, dons dirigés et conditionnels, procédure d’AMM, détermination du décès, équipes soignantes et préparation de rapports.

Interprétation:

Les politiques et les pratiques en matière de don d’organes et de tissus après l’AMM au Canada doivent être conformes à la législation canadienne actuelle. La mise à jour de ce document d’orientation aidera les médecins à s’y retrouver parmi les enjeux médicaux, juridiques et éthiques inhérents à leur travail auprès de personnes qui souhaitent faire un don d’organes après l’AMM.

Sociodemographic Variables in Canadian Organ Donation Organizations: A Health Information Survey

Health systems must collect equity-relevant sociodemographic variables to measure and mitigate health inequities. The specific variables collected by organ donation organizations (ODOs) across Canada, variable definitions, and processes of the collection are not defined. We undertook a national health information survey of all ODOs in Canada. These results will inform the development of a standard national dataset of equity-relevant sociodemographic variables.

Methods

We conducted an electronic, self-administered cross-sectional survey of all ODOs in Canada from November 2021 to January 2022. We targeted key knowledge holders familiar with the data collection processes within each Canadian ODO known to Canadian Blood Services. Categorical item responses are presented as numbers and proportions.

Results

We achieved a 100% response rate from 10 Canadian ODOs. Most data were collected by organ donation coordinators. Only 2 of 10 ODOs reported using scripts explaining why sociodemographic data are being collected or incorporated training in cultural sensitivity for any given variable. A lack of cultural sensitivity training was endorsed by 50% of respondents as a barrier to the collection of sociodemographic variables by ODOs, whereas 40% of respondents identified a lack of training in sociodemographic variable collection as a significant barrier.

Conclusions

Few programs routinely collect sufficient data to examine health inequities with an intersectional lens. Most data collection occurs midway through the ODO interaction, creating a missed opportunity to better understand differences in social identities of patients who register their intention to donate in advance or who decline the donation. National standardization of equity-relevant data collection definitions and processes of the collection is needed.

Deceased organ and tissue donation after medical assistance in dying: 2023 updated guidance for policy

BACKGROUND

Since Canadian Blood Services (CBS) developed policy guidance in 2019 for organ and tissue donation after medical assistance in dying (MAiD), the federal government has made changes to legislation related to MAiD. This document provides updated guidance for clinicians, organ donation organizations, end-of-life care experts, MAiD providers and policy-makers on the impact of these changes.

METHODS

Canadian Blood Services assembled a group of 63 experts from critical care, organ and tissue donation, health care administration, MAiD, bioethics, law and research to review the legislative changes in the Organ and Tissue Donation After Medical Assistance in Dying - Guidance for Policy forum. Two patients who had requested and been found eligible for MAiD and 2 family members of patients who had donated organs after MAiD were also included as participants. In a series of 3 online meetings from June 2021 to April 2022, forum participants addressed a variety of topics in small and large groups. These discussions were informed by a comprehensive scoping review using JBI methodology. We used an adapted form of nominal group technique to develop the recommendations, which were approved by consensus of the participants. Management of competing interests was in accordance with Guideline International Network principles.

RECOMMENDATIONS

Although many of the recommendations from the guidance developed in 2019 are still relevant, this guidance provides 2 updated recommendations and 8 new recommendations in the following areas: referral to an organ donation organization, consent, directed and conditional donation, MAiD procedures, determination of death, health care professionals and reporting.

INTERPRETATION

Policies and practices for organ and tissue donation after MAiD in Canada should align with current Canadian legislation. This updated guidance will help clinicians navigate the medical, legal and ethical challenges that arise when they support patients pursuing donation after MAiD.

Newborns with a Congenital Heart Defect and Diastolic Steal Have an Altered Cerebral Arterial Doppler Profile

OBJECTIVES

To compare trends in the anterior cerebral artery (ACA) Doppler markers of vascular flow for neonates with a congenital heart defect (CHD) with and without diastolic systemic steal during the first 7 days of life.

METHODS

Prospective study recruiting newborns (≥35 weeks of gestation) with a CHD. Doppler ultrasound and echocardiography were performed daily from day 1 to 7. The cohort was divided into the presence/absence of holo-diastolic retrograde flow in the postductal aorta ("retrograde") on the last-available echocardiogram. Data extractors were masked to retrograde status. Mixed effect models (random slope/intercept) were constructed using RStudio.

RESULTS

We enrolled 38 neonates with CHD. Retrograde aortic flow was present on the last echocardiogram in 23 (61%). Peak systolic velocity and mean velocity increased significantly over time, independent of retrograde status. However, having a "retrograde" flow status conferred a significant decrease over time of their ACA-end-diastolic velocity (β = -5.75 cm/s, 95% CI -8.38 to -3.12, P < .001, when compared with the nonretrograde group), and a significant increase in the ACA resistive (β = 0.16, 95% CI 0.10-0.22, P < .001) and pulsatility (β = 0.49, 95% CI 0.28-0.69, P < .001) indexes. No subject presented retrograde diastolic flow in the ACA.

CONCLUSIONS

In neonates with CHD in the first week of life, infants with echocardiographic signs of systemic diastolic steal within the pulmonary circulation have Doppler signs of cerebrovascular steal in the ACA.

International Donation and Transplantation Legislative and Policy Forum: Methods and Purpose

Organ and tissue donation and transplantation (OTDT) legislation and policies vary around the world, and this variability contributes to discrepancies in system performance. This article describes the purpose and methodology of an international forum that was organized to create consensus recommendations related to key legal and policy attributes of an ideal OTDT system. The intent is to create guidance for legislators, regulators, and other system stakeholders who aim to create or reform OTDT legislation and policy.

Methods

This Forum was initiated by Transplant Québec and cohosted by the Canadian Donation and Transplantation Program partnered with multiple national and international donation and transplantation organizations. Seven domains were identified by the scientific committee' and domain working groups identified specific topics for recommendations: Baseline Ethical Principles, Legal Foundations, Consent Model and Emerging Legal Issues, Donation System Architecture, Living Donation, Tissue Donation, and Research and Innovation Systems and Emerging Issues. Patient, family, and donor partners were integrated into every stage of the planning and execution of the Forum. Sixty-one participants from 13 countries contributed to recommendation generation. Topic identification and recommendation consensus was completed over a series of virtual meetings from March to September 2021. Consensus was achieved by applying the nominal group technique informed by literature reviews performed by participants. Recommendations were presented at a hybrid in-person and virtual forum in Montreal, Canada, in October 2021.

Output

Ninety-four recommendations (9-33 per domain) and an ethical framework for evaluating new policies were developed during the Forum proceedings. The accompanying articles include the recommendations from each domain and justifications that link the consensus to existing literature and ethical or legal concepts.

Conclusions

Although the recommendations could not account for the vast global diversity of populations, healthcare infrastructure, and resources available to OTDT systems, they were written to be as widely applicable as possible.

Preventable harm in the Canadian organ donation and transplantation system: a descriptive study of missed organ donor identification and referral

PURPOSE

Deceased organ donation is predicated on timely identification and referral (IDR) of potential organ donors. Many Canadian provinces have legislated mandatory referral of potential deceased donors. Untimely or missed IDRs are safety events where best or expected practice has not occurred causing preventable harm to patients and denying families the opportunity of donation at end of life (EOL) as well as denying transplant waitlist patients access to lifesaving organs.

METHODS

We requested donor definitions and data to calculate IDR, consent, and approach rates from all Canadian organ donation organizations (ODOs) for 2016-2018. We then estimated the number of missed IDR patients who were eligible for approach (safety events) and the associated preventable harm to patients at EOL and on transplant waitlists.

RESULTS

Annually, there were 63-76 missed IDR patients eligible for approach (3.6-4.5 per million population [PMP]) from four ODOs-three with mandatory referral legislation. Applying each ODO's approach and consent rates for the corresponding year, there were 37-41 missed donors (2.4 donor PMP) annually. Assuming three transplants per donor, the theoretical number of missed transplants would be 111-123 (6.4-7.3 transplants PMP) annually.

CONCLUSIONS

Data from four Canadian ODOs show that missed IDR safety events resulted in important preventable harm measured by a lost opportunity for donation of 2.4 donors PMP annually and 354 potentially missed transplants between 2016 and 2018. Given that 223 patients died on Canada's waitlist in 2018, national donor audits and quality improvement initiatives to optimize IDR are essential to reduce preventable harm to these vulnerable populations.

When is a person dead? The Canadian public's understanding of death and death determination: a nationwide survey

PURPOSE

We aimed to describe the Canadian public's understanding and perception of how death is determined in Canada, their level of interest in learning about death and death determination, and their preferred strategies for informing the public.

METHODS

We conducted a nationwide cross-sectional survey of a representative sample of the Canadian public. The survey presented two scenarios of a man who met current criteria for neurologic death determination (scenario 1) and a man who met current criteria for circulatory death determination (scenario 2). Survey questions evaluated understanding of how death is determined, acceptance of death determination by neurologic and circulatory criteria, and interest and preferred strategies in learning more about the topic.

RESULTS

Among 2,000 respondents (50.8% women; n = 1,015), nearly 67.2% believed that the man in scenario 1 was dead (n = 1,344) and 81.2% (n = 1,623) believed that the man in scenario 2 was dead. Respondents who believed that the man was not dead or were unsure endorsed several factors that may increase their agreement with the determination of death, including requiring more information about how death was determined, seeing the results of brain imaging/tests, and a third doctor's opinion. Predictors of disbelief that the man in scenario 1 is dead were younger age, being uncomfortable with the topic of death, and subscribing to a religion. Predictors of disbelief that the man in scenario 2 is dead were younger age, residing in Quebec (compared with Ontario), having a high school education, and subscribing to a religion. Most respondents (63.3%) indicated interest in learning more about death and death determination. Most respondents preferred to receive information about death and death determination from their health care professional (50.9%) and written information provided by their health care professional (42.7%).

CONCLUSION

Among the Canadian public, the understanding of neurologic and circulatory death determination is variable. More uncertainty exists with death determination by neurologic criteria than with circulatory criteria. Nevertheless, there is a high level of general interest in learning more about how death is determined in Canada. These findings provide important opportunities for further public engagement.

Diagnostic accuracy of ancillary tests for death by neurologic criteria: a systematic review and meta-analysis

PURPOSE

Ancillary tests are frequently used in death determination by neurologic criteria (DNC), particularly when the clinical neurologic examination is unreliable. Nevertheless, their diagnostic accuracy has not been extensively studied. Our objective was to synthesize the sensitivity and specificity of commonly used ancillary tests for DNC.

SOURCE

We performed a systematic review and meta-analysis by searching MEDLINE, EMBASE, Cochrane databases, and CINAHL Ebsco from their inception to 4 February 2022. We selected cohort and case-control studies including patients with 1) clinically diagnosed death by neurologic criteria or 2) clinically suspected death by neurologic criteria who underwent ancillary testing for DNC. We excluded studies without a priori diagnostic criteria and studies conducted solely on pediatric patients. Accepted reference standards were clinical examination, four-vessel conventional angiography, and radionuclide imaging. Data were directly extracted from published reports. We assessed the methodological quality of studies with the QUADAS-2 tool and estimated ancillary test sensitivities and specificities using hierarchical Bayesian models with diffuse priors.

PRINCIPAL FINDINGS

Overall, 137 records met the selection criteria. One study (0.7%) had a low risk of bias in all QUADAS-2 domains. Among clinically diagnosed death by neurologic criteria patients (n = 8,891), ancillary tests had similar pooled sensitivities (range, 0.82-0.93). Sensitivity heterogeneity was greater within (σ = 0.10-0.15) than between (σ = 0.04) ancillary test types. Among clinically suspected death by neurologic criteria patients (n = 2,732), pooled ancillary test sensitivities ranged between 0.81 and 1.00 and specificities between 0.87 and 1.00. Most estimates had high statistical uncertainty.

CONCLUSION

Studies assessing ancillary test diagnostic accuracy have an unclear or high risk of bias. High-quality studies are required to thoroughly validate ancillary tests for DNC.

STUDY REGISTRATION

PROSPERO (CRD42013005907); registered 7 October 2013.

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.

Death determination by neurologic criteria-what do families understand?

PURPOSE

Currently, there is little empirical data on family understanding about brain death and death determination. The purpose of this study was to describe family members' (FMs') understanding of brain death and the process of determining death in the context of organ donation in Canadian intensive care units (ICUs).

METHODS

We conducted a qualitative study using semistructured, in-depth interviews with FMs who were asked to make an organ donation decision on behalf of adult or pediatric patients with death determination by neurologic criteria (DNC) in Canadian ICUs.

RESULTS

From interviews with 179 FMs, six main themes emerged: 1) state of mind, 2) communication, 3) DNC may be counterintuitive, 4) preparation for the DNC clinical assessment, 5) DNC clinical assessment, and 6) time of death. Recommendations on how clinicians can help FMs to understand and accept DNC through communication at key moments were described including preparing FMs for death determination, allowing FMs to be present, and explaining the legal time of death, combined with multimodal strategies. For many FMs, understanding of DNC unfolded over time, facilitated with repeated encounters and explanation, rather than during a single meeting.

CONCLUSION

Family members' understanding of brain death and death determination represented a journey that they reported in sequential meeting with health care providers, most notably physicians. Modifiable factors to improve communication and bereavement outcomes during DNC include attention to the state of mind of the family, pacing and repeating discussions according to families' expressed understanding, and preparing and inviting families to be present for the clinical determination including apnea testing. We have provided family-generated recommendations that are pragmatic and can be easily implemented.

Infratentorial brain injury and death by neurologic criteria in Canada: a narrative review

There are two anatomic formulations of death by neurologic criteria accepted worldwide: whole-brain death and brainstem death. As part of the Canadian Death Definition and Determination Project, we convened an expert working group and performed a narrative review of the literature. Infratentorial brain injury (IBI) with an unconfounded clinical assessment consistent with death by neurologic criteria represents a nonrecoverable injury. The clinical determination of death cannot distinguish between IBI and whole-brain cessation of function. Current clinical, functional, and neuroimaging assessments cannot reliably confirm the complete and permanent destruction of the brainstem. No patient with isolated brainstem death has been reported to recover consciousness and all patients have died. Studies suggest a significant majority of isolated brainstem death will evolve into whole-brain death, influenced by time/duration of somatic support and impacted by ventricular drainage and/or posterior fossa decompressive craniectomy. Acknowledging variability in intensive care unit (ICU) physician opinion on this matter, a majority of Canadian ICU physicians would perform ancillary testing for death determination by neurologic criteria in the context of IBI. There is currently no reliable ancillary test to confirm complete destruction of the brainstem; ancillary testing currently includes evaluation of both infratentorial and supratentorial flow. Acknowledging international variability in this regard, the existing evidence reviewed does not provide sufficient confidence that the clinical exam in IBI represents a complete and permanent destruction of the reticular activating system and thus the capacity for consciousness. On this basis, IBI consistent with clinical signs of death by neurologic criteria without significant supratentorial involvement does not fulfill criteria for death in Canada and ancillary testing is required.

Delayed recovery from severe refractory intracranial hypertension due to expansion of skin and pericranium stretch after decompressive craniectomy

PURPOSE

Decompressive craniectomy immediately reduces intracranial pressure by increasing space to accommodate brain volumes. Any delay in reduction of pressure and signs of severe intracranial hypertension requires explanation.

CLINICAL FEATURES

We present the case of a 13-yr-old boy presenting with a ruptured arteriovenous malformation resulting in a massive occipito-parietal hematoma and increased intracranial pressure (ICP) refractory to medical management. This patient ultimately underwent a decompressive craniectomy (DC) for alleviation of increased ICP, despite which the patient's hemorrhage continued to worsen to the point of brainstem areflexia suggestive of possible progression to brain death. Within hours of the decompressive craniectomy, the patient displayed a relatively sudden, marked improvement in clinical status, most notably a return in pupillary reactivity and significant decrease in measured ICP. A review of postoperative images after the decompressive craniectomy suggested increases in brain volume that continued beyond the initial postoperative period.

CONCLUSION

We urge caution to be taken in the interpretation of the neurologic examination and measured ICP in the context of a decompressive craniectomy. In the patient described in this Case Report, we propose that ongoing expansion of brain volume following a decompressive craniectomy beyond the initial postoperative period, possibly secondary to the stretch of skin or pericranium (used as a dural substitute for expansile duraplasty), can explain further clinical improvements beyond the initial postoperative period. We call for routine serial analyses of brain volumes after decompressive craniectomy to confirm these findings.

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.

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.

Inequities in organ and tissue donation and transplantation for sexual orientation and gender identity diverse people: A scoping review

Sexual orientation and gender identity (SOGI) diverse populations experience discrimination in organ and tissue donation and transplantation (OTDT) systems globally. We assembled a multidisciplinary group of clinical experts as well as SOGI-diverse patient and public partners and conducted a scoping review including citations on the experiences of SOGI-diverse persons in OTDT systems globally to identify and explore the inequities that exist with regards to living and deceased OTDT. Using scoping review methods, we conducted a systematic literature search of relevant electronic databases from 1970-2021 including a grey literature search. We identified and screened 2402 references and included 87 unique publications. Two researchers independently coded data in included publications in duplicate. We conducted a best-fit framework synthesis paired with an inductive thematic analysis to identify synthesized benefits, harms, inequities, justification of inequities, recommendations to mitigate inequities, laws and regulations, as well as knowledge and implementation gaps regarding SOGI-diverse identities in OTDT systems. We identified numerous harms and inequities for SOGI-diverse populations in OTDT systems. There were no published benefits of SOGI-diverse identities in OTDT systems. We summarized recommendations for the promotion of equity for SOGI-diverse populations and identified gaps that can serve as targets for action moving forward.

Infratentorial Brain Injury Among Patients Suspected of Death by Neurologic Criteria: A Systematic Review and Meta-analysis

BACKGROUND AND OBJECTIVES

There is a paucity of data on the frequency and prognosis of infratentorial brain injury among patients suspected of death by neurologic criteria (DNC), which likely contributes to scientific uncertainty regarding the role of isolated brainstem death in DNC determination. Our aim was to synthesize the prevalence, characteristics, and evolution of infratentorial brain injury, including isolated brainstem death, among patients suspected of DNC.

METHODS

We conducted a systematic review by searching Medline, Embase, EBM Reviews, CINAHL Complete, and the gray literature from inception to March 26, 2021. We selected cohort and cross-sectional studies, case reports, and case series that included patients suspected of DNC. Two study investigators independently performed study selection, data collection, and risk of bias assessment. Our primary outcomes were the respective prevalence of infratentorial brain injury and isolated brainstem death, which we meta-analyzed using mixed-effects Bayesian hierarchical models with diffuse priors. Our secondary outcomes were the characteristics and evolution of patients with infratentorial brain injury and isolated brainstem death.

RESULTS

Twenty-one studies met the selection criteria, most of which were of moderate to high risk of bias. Among patients suspected of DNC, the prevalence of infratentorial brain injury ranged from 2% to 16% (n = 3,602, mean prevalence: 6.3%, 95% highest density interval [2.4%-14.2%]), whereas the prevalence of isolated brainstem death ranged from 1% to 4% (n = 3,692, mean prevalence: 1.5%, 95% highest density interval [0.5%-3.9%]). A total of 38 isolated brainstem death cases with data on clinical characteristics and/or evolution were included. All had infratentorial strokes. Twenty patients had EEG background activity in the α or θ frequencies, 19 had preserved cerebral blood flow, 2 had preserved supratentorial cerebral perfusion, 2 had cortical responses to visual evoked potentials, and 1 had cortical responses to somatosensory evoked potentials. At the latest follow-up, 28 had progressed to whole-brain death.

DISCUSSION

Studies with moderate to high risk of bias suggest that infratentorial brain injury is relatively uncommon among patients suspected of DNC. Isolated brainstem death is rarer and seems to carry a high risk of progression to whole-brain death. These findings require further high-quality investigation.

Public Understandings of the Definition and Determination of Death: A Scoping Review

Background.

Advances in medicine and technology that have made it possible to support, repair, or replace failing organs challenge commonly held notions of life and death. The objective of this review is to develop a comprehensive description of the current understandings of the public regarding the meaning/definition and determination of death.

Methods.

This scoping review was conducted in compliance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews checklist. Online databases were used to identify articles published from 2003 to 2021. Two reviewers (S.S. and K.Z.) screened the articles using predefined inclusion and exclusion criteria, extracted data for specific content variables, and performed descriptive examination. Complementary searches of reference lists complemented the final study selection. A search strategy using vocabulary of the respective databases was created, and criteria for the inclusion and exclusion of the articles were established.

Results.

Seven thousand four hundred twenty-eight references were identified. Sixty were retained for analysis, with 4 additional references added from complementary searches. A data extraction instrument was developed to iteratively chart the results. A qualitative approach was conducted to thematically analyze the data. Themes included public understanding/attitudes toward death and determination of death (neurological determination and cardiocirculatory determination of death), death and organ donation, public trust and legal variability, and media impacts.

Conclusions.

This review provides a current and comprehensive overview of the literature related to the general public’s understanding and attitudes toward death and death determination and serves to highlight the gaps in this topic.

Clinical evaluation and ancillary testing for the diagnosis of death by neurologic criteria: a cross-sectional survey of Canadian intensivists

PURPOSE

Trust in the deceased organ donation process relies on the expectation that the diagnosis of death by neurologic criteria (DNC) is accurate and reliable. The objective of this study was to assess the perceptions and approaches to DNC diagnosis among Canadian intensivists.

METHODS

We conducted a self-administered, online, cross-sectional survey of Canadian intensivists. Our sampling frame included all intensivists practicing in Canadian institutions. Results are reported using descriptive statistics.

RESULTS

Among 550 identified intensivists, 249 (45%) completed the survey. Respondents indicated they would be comfortable diagnosing DNC based on clinical criteria alone in cases where there is movement in response to stimulation (119/248; 48%); inability to evaluate upper/lower extremity responses (84/249; 34%); spontaneous peripheral movement (76/249; 31%); inability to evaluate both oculocephalic and oculo-caloric reflexes (40/249; 16%); presence of high cervical spinal cord injury (40/249; 16%); and within 24 hr of hypoxemic-ischemic brain injury (38/247; 15%). Most respondents agreed that an ancillary test should always be conducted when a complete clinical evaluation is impossible (225/241; 93%); when there is possibility of a residual sedative effect (216/242; 89%); when the mechanism for brain injury is unclear (172/241; 71%); and if isolated brainstem injury is suspected (142/242; 59%). Sixty-six percent (158/241) believed that ancillary tests are sensitive and 55% (132/241) that they are specific for DNC. Respondents considered the following ancillary tests useful for DNC: four-vessel conventional angiography (211/241; 88%), nuclear imaging (179/240; 75%), computed tomography (CT) angiography (156/240; 65%), and CT perfusion (134/240; 56%).

CONCLUSION

There is variability in perceptions and approaches to DNC diagnosis among Canadian intensivists, and some practices are inconsistent with national recommendations.

The variable impact of the overdose crisis on organ donation among five Canadian provinces: a retrospective study

BACKGROUND

While most overdose deaths in Canada occur in the community, some patients are resuscitated, admitted to intensive care units having sustained severe anoxic brain injury, and have the potential to be organ donors. The purpose of this study was to determine the impact of the overdose crisis on organ donation in selected Canadian provinces.

METHODS

We obtained data on the total number of organ donors and those dying because of overdose in five Canadian provinces from 2014 to 2018. We also obtained data for January-June 2019 for four of five provinces (Quebec excepted). We accessed federal and provincial data on the number of overdose deaths and compared the proportion of organ donors who died of an overdose both over time and between provinces. The number of organ transplants resulting from donors dying of an overdose from three provinces was also determined.

RESULTS

From 2014 to 2017, there was a 35% increase (554 to 747) in total deceased organ donors but a 294% increase (31 to 122) in organ donors dying of an overdose. While the proportion of organ donors dying from an overdose increased overall, this varied from 35% (42 of 121) in British Columbia to < 5% in both Quebec (9 of 182) and Nova Scotia (< 2 of 16). There were 1,043 organ transplants resulting from organ donors dying of overdose in BC, Ontario and Alberta although only 2.5-3.5% (297 of 10,858) of those dying of an overdose became organ donors.

CONCLUSIONS

There has been an increase in organ donors dying from drug overdose in Canada. Regional variation mirrors differences in total opiate-related death.

A qualitative exploratory case series of patient and family experiences with ECPR for out-of-hospital cardiac arrest

Objective

There is currently no existing data examining the opinions of patients and families after treatment with extracorporeal cardiopulmonary resuscitation (ECPR) for out-of-hospital cardiac arrest (OHCA). We sought to interview family members and patients to learn from their experiences and satisfaction with treatment.

Methods

We contacted family members and survivors for all cases treated with ECPR for refractory OHCA at St. Paul’s Hospital between January 2014 and July 2018. We performed semi-structured interviews with participants, specifically within the topics of: information sharing (including impressions of an ECPR informational pamphlet), prognostication, organ donation, and perceived value of ECPR. Due to low participant enrolment, we described all interviews in a narrative approach.

Results

Within the study period, there were 23 OHCAs treated with ECPR; two survivors and three family members agreed to participate. Participants were satisfied with the treatment provided, including information sharing and prognostication. There were mixed opinions about the best method of information-sharing (verbal vs written), as well as the timing of organ donation conversations. All participants believed ECPR for OHCA to be of high value.

Conclusion

Patient’s conveyed satisfaction with ECPR treatment, with mixed views on the best information sharing strategy. Further study is needed to define the optimal methods and timing for discussions of organ donation, especially for treatments of with a relatively low likelihood success.

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.

Current Use, Capacity, and Perceived Barriers to the Use of Extracorporeal Cardiopulmonary Resuscitation for Out-of-Hospital Cardiac Arrest in Canada

BACKGROUND

Extracorporeal cardiopulmonary resuscitation (ECPR) is a therapeutic option for refractory cardiac arrest. We sought to perform an environmental scan to describe ECPR utilization in Canada and perceived barriers for application to out-of-hospital cardiac arrest (OHCA).

METHODS

This was a national cross-sectional study. We identified all cardiovascular surgery- and extracorporeal membrane oxygenation (ECMO)-capable hospitals in Canada and emergency medical services (EMS) agencies delivering patients to those centres. We requested the medical lead from each hospital's ECMO service and each EMS agency to submit data regarding ECMO and ECPR utilization, as well as perceived barriers to ECPR provision for OHCA.

RESULTS

We identified and received survey data from 39 of 39 Canadian hospital institutions and 21 of 22 EMS agencies. Of hospitals, 38 (97%) perform ECMO and 27 (69%) perform ECPR (74% of which perform ≤5 cases per year). Of the 18 (46%) sites offering ECPR for OHCA, 8 apply a formal protocol for eligibility and initiation procedures. EMS agencies demonstrate heterogeneity with intra-arrest transport practices. The primary rationale for nontransport of refractory OHCA is that hospital-based care offers no additional therapies. Perceived barriers to the use of ECPR for OHCA were primarily related to limited evidence supporting its use, rather than resources required.

CONCLUSION

Many Canadian cardiovascular surgery- or ECMO-equipped hospitals use ECPR; roughly half employ ECPR for OHCAs. Low case volumes and few formal protocols indicate that this is not a standardized therapy option in most centres. Increased application may be dependent on a stronger evidence base including data from randomized clinical trials currently underway.

Expanding controlled donation after the circulatory determination of death: statement from an international collaborative

A decision to withdraw life-sustaining treatment (WLST) is derived by a conclusion that further treatment will not enable a patient to survive or will not produce a functional outcome with acceptable quality of life that the patient and the treating team regard as beneficial. Although many hospitalized patients die under such circumstances, controlled donation after the circulatory determination of death (cDCDD) programs have been developed only in a reduced number of countries. This International Collaborative Statement aims at expanding cDCDD in the world to help countries progress towards self-sufficiency in transplantation and offer more patients the opportunity of organ donation. The Statement addresses three fundamental aspects of the cDCDD pathway. First, it describes the process of determining a prognosis that justifies the WLST, a decision that should be prior to and independent of any consideration of organ donation and in which transplant professionals must not participate. Second, the Statement establishes the permanent cessation of circulation to the brain as the standard to determine death by circulatory criteria. Death may be declared after an elapsed observation period of 5 min without circulation to the brain, which confirms that the absence of circulation to the brain is permanent. Finally, the Statement highlights the value of perfusion repair for increasing the success of cDCDD organ transplantation. cDCDD protocols may utilize either in situ or ex situ perfusion consistent with the practice of each country. Methods to accomplish the in situ normothermic reperfusion of organs must preclude the restoration of brain perfusion to not invalidate the determination of death.

Resumption of Cardiac Activity after Withdrawal of Life-Sustaining Measures

BACKGROUND

The minimum duration of pulselessness required before organ donation after circulatory determination of death has not been well studied.

METHODS

We conducted a prospective observational study of the incidence and timing of resumption of cardiac electrical and pulsatile activity in adults who died after planned withdrawal of life-sustaining measures in 20 intensive care units in three countries. Patients were intended to be monitored for 30 minutes after determination of death. Clinicians at the bedside reported resumption of cardiac activity prospectively. Continuous blood-pressure and electrocardiographic (ECG) waveforms were recorded and reviewed retrospectively to confirm bedside observations and to determine whether there were additional instances of resumption of cardiac activity.

RESULTS

A total of 1999 patients were screened, and 631 were included in the study. Clinically reported resumption of cardiac activity, respiratory movement, or both that was confirmed by waveform analysis occurred in 5 patients (1%). Retrospective analysis of ECG and blood-pressure waveforms from 480 patients identified 67 instances (14%) with resumption of cardiac activity after a period of pulselessness, including the 5 reported by bedside clinicians. The longest duration after pulselessness before resumption of cardiac activity was 4 minutes 20 seconds. The last QRS complex coincided with the last arterial pulse in 19% of the patients.

CONCLUSIONS

After withdrawal of life-sustaining measures, transient resumption of at least one cycle of cardiac activity after pulselessness occurred in 14% of patients according to retrospective analysis of waveforms; only 1% of such resumptions were identified at the bedside. These events occurred within 4 minutes 20 seconds after a period of pulselessness. (Funded by the Canadian Institutes for Health Research and others.).

Summary of International Recommendations for Donation and Transplantation Programs During the Coronavirus Disease Pandemic

BACKGROUND

The COVID-19 pandemic has disrupted all aspects of the international organ donation and transplantation (ODT) system. Multiple organizations have developed guidance, but to date, no comparative summary has emerged to understand differences in existing recommendations.

METHODS

We developed and applied a comparative methodology to a convenience sample of recommendations available on The Transplantation Society website. Document types were classified according to characteristics such as type of organization (eg, governing body or professional society) and geographic region. Recommendations were grouped according to content, and summaries were posted on a public website. This process is ongoing and will be updated as new recommendations become available.

RESULTS

Eighteen documents were extracted in the initial review. All documents were based on expert opinion, and none described a formal literature review or adherence with clinical guideline development processes. Recommendation categories included screening of potential donors, risk assessment of potential recipients, posttransplant risk, living/paired donation, protection of ODT professionals, and ethics/logistics. While many documents included similar recommendations, such as the need to screen and test patients who are potential donors, there was variation on some topics. Type of recommended laboratory testing varied with 64% recommending nasopharyngeal swabs, 43% oropharyngeal, and 24% bronchial aspirates. Updated results are available at https://cdtrp.ca/en/covid-19-international-recommendations-for-odt/.

CONCLUSIONS

The current state of COVID-19 ODT recommendations is limited to expert opinion. Substantial variation exists regarding recommendations, which are based on emerging but currently low-quality evidence. This summary of existing recommendations will serve to inform priorities for evidence-based recommendations.

Patient engagement in a Canadian consensus forum for heart donation after circulatory determination of death

PURPOSE

Heart donation and transplantation following circulatory determination of death has yet to be performed in Canada. A consensus forum was held to provide expert guidance to inform policy with a comprehensive patient partner strategy. This paper describes the process used to create fulsome patient partner engagement resulting in mutually beneficial policy development in this complex area.

METHODS

A wide-ranging process for involving patient partners in this area included pre-meeting education, in-meeting expert support, full participation and permission to step back if desired, and post-meeting debriefing. Following the meeting, a questionnaire was used to guide a debrief discussion with patient partners and steering committee members who co-authored this paper.

RESULTS

Five key themes arose that echoed the sentiments and contributions made by patient partners, including: 1) a strong desire to improve the system, 2) gratitude and honour, 3) expert support and process, 4) simplification of complex concepts, and 5) mutual benefit expressed by patient partners and healthcare professionals.

CONCLUSION

Despite the complexity of the content and the emotionally sensitive nature of discussions around deceased organ donation, a well-planned strategy to involve patient partners is important, impactful, and central to the process. This suggests a broad interprofessional audience can engage with properly prepared and supported patient partners to strengthen and focus dialogue and outputs in the development of health policy in the donation and transplant sector.

Survey of Canadian critical care physicians' knowledge and attitudes towards legislative aspects of the deceased organ donation system

PURPOSE

We surveyed Canadian critical care physicians who may care for patients who are potential organ donors to understand their attitudes and knowledge of legislation governing the deceased organ donation system.

METHODS

We used a web-based, self-administered survey that included questions related to opt-out consent and mandatory referral legislation. Potential participants were identified through membership lists of professional societies and manual searches. We designed our survey using standardized methods and administered it in February and March 2018.

RESULTS

Fifty percent (263/529) of potential participants completed the questionnaire. A majority (61%; 144/235) supported a change towards an opt-out consent model, and 77% (181/235) stated they believe it would increase donation rates. Asked if opt-out consent would change their practices, 71% (166/235) stated an opt-out model would not change how or if they approach families to discuss donation. Fifty-six percent (139/249) supported mandatory referral laws, while only 42% (93/219) of those working in provinces with mandatory referral correctly stated that such laws exist in their province. Respondents gave variable responses on who should be accountable when patients are not referred, and 16% (40/249) believed no one should be held accountable.

CONCLUSIONS

While a majority of critical care physicians supported opt-out consent and mandatory referral, many were neutral or against it. Many were unaware of existing laws and had variable opinions on how to ensure accountability. Efforts to increase understanding of how legislative models influence practice are required for any law to achieve its desired effect.

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.

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.