No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
Aligning the Criterion and Tests for Brain Death
Abstract
Disturbing cases continue to be published of patients declared brain dead who later were found to have a few intact brain functions. We address the reasons for the mismatch between the whole-brain criterion and brain death tests, and suggest solutions. Many of the cases result from diagnostic errors in brain death determination. Others probably result from a tiny amount of residual blood flow to the brain despite intracranial circulatory arrest. Strategies to lessen the mismatch include improving brain death determination training for physicians, mandating a test showing complete intracranial circulatory arrest, or revising the whole-brain criterion.
... B rain death (BD) has been progressively wide-reaching accepted beginning since the late 1950s. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] BD outlines medical and legal standards, and its determination is based on guidelines for children, [21] and adults, [22] that established an orderly set of clinical criteria assessed at the bedside, and the use or not of ancillary tests. However, argumentative braindead cases have recently raised up new disputes, arguing up-to-date BD criteria by questioning accepted medical standards. ...
... [45] Hence, this author recently proposed to move from "whole brain criterion" to "brain as a whole criterion", to fulfil the "definition of death as the cessation of the organism as a whole". [1,3] The United States President's Commission for the Study of Ethical Problems in Medicine and Biomedical and Behavioral Research quoted Bernat and his colleagues' research to adopt the whole-brain formulation of death, [1,3,36,46,47] by all US states in the Uniform Determination of Death Act (UDDA). [48] McGee and Gardiner, [49] stated that the lawful basis for death declaration in the UK and Commonwealth countries, is fairly well settled, based on the medical standards provided by the Royal Colleges' Code of Practice, [50] mainly based on the Christopher Pallis' brainstem death view. ...
... [45] Hence, this author recently proposed to move from "whole brain criterion" to "brain as a whole criterion", to fulfil the "definition of death as the cessation of the organism as a whole". [1,3] The United States President's Commission for the Study of Ethical Problems in Medicine and Biomedical and Behavioral Research quoted Bernat and his colleagues' research to adopt the whole-brain formulation of death, [1,3,36,46,47] by all US states in the Uniform Determination of Death Act (UDDA). [48] McGee and Gardiner, [49] stated that the lawful basis for death declaration in the UK and Commonwealth countries, is fairly well settled, based on the medical standards provided by the Royal Colleges' Code of Practice, [50] mainly based on the Christopher Pallis' brainstem death view. ...
Background:
New controversies have raised on brain death (BD) diagnosis when lesions are localized in the posterior fossa.
Objective:
The aim of this study was to discuss the particularities of BD diagnosis in patients with posterior fossa lesions.
Materials and methods:
The author made a systematic review of literature on this topic.
Results and conclusions:
A supratentorial brain lesion usually produces a rostrocaudal transtentorial brain herniation, resulting in forebrain and brainstem loss of function. In secondary brain lesions (i.e., cerebral hypoxia), the brainstem is also affected like the forebrain. Nevertheless, some cases complaining posterior fossa lesions (i.e., basilar artery thrombotic infarcts, or hemorrhages of the brainstem and/or cerebellum) may retain intracranial blood flow and EEG activity. In this article, I discuss that if a posterior fossa lesion does not produce an enormous increment of intracranial pressure, a complete intracranial circulatory arrest does not occur, explaining the preservation of EEG activity, evoked potentials, and autonomic function. I also addressed Jahi McMath, who was declared braindead, but ancillary tests, performed 9 months after initial brain insult, showed conservation of intracranial structures, EEG activity, and autonomic reactivity to "Mother Talks" stimulus, rejecting the diagnosis of BD. Jahi McMath's MRI study demonstrated a huge lesion in the pons. Some authors have argued that in patients with primary brainstem lesions it might be possible to find in some cases partial recovery of consciousness, even fulfilling clinical BD criteria. This was the case in Jahi McMath.
... As the process of brain edema and cellular damage makes its way down the brainstem, a Cushing reflex often occurs, with profound bradycardia and hypertension, a result of pontine ischemia causing mixed sympathetic and vagal stimulation (Smith, 2004;Nakagawa and Tang, 2011;Bernat and Dalle Ave, 2019). This is followed by "catecholamine storm," as large amounts of the catecholamines epinephrine and norepinephrine are released, causing severe vasoconstriction, tachycardia, hypertension, and organ damage, including myocardial injury. ...
... This "storm" occurs because, normally, parasympathetic and sympathetic responses balance each other in a reciprocal inhibitory-excitatory fashion. However, when the parasympathetic vagal and cardiomotor nuclei of the medulla become ischemic, sympathetic activation is unopposed, thus releasing massive amounts of stimulating, sympathetic hormones, which can cause severe end-organ injury (Smith, 2004;Bernat and Dalle Ave, 2019). Finally, as the process reaches completion at the cervicomedullary junction, the upper cervical spinal cord also becomes injured (Schneider and Matakas, 1971;2 M. NAIR-COLLINS AND A.R. JOFFE Walker et al., 1975;Walker, 1980), finally resulting in profound hypotension from loss of vasomotor tone, and the rostral-caudal progression of injury is complete. ...
... Similarly, multiple international professional societies, known as "The World Brain Death Project," also acknowledged the possibility of a preserved neurohormonal function and stated, "It is recommended that persistence of hormonal regulatory functions does not preclude the diagnosis of [brain death]" (Greer et al., 2020). This is an area of ongoing debate in medical and scholarly literatures (Bernat and Dalle Ave, 2019;Miller, 2019, 2020). For the purpose of this chapter, we do not comment on this debate, instead of focusing on explaining why this may occur, along with the practical consequences of its occurrence. ...
Some patients who have been diagnosed as “dead by neurologic criteria” continue to exhibit certain brain functions, most commonly, neuroendocrine functions. In this chapter, we review the pathophysiology of brain death that can lead either to neuroendocrine failure or to preserved neuroendocrine functioning. We review the evidence on continued hypothalamic functioning in patients who have been declared “brain dead,” examine potential mechanisms that would explain these findings, and discuss how these findings create additional confounds for brain death testing. We conclude by reviewing the evidence for the management of hypothalamic–pituitary failure in the setting of brain death and organ transplantation.
... The Uniform Determination of Death Act (UDDA) or some variant of it is the statutory definition of death in all 50 states (President's Commission, 1981). There is an inconsistency, however, between it and official diagnostic protocols (Shewmon, 2018a;Bernat and Dalle Ave, 2019;Dalle Ave and Bernat, 2020), so that many instances of declared BD 1 do not fulfill the literal requirements of the law. The current reassessment of the UDDA by the Uniform Law Commission is therefore opportune and long overdue. ...
... Nevertheless, these patients have been diagnosed for decades as "BD," despite the glaring inconsistency with the UDDA (no doubt motivated by the great need for transplantable organs coupled with the perception of a hopeless prognosis). Additional kinds of discrepancy between the neurological criterion (UDDA) and the tests for death (the Guidelines) also exist (Shewmon, 2018a;Bernat and Dalle Ave, 2019;Dalle Ave and Bernat, 2020;Nair-Collins and Miller, 2020). ...
Discrepancies between the Uniform Determination of Death Act (UDDA) and the adult and pediatric diagnostic guidelines for brain death (BD) (the “Guidelines”) have motivated proposals to revise the UDDA. A revision proposed by Lewis, Bonnie and Pope (the RUDDA), has received particular attention, the three novelties of which would be: (1) to specify the Guidelines as the legally recognized “medical standard,” (2) to exclude hypothalamic function from the category of “brain function,” and (3) to authorize physicians to conduct an apnea test without consent and even over a proxy’s objection. One hundred seven experts in medicine, bioethics, philosophy, and law, spanning a wide variety of perspectives, have come together in agreement that while the UDDA needs revision, the RUDDA is not the way to do it. Specifically, (1) the Guidelines have a non-negligible risk of false-positive error, (2) hypothalamic function is more relevant to the organism as a whole than any brainstem reflex, and (3) the apnea test carries a risk of precipitating BD in a non-BD patient, provides no benefit to the patient, does not reliably accomplish its intended purpose, and is not even absolutely necessary for diagnosing BD according to the internal logic of the Guidelines; it should at the very least require informed consent, as do many procedures that are much more beneficial and less risky. Finally, objections to a neurologic criterion of death are not based only on religious belief or ignorance. People have a right to not have a concept of death that experts vigorously debate imposed upon them against their judgment and conscience; any revision of the UDDA should therefore contain an opt-out clause for those who accept only a circulatory-respiratory criterion.
... For example, in this Journal, Dalle Ave and Bernat have reviewed multiple cases of inconsistencies between the standardly accepted tests 2,3 -which do not assess all brain functions-and the physiological criterion of irreversible cessation of all functions of the entire brain, which is alleged to be identified by these tests. 4,5 Dalle Ave and Bernat 4 document cases of patients diagnosed as brain-dead who have preserved neurohormonal function, preserved oculocardiac reflex (a brainstem reflex), transient return of spontaneous breathing, persistence of electroencephalographic and evoked potential activity, and preserved intracranial blood flow. Furthermore, also in this Journal, Nair-Collins and colleagues reviewed studies encompassing over 1800 patients diagnosed as brain-dead and found that approximately half demonstrated evidence of preserved brain function in the form of hypothalamic osmoregulation, manifested by the absence of central diabetes insipidus. ...
... Apart from hypothalamic function, there are several well-documented cases of precisely what the AAN alleges not to exist: compliant application of the standard guidelines, followed by a return (transient or not), of spontaneous breathing, or brainstem reflexes. 4,5,13 Indeed, Shewmon recently reported just such a case of return of spontaneous ventilatory effort, and even included a checklist demonstrating that the diagnosis was made in compliance with the accepted guidelines. 14 Making false, and even logically impossible claims, does nothing to assist the AAN's members, nor the patients they serve; and indeed it deleteriously contributes to misinformation about brain death among clinicians and others. ...
The legal standard for the determination of death by neurologic criteria in the United States is laid out in the Uniform Determination of Death Act (UDDA), which requires the irreversible cessation of all functions of the entire brain. Most other nations endorse a “whole-brain” standard as well. However, current practice in the determination of death by neurologic criteria is not consistent with this legal standard, because some patients who are diagnosed as brain-dead, in fact retain some brain function, or retain the capacity for the return of some brain function. In response, the American Academy of Neurology published updated guidelines, which assert that hypothalamic function is consistent with the neurological standard enshrined in the UDDA. Others have suggested that it is an open question whether the hypothalamus and pituitary are part of “the entire brain,” as delineated in the UDDA. While we agree that determination of death practices are worthy of continued dialogue and refinement in practice that dialogue must adhere to reasonable standards of logic and scientific accuracy.
... However, these definitions differ between countries, and, for example, Canada and the United Kingdom require only irreversible cessation function in the brainstem, focusing on arousal and ability to sustain respiration. There has been ongoing debate concerning the diagnostic accuracy of current tests; although accuracy appears to be high, false positive diagnoses of BD do occur [83,84]. Whatever the initial insult, brainstem death seems to follow a common pathway with increases in intracranial pressure (ICP), and reducing cerebral circulation causing anoxic brain injury. ...
In the comatose patient, urgent diagnosis can be a critical priority if appropriate interventions are going to be performed promptly. In many cases, imaging investigations will form a core component of this assessment. In others, where clinical criteria allow confident diagnosis, imaging may still be of significant benefit in providing confirmatory information and may also provide clinically useful prognostic data. In the critically ill comatose patient, confirmation of a diagnosis of brain death may be required. Although this diagnosis is based on clinical criteria, imaging has long been used to provide adjunct supportive information. In recent years, there has been an increased interest in the use of imaging to support a diagnosis of brain death as functional imaging modalities have improved. In this chapter, we will initially review the role of imaging in supporting diagnosis and prognostication in patients suffering from coma. We will discuss the optimal imaging strategies, specific disorders, and specific imaging findings which might help with differential diagnosis and prognostication. We will then discuss the role of imaging in supporting the diagnosis of brain death.
... Uyuşmazlıkları azaltmak için önerdiği stratejiler, doktorlar için BD belirleme eğitiminin iyileştirilmesini, mutlaka beyin dolaşımının tam olarak ortadan kalktığını gösteren bir test yapılmasını veya tüm BD kriterlerinin gözden geçirilmesini içerir. 20 Bu öneriler ve yorum görüldüğü gibi aslında güncel "tüm BD" klinik tanısı ile fizyopatoloji arasındaki uyumsuzluğun kabulüdür. ...
... [63][64][65][66][67][68][69][70][71][72][73][74][75][76][77][78], dziś jednak przeważnie same historyczne i najczęściej w ujęciu przyczynkarskim [79][80][81][82][83][84][85][86][87][88][89][90][91]. Rzadko relatywnie publikowane są artykuły problem naświetlające w perspektywie bioetyki/filozofii medycyny [92][93][94][95][96][97][98][99][100][101][102][103]. Na początku wieku najliczniej na krajowym rynku wydawniczym pojawiały się prace eksponujące relację między umierającym pacjentem a otoczeniem społecznym, zwłaszcza opiekunami nieprofesjonalnymi [104][105][106][107][108][109][110][111][112][113][114][115][116][117][118]. ...
The aim of the master’s thesis was to research the health-related quality of life (HRQoL) of caregivers of relatives with end-stage cancer. The dramatic illness of a relative was considered a risk factor for physical and mental burdens. The problems of family members are underestimated in the literature.
The research was conducted from November, 2022 to April, 2023. The diagnostic survey method was used. Within it, the technique of a survey was used. The research tool, a survey questionnaire, compiled standardized tests: Edmonton Symptom Assessment Scale (ESAS), Hospital Anxiety and Depression Scale Modified (HADS-M) and Euro-Quality of Life Questionnaire (EQ-5D-5L).
The study showed 125 caregivers and family members of terminally ill cancer charges (w: 81.6%, N = 125; m: 18.4%, N = 125), mostly living in cities of 150-500 thousand inhabitants (80%, N = 125), most often (76.8%, N = 125) at the age of 50 or older, with dominant upper secondary education: general (after the equivalent of ‘comprehensive high school’)/technical (technological; in Poland, after ‘technikum’, that is, a type of formerly existed in the UK ‘secon-dary technical school’ or still functioning ‘technology college’ closest) (60.8%, N = 125). Usually (84.8%, N =125), the duration of care exceeded half a year. Spouses (27.2%, N =125) and in-laws (25.6%, N = 125) prevailed over other relatives. The charges aged 45 or older definitely dominated (84.8%, N = 125) over the younger ones. Nearly half (48%, N = 125) of the charges' primary cancer foci covered three locations: lung, large intestine, and breast (listed in descending order of frequency). The most metastases (85,(45)% of all metastases, N = 110) were in the brain, lung, and liver (listed in decreasing order of frequency). Only 4 (3.2%) charges were referred for palliative care without attempting causal treatment. Also, only in 4 charges physicians stopped at a therapeutic strategy involving solely radiotherapy. Among the combined therapies, the second most complex was dominant (a fusion of surgery, radiotherapy, and chemotherapy; 67.2%, N = 125). The caregivers that assessed charges’ pain, fatigue, nausea, depression, anxiety, drowsiness, appetite, well-being, and shortness of breath to be the worst were characterized by a statistically significant decrease in their own HRQoL
in terms of mobility (Spearman’s rank correlation coefficient ρ = 0.895, p-value = 0.001), self-service (ρ = 0.925 , p-value = 0.001), performing usual activities (ρ = 0.953, p = 0.001), and pain (ρ = 0.832, p-value = 0.001). The caregivers that assessed charges’ pain, fatigue, nausea, depression, anxiety, drowsiness, appetite, well-being, and shortness of breath to be the worst also showed a statistically significant increasing of their own depression/anxiety (ρ = 0.875, p-value = 0.001). In addition, the lower the caregiver's HRQoL, the greater the likelihood of developing mixed depressive and anxiety disorder (MDAD) (6A73 according International Statistical Classification of Diseases and Related Health Problems 11th Revision, ICD-11 or 309.28 (F43.23) according Diagnostic and Statistical Manual of Mental Disorders 5th Edition, DSM-5) (ρ = 0.901, p-value = 0.000).
A more severe course of the terminal phase of the charge's cancer is conducive to the occurrence of MDAD in family caregivers. A stricter assessment by the caregiver of the severity of the charge's symptoms also lowers the caregiver's self-assessment of HRQoL (ρ = 0.980, p = 0.000). Self-assessments of individual HRQoL ranges correlate with an indication on a numerical scale of 0-100 (for the sum of self-assessment results in the Kruskal-Wallis Test - H: H = 194.131, standard deviation SD = 4.47462, p-value = 0.01).
Celem badań była rekonstrukcja zależnej od zdrowia jakości życia (health-related quality of life, HRQoL) opiekunów krewnych w schyłkowej chorobie nowotworowej. Terminalną chorobę krewnego uznano za czynnik ryzyka obciążeń fizycznych i psychicznych. W literaturze nie docenia się problemów członków rodzin.
Badania prowadzono od listopada 2022 r. do kwietnia 2023 r. Wykorzystano metodę sondażu diagnostycznego. W jej obrębie posłużono się techniką ankiety. W narzędziu badawczym, kwestionariuszu ankiety, skompilowano standaryzowane testy: Edmonton Symptom Assessment Scale (ESAS), Hospital Anxiety and Depression Scale Modified (HADS-M) oraz Euro-Quality of Life Questionnaire (EQ-5D-5L).
Badania wykazały 125 opiekunów i członków rodzin pacjentów onkologicznych w stadium terminalnym (k: 81,6%, N = 125; m: 18,4%, N = 125), przeważnie mieszkających w miastach 150-500 tysięcy mieszkańców (n = 80%, N = 125), najczęściej (76,8%, N = 125) w wieku 50 lat i starszych, z dominującym wykształceniem średnim ogólnym/ technicznym bądź wyższym (n = 60,8%, N = 125). Zwykle (84.8%, N = 125) czas trwania opieki przekraczał pół roku. Małżonkowie (27,2%, N = 125) i powinowaci (25,6%, N = 125) przeważali nad pozostałymi krewnymi. Podopieczni w wieku 45 lat i starsi zdecydowanie dominowali (84,8%, N = 125) nad młodszymi. Blisko połowa (48%, N = 125) pierwotnych ognisk nowotworowych Podopiecznych obejmowała trzy lokalizacje: płuco, jelito grube i pierś (wymienione w kolejności malejącej częstości). Najwięcej przerzutów (85,(45)% przerzutów, N = 110) dotyczyło mózgu, płuca i wątroby (wymienione w kolejności malejącej częstości). Tylko u 4 (3,2%) Podopiecznych ograniczono się do leczenia objawowego. Także tylko u 4 Podopiecznych poprzestano na strategii terapeutycznej obejmującej wyłącznie radioterapię. Z terapii skojarzonych dominowała druga pod względem złożoności (leczenie chirurgiczne + radioterapia + chemioterapia; 67,2%, N = 125). Opiekunowie ból, zmęczenie, nudności, depresję, lęk, senność, apetyt, samopoczucie, duszność Podopiecznych oceniający jako najgorsze sami charakteryzowali się istotnym statystycznie obniżeniem własnej HRQoL w zakresie poruszania się (współczynnik korelacji rang Spearmana rS = 0,895, p-wartość = 0,001), samoobsługi
(rS = 0,925, p-wartość = 0,001), wykonywania zwykłych czynności (rS = 0,953, p-wartość = 0,001) oraz odczuwanego bólu (rS = 0,832, p-wartość = 0,001). Opiekunowie jako najgorsze oceniający ból, zmęczenie, nudności, depresję, lęk, senność, apetyt, samopoczucie, duszność Podopiecznych wykazywali się też statystycznie istotnym nasileniem własnego przygnębienia/niepokoju (rS = 0,875, p-wartość = 0,001). Poza tym niższa HRQoL opiekuna zwiększała ryzyko wystąpienia u niego mieszanego zaburzenia depresyjnego i lękowego (mixed anxiety and depressive disorder, MDAD) (6A74 według Międzynarodowej Statystycznej Klasyfikacji Chorób i Problemów Zdrowotnych, rewizji 11, ICD-11 lub 309.28 (F43.23) według piątego wydania klasyfikacji zaburzeń psychicznych Amerykańskiego Towarzystwa Psychiatrycznego, DSM-5) (rS = 0,901, p-wartość = 0,000).
Cięższy przebieg terminalnej fazy choroby nowotworowej Podopiecznego sprzyja występowaniu MDAD u opiekunów rodzinnych. Surowsza ocena przez opiekuna nasilenia objawów Podopiecznego obniża też samoocenę HRQoL opiekuna (rS = 0,980, p-wartość = 0,000). Samooceny poszczególnych zakresów HRQoL korelują ze wskazaniem na skali liczbowej 0-100 (dla sumy wyników samoocen w Teście Kruskala-Wallisa, H: H = 194,131, odchylenie standardowe SD = 4,47462, p-wartość = 0,01).
... others argue that BD/DNC guidelines should require cessation of every brain function, including hypothalamic neurosecretory function. 4,15 Antidiuretic hormone (ADH) is the most frequently discussed neurosecretory hormone in the context of BD/DNC, but the hypothalamus controls secretion of several other hormones including adrenocorticotropic hormone (ACTH), follicle-stimulating hormone (FSH), growth hormone (GH), luteinizing hormone (LH), oxytocin, prolactin, and thyroid-stimulating hormone (TSH). 16 A review of hypothalamic neurosecretory hormone levels at the time of BD/DNC determination demonstrated normal levels are common: ACTH (48% of 65 patients), ADH (50% of 2,546 patients), and TSH (78% of 347 patients). ...
The Uniform Determination of Death Act (UDDA) revision series in Neurology® originated in response to the Uniform Law Commission’s plan to create a revised Uniform Determination of Death Act (rUDDA) to address contemporary controversies associated with brain death/death by neurologic criteria (BD/DNC) determination. This article contextualizes these, and other, controversies and reviews the extent to which they represent potential threats and impediments to the clinical practice of BD/DNC determination. It also explains the reasons that our rapidly evolving understanding of the brain’s ability to recover from injury should not influence the clinical practice of BD/DNC determination. Finally, it explores the myriad ways in which the American Academy of Neurology has addressed potential threats and impediments to the clinical practice of BD/DNC determination and the implications potential changes to the UDDA may have on the future of the clinical practice of BD/DNC determination.
... 15 To align the law with practice, either the "accepted medical standards" must include a more demanding set of tests that exclude neurosecretory functioning or the text requiring cessation of "all functions of the entire brain" must be revised. 16,17 At some level, the criteria used to determine death must be a matter of convention and consensus. 18,19 The relevant question is not whether any brain functions remain, but, rather, whether those functions contradict a determination of death. ...
Although the Uniform Determination of Death Act (UDDA) has served as a model statute for 40 years, there is a growing recognition that the law must be updated. One issue being considered by the Uniform Law Commission’s Drafting Committee to revise the UDDA is whether the text “all functions of the entire brain, including the brainstem” should be changed. Some argue that the absence of diabetes insipidus indicates that some brain functioning continues in many individuals who otherwise meet the “accepted medical standards” like the American Academy of Neurology’s. The concern is that the legal criteria and the medical standards used to determine death by neurological criteria are not aligned. We argue for the revision of the UDDA to more accurately specify legal criteria which align with the medical standards: brain injury leading to permanent loss of a) the capacity for consciousness, b) the ability to breathe spontaneously, and c) brainstem reflexes. We term these criteria “neuro-respiratory criteria” and show that they are well-supported in the literature for physiological and social reasons justifying their use in the law.
... In addition, the origin of blood flow that must reach the intracranial contents seems irrelevant to the claimed pathophysiology of BD: this blood flow would be as restricted as intracranial blood flow from other sources (e.g., internal carotid arteries) by the presumed very high intracranial pressure. It is more likely that the hypothalamic function reflects an area of the brain more resistant to low intracranial blood flow than other parts of the brain [182]. ...
Brain death has been accepted worldwide medically and legally as the biological state of death of the organism. Nevertheless, the literature has described persistent problems with this acceptance ever since brain death was described. Many of these problems are not widely known or properly understood by much of the medical community. Here we aim to clarify these issues, based on the two intractable problems in the brain death debates. First, the metaphysical problem: there is no reason that withstands critical scrutiny to believe that BD is the state of biological death of the human organism. Second, the epistemic problem: there is no way currently to diagnose the state of BD, the irreversible loss of all brain functions, using clinical tests and ancillary tests, given potential confounders to testing. We discuss these problems and their main objections and conclude that these problems are intractable in that there has been no acceptable solution offered other than bare assertions of an ‘operational definition’ of death. We present possible ways to move forward that accept both the metaphysical problem - that BD is not biological death of the human organism - and the epistemic problem - that as currently diagnosed, BD is a devastating neurological state where recovery of sentience is very unlikely, but not a confirmed state of irreversible loss of all [critical] brain functions. We argue that the best solution is to abandon the dead donor rule, thus allowing vital organ donation from patients currently diagnosed as BD, assuming appropriate changes are made to the consent process and to laws about killing.
... If severe enough, this can result in brain herniation [15]. These physiologic derangements in the brain also have cascading and reciprocal effects on the rest of the organism, such as systemic inflammation which in turn can exacerbate brain injury; liver damage from coagulopathies can exacerbate brain injury via an accumulation of ammonia in the nervous system [10, p. 800-801]; "catecholamine storm" can occur, which involves unopposed release of massive amounts of sympathetic, stimulant hormones that cause tissue injury including to the myocardium [16,17]; dysfunction of hypothalamic areas results in multiple neuroendocrine derangements which also alter brain chemistry [13]; and so on. ...
A novel pulsatile-perfusion technology, dubbed Brain Ex , has been shown to restore microcirculation and cellular functions in the pig brain, 4 h postmortem. This technology has generated enthusiasm for its translational value for human neuroresuscitation. I offer a critical analysis of the study and its methodology, providing several reasons for skepticism. This includes: all phenomena were observed at different degrees of hypothermia; the physiological and biochemical milieu of the experimental preparation is radically different than the clinical setting of hypoxic-ischemic brain injury; and the study is confounded by uncontrolled traumatic brain injury and lifelong stress in all the animals.
... If the particular drug, or even the cause of coma are not known, but high suspicion persists, the patient should be observed for 48 hours to determine whether a change in brain stem reflexes occurs; if no change is observed, a test of cerebral blood supply should be performed (81)(82)(83) . ...
Object: The present study was designed to answer several concerns
disclosed by systematic reviews, indicating no evidence to support the use of
computed tomography angiography (CTA) in the diagnosis of brain death (BD).
Therefore, the aim of this study was to assess CTA for the diagnosis of BD
and to define the optimal tomographic criteria of intracranial circulatory arrest.
Methods: A unicenter prospective, observational case-control study was
undertaken. Comatose patients (Glasgow Coma Scale ≤ 5), even subjects
presenting with the first signs of BD, were included. CTA scanning of arterial
and venous vasculature and transcranial Doppler (TCD) were performed. A
neurological determination of BD and consequently determination of case (BD
group) or control (no-BD group) was conducted. All personnel involved with
assessing patients were blinded to further tests results. CTA accuracy was
calculated based on the criteria of bilateral no visualization of the internal
cerebral veins and the distal middle cerebral arteries, the 4-point score (4PS),
and an exclusive criterion of absence of deep brain venous drainage
exclusively, the venous score (VS), considering only the internal cerebral veins
bilaterally. Results: A total of 106 patients were enrolled in this study; 52
patients did not have BD, and none of these patients had circulatory arrest
observed by CTA or TCD (100% specificity). Of the 54 patients with a clinical
diagnosis of BD, 33 met the 4PS (61.1% sensitivity), whereas 47 met the VS
(87% sensitivity). The accuracy of CTA was time-related, with greater accuracy
when scanning was performed less than 12 hours prior to the neurological
assessment, reaching 95.5% sensitivity with the VS. Conclusions: CTA can
reliably support a diagnosis of BD. The criterion of absence of deep venous
opacification can confirm the occurrence of cerebral circulatory arrest.
... If the particular drug, or even the cause of coma are not known, but high suspicion persists, the patient should be observed for 48 hours to determine whether a change in brain stem reflexes occurs; if no change is observed, a test of cerebral blood supply should be performed (81)(82)(83) . ...
Computed tomography angiography accuracy on the brain death diagnosis.
A study designed to answer AAN concerns on the use of CTA to aid brain death determination.
... Finally, in cases whether drug abuse or the cause of coma is unclear, but in the absence of CNS depressors high BD suspicion persists, the patient should be observed for 48 hours to determine whether a change in brain stem reflexes occurs; if no change is observed, a test of cerebral blood supply should be performed before apnea test 52,53 . A circulatory arrest observed, plus neurological assessment (even better if performed more than once by different trained physicians) and apnea test also positive will indicate BD with no possibility of mistaken, to the date knowledge. ...
Objective: We present a case of coma with uncertain inception and brain death (BD) diagnosis misconducting. The definite diagnosis was Bickerstaff syndrome (brainstem encephalitis), with good recovery posterior to immunoglobulin therapy. Situations with potential to challenge coma evaluation are presented and the beneficial role of blood flow ancillary testing is discussed. Methods: Hospitalization report and online literature review. Discussion: Not only acceptance and understanding of death are fraught with variation worldwide, but even medical knowledge and training to perform BD assessment, especially when situations are not ordinary. Conclusion: Performing a blood flow examination prior to initiating BD clinical assessment in uncommon cases may be the best practice.
This chapter examines concepts and criteria of death and the coherence of their associations. Concepts of death fall into two broad categories: non-ontological and ontological. Non-ontological concepts include death as a cluster kind and death as a process; the corresponding criteria are stipulative, based on pragmatic concerns. Ontological concepts are essentially either psychological (cessation of “personhood,” equated with capacity for thinking and self-awareness) or biological (cessation of the human organism). The psychological concept corresponds to a “higher brain” criterion, namely irreversible, permanent nonfunction (destruction) of bilateral thalami (the sufficiency of neocortical destruction alone being uncertain); anatomically broader criteria are sufficient but not necessary. The biological concept corresponds to a criterion of irreversible, permanent cessation of circulation of oxygenated blood (irreversible cessation of brain function being necessary but not sufficient). Irreversible apneic unconsciousness is best understood not as a concept of death but as a stipulative criterion. Concepts of life and death and their corresponding criteria derive from fundamental worldviews, on which there has been no consensus for over two millennia, nor is there likely ever to be. Respect for deeply held fundamental worldviews requires allowance for personal specification of circulatory or brain-based criteria.
Debates and criticism surrounding death by neurologic criteria feed on knowledge gaps and unanswered questions. Performance of high-quality research is necessary to advance the scientific basis for practice while acknowledging that metaphysical and spiritual concerns are not answerable by scientific inquiry. Prospective research in patients with devastating brain injury during the dying process and after death is feasible, and there is a myriad of topics that warrant attention. This chapter strives to advance an international structured research agenda that will help improve the evidence base and inform the determination of death after devastating brain injury.
Irreversible loss of all functions of the entire brain must be confirmed in order to determine death by neurologic criteria (i.e. brain death). However, in many cases the accepted medical standards for determination of death by neurologic criteria cannot absolutely confirm either irreversibility or the loss of all functions of the entire brain. One way to reconcile this discrepancy is to require the absence of brain circulation to determine death by neurologic criteria. Prolonged absent brain circulation guarantees neuronal death, and is thus the only way to assure both irreversibility and loss of all functions of the entire brain. In this chapter, I discuss how the accepted medical standards for determination of death by neurologic criteria fail to determine death by neurologic criteria. I then discuss several benefits that will emerge if these accepted medical standards are amended to require the absence of brain circulation: (1) more accurate determination of loss of all functions of the entire brain, (2) more accurate determination of irreversibility, and (3) improved congruity with the determination of death by circulatory-respiratory criteria.
The whole-brain criterion for death requires the absence of all functions of the entire brain. It follows logically that the preservation of any function of any part of the brain is not consistent with the whole-brain criterion for death. The hypothalamus is a part of the brain and has been shown to continue functioning in up to 50% of patients declared dead by neurologic criteria. Therefore, up to 50% of patients declared dead under the whole-brain criterion for death are false-positive misdiagnoses. Numerous responses have been offered to explain why preserved hypothalamic function is consistent with the whole-brain criterion for death. All these responses fail.
The conceptual basis for the brain criterion of death is the permanent cessation of the human organism-as-a-whole. This holistic concept relies on principles of organized hierarchies, emergent functions, biological mereology, and self-integration as applied to brain functions. It grants that many parts of the human organism can remain alive by technological support despite the cessation of the organism-as-a-whole. This rationale, endorsed by scholars and two US ethics commissions, remains vague, relies on intuition, and needs a more detailed analysis. Cases of mismatch between the whole-brain criterion of death and the test battery accepted in the United States could be lessened by changing the whole-brain criterion of death to the brain-as-a-whole criterion. Although many physicians conceptualize brain death using the brain-as-a-whole criterion, it remains in an early developmental stage and needs reasoned accounts of which brain functions characterize the brain-as-a-whole and why. There is noncongruence between the biological concept of death as irreversible and the accepted medical practice of determining death at a time when the vital functions have ceased permanently but not irreversibly. This noncongruence has long been accepted by society but recently has triggered disputes over death determination in organ donors after the circulatory determination of death. The reality of the noncongruence should be recognized and laws should state the prevailing medical standard of permanent vital function cessation for death determination, irrespective of organ donation.
50 years after its introduction, brain death remains controversial among scholars. The debates focus on one question: is brain death a good criterion for determining death? This question has been answered from various perspectives: medical, metaphysical, ethical, and legal or political. Most authors either defend the criterion as it is, propose some minor or major revisions, or advocate abandoning it and finding better solutions to the problems that brain death was intended to solve when it was introduced. Here I plead for a different approach that has been overlooked in the literature: the philosophy of science approach. Some scholars claim that human death is a matter of fact, a biological phenomenon whose occurrence can be determined empirically, based on science. We should take this claim seriously, whether we agree with it or not. The question is: how do we know that human death is a scientific matter of fact? Taking the philosophy of science approach means, among other things, examining how the determination of human death became an object of scientific inquiry, exploring the nature of the brain death criterion itself, and analysing the meaning of its core concepts such as “irreversibility” and “functions”.
Fifty years after its introduction, brain death remains controversial among scholars. The debates focus on one question: is brain death a good criterion for determining death? This question has been answered from various perspectives: medical, metaphysical, ethical, and legal or political. Most authors either defend the criterion as it is, propose some minor or major revisions, or advocate abandoning it and finding better solutions to the problems that brain death was intended to solve when it was introduced. In short, debates about brain death have been characterized by partisanship, for or against. Here I plead for a non-partisan approach that has been overlooked in the literature: the epistemological or philosophy of science approach. Some scholars claim that human death is a matter of fact, a biological phenomenon whose occurrence can be determined empirically, based on science. We should take this claim seriously, whether we agree with it or not. Question is: how do we know that human death is a scientific matter of fact? Taking the epistemological approach means, among other things, examining how the determination of human death became an object of scientific inquiry, exploring the nature of the brain death criterion itself, and analysing the meaning of its core concepts such as “irreversibility” and “functions”.
Preprint available at F1000Research: https://doi.org/10.12688/f1000research.109184.1
Some patients who have been diagnosed as “dead by neurologic criteria” continue to exhibit certain brain functions, most commonly, neuroendocrine functions. This preservation of neurologic function after the diagnosis of “brain death” or “brainstem death” is an ongoing source of controversy and concern in the medical, bioethics, and legal literatures. Most obviously, if some brain function persists, then it is not the case that all functions of the entire brain have ceased and hence, declaring such a patient to be “dead” would be a false positive, in any nation with so-called “whole brain death” laws. Furthermore, and perhaps more concerning, the preservation of any brain function necessarily entails the preservation of some amount of brain perfusion, thereby raising the concern as to whether additional areas of neural tissue may remain viable, including areas in the brainstem. These and other considerations cast significant doubt on the reliability of diagnosing either “brain death” or “brainstem death.”
Drawing on a recent case report of a pregnant, brain‐dead woman who gave birth to a healthy child after over seven months of intensive care treatment, this essay rejects the established doctrine in medicine that brain death constitutes the biological death of the human being. The essay describes three policy options with respect to determination of death and vital organ transplantation in the case of patients who are irreversibly comatose but remain biologically alive.
Lewis et al.1 developed the largest and most complete assessment ever performed for identifying similarities and differences in protocols on determination of brain death/death by neurologic criteria (BD/DNC). The authors found substantial variability in protocols, which might partially explain why quarrelsome brain-dead cases have recently raised up new disputes on accepting BD.2,3 The presence of primary posterior fossa lesions enforces the needs of “aligning the criterion and tests for brain death.”4 In some patients fulfilling clinical BD criteria, when a posterior fossa lesion does not provoke an important increment of intracranial pressure, there may be not a full absence of cerebral blood flow, explaining preservation of EEG activity, evoked potentials, and autonomic function in some cases.3 Some authors commented that in the case of isolated brain-stem lesions, sparing the mesopontine tegmental reticular formation, this condition would theoretically lead to a fully apneic locked-in syndrome—which imitates brainstem death—with the possibility of retaining some degree of consciousness for some time, even fulfilling clinical BD criteria.5 This was the case in Jahi McMath.3 Further research and discussion are necessary concerning the use or not of ancillary tests in BD diagnosis, in the presence of primary posterior fossa lesions.
El término muerte cerebral se entiende como el cese irreversible de las funciones cerebrales incluidas las del tronco encefálico. El determinar el fallecimiento de una persona cuando todavía presenta signos vitales genera gran controversia con respecto al tema de donación de órganos y la fiabilidad del diagnóstico certero. Hasta este momento ninguna prueba de gabinete ha demostrado ser completamente adecuada y aunque son muchos las pruebas que se utilizan mundialmente, ninguna ha sido adoptada dentro de una guía oficial.
In this paper, I reviewed the case of Jahi McMath who was diagnosed as being in brain death (BD). Nonetheless, ancillary tests, performed 9 months after initial brain insult, showed conservation of intracranial structures, EEG activity, and autonomic reactivity to “Mother Talks” stimulus. She was clinically in a state of unarousable and unresponsiveness, without evidence of awareness of self or environment, but full absence of brainstem reflexes, and partial responsiveness rejected the possibility of being in coma. Jahi was not a UWS, because she was not in a wakefulness state, and showed partial responsiveness. LIS patients are wakeful and aware, and although these cases are quadriplegic, they fully or partially preserve brainstem reflexes, vertical eye movements, and/or blinking, and respire by their own, rejecting the possibility of classifying her as a LIS patient. She was not a MCS because she did not preserve arousal, and only partially preserved awareness. The CRS-R resulted in a very low score, not corresponding with MCS patients. MCS patients fully or partially preserve brainstem reflexes, and usually breathe by their own. MCS has been always described as a transitional state between coma, UWS, but MCS has never been reported in a patient who has all clinical BD findings. This case doesn’t contradict the concept of BD, but brings again to discussion the needs of using ancillary tests in BD. I concluded that Jahi represented a new state of disorder of consciousness, non-previously described, that I have termed: “responsive unawake syndrome” (RUS).
Commentary: Defining Death: Definitions, Criteria, and Tests - Volume 28 Special Issue - ROBERT D. TRUOG
Commentary: False Positives in the Diagnosis of Brain Death - Volume 28 Special Issue - MICHAEL NAIR-COLLINS, FRANKLIN G. MILLER
Death can be defined as the permanent cessation of the organism as a whole. Although the organism as a whole is a century-old concept, it remains better intuited than analyzed. Recent concepts in theoretical biology including hierarchies of organization, emergent functions, and mereology have informed the idea that the organism as a whole is the organism’s critical emergent functions. Because the brain conducts the critical emergent functions including conscious awareness and control of respiration and circulation, the cessation of brain functions is death of the organism. A newer concept, the brain as a whole, may offer a superior criterion of death to the whole-brain criterion, because it more closely matches accepted clinical brain death tests and confirms the cessation of the organism’s emergent functions. Although the concepts of organism as a whole and brain as a whole remain vague and in need of rigorous biophilosophical analysis, their future precision will be restricted by the categorical limitations intrinsic to theoretical biological models.
Although death statutes permitting physicians to declare brain death are relatively uniform throughout the United States, academic debate persists over the equivalency of human death and brain death. Alan Shewmon showed that the formerly accepted integration rationale was conceptually incomplete by showing that brain-dead patients demonstrated a degree of integration. We provide a more complete rationale for the equivalency of human death and brain death by defending a deeper understanding of the organism as a whole (OaaW) and by using a novel strategy with shared objectives to justify death determination criteria. Our OaaW account describes different types of OaaW, defining human death as the loss of status as a human OaaW. We defend human death as similar to nonhuman death in terms of wakefulness, but also distinct in terms of the sui generis properties, particularly conscious awareness. We thereby defend the equivalency of brain death and human death using a resulting neurocentric rationale.
Brain death has been accepted as a legal definition of death in most countries, but practices for determining brain death vary widely. One source of variation is in the use of ancillary tests to assist in the diagnosis of brain death. Through case-based discussions with 3 experts from 3 continents, this article discusses selected aspects of brain death, with a focus on the use of ancillary tests. In particular, we explore the following questions: Are ancillary tests necessary, or is the clinical examination sufficient? What ancillary tests are preferred, and under which circumstances? Are ancillary tests required when the primary mechanism of injury is brainstem injury? Should the family's wishes play a role in the need for ancillary tests? The same case-based questions were posed to the rest of our readership in an online survey, the preliminary results of which are also presented.
The concept of death and its relationship to organ transplantation continue to be a source of debate and confusion among academics, clinicians, and the public. Recently, an international group of scholars and clinicians, in collaboration with the World Health Organization, met in the first phase of an effort to develop international guidelines for determination of death. The goal of this first phase was to focus on the biology of death and the dying process while bracketing legal, ethical, cultural, and religious perspectives. The next phase of the project will include a broader group of stakeholders in the development of clinical practice guidelines and will use expert consensus on biomedical criteria for death from the first phase as scientific input into normative deliberation about appropriate policies and practices.
This issue’s “Legal Briefing” column covers recent legal developments involving total brain failure. Death determined by neurological criteria (DDNC) or “brain death” has been legally established for decades in the United States. But recent conflicts between families and hospitals have created some uncertainty. Clinicians are increasingly unsure about the scope of their legal and ethical treatment duties when families object to the withdrawal of physiological support after DDNC. This issue of JCE includes a thorough analysis of one institution’s ethics consults illustrating this uncertainty. This experience is not unique. Hospitals across the country are seeing more DDNC disputes. Because of the similarity to medical futility disputes, some court cases on this topic were reviewed in a prior “Legal Briefing” column. But a more systematic review is now warranted. I categorize recent legal developments into the following nine categories:
1. History of Determining Death by Neurological Criteria
2. Legal Status of Determining Death by Neurological Criteria
3. Legal Duties to Accommodate Family Objections
4. Protocols for Determining Death by Neurological Criteria
5. Court Cases Seeking Physiological Support after DDNC
6. Court Cases Seeking Damages for Intentionally Premature DDNC
7. Court Cases Seeking Damages for Negligently Premature DDNC
8. Court Cases Seeking Damages for Emotional Distress
9. Pregnancy Limitations on DDNC
In order to find out the function of the hypothalamo-pituitary axis in brain dead patients, pituitary and hypothalamic hormone concentrations were measured and several anterior pituitary releasing tests were carried out in 39 brain dead patients. In addition, cerebral blood flow measurements were simultaneously performed. In almost all cases, the blood concentration of pituitary and hypothalamic hormones were above the sensitivity of the assay. Anterior pituitary releasing tests indicated that efficient functions of the hypothalamus were severely suppressed, while the normal secretory mechanism of the anterior pituitary was partially preserved in brain dead patients. Histological changes of hypothalamic neurons varied from barely detectable ghost cells to nearly normal cells even in the same case. Although, the remaining circulation seemed not to be sufficient enough to maintain integrated hypothalamo-pituitary function, as shown by the examinations of cerebral blood flow, the presence of hypothalamic hormones in the systemic circulation suggests that these hormones were released and carried from the hypothalamus by minimal flow which is preserved even after the diagnosis of brain death.
The data reviewed here suggest the possibility that a global reduction of blood supply to the whole brain or solely to the infratentorial structures down to the range of ischemic penumbra for several hours or a few days may lead to misdiagnosis of irreversible brain or brain stem damage in a subset of deeply comatose patients with cephalic areflexia. The following proposals are advanced: 1) the lack of any set of clinically detectable brain functions does not provide a safe diagnosis of brain or brain stem death; 2) apnea testing may induce irreversible brain damage and should be abandoned; 3) moderate hypothermia, antipyresis, prevention of arterial hypotension, and occasionally intra-arterial thrombolysis may contribute to good recovery of a possibly large subset of cases of brain injury currently regarded as irreversible; 4) confirmatory tests for brain death should not replace or delay the administration of potentially effective therapeutic measures; 5) in order to validate confirmatory tests, further research is needed to relate their results to specific levels of blood supply to the brain. The current criteria for the diagnosis of brain death should be revised.
This article clarifies some issues raised by Dr. Ariane Lewis in her recent “Current Opinion/Arguments” article on the case of Jahi McMath. Review of case materials. Jahi’s case most likely represents an instance of global ischemic penumbra (GIP) mimicking brain death (BD), with intracranial blood flow too low to support neuronal function or to be detected by radionuclide scan but sufficient to prevent widespread necrosis. Her MRI scan 9 months after the ischemic insult showed gross preservation of cortical and internal structures, incompatible with there ever having been a period of completely absent blood flow. Regarding Jahi’s alleged intermittent responsiveness, the set of videos, unsystematic as they are, constitutes convincing evidence that her movements in seeming response to command are not of spinal cord origin and are indeed voluntary responses, placing her in the category of minimally conscious state (MCS). In the absence of serial examinations by experts in MCS, the benefit of the doubt should be given. Unfortunately, her death on June 22, 2018, 4½ years after the diagnosis of BD, precludes such examinations. During those 4½ years, Jahi underwent menarche, with three documented menstrual periods, and ongoing pubertal development. Her case is an important example of false-positive diagnosis of BD, demonstrating the inability of current diagnostic standards to distinguish true BD from potentially reversible brain nonfunction due to GIP. The incidence of such mimicry is impossible to determine, because in most cases a BD diagnosis becomes a self-fulfilling prophecy.
Background:
The case of Jahi McMath has captured the attention of the public, healthcare professionals, and ethicists. Jahi was declared brain dead in late 2013, but her family transferred her to New Jersey to continue organ support. A lengthy legal battle has been ongoing since then. Jahi's family and two neurologists, Drs. Calixto Machado and Alan Shewmon, believe that she is not brain dead. Her family and Dr. Shewmon think that she is capable of following commands, thus making her minimally conscious.
Methods:
Review of case materials.
Results and conclusion:
Because brain death is an irreversible coma, one of three conclusions must be drawn: 1) Jahi was never dead; 2) Jahi met the criteria for brain death, but she isn't dead now; or 3) Jahi's movements are not purposeful responses, and she has been brain dead since 2013. The possibility that a person who was declared brain dead is now following commands threatens to erode the notion that brain death should be considered legal death. The discordant ideas that Jahi is brain dead and is following commands can only be reconciled if a formal evaluation for determination of death is repeated by reputable examiners.
To assess the practices and perceptions of brain death determination worldwide and analyze the extent and nature of variations among countries.
An electronic survey was distributed globally to physicians with expertise in neurocritical care, neurology, or related disciplines who would encounter patients at risk of brain death.
Most countries (n = 91, response rate 76%) reported a legal provision (n = 63, 70%) and an institutional protocol (n = 70, 77%) for brain death. Institutional protocols were less common in lower-income countries (2/9 of low [22%], 9/18 lower-middle [50%], 22/26 upper-middle [85%], and 37/38 high-income countries [97%], p < 0.001). Countries with an organized transplant network were more likely to have a brain death provision compared with countries without one (53/64 [83%] vs 6/25 [24%], p < 0.001). Among institutions with a formalized brain death protocol, marked variability occurred in requisite examination findings (n = 37, 53% of respondents deviated from the American Academy of Neurology criteria), apnea testing, necessity and type of ancillary testing (most commonly required test: EEG [n = 37, 53%]), time to declaration, number and qualifications of physicians present, and criteria in children (distinct pediatric criteria: n = 38, 56%).
Substantial differences in perceptions and practices of brain death exist worldwide. The identification of discrepancies, improvement of gaps in medical education, and formalization of protocols in lower-income countries provide first pragmatic steps to reconciling these variations. Whether a harmonized, uniform standard for brain death worldwide can be achieved remains questionable.
© 2015 American Academy of Neurology.
The publicity surrounding the recent McMath and Muñoz cases has rekindled public interest in brain death: the familiar term for human death determination by showing the irreversible cessation of clinical brain functions. The concept of brain death was developed decades ago to permit withdrawal of therapy in hopeless cases and to permit organ donation. It has become widely established medical practice, and laws permit it in all U.S. jurisdictions. Brain death has a biophilosophical justification as a standard for determining human death but remains poorly understood by the public and by health professionals. The current controversies over brain death are largely restricted to the academy, but some practitioners express ambivalence over whether brain death is equivalent to human death. Brain death remains an accepted and sound concept, but more work is necessary to establish its biophilosophical justification and to educate health professionals and the public.
We seek to change the conversation about brain death by highlighting the distinction between brain death as a biological concept versus brain death as a legal status. The fact that brain death does not cohere with any biologically plausible definition of death has been known for decades. Nevertheless, this fact has not threatened the acceptance of brain death as a legal status that permits individuals to be treated as if they are dead. The similarities between "legally dead" and "legally blind" demonstrate how we may legitimately choose bright-line legal definitions that do not cohere with biological reality. Not only does this distinction bring conceptual coherence to the conversation about brain death, but it has practical implications as well. Once brain death is recognized as a social construction not grounded in biological reality, we create the possibility of changing the social construction in ways that may better serve both organ donors and recipients alike.
To review and revise the 1987 pediatric brain death guidelines.
Relevant literature was reviewed. Recommendations were developed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system.
1) Determination of brain death in term newborns, infants, and children is a clinical diagnosis based on the absence of neurologic function with a known irreversible cause of coma. Because of insufficient data in the literature, recommendations for preterm infants <37 wks gestational age are not included in this guideline. 2) Hypotension, hypothermia, and metabolic disturbances should be treated and corrected and medications that can interfere with the neurologic examination and apnea testing should be discontinued allowing for adequate clearance before proceeding with these evaluations. 3) Two examinations, including apnea testing with each examination separated by an observation period, are required. Examinations should be performed by different attending physicians. Apnea testing may be performed by the same physician. An observation period of 24 hrs for term newborns (37 wks gestational age) to 30 days of age and 12 hrs for infants and children (>30 days to 18 yrs) is recommended. The first examination determines the child has met the accepted neurologic examination criteria for brain death. The second examination confirms brain death based on an unchanged and irreversible condition. Assessment of neurologic function after cardiopulmonary resuscitation or other severe acute brain injuries should be deferred for ≥24 hrs if there are concerns or inconsistencies in the examination. 4) Apnea testing to support the diagnosis of brain death must be performed safely and requires documentation of an arterial Paco2 20 mm Hg above the baseline and ≥60 mm Hg with no respiratory effort during the testing period. If the apnea test cannot be safely completed, an ancillary study should be performed. 5) Ancillary studies (electroencephalogram and radionuclide cerebral blood flow) are not required to establish brain death and are not a substitute for the neurologic examination. Ancillary studies may be used to assist the clinician in making the diagnosis of brain death a) when components of the examination or apnea testing cannot be completed safely as a result of the underlying medical condition of the patient; b) if there is uncertainty about the results of the neurologic examination; c) if a medication effect may be present; or d) to reduce the interexamination observation period. When ancillary studies are used, a second clinical examination and apnea test should be performed and components that can be completed must remain consistent with brain death. In this instance, the observation interval may be shortened and the second neurologic examination and apnea test (or all components that are able to be completed safely) can be performed at any time thereafter. 6) Death is declared when these criteria are fulfilled.
To describe a patient with transient reversal of findings of brain death after cardiopulmonary arrest and attempted therapeutic hypothermia.
Case report.
Intensive care unit of an academic tertiary care hospital.
A 55-yr-old man presented with cardiac arrest preceded by respiratory arrest. Cardiopulmonary resuscitation was performed, spontaneous perfusion restored, and therapeutic hypothermia was attempted for neural protection. After rewarming to 36.5°C, neurologic examination showed no eye opening or response to pain, spontaneous myoclonic movements, sluggishly reactive pupils, absent corneal reflexes, and intact gag and spontaneous respirations. Over 24 hrs, remaining cranial nerve function was lost. The neurologic examination was consistent with brain death. Apnea test and repeat clinical examination after a duration of 6 hrs confirmed brain death. Death was pronounced and the family consented to organ donation. Twenty-four hrs after brain death pronouncement, on arrival to the operating room for organ procurement, the patient was found to have regained corneal reflexes, cough reflex, and spontaneous respirations. The care team faced the challenge of offering an adequate explanation to the patient's family and other healthcare professionals involved.
Induced hypothermia and brain death determination.
This represents the first published report in an adult patient of reversal of a diagnosis of brain death made in full adherence to American Academy of Neurology guidelines. Although the reversal was transient and did not impact the patient's prognosis, it impacted his eligibility for organ donation and cast doubt about the ability to determine irreversibility of brain death findings in patients treated with hypothermia after cardiac arrest.
We strongly recommend caution in the determination of brain death after cardiac arrest when induced hypothermia is used. Confirmatory testing should be considered and a minimum observation period after rewarming before brain death testing ensues should be established.
To provide an update of the 1995 American Academy of Neurology guideline with regard to the following questions: Are there patients who fulfill the clinical criteria of brain death who recover neurologic function? What is an adequate observation period to ensure that cessation of neurologic function is permanent? Are complex motor movements that falsely suggest retained brain function sometimes observed in brain death? What is the comparative safety of techniques for determining apnea? Are there new ancillary tests that accurately identify patients with brain death?
A systematic literature search was conducted and included a review of MEDLINE and EMBASE from January 1996 to May 2009. Studies were limited to adults.
In adults, there are no published reports of recovery of neurologic function after a diagnosis of brain death using the criteria reviewed in the 1995 American Academy of Neurology practice parameter. Complex-spontaneous motor movements and false-positive triggering of the ventilator may occur in patients who are brain dead. There is insufficient evidence to determine the minimally acceptable observation period to ensure that neurologic functions have ceased irreversibly. Apneic oxygenation diffusion to determine apnea is safe, but there is insufficient evidence to determine the comparative safety of techniques used for apnea testing. There is insufficient evidence to determine if newer ancillary tests accurately confirm the cessation of function of the entire brain.
Since the establishment of the concept of declaring death by brain criteria, a large extent of variability in the determination of brain death has been reported. There are no standardized practical guidelines, and major differences exist in the requirements for the declaration of brain death throughout the USA and internationally. The American Academy of Neurology published evidence-based practice parameters for the determination of brain death in adults in 1995, requiring the irreversible absence of clinical brain function with the cardinal features of coma, absent brainstem reflexes, and apnea, as well as the exclusion of reversible confounders. Ancillary tests are recommended in cases of uncertainty of the clinical diagnosis. Every step in the determination of brain death bears potential pitfalls which can lead to errors in the diagnosis of brain death. These pitfalls are presented here, and possible solutions identified. Suggestions are made for improvement in the standardization of the declaration of brain death.
Brain death is the irreversible lost of function of the brain including the brainstem. The presence of spontaneous or reflex movements constitutes a challenge for the neurological determination of death. We reviewed historical aspects and practical implications of the presence of spontaneous or reflex movements in individuals with brain death and postulated pathophysiological mechanisms. We identified and reviewed 131 articles on movements in individuals with confirmed diagnosis of brain death using Medline from January 1960 until December 2007, using 'brain death' or 'cerebral death' and 'movements' or 'spinal reflex' as search terms. There was no previous systematic review of the literature on this topic. Plantar withdrawal responses, muscle stretch reflexes, abdominal contractions, Lazarus's sign, respiratory-like movements, among others were described. For the most part, these movements have been considered to be spinal reflexes. These movements are present in as many as 40-50% of heart-beating cadavers. Although limited information is available on the determinants and pathophysiological mechanisms of spinal reflexes, clinicians and health care providers should be aware of them and that they do not preclude the diagnosis of brain death or organ transplantation.
Fifty-six consecutive patients clinically diagnosed as brain dead were seen at Loyola University Medical Center, Maywood, Ill, from January 1984 through May 1986. Eleven (19.6%) of the 56 patients had electroencephalographic (EEG) activity following the diagnosis of brain death. The mean duration of the observed EEG activity was 36.6 hours (range, two to 168 hours). Three patterns of EEG activity were observed: (1) low-voltage (4 to 20 microV) theta or beta activity was recorded in nine (16.1%) patients as long as 72 hours following brain death. Neuropathologic studies in one patient showed hypoxic-ischemic neuronal changes involving all cell layers of the cerebral cortex, basal ganglia, brain stem, and cerebellum; (2) sleep-like activity (a mixture of synchronous 30 to 40 microV theta and delta activity and 60 to 80 microV, 10 to 12 Hz spindle-like potentials) was noted in two (3.6%) patients for as long as 168 hours following brain death. Pathologic studies in both cases demonstrated ischemic necrosis of the brain stem with relative preservation of the cerebral cortex; and (3) alpha-like activity (monotonous, unreactive, anteriorly predominant, 25 to 40 microV, 9 to 12 Hz activity) was observed in one (1.8%) patient three hours following brain death. Regardless of activity on the EEG, none of the patients recovered. The occurrence of EEG activity following brain death would suggest reliance on the EEG to confirm brain death may be unwarranted. The use of the EEG as a confirmatory test of brain death may be of questionable value.
Modern technology has raised questions about the definition of death, and various factors that influence public policy about declaring people dead. The widely accepted "whole-brain" definition of death is inadequate and should be replaced by a definition of "irreversible loss of consciousness and cognition." Any definition that identifies the innate ability of the organism to "integrate" itself or function "as a whole" should be rejected. The proponents of such definitions fail to provide a standard for the selection of essential sub-systems. The innate integration of vegetative functions cannot be used as the necessary and sufficient condition for life. A person without innate integration can still be alive; a dead person retaining just this function can survive as a living, mindless organism. Only cognitive functions have a spontaneity that is, in principle, irreplaceable.
Brain death has been discussed extensively for the last 25 years. Most investigators now believe that requiring death of the entire brain as the criterion for brain death in the Uniform Determination of Death Act and the standard clinical tests of brain death outlined in the Report of the Medical Consultants to the President's Commission have produced a satisfactory resolution of the issues surrounding the determination of death. However, we show that satisfying the standard medical tests does not guarantee that all brain functions have actually ceased and that there is tension between the legal criterion and the standard clinical tests. After considering and rejecting six possible reconciliations, we present an alternative approach that does not acknowledge any sharp dichotomy between life and death and incorporates the proposition that the questions of when care can be unilaterally discontinued, when organs can be harvested, and when a patient is ready for the services of an undertaker should be answered independent of any single account of death.
No one really believes that literally all functions of the entire brain must be lost for an individual to be dead. A better definition of death involves a higher brain orientation.
The vegetative state and the minimally conscious state are disorders of consciousness that can be acute and reversible or chronic and irreversible. Diffuse lesions of the thalami, cortical neurons, or the white-matter tracts that connect them cause the vegetative state, which is wakefulness without awareness. Functional imaging with PET and functional MRI shows activation of primary cortical areas with stimulation, but not of secondary areas or distributed neural networks that would indicate awareness. Vegetative state has a poor prognosis for recovery of awareness when present for more than a year in traumatic cases and for 3 months in non-traumatic cases. Patients in minimally conscious state are poorly responsive to stimuli, but show intermittent awareness behaviours. Indeed, findings of preliminary functional imaging studies suggest that some patients could have substantially intact awareness. The outcomes of minimally conscious state are variable. Stimulation treatments have been disappointing in vegetative state but occasionally improve minimally conscious state. Treatment decisions for patients in vegetative state or minimally conscious state should follow established ethical and legal principles and accepted practice guidelines of professional medical specialty societies.
Google ScholarPubMed The authors grouped the cases into several categories: (1) obvious clinical brain functions that were disregarded in the test batteries; (2) cases in which brain functions may have been present
- A L Ave
- J L Bernat