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1.
Neurology ; 102(6): e209196, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38408293

RESUMO

When the Uniform Law Commission (ULC) was recently in the process of revising the Uniform Determination of Death Act (UDDA), Neurology® ran a series of debates over certain controversial issues being deliberated. Omitted was a debate over the fundamental concept underlying brain death. In his introductory article, Bernat offered reasons for this omission: "It is not directly relevant to practicing neurologists who largely accept brain death, do not question its conceptual basis, …." In this article I argue the opposite: the fundamental concept of death is highly relevant to the clinical criteria and tests used to diagnose it. Moreover, most neurologists in fact disagree with the conceptual basis articulated by Bernat. Basically, there are 3 competing concepts of death: (1) biological: cessation of the integrative unity of the organism as a whole (endorsed by Bernat and the 1981 President's Commission), (2) psychological: cessation of the person, equated with a self-conscious mind (endorsed by half of neurologists), and (3) the vital work concept proposed by the 2008 President's Council on Bioethics. The first actually corresponds to a circulatory, not a neurologic, criterion. The second corresponds to a "higher brain" criterion. The third corresponds loosely to the UK's "brainstem death" criterion. In terms of the biological concept, current diagnostic guidelines entail a high rate of false-positive declarations of death, whereas in terms of the psychological concept, the same guidelines entail a high rate of false-negative declarations. Brainstem reflexes have nothing to do with any death concept (their role is putatively to guarantee irreversibility). By shining a spotlight on the deficiencies of the UDDA through attempting to revise it, the ULC may have unwittingly opened a Pandora's box of fresh scrutiny of the concept of death underlying the neurologic criterion-particularly on the part of state legislatures with irreconcilably opposed worldviews.


Assuntos
Bioética , Morte Encefálica , Humanos , Morte Encefálica/diagnóstico , Encéfalo , Tronco Encefálico
2.
J Neuropathol Exp Neurol ; 82(1): 6-20, 2022 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-36519406

RESUMO

Brain death (death by neurologic criteria) is declared in 2% of all in-hospital deaths in the United States. Published neuropathology studies of individuals maintained on cardiorespiratory support are generally decades old, and notably include only 3 cases with long intervals between brain and "somatic" death (68 days, 101 days, 20 years). Here, we share our observations in a young woman supported for nearly 4½ years following declaration of brain death after oropharyngeal surgery. While limited by tissue availability and condition, we found evidence of at least partial perfusion of the superficial cerebral and cerebellar cortices by external carotid and vertebral arteries (via meningeal and posterior pharyngeal branches), characterized by focal cellular reaction and organization. Dural venous sinuses had thrombosis and recanalization, as well as iron deposition. In nonperfused brain areas, tissue "mummification," akin to that seen in certain postmortem conditions, including macerated stillbirths and saponification (adipocere formation), was identified, and are reviewed herein. Unfortunately, correlation with years-earlier clinical and radiographic observations was not possible. Nevertheless, we feel that our careful neuropathologic inspection of this case expands the understanding of the spectrum of human brain tissue alterations possible in a very rarely seen set of conditions.


Assuntos
Morte Encefálica , Encéfalo , Feminino , Humanos , Estados Unidos , Morte Encefálica/patologia , Encéfalo/patologia
4.
Chest ; 161(5): 1147-1148, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35526889
5.
J Child Neurol ; 37(1): 35-42, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34814769

RESUMO

Jahi McMath was diagnosed brain dead on 12/12/2013 in strict accordance with both the pediatric and adult Guidelines, reinforced by 4 isoelectric electroencephalograms and a radionuclide scan showing intracranial circulatory arrest. Her magnetic resonance imaging scan 9 1/2 months later surprisingly showed gross integrity of cortex, basal ganglia, thalamus, and upper brainstem. The greatest damage was in the white matter, which was extensively demyelinated and cystic, and in the lower brainstem, most likely from partial herniation that resolved. The apparent integrity of gray matter and the ascending reticular activating system may have provided a potential structural basis for the reemergence of some limited brain functions, while the white matter and lower brainstem lesions would have caused severe motor disability, brainstem areflexia and apnea. The findings indicate that there could never have been a period of sustained intracranial circulatory arrest. Rather, at the time of brain death diagnosis, low blood flow below the detection threshold of the radionuclide scan was sufficient to maintain widespread neuronal viability, though insufficient to support synaptic function. Her case represents the first indirect confirmation of the reality and clinical relevance of global ischemic penumbra, hypothesized in 1999 as a generally unacknowledged and possibly common brain death mimic.


Assuntos
Morte Encefálica/diagnóstico , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Hipóxia-Isquemia Encefálica/patologia , Imageamento por Ressonância Magnética/métodos , Adolescente , Feminino , Humanos
6.
Perspect Biol Med ; 64(4): 457-478, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34840151

RESUMO

Jahi McMath was a 13-year-old girl who was declared brain dead on December 12, 2013, after a hemorrhagic complication following complex oropharyngeal surgery. Her case gained international attention as her mother fought a legal battle to keep her on life support. Upon issuance of a death certificate shortly after the declaration of brain death, Jahi was transferred from California to New Jersey, where the law includes a religious exemption from the neurologic determination of death. There she became statutorily resurrected and was treated as a comatose, living patient for the next four and a half years. During that time, she underwent menarche and other aspects of puberty and developed intermittent responsiveness to commands, documented by eyewitness attestations and multiple home videos. Jahi died on June 18, 2018, from abdominal complications. This article summarizes her clinical history over those intervening years, taken directly from her medical records and personal observation. Her case represents an instance of a false-positive diagnosis of brain death, unquestionably made according to both the pediatric and adult guidelines, reinforced by four false-positive EEGs and a false-positive radionuclide blood flow test. The bioethical consequences of a nonnegligible risk of false-positive declaration of death are profound.


Assuntos
Morte Encefálica , Mães , Adolescente , Criança , Feminino , Humanos
7.
J Med Philos ; 2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-33987668

RESUMO

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.

8.
Hastings Cent Rep ; 48 Suppl 4: S74-S76, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30584850

RESUMO

From the start, I followed the case of Jahi McMath with great interest. In December 2013, she clearly fulfilled the diagnostic criteria for brain death. As a neurologist with a special interest in chronic brain death, I was not surprised that, after she was flown to New Jersey, where she became statutorily resurrected and was treated as a comatose patient, Jahi's condition quickly improved. In 2014, her family reported that she sometimes responded to simple motor commands. I shared the general skepticism regarding these reports, assuming that the family was in denial and was misinterpreting spinal myoclonus (a rapid, involuntary twitch generated by the spinal cord) as volitional. The family had noticed that when Jahi's heart rate was above eighty beats per minute, she was more likely to respond, as though the heart rate reflected some sort of inner level of arousal. So they began to make video recordings. I have been privileged to be entrusted with copies of these recordings, forty-eight of which proved suitable for assessing alleged responsiveness. All have been certified by a forensic video expert as unaltered. The first thing that struck me was that the great majority of the alleged responses were not spinal myoclonus. In fact, they did not resemble any type of spontaneous, involuntary movement described in patients paralyzed from high spinal cord lesions.


Assuntos
Atitude do Pessoal de Saúde , Morte Encefálica , Morte , Erros de Diagnóstico , Cuidados para Prolongar a Vida , Morte Encefálica/diagnóstico , Morte Encefálica/fisiopatologia , Estado de Consciência/fisiologia , Erros de Diagnóstico/ética , Erros de Diagnóstico/psicologia , Técnicas de Diagnóstico Neurológico , Feminino , Humanos , Cuidados para Prolongar a Vida/ética , Cuidados para Prolongar a Vida/métodos , Cuidados para Prolongar a Vida/psicologia
9.
Hastings Cent Rep ; 48 Suppl 4: S22-S25, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30584860

RESUMO

At its inception, "brain death" was proposed not as a coherent concept but as a useful one. The 1968 Ad Hoc Committee of the Harvard Medical School to Examine the Definition of Brain Death gave no reason that "irreversible coma" should be death itself, but simply asserted that the time had come for it to be declared so. Subsequent writings by chairman Henry Beecher made clear that, to him at least, death was essentially a social construct, and society could define it however it pleased. The first widely endorsed attempt at a philosophical justification appeared thirteen years later, with a report from the President's Commission for the Study of Ethical Problems in Medicine and Biomedical and Behavioral Research and a seminal paper by James Bernat, Charles Culver, and Bernard Gert, which introduced the insightful tripartite scheme of concept, criterion, and tests for death. Their paper proposed that the correct concept of death is the "permanent cessation of functioning of the organism as a whole," which tenuously remains the mainstream concept to this day. In this essay, I focus on this mainstream concept, arguing that equating brain death with death involves several levels of incoherence: between concept and criterion, between criterion and tests, between tests and concept, and between all of these and actual brain death praxis.


Assuntos
Morte Encefálica , Morte , Temas Bioéticos , Dissidências e Disputas , Saúde Holística/tendências , Humanos , Cuidados para Prolongar a Vida/ética , Cuidados para Prolongar a Vida/psicologia , Percepção Social
10.
Neurocrit Care ; 29(2): 165-170, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30112685

RESUMO

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.


Assuntos
Morte Encefálica , Estado Vegetativo Persistente , Feminino , Humanos
11.
J Child Neurol ; 32(14): 1104-1117, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29129151

RESUMO

A 2-year-old boy with severe head trauma was diagnosed brain dead according to the 2011 Pediatric Guidelines. Computed tomographic (CT) scan showed massive cerebral edema with herniation. Intracranial pressures were extremely high, with cerebral perfusion pressures around 0 for several hours. An apnea test was initially contraindicated; later, one had to be terminated due to oxygen desaturation when the Pco2 had risen to 57.9 mm Hg. An electroencephalogram (EEG) was probably isoelectric but formally interpreted as equivocal. Tc-99m diethylene-triamine-pentaacetate (DTPA) scintigraphy showed no intracranial blood flow, so brain death was declared. Parents declined organ donation. A few minutes after withdrawal of support, the boy began to breathe spontaneously, so the ventilator was immediately reconnected and the death declaration rescinded. Two hours later, life support was again removed, this time for prognostic reasons; he did not breathe, and death was declared on circulatory-respiratory grounds. Implications regarding the specificity of the guidelines are discussed.


Assuntos
Morte Encefálica/diagnóstico por imagem , Erros de Diagnóstico , Circulação Cerebrovascular/fisiologia , Pré-Escolar , Eletroencefalografia , Reações Falso-Positivas , Humanos , Pressão Intracraniana , Masculino , Ácido Pentético/metabolismo , Cintilografia , Fatores de Tempo , Tomografia Computadorizada por Raios X
15.
J Med Philos ; 35(3): 256-98, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20439358

RESUMO

In debates about criteria for human death, several camps have emerged, the main two focusing on either loss of the "organism as a whole" (the mainstream view) or loss of consciousness or "personhood." Controversies also rage over the proper definition of "irreversible" in criteria for death. The situation is reminiscent of the proverbial blind men palpating an elephant; each describes the creature according to the part he can touch. Similarly, each camp grasps some aspect of the complex reality of death. The personhood camp, in contrast to the mainstream "organism" camp, recognizes that a human organism can still be a biological living whole even without brain function. The mainstream camp, in contrast to the personhood camp, recognizes that a person can be permanently, even irreversibly unconscious, and still be a living person so long as his/her body is alive. The author proposes that hylomorphic dualism incorporates both these key insights. But to complete the picture of the entire "death elephant," a fundamental paradigm shift is needed to make sense of other seemingly conflicting insights. The author proposes a "semantic bisection" of the concept of death, analogous to the traditional distinction at the beginning of life between "conception" and "birth." To avoid the semantic baggage associated with the term "death," the two new death-related concepts are referred to as "passing away" (or "deceased") and "deanimation," corresponding, respectively, to sociolegal ceasing-to-be (mirror image of birth) and ontological/theological ceasing-to-be of the bodily organism (mirror image of conception). Regarding criteria, the distinguishing feature is whether the cessation of function is permanent (passing away) or irreversible (deanimation). If the "dead donor rule" were renamed the "deceased donor rule" (both acronyms felicitously being "DDR"), the ethics of organ transplantation from non-heart-beating donors could, in principle, be validly governed by the DDR, even though the donors are not yet ontologically "deanimated." Thus, the paradigm shift satisfies both those who insist on maintaining the DDR and those who claim that it has all along been receiving only lip service and should be explicitly loosened to include those who are "as good as dead." Even so, a number of practical caveats remain to be worked out for non-heart-beating protocols.


Assuntos
Temas Bioéticos , Morte Encefálica/diagnóstico , Morte , Doadores de Tecidos , Animais , Atitude Frente a Morte , Encéfalo/fisiologia , Decapitação , Humanos , Pessoalidade , Inconsciência
16.
J Child Neurol ; 25(6): 732-7, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19794104

RESUMO

A 17-year-old male presented with sudden onset of persistent focal neurological symptoms. Magnetic resonance imaging (MRI) demonstrated a nonenhancing white matter lesion that appeared hyperintense on fluid-attenuated inversion recovery sequence and diffusion-weighted imaging, while hypointense on apparent diffusion coefficient mapping corresponding to the patient's clinical features. A smaller subclinical lesion was also present. The patient's history, radiographic findings, and initial hospital course including response to treatment appeared supportive of a stroke diagnosis. However, a rapid recovery from his severe neurological deficits and results of subsequent serologic testing strongly indicated a demyelinating condition. The onset of adolescent multiple sclerosis can present diagnostic and therapeutic challenges, especially when the initial demyelinating event resembles an acute stroke in clinical and radiographic presentation. Every effort should be made to distinguish these diagnoses as early as possible to ensure timely and appropriate management.


Assuntos
Isquemia Encefálica/diagnóstico , Encéfalo/patologia , Esclerose Múltipla/diagnóstico , Acidente Vascular Cerebral/diagnóstico , Adolescente , Mapeamento Encefálico , Diagnóstico Diferencial , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Fibras Nervosas Mielinizadas/patologia , Exame Neurológico
17.
Issues Law Med ; 25(1): 3-14, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19746819

RESUMO

Why is a patient with a destroyed brain considered dead rather than moribund and irreversibly comatose? The world has been grappling with this question for the past four decades with little success. The recently released white paper of the President's Council on Bioethics is in many respects a refreshing, thoughtful, and comprehensive reexamination of this complex topic. It offers a very helpful analysis of the major positions on the determination of death, and it proffers a creative new solution of its own. Unfortunately, the new solution does not put the problem to rest, but the humility with which the council discusses its own position and the honesty with which it confronts the consequences of being wrong alone make this report a very commendable document.


Assuntos
Morte Encefálica/legislação & jurisprudência , Temas Bioéticos , Humanos
19.
Kennedy Inst Ethics J ; 14(3): 277-300, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15497227

RESUMO

American society traditionally has assumed a univocal notion of "death," largely because we have only one word for it and, until recently, have not needed a more nuanced notion. The reality of death-processes does not preclude the reality of death events. Linguistically, "death" can be understood only as an event; there are other words for the process. Our death vocabulary should expand to reflect multiple events along the process from sickness to decomposition. Depending on context, some death-related events may constitute a more obvious discontinuity than others and more justifiably may be considered "death" within that context. There is no reason to assume a priori that there must be an overarching, unitary concept of death from which all diagnostic criteria must derive. Regarding organ transplantation, the relevant question is not "Is the patient dead?" but rather "Can organs X, Y, Z ... be removed without causing or hastening death or harming the patient?"


Assuntos
Morte , Doadores Vivos , Doente Terminal , Terminologia como Assunto , Doadores de Tecidos , Coleta de Tecidos e Órgãos/ética , Obtenção de Tecidos e Órgãos/ética , Inconsciência , Vocabulário , Animais , Atitude Frente a Morte , Morte Encefálica , Princípio do Duplo Efeito , Família , Parada Cardíaca , Homicídio/ética , Humanos , Opinião Pública , Política Pública , Ressuscitação , Consentimento do Representante Legal , Ventiladores Mecânicos
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