Functional neuroimaging and withdrawal of life-sustaining treatment from vegetative patients

Medical AI, inductive risk and the communication of uncertainty: the case of disorders of consciousness

Some patients, following brain injury, do not outwardly respond to spoken commands, yet show patterns of brain activity that indicate responsiveness. This is 'cognitive-motor dissociation' (CMD). Recent research has used machine learning to diagnose CMD from electroencephalogram recordings. These techniques have high false discovery rates, raising a serious problem of inductive risk. It is no solution to communicate the false discovery rates directly to the patient's family, because this information may confuse, alarm and mislead. Instead, we need a procedure for generating case-specific probabilistic assessments that can be communicated clearly. This article constructs a possible procedure with three key elements: (1) A shift from categorical 'responding or not' assessments to degrees of evidence; (2) The use of patient-centred priors to convert degrees of evidence to probabilistic assessments; and (3) The use of standardised probability yardsticks to convey those assessments as clearly as possible.

Valuing life and evaluating suffering in infants with life-limiting illness

In this paper, we explore three separate questions that are relevant to assessing the prudential value of life in infants with severe life-limiting illness. First, what is the value or disvalue of a short life? Is it in the interests of a child to save her life if she will nevertheless die in infancy or very early childhood? Second, how does profound cognitive impairment affect the balance of positives and negatives in a child's future life? Third, if the life of a child with life-limiting illness is prolonged, how much suffering will she experience and can any of it be alleviated? Is there a risk that negative experiences for such a child (suffering) will remain despite the provision of palliative care? We argue that both the subjective and objective components of well-being for children could be greatly reduced if they are anticipated to have a short life that is affected by profound cognitive impairment. This does not mean that their overall well-being will be negative, but rather that there may be a higher risk of negative overall well-being if they are expected to experience pain, discomfort, or distress. Furthermore, we point to some of the practical limitations of therapies aimed at relieving suffering, such that there is a risk that suffering will go partially or completely unrelieved. Taken together, these considerations imply that some life-prolonging treatments are not in the best interests of infants with severe life-limiting illness.

Applied potential of task-free event-related paradigms for assessing neurocognitive functions in disorders of consciousness

Diagnosing patients with disorders of consciousness is immensely difficult and often results in misdiagnoses, which can have fatal consequences. Despite the severity of this well-known issue, a reliable assessment tool has not yet been developed and implemented in the clinic. The main aim of this focused review is to evaluate the various event-related potential paradigms, recorded using EEG, which may be used to improve the assessment of patients with disorders of consciousness; we also provide a brief comparison of these paradigms with other measures. Notably, most event-related potential studies on the topic have focused on testing a small set of components, or even just a single component. However, to be of practical use, we argue that an assessment should probe a range of cognitive and linguistic functions at once. We suggest a novel approach that combines a set of well-tested auditory event-related potential components: N100, mismatch negativity, P3a, N400, early left anterior negativity and lexical response enhancement. Combining these components in a single, task-free design will provide a multidimensional assessment of cognitive and linguistic processes, which may help physicians make a more precise diagnosis.

It is never lawful or ethical to withdraw life-sustaining treatment from patients with prolonged disorders of consciousness

In English law there is a strong (though rebuttable) presumption that life should be maintained. This article contends that this presumption means that it is always unlawful to withdraw life-sustaining treatment from patients in permanent vegetative state (PVS) and minimally conscious state (MCS), and that the reasons for this being the correct legal analysis mean also that such withdrawal will always be ethically unacceptable. There are two reasons for this conclusion. First, the medical uncertainties inherent in the definition and diagnosis of PVS/MCS are such that, as a matter of medical fact, it can never be established, with the degree of certainty necessary to rebut the presumption, that it is not in the patient's best interest to remain alive. And second (and more controversially and repercussively), that even if permanent unconsciousness can be unequivocally demonstrated, the presumption is not rebutted. This is because there is plainly more to human existence than consciousness (or consciousness the markers of which can ever be demonstrated by medical investigations). It can never be said that the identity of the patient whose best interests are at stake evaporates (so eliminating the legal or ethical subject) when that person ceases to be conscious. Nor can it be said that the best interests of an unconscious person do not mandate continued biological existence. We simply cannot know. That uncertainty is legally conclusive, and (subject to resource allocation questions and views about the relevance of family wishes and the previously expressed wishes of the patient) should be ethically conclusive.

Do New Neuroimaging Findings Challenge the Ethical Basis of Advance Directives in Disorders of Consciousness?

Some authors have questioned the moral authority of advance directives (ADs) in cases in which it is not clear if the author of the AD is identical to the person to whom it later applies. This article focuses on the question of whether the latest results of neuroimaging studies have moral significance with regard to the moral authority of ADs in patients with disorders of consciousness (DOCs). Some neuroimaging findings could provide novel insights into the question of whether patients with DOCs exhibit sufficient psychological continuity to be ascribed diachronic personal identity. If those studies were to indicate that psychological continuity is present, they could justify the moral authority of ADs in patients with DOCs. This holds at least if respect for self-determination is considered as the foundation for the moral authority of ADs. The non-identity thesis in DOCs could no longer be applied, in line with clinical and social practice.

Correlation between neurobehavioural assessment and functional magnetic resonance imaging in the diagnosis of prolonged disorders of consciousness

The misdiagnosis rate of prolonged disorders of consciousness remains at approximately 40%, owing to overlap between diagnostic criteria and inconsistencies in patient responses. Improved accuracy is essential for the appropriate provision of treatment and rehabilitation. Neuroimaging may provide additional diagnostic information to standard neurobehavioural assessment, enabling identification of higher levels of awareness. In this study, the Sensory Tool to Assess Responsiveness (STAR) neurobehavioural assessment was used to assess the level of awareness of 19 patients with prolonged disorders of consciousness. Patients also completed an fMRI diagnostic assessment. The degree of concordance between fMRI and STAR diagnoses was substantial, despite significant delays for some patients between the two assessments. Discrepant diagnoses may relate to this delay or to the inconsistency of responses which characterise the minimally conscious state. The findings indicate that fMRI neuroimaging and STAR neurobehavioural assessment, while largely concordant, may identify different facets of awareness in some patients, which supports the use of both types of assessment in forming a diagnosis. Recommendations for future research include minimal delays between neurobehavioural and neuroimaging assessment, larger patient cohorts, and the use of multiple shorter fMRI assessments which provide more opportunities for patients to exhibit relevant behaviours.

Online public reactions to fMRI communication with patients with disorders of consciousness: Quality of life, end-of-life decision making, and concerns with misdiagnosis

BACKGROUND

Recently, the news media have reported on the discovery of covert awareness and the establishment of limited communication using a functional magnetic resonance imaging (fMRI) neuroimaging technique with several brain-injured patients thought to have been in a vegetative state. This discovery has raised many ethical, legal, and social questions related to quality of life, end-of-life decision making, diagnostic and prognostic accuracy in disorders of consciousness, resource allocation, and other issues. This project inquires into the public responses to these discoveries.

METHODS

We conducted a thematic analysis of online comments (n = 779) posted in response to 15 news articles and blog posts regarding the case of a Canadian patient diagnosed for 12 years as in a vegetative state, but who was reported in 2012 as having been able to communicate via fMRI. The online comments were coded using an iteratively refined codebook structured around 14 main themes.

RESULTS

Among the most frequent public reactions revealed in the online comments were discussions of the quality of life of patients with disorders of consciousness, whether life-sustaining treatment should be withdrawn (and whether the fMRI communication technique should be used to ask patients about this), and misgivings about the accuracy of diagnosis in disorders of consciousness and brain death.

CONCLUSIONS

These public perspectives are relevant to the obligations of clinicians, lawyers, and public policymakers to patients, families, and the public. Future work should consider how best to alleviate families' concerns as this type of research shakes their faith in diagnostic accuracy, to clarify the legal rules relating to advance directives in this context, and to address the manner in which public messaging might help to alleviate any indirect impact on confidence in the organ donation system.

Canadian perspectives on the clinical actionability of neuroimaging in disorders of consciousness

BACKGROUND

Acquired brain injury is a critical public health and socioeconomic problem in Canada, leaving many patients in vegetative, minimally conscious, or locked-in states, unresponsive and unable to communicate. Recent advances in neuroimaging research have demonstrated residual consciousness in a few exemplary patients with acquired brain injury, suggesting potential misdiagnosis and changes in prognosis. Such progress, in parallel with research using multimodal brain imaging technologies in recent years, has promising implications for clinical translation, notwithstanding the many challenges that impact health care and policy development. This study explored the perspectives of Canadian professionals with expertise either in neuroimaging research, disorders of consciousness, or both, on the potential clinical applications and implications of imaging technology.

METHODS

Twenty-two professionals from designated communities of neuroimaging researchers, ethicists, lawyers, and practitioners participated in semistructured interviews. Data were analyzed for emergent themes.

RESULTS

The five most dominant themes were: (1) validation and calibration of the methods; (2) informed consent; (3) burdens on the health care system; (4) implications for the Canadian health care system; and (5) possibilities for improved prognosis.

CONCLUSIONS

Movement of neuroimaging from research into clinical care for acquired brain injury will require careful consideration of legal and ethical issues alongside research reliability, responsible distribution of health care resources, and the interaction of technological capabilities with patient outcome.

EEG and fMRI agree: Mental arithmetic is the easiest form of imagery to detect

fMRI and EEG during mental imagery provide alternative methods of detecting awareness in patients with disorders of consciousness (DOC) without reliance on behaviour. Because using fMRI in patients with DOC is difficult, studies increasingly employ EEG. However, there has been no verification that these modalities provide converging information at the individual subject level. The present study examined simultaneous EEG and fMRI in healthy volunteers during six mental imagery tasks to determine whether one mental imagery task generates more robust activation across subjects; whether activation can be predicted from familiarity with the imagined activity; and whether EEG and fMRI converge upon the same conclusions about individual imagery performance. Mental arithmetic generated the most robust activation in the majority of subjects for both EEG and fMRI, and level of activation could not be predicted from familiarity, with either modality. We conclude that overall, EEG and fMRI agree regarding individual mental imagery performance.

Ethical and Clinical Considerations at the Intersection of Functional Neuroimaging and Disorders of Consciousness

Recent neuroimaging research on disorders of consciousness provides direct evidence of covert consciousness otherwise not detected clinically in a subset of severely brain-injured patients. These findings have motivated strategic development of binary communication paradigms, from which researchers interpret voluntary modulations in brain activity to glean information about patients' residual cognitive functions and emotions. The discovery of such responsiveness raises ethical and legal issues concerning the exercise of autonomy and capacity for decisionmaking on matters such as healthcare, involvement in research, and end of life. These advances have generated demands for access to the technology against a complex background of continued scientific advancement, questions about just allocation of healthcare resources, and unresolved legal issues. Interviews with professionals whose work is relevant to patients with disorders of consciousness reveal priorities concerning further basic research, legal and policy issues, and clinical considerations.

Relative Values: Perspectives on a Neuroimaging Technology From Above and Within the Ethical Landscape

In this paper we contribute to "sociology in bioethics" and help clarify the range of ways sociological work can contribute to ethics scholarship. We do this using a case study of an innovative neurotechnology, functional magnetic resonance imaging, and its use to attempt to diagnose and communicate with severely brain-injured patients. We compare empirical data from interviews with relatives of patients who have a severe brain injury with perspectives from mainstream bioethics scholars. We use the notion of an "ethical landscape" as an analogy for the different ethical positions subjects can take-whereby a person's position relative to the landscape makes a difference to the way they experience and interact with it. We show that, in comparison to studying abstract ethics "from above" the ethical landscape, which involves universal generalizations and global judgements, studying ethics empirically "from the ground," within the ethical landscape foregrounds a more plural and differentiated picture. We argue it is important not to treat empirical ethics as secondary to abstract ethics, to treat on-the-ground perspectives as useful only insofar as they can inform ethics from above. Rather, empirical perspectives can illuminate the plural vantage points in ethical judgments, highlight the "lived" nature of ethical reasoning, and point to all ethical vantage points as being significant. This is of epistemic importance to normative ethics, since researchers who pay attention to the various positions in and trajectories through the ethical landscape are unlikely to think about ethics in terms of abstract agency-as can happen with top-down ethics-or to elide agency with the agency of policymakers. Moreover, empirical perspectives may have transformative implications for people on the ground, especially where focus on the potential harms and benefits they face brings their experiences and interests to the forefront of ethical and policy discussion.

Ethical Issues in Neuroprognostication after Severe Pediatric Brain Injury

Neurologic outcome prediction, or neuroprognostication, after severe brain injury in children is a challenging task and has many ethical dimensions. Neurologists and intensivists are frequently asked by families to predict functional recovery after brain injury to help guide medical decision making despite limited outcome data. Using two clinical cases of children with severe brain injury from different mechanisms: hypoxic-ischemic injury secondary to cardiac arrest and traumatic brain injury, this article first addresses the importance of making a correct diagnosis in a child with a disorder of consciousness and then discusses some of the clinical challenges with deducing an accurate and timely outcome prediction. We further explore the ethical obligations of physicians when supporting parental decision making. We highlight the need to focus on how to elicit family values for a brain injured child, how to manage prognostic uncertainty, and how to effectively communicate with families in these challenging situations. We offer guidance for physicians when they have diverging views from families on aggressiveness of care or feel pressured to prognosticate with in a "window of opportunity" for limiting or withdrawing life sustaining therapies. We conclude with a discussion of the potential influence of emerging technologies, specifically advanced functional neuroimaging, on neurologic outcome prediction after severe brain injury.

Should patients in a persistent vegetative state be allowed to die? Guidelines for a new standard of care in Australian hospitals

In this article we will be arguing in favour of legislating to protect doctors who bring about the deaths of PVS patients, regardless of whether the death is through passive means (e.g. the discontinuation of artificial feeding and respiration) or active means (e.g. through the administration of pharmaceuticals known to hasten death in end-of-life care). We will first discuss the ethical dilemmas doctors and lawmakers faced in the more famous PVS cases arising in the US and UK, before exploring what the law should be regarding such patients, particularly in Australia. We will continue by arguing in favour of allowing euthanasia in the interests of PVS patients, their families, and finally the wider community, before concluding with some suggestions for how these ethical arguments could be transformed into a set of guidelines for medical practice in this area.

Ethics of neuroimaging after serious brain injury

BACKGROUND

Patient outcome after serious brain injury is highly variable. Following a period of coma, some patients recover while others progress into a vegetative state (unresponsive wakefulness syndrome) or minimally conscious state. In both cases, assessment is difficult and misdiagnosis may be as high as 43%. Recent advances in neuroimaging suggest a solution. Both functional magnetic resonance imaging and electroencephalography have been used to detect residual cognitive function in vegetative and minimally conscious patients. Neuroimaging may improve diagnosis and prognostication. These techniques are beginning to be applied to comatose patients soon after injury. Evidence of preserved cognitive function may predict recovery, and this information would help families and health providers. Complex ethical issues arise due to the vulnerability of patients and families, difficulties interpreting negative results, restriction of communication to "yes" or "no" answers, and cost. We seek to investigate ethical issues in the use of neuroimaging in behaviorally nonresponsive patients who have suffered serious brain injury. The objectives of this research are to: (1) create an approach to capacity assessment using neuroimaging; (2) develop an ethics of welfare framework to guide considerations of quality of life; (3) explore the impact of neuroimaging on families; and, (4) analyze the ethics of the use of neuroimaging in comatose patients.

METHODS/DESIGN

Our research program encompasses four projects and uses a mixed methods approach. Project 1 asks whether decision making capacity can be assessed in behaviorally nonresponsive patients. We will specify cognitive functions required for capacity and detail their assessment. Further, we will develop and pilot a series of scenarios and questions suitable for assessing capacity. Project 2 examines the ethics of welfare as a guide for neuroimaging. It grounds an obligation to explore patients' interests, and we explore conceptual issues in the development of a quality of life instrument adapted for neuroimaging. Project 3 will use grounded theory interviews to document families' understanding of the patient's condition, expectations of neuroimaging, and the impact of the results of neuroimaging. Project 4 will provide an ethical analysis of neuroimaging to investigate residual cognitive function in comatose patients within days of serious brain injury.

Attitudes of Lay People to Withdrawal of Treatment in Brain Damaged Patients

BACKGROUND

Whether patients in the vegetative state (VS), minimally conscious state (MCS) or the clinically related locked-in syndrome (LIS) should be kept alive is a matter of intense controversy. This study aimed to examine the moral attitudes of lay people to these questions, and the values and other factors that underlie these attitudes.

METHOD

One hundred ninety-nine US residents completed a survey using the online platform Mechanical Turk, comprising demographic questions, agreement with treatment withdrawal from each of the conditions, agreement with a series of ethical principles and three personality tests.

RESULTS

More supported treatment withdrawal from VS (40.2 % agreed, 17.6 % disagreed) than MCS (20.6 %, 41.2 %) or LIS (25.3 %, 35.8 %). Agreement with treatment withdrawal was negatively correlated with religiosity (r = -0.272, P < 0.001), though showed no significant relationship with need for cognition or empathy, and only a partial association with utilitarian judgment in a standard moral dilemma. Support for treatment withdrawal was most strongly associated with endorsement of the importance of patient autonomy, dignity, suffering, best interests. Distributive justice was not given significant weight by most. Importantly, agreement with treatment withdrawal was noticeably higher when considered from a first as opposed to third person perspective for VS (Z = -6.056, P < 0.001), MCS (Z = -6.746, P < 0.001) and LIS (Z = -6.681, P < 0.001).

CONCLUSION

Lay attitudes to withdrawal of treatment in brain damaged patients are largely shaped by values similar to those central to the secular ethical debate. Neither traditional values such as the sanctity of life nor utilitarian values relating to resource allocation seem to play a central role. Far greater weight is given to autonomy, which may explain why participants were far more willing to endorse withdrawal of treatment when the issue was presented in the first person, or in relation to a concrete case involving a patient's explicit wishes. Surveys focusing on abstract cases presented in the third person may not provide an accurate picture of lay attitudes to these critical ethical questions.

Disorders of consciousness: responding to requests for novel diagnostic and therapeutic interventions

Severe brain injury can leave patients with chronic disorders of consciousness. Because of impaired responsiveness, many of these patients have traditionally been regarded as unaware. However, findings from recent clinical studies herald a potential paradigm shift: functional imaging and neurophysiological studies have identified ways to assess awareness and have revealed astounding cases of awareness despite clinical unresponsiveness. Hence, diagnostic classifications have been rewritten, prognostic knowledge is improving, and therapeutic studies have regained momentum, showing for the first time some therapeutic effects on responsiveness. Clinicians must increasingly respond to requests by patients' families and surrogate decision makers to use novel techniques for diagnosis, prognosis, and treatment, and in doing so several ethical and social issues need to be considered. Such requests provide an opportunity for clinicians to learn about patients' values and preferences and to maintain clinical acumen for changes in patient status with the patients' best interests in mind.

Should we provide life-sustaining treatments to patients with permanent loss of cognitive capacities?

A very troubling issue for health care systems today is that of life-sustaining treatment for patients who have permanently lost their cognitive capacities. These include patients in persistent vegetative state (PVS), or minimally conscious state (MCS), as well as a growing population of patients at the very end stage of dementia. These patients are totally dependent on life-sustaining treatments and are, actually, kept alive "artificially." This phenomenon raises doubts as to the ethics of sustaining the life of patients who have lost their consciousness and cognitive capacities, and whether there is a moral obligation to do so. The problem is that the main facts concerning the experiences and well-being of such patients and their wishes are unknown. Hence the framework of the four principles-beneficence, non-maleficence, autonomy, and justice-is not applicable in these cases; therefore we examined solidarity as another moral value to which we may resort in dealing with this dilemma. This article shows that the source of the dilemma is the social attitudes towards loss of cognitive capacities, and the perception of this state as loss of personhood. Consequently, it is suggested that the principle of solidarity-which both sets an obligation to care for the worst-off, and can be used to identify obligations that appeal to an ethos of behavior-can serve as a guiding principle for resolving the dilemma. The value of solidarity can lead society to care for these patients and not deny them basic care and life-sustaining treatment when appropriate.

How family caregivers' medical and moral assumptions influence decision making for patients in the vegetative state: a qualitative interview study

BACKGROUND

Decisions on limiting life-sustaining treatment for patients in the vegetative state (VS) are emotionally and morally challenging. In Germany, doctors have to discuss, together with the legal surrogate (often a family member), whether the proposed treatment is in accordance with the patient's will. However, it is unknown whether family members of the patient in the VS actually base their decisions on the patient's wishes.

OBJECTIVE

To examine the role of advance directives, orally expressed wishes, or the presumed will of patients in a VS for family caregivers' decisions on life-sustaining treatment.

METHODS AND SAMPLE

A qualitative interview study with 14 next of kin of patients in a VS in a long-term care setting was conducted; 13 participants were the patient's legal surrogates. Interviews were analysed according to qualitative content analysis.

RESULTS

The majority of family caregivers said that they were aware of aforementioned wishes of the patient that could be applied to the VS condition, but did not base their decisions primarily on these wishes. They gave three reasons for this: (a) the expectation of clinical improvement, (b) the caregivers' definition of life-sustaining treatments and (c) the moral obligation not to harm the patient. If the patient's wishes were not known or not revealed, the caregivers interpreted a will to live into the patient's survival and non-verbal behaviour.

CONCLUSIONS

Whether or not prior treatment wishes of patients in a VS are respected depends on their applicability, and also on the medical assumptions and moral attitudes of the surrogates. We recommend repeated communication, support for the caregivers and advance care planning.

Diagnostic and ethical challenges in disorders of consciousness and locked-in syndrome: a survey of German neurologists

Diagnosis and decisions on life-sustaining treatment (LST) in disorders of consciousness, such as the vegetative state (VS) and the minimally conscious state (MCS), are challenging for neurologists. The locked-in syndrome (LiS) is sometimes confounded with these disorders by less experienced physicians. We aimed to investigate (1) the application of diagnostic knowledge, (2) attitudes concerning limitations of LST, and (3) further challenging aspects in the care of patients. A vignette-based online survey with a randomized presentation of a VS, MCS, or LiS case scenario was conducted among members of the German Society for Neurology. A sample of 503 neurologists participated (response rate 16.4%). An accurate diagnosis was given by 86% of the participants. The LiS case was diagnosed more accurately (94%) than the VS case (79%) and the MCS case (87%, p < 0.001). Limiting LST for the patient was considered by 92, 91, and 84% of the participants who accurately diagnosed the VS, LiS, and MCS case (p = 0.09). Overall, most participants agreed with limiting cardiopulmonary resuscitation; a minority considered limiting artificial nutrition and hydration. Neurologists regarded the estimation of the prognosis and determination of the patients’ wishes as most challenging. The majority of German neurologists accurately applied the diagnostic categories VS, MCS, and LiS to case vignettes. Their attitudes were mostly in favor of limiting life-sustaining treatment and slightly differed for MCS as compared to VS and LiS. Attitudes toward LST strongly differed according to circumstances (e.g., patient’s will opposed treatment) and treatment measures.

Should we allow organ donation euthanasia? Alternatives for maximizing the number and quality of organs for transplantation

There are not enough solid organs available to meet the needs of patients with organ failure. Thousands of patients every year die on the waiting lists for transplantation. Yet there is one currently available, underutilized, potential source of organs. Many patients die in intensive care following withdrawal of life-sustaining treatment whose organs could be used to save the lives of others. At present the majority of these organs go to waste. In this paper we consider and evaluate a range of ways to improve the number and quality of organs available from this group of patients. Changes to consent arrangements (for example conscription of organs after death) or changes to organ donation practice could dramatically increase the numbers of organs available, though they would conflict with currently accepted norms governing transplantation. We argue that one alternative, Organ Donation Euthanasia, would be a rational improvement over current practice regarding withdrawal of life support. It would give individuals the greatest chance of being able to help others with their organs after death. It would increase patient autonomy. It would reduce the chance of suffering during the dying process. We argue that patients should be given the choice of whether and how they would like to donate their organs in the event of withdrawal of life support in intensive care. Continuing current transplantation practice comes at the cost of death and prolonged organ failure. We should seriously consider all of the alternatives.

Introduction: Reconsidering Disorders of Consciousness in Light of Neuroscientific Evidence

Disorders of consciousness pose a substantial ethical challenge to clinical decision making, especially regarding the use of life-sustaining medical treatment. For these decisions it is paramount to know whether the patient is aware or not. Recent brain research has been striving to assess awareness by using mainly functional magnetic resonance imaging. We review the neuroscientific evidence and summarize the potential and problems of the different approaches to prove awareness. Finally, we formulate the crucial ethical questions and outline the different articles in this special issue on disorders of consciousness.

Attitudes towards end-of-life issues in disorders of consciousness: a European survey

Previous European surveys showed the support of healthcare professionals for treatment withdrawal [i.e., artificial nutrition and hydration (ANH) in chronic vegetative state (VS) patients]. The recent definition of minimally conscious state (MCS), and possibly research advances (e.g., functional neuroimaging), may have lead to uncertainty regarding potential residual perception and may have influenced opinions of healthcare professionals. The aim of the study was to update the end-of-life attitudes towards VS and to determine the end-of-life attitudes towards MCS. A 16-item questionnaire related to consciousness, pain and end-of-life issues in chronic (i.e., >1 year) VS and MCS and locked-in syndrome was distributed among attendants of medical and scientific conferences around Europe (n = 59). During a lecture, the items were explained orally to the attendants who needed to provide written yes/no responses. Chi-square tests and logistic regression analyses identified differences and associations for age, European region, religiosity, profession, and gender. We here report data on items concerning end-of-life issues on chronic VS and MCS. Responses were collected from 2,475 participants. For chronic VS (>1 year), 66% of healthcare professionals agreed to withdraw treatment and 82% wished not to be kept alive (P < 0.001). For chronic MCS (>1 year), less attendants agreed to withdraw treatment (28%, P < 0.001) and wished not to be kept alive (67%, P < 0.001). MCS was considered worse than VS for the patients in 54% and for their families in 42% of the sample. Respondents' opinions were associated with geographic region and religiosity. Our data show that end-of-life opinions differ for VS as compared to MCS. The introduction of the diagnostic criteria for MCS has not substantially changed the opinions on end-of-life issues on permanent VS. Additionally, the existing legal ambiguity around MCS may have influenced the audience to draw a line between expressing preferences for self versus others, by implicitly recognizing that the latter could be a step on the slippery slope to legalize euthanasia. Given the observed individual variability, we stress the importance of advance directives and identification of proxies when discussing end-of-life issues in patients with disorders of consciousness.

CT and MR in non-neonatal hypoxic-ischemic encephalopathy: radiological findings with pathophysiological correlations

Non-neonatal hypoxic-ischemic encephalopathy is a clinical condition often related to cardiopulmonary arrest that demands critical management and treatment decisions. Management depends mainly on the degree of neurological impairment and prognostic considerations. Computed tomography (CT) is often used to exclude associated or mimicking pathology. If any, only nonspecific signs such as cerebral edema, sulci effacement, and decreased gray matter (GM)/white matter (WM) differentiation are evident. Pseudosubarachnoid hemorrhage, a GM/WM attenuation ratio <1.18, and inverted GM attenuation are associated with a poor prognosis. Magnetic resonance (MR) imaging is more sensitive than CT in assessing brain damage in hypoxic-ischemic encephalopathy. Some MR findings have similarities to those seen pathologically, based on spatial distribution and time scale, such as lesions distributed in watershed regions and selective injury to GM structures. In the acute phase, lesions are better depicted using diffusion-weighted imaging (DWI) because of the presence of cytotoxic edema, which, on T2-weighted images, only become apparent later in the early subacute phase. In the late subacute phase, postanoxic leukoencephalopathy and contrast enhancement could be observed. In the chronic phase, atrophic changes predominate over tissue signal changes. MR can be useful for estimating prognosis when other tests are inconclusive. Some findings, such as the extent of lesions on DWI and presence of a lactate peak and depleted N-acetyl aspartate peak on MR spectroscopy, seem to have prognostic value.

Diagnosing consciousness: neuroimaging, law, and the vegetative state

In this paper, we review recent neuroimaging investigations of disorders of consciousness and different disciplines' understanding of consciousness itself. We consider potential tests of consciousness, their legal significance, and how they map onto broader themes in U.S. statutory law pertaining to advance directives and surrogate decision-making. In the process, we outline a taxonomy of themes to illustrate and clarify the variance in state-law definitions of consciousness. Finally, we discuss broader scientific, ethical, and legal issues associated with the advent of neuroimaging for disorders of consciousness and conclude with policy recommendations that could help to mitigate confusion in this realm.