Patients In Vegetative State Research Articles

Can fast-component of nystagmus on caloric vestibulo-ocular responses predict emergence from vegetative state in ICU?

The aim of the study was to determine if bedside caloric vestibulo-ocular responses (VOR) are able to predict consciousness recovery from clinically determined vegetative state (VS) in the ICU. Twenty-six severely brain injured patients that were clinically in VS were included. Horizontal VOR were tested at bedside by cold-water irrigation of the external auditory canal. Visual inspection evaluated the presence of a slow drift toward the side of stimulation (slow-component of nystagmus or tonic deviation) as well as the presence of a rapid compensatory movement/jerk back to the midline (fast-component of nystagmus). Patients were then divided into two groups according to whether they eventually regained consciousness or not. Patients were 59 ± 21 years old. Thirteen out of 26 patients ultimately recovered consciousness and 13 remained unconscious. Thirteen patients (100%) presented a slow-component of nystagmus during VOR testing in the group that recovered consciousness and 11 (85%) in the group that remained unconscious. All the patients that recovered consciousness (13, 100%) presented a fast-component of nystagmus during VOR testing compared to only one of 11 patients (8%) in the group that remained unconscious. Sensitivity of fast-component of nystagmus during VOR testing to predict recovering of consciousness was 1.00, specificity was 0.92, positive predictive value was 0.93 and negative predictive value was 1.00. Bedside VOR testing in clinically VS patients seems able to predict consciousness recovery from vegetative state and could help to preclude active medical treatment withdrawal and to indicate the need for further complementary explorations, i.e. event-related potentials, functional MRI or PET-scan.

Intrathecal baclofen therapy in severe head injury, first time in Nepal, a technique suitable for underdeveloped countries

Intrathecal baclofen (ITB) has been found to be helpful not only for spasticity but also for unconsciousness in a vegetative patient. This is the first case of ITB in Nepal, and here we discuss the effectiveness of ITB for spasticity in a patient in vegetative state. We also discuss about a simple technique for ITB used in Nepal where baclofen pump is not available. Here, we present a case of a 40-year-old male patient who had severe head injury with diffuse axonal injury treated conservatively. He went on to a vegetative state and subsequently developed severe spasticity of all the limbs. ITB was started under the guidance of one of the authors , Prof. Taira. Baclofen was injected to the spinal intrathecal space through a catheter which is used for spinal anesthesia. Spasticity improved significantly and his higher mental function also showed signs of improvement. He finally became fully conscious and well oriented. ITB is very useful in cases of severe spasticity and vegetative condition, a state of unconsciousness lasting longer than a few weeks. Even with a simple technique in the absence of baclofen pump, ITB can be used with its optimum effect.

PTMS43 Reduced intracortical modulation in patients in vegetative state after a traumatic brain injury

PTMS43 Reduced intracortical modulation in patients in vegetative state after a traumatic brain injury

Paroxysmal Sympathetic Hyperactivity (Sympathetic Storm) in a Patient with Permanent Vegetative State

There are many people living in a permanent vegetative state in the United States. We report the first case of a patient in permanent vegetative state (PVS) who developed paroxysmal sympathetic hyperactivity (sympathetic storm) 8 months after the hypoxic brain injury that lead to PVS. Paroxysmal sympathetic hyperactivity is a relatively common complication early in the course of traumatic brain injury. Recognition of the clinical presentation of this syndrome is important to palliative and hospice care providers who may be caring for patients with PVS. The treatment of sympathic hyperactivity to reduce potential physical suffering includes medications targeted to the sympathetic nervous system.

Unconscious High-Level Information Processing

Theories about the neural correlates and functional relevance of consciousness have traditionally assigned a crucial role to the prefrontal cortex in generating consciousness as well as in orchestrating high-level conscious control over behavior. However, recent neuroscientific findings show that prefrontal cortex can be activated unconsciously. The depth, direction, and scope of these activations depend on several top-down factors such as the task being probed (task-set, strategy) and on (temporal/spatial) attention. Regardless, such activations—when mediated by feedforward activation only—do not lead to a conscious sensation. Although unconscious, these prefrontal activations are functional, in the sense that they are associated with behavioral effects of cognitive control, such as response inhibition, task switching, conflict monitoring, and error detection. These findings challenge the pivotal role of the prefrontal cortex in consciousness. Instead, it appears that specific brain areas (or cognitive modules) may support specific cognitive functions but that consciousness is independent of this. Conscious sensations arise only when the brain areas involved engage in recurrent interactions enabling the long-lasting exchange of information between brain regions. Moreover, recent evidence suggests that also the state of consciousness, for example, in vegetative state patients or during sleep and anesthesia, is closely related to the scope and extent of residual recurrent interactions among brain regions.

Pascal’s Wager and Deciding About the Life-Sustaining Treatment of Patients in Persistent Vegetative State

An adaptation of Pascal’s Wager argument has been considered useful in deciding about the provision of life-sustaining treatment for patients in persistent vegetative state. In this article, I assess whether people making such decisions should resort to the application of Pascal’s idea. I argue that there is no sufficient reason to give it an important role in making the decisions.

Cognitive processes in disorders of consciousness as revealed by EEG time–frequency analyses

Objective Although behavioral evaluation of awareness in disorders of consciousness is difficult it remains the clinical standard. We believe that the refinement of EEG and analyses techniques would improve our characterization of those patients. Methods We focused on cognitive processing in a sample of 12 control subjects, eight vegetative-state patients, and 13 patients in the minimally consciousness state using EEG. We used an ‘active paradigm’ which asks subjects to follow instructions, specifically to actively count own or other names as compared to passively listening to them. EEG data was then analyzed using an advanced EEG analysis technique. Results Results revealed that all groups exhibit a stronger theta-synchronization to their own names when forced to count them. We also observed a delay in theta power in response to targets relative to non-targets when participants were instructed to count their own name. Conclusion Active paradigms are able to induce a different oscillatory activity compared to passive paradigms. Differences between controls and the pathologic groups are prominent in the theta- and alpha-band. Significance Time–frequency analyses allow to focus on distinct cognitive processes in patients with disorders of consciousness and thereby contribute to a refined understanding of severely brain-injured patients.

Source imaging of QEEG as a method to detect awareness in a person in vegetative state

Background: Assessment of awareness in patients with severe brain injury remains subjective, although patients with even limited awareness (e.g. minimal conscious state, MCS) have different prognoses and treatment than those in vegetative state (VS). Recently, task appropriate differential regional activation in VS has been reported using fMRI during mental imagery.Primary objective: Demonstration of conscious awareness in reproducible differential EEG source localization images in a VS patient reflecting requested mental imagery was performed.Methods: A VS patient (with re-test) and a normal control were requested to imagine singing and to mentally perform serial subtraction, while EEG was recorded. QEEG source localization was performed to identify regions of brain activation in response to tasks.Results: Replicable distinctive activation of brain areas appropriate for each task was seen in the VS patient and control. Frequency spectra shifted to beta, with significant source activation in regions including the bilateral anterior cingulate, insula, left caudate and dorsolateral pre-frontal cortex to singing and the putamen, insula, left pre-frontal cortex and right temporal gyrus to subtraction by 7's.Conclusions: Results from this single case suggests the potential utility of QEEG source localization images to detect awareness in patients clinically diagnosed as being in VS. This indicates the possibility that EEG may serve as an important adjunct to the assessment of awareness in patients with disorders of consciousness in the clinical setting.

Pharmacological and electrical stimulation in chronic disorders of consciousness: New insights and future directions

Background: Chronic disorders of consciousness are costly and challenging conditions to treat. Although recent studies that have tested pharmacological and electrical stimulation for these conditions are promising, the optimal intervention, mechanisms of action and side effects of these experimental therapies are unclear.Objective: To systematically review the clinical results of treatments for vegetative state (VS) and minimally conscious state (MCS) from the last 10 years.Methods: MEDLINE, LILACS and SCOPUS were searched as data sources. Because the potential bias when search is limited to databases of peer-reviewed journals, reference lists were examined and experts in the field were contacted for other relevant or unpublished articles (i.e. negative studies). No negative unpublished studies were found. Studies were included related to therapeutic interventions in adult MCS or VS patients at least 3 and 12 months after non-traumatic and traumatic injuries, respectively. Eight studies met the inclusion criteria. The following interventions were reviewed: levodopa, amantadine, zolpidem, baclofen, dorsal column stimulation and deep brain stimulation.Conclusions: The adverse effects that were associated with these treatments were typically mild. Most of the studies demonstrated considerable improvements with the interventions, but their low strength of evidence limit the generalizability of the findings.

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.

Event-related brain activity during observation of simple motor behaviour in minimally conscious state (MCS) patients

Event Abstract Back to Event Event-related brain activity during observation of simple motor behaviour in minimally conscious state (MCS) patients Julia Lechinger1*, Nicole Chwala-Schlegel1, Theresa Stemeseder1, Robert Fellinger2 and Manuel Schabus1 1 Lab for Sleep & Consciousness, Univ. of Salzburg, Austria 2 Oscillations, Brain & Thinking Laboratory, Univ. of Salzburg, Austria Estimating cognitive functioning in patients suffering from Disorders of Consciousness (DOC) by use of behavioural measures is often challenging. Therefore it can be highly desirable to identify brain correlates such as event-related electroencephalography (EEG) which can be systematically associated with specific diagnoses. EEG from 10 Vegetative State (VS) and 7 Minimally Conscious State (MCS) patients was recorded while patients were shown 2.5 sec videos displaying a right or left arm grabbing a cup and moving it towards an invisible mouth. At the same time the respective command was presented auditorily (“grab right/left and drink”). Event-related de-/synchronisation (ERD/ERS) was calculated and repeated measures ANOVAS DIAGNOSIS x HEMI were conducted for frequencies theta (4-6 Hz), alpha1 (8-10 Hz) and sensory motor rhythm (SMR, 12-15 Hz) as well as for five poststimulus 500 ms windows. First analysis showed that during watching 2.5 sec videos displaying simple motor behaviour MCS patients showed stronger parieto-occipital alpha1 ERD than VS patients [left arm movement (lARM): 500-1000 ms, F = 6.57, p < .05; right arm movement (rARM): 1500-200 0ms, contralaterally only, F = 5.43, p < .05]. Furthermore SMR ERS was stronger in MCS than VS patients at central sites [lARM:1500-2000, contralaterally stronger, F = 6.05, p < .05; rARM: 1000-1500 ms, F = 8.7, p < .05] as well as at parietal sites [lARM: 1000-1500 ms, F = 11.96, p < .01; rARM: 1000-1500, F = 6.33, p < .05]. Here MCS patients - as compared to VS patients - showed specific brain activation in the alpha and SMR frequency band indicating that they were to some extent able to understand and to mirror a simple reaching movement. Keywords: EEG, Neuropsychiatry Conference: XI International Conference on Cognitive Neuroscience (ICON XI), Palma, Mallorca, Spain, 25 Sep - 29 Sep, 2011. Presentation Type: Poster Presentation Topic: Poster Sessions: Neuropsychiatric Applications Citation: Lechinger J, Chwala-Schlegel N, Stemeseder T, Fellinger R and Schabus M (2011). Event-related brain activity during observation of simple motor behaviour in minimally conscious state (MCS) patients. Conference Abstract: XI International Conference on Cognitive Neuroscience (ICON XI). doi: 10.3389/conf.fnhum.2011.207.00237 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 21 Nov 2011; Published Online: 28 Nov 2011. * Correspondence: Dr. Julia Lechinger, Lab for Sleep & Consciousness, Univ. of Salzburg, Salzburg, Austria, julia.lechinger@sbg.ac.at Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Julia Lechinger Nicole Chwala-Schlegel Theresa Stemeseder Robert Fellinger Manuel Schabus Google Julia Lechinger Nicole Chwala-Schlegel Theresa Stemeseder Robert Fellinger Manuel Schabus Google Scholar Julia Lechinger Nicole Chwala-Schlegel Theresa Stemeseder Robert Fellinger Manuel Schabus PubMed Julia Lechinger Nicole Chwala-Schlegel Theresa Stemeseder Robert Fellinger Manuel Schabus Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Opportunity for Inpatient Brain Injury Rehabilitation for Persons in a Vegetative State

: The aim of this study was to document physicians' opinions on inpatient rehabilitation care for working-age patients in vegetative state after new acquired brain injury, given the absence of an established standard of post-acute care. : A postal survey of 3259 Swedish physicians was conducted. : Survey response rate was 33%. Of survey respondents, 51% reported that they knew the definition of vegetative state. Transfer of vegetative patients from acute care to inpatient rehabilitation was considered always warranted by 54% and never or only sometimes warranted by 31% of survey respondents, whereas 15% did not know or did not answer. Rehabilitation physicians most often considered an inpatient rehabilitation stay of around 3 mos to be appropriate, but there was a lack of consensus. Discharge from acute care direct to social care at least sometimes was reported by 39% of physicians. : Physicians' opinions vary considerably on appropriate post-acute care for patients in vegetative state after acquired brain injury. This may impact on rates of referral and admission to rehabilitation units. Consensus is needed on a minimum period for and extent of rehabilitation interventions. Educational interventions should be targeted broadly to reach the wide range of specialties that may have responsibility for acute care of these patients.

Sea Slugs, Subliminal Pictures, and Vegetative State Patients: Boundaries of Consciousness in Classical Conditioning

Classical (trace) conditioning is a specific variant of associative learning in which a neutral stimulus leads to the subsequent prediction of an emotionally charged or noxious stimulus after a temporal gap. When conditioning is concurrent with a distraction task, only participants who can report the relationship (the contingency) between stimuli explicitly show associative learning. This suggests that consciousness is a prerequisite for trace conditioning. We review and question three main controversies concerning this view. Firstly, virtually all animals, even invertebrate sea slugs, show this type of learning; secondly, unconsciously perceived stimuli may elicit trace conditioning; and thirdly, some vegetative state patients show trace learning. We discuss and analyze these seemingly contradictory arguments to find the theoretical boundaries of consciousness in classical conditioning. We conclude that trace conditioning remains one of the best measures to test conscious processing in the absence of explicit reports.

Functional imaging reveals movement preparatory activity in the vegetative state.

The vegetative state (VS) is characterized by the absence of awareness of self or the environment and preserved autonomic functions. The diagnosis relies critically on the lack of consistent signs of purposeful behavior in response to external stimulation. Yet, given that patients with disorders of consciousness often exhibit fragmented movement patterns, voluntary actions may go unnoticed. Here we designed a simple motor paradigm that could potentially detect signs of purposeful behavior in VS patients with mild to severe brain damage by examining the neural correlates of motor preparation in response to verbal commands. Twenty-four patients who met the diagnostic criteria for VS were recruited for this study. Eleven of these patients showing preserved auditory evoked potentials underwent functional magnetic resonance imaging (fMRI) to test for basic speech processing. Five of these patients, who showed word related activity, were included in a second fMRI study aimed at detecting functional changes in premotor cortex elicited by specific verbal instructions to move either their left or their right hand. Despite the lack of overt muscle activity, two patients out of five activated the dorsal premotor cortex contralateral to the instructed hand, consistent with movement preparation. Our results may reflect residual voluntary processing in these two patients. We believe that the identification of positive results with fMRI using this simple task, may complement the clinical assessment by helping attain a more precise diagnosis in patients with disorders of consciousness.

An Audit about Music Therapy Assessments and Recommendations for Adult Patients Suspected to be in a Low, Awareness State

In neuro-rehabilitation, the role of music therapy is expanding to include assessment of patients with severely-altered states of consciousness. Diagnosis of these conditions is a complex task for all, and cases of misdiagnosis have been reported. Aggregated findings from 33 music therapy assessments of patients suspected of being in a low awareness state are described and discussed here. The Music Therapy Assessment Tool for Low Awareness States (MATLAS) was used during these assessments. All assessments were offered as part of a specialist multidisciplinary assessment package. A brief description of the patient group is supplied, along with details regarding the assessment tool and the recommendations that followed. In summary, a difference in the time it took to assess patients in vegetative state (VS) as compared to those in minimally conscious state (MCS) was found and, on average, the assessment of those in VS took less time to complete than for those in MCS. A greater range in session length was found for patients in VS, as compared to those in MCS. Generally after the assessments, patients in VS were likely to be admitted to a sensory regulation group administered by a music therapy assistant, supervised by a qualified music therapist, to enable the continued collection of behavioral responses to stimuli. Patients in MCS were admitted to a music therapy treatment program offered by a qualified music therapist. Ongoing work is recommended to advance the assessment and treatment of this patient population, and to consolidate the role of music therapy with this population.

Specific and nonspecific thalamocortical functional connectivity in normal and vegetative states

Recent theoretical advances describing consciousness from information and integration have highlighted the unique role of the thalamocortical system in leading to integrated information and thus, consciousness. Here, we examined the differential distributions of specific and nonspecific thalamocortical functional connections using resting-state fMRI in a group of healthy subjects and vegetative-state patients. We found that both thalamic systems were widely distributed, but they exhibited different patterns. Nonspecific connections were preferentially associated with brain regions involved in higher-order cognitive processing, self-awareness and introspective mentalizing (e.g., the dorsal prefrontal and anterior cingulate cortices). In contrast, specific connections were prevalent in the ventral and posterior part of the prefrontal and precuneus, known involved in representing externally-directed attentions. Significant reductions of functional connectivity in both systems, especially the nonspecific system, were observed in VS. These data suggest that brain networks sustaining information and integration may be differentiated by the nature of their thalamic functional connectivity.

Observations on the Ethical and Social Aspects of Disorders of Consciousness

The care of chronically unconscious patients raises vexing medical, ethical, and social questions concerning diagnosis, prognosis, communication with family members, and decision making, including the withdrawal of life support. We provide updates on major controversies surrounding disorders of consciousness. Issues such as withdrawal of artificial nutrition and hydration - which had been considered "settled" by many in the medical, legal and ethical communities - have resurfaced under the pressure of social groups and religious authorities. Some assumptions about the level of awareness and the prognosis of vegetative state and minimal conscious patients are questioned by advances in clinical care because of insights produced by neuroscience research techniques, particularly functional neuroimaging. Both the clinical and neuroscience dimensions of disorders of consciousness raise complex issues such as resource allocation and high levels of diagnostic inaccuracies (at least, for the vegetative state). We conclude by highlighting areas needing further research and collaboration.

TCD Diastolic Velocity Decay and Pulsatility Index Increment in PVS Cases

Functional neuroimaging has provided new insights for assessing cerebral function in persistent vegetative state patients (PVS). Compared to controls, positron emission tomography and single photon emission tomography have shown a substantial reduction of global brain cerebral glucose metabolism and perfusion in PVS. Doppler ultrasonography (TCD) assesses local blood flow velocity and direction in the proximal portions of large intracranial arteries; it is a noninvasive technique, and it can be carried out at the bedside. To date, few studies have applied TCD to study PVS. We assessed intracranial circulation by TCD in five PVS patients. The cause of brain insult was hypoxic encephalopathy in four cases, and the other suffered an embolic cerebral infarct causing a top of the basilar artery syndrome. The sample volume was set at 12 mm; power output and gain settings were maximized as needed. The temporal bone acoustic window was not suitable for intracranial vessel insonation in all patients. As an alternative, the internal carotid artery siphon was assessed by orbital insonation between 55-70 mm. Systolic velocity was within a normal range, between 44 and 62 cm/second in all cases. However, the diastolic amplitude was reduced, as well as the end diastolic velocity, and the pulsatility index was increased in all patients. We conclude that TCD diastolic velocity decrement and PI augmentation in our cases might be related to uncoupling of cerebral blood flow and cerebral metabolic rate, arising from reduced cerebral glucose consumption and oxygen uptake, after extensive brain injury.

A network approach to assessing cognition in disorders of consciousness

Conventional assessments of consciousness rely on motor responses to indicate awareness. However, overt behaviors may be absent or ambiguous in patients with disorders of consciousness (DOC) resulting in underrating capacity for cognition. fMRI during a silent picture-naming task was evaluated as an indicator of command following when conventional methods are not sufficient. A total of 10 patients with and without conventional evidence of awareness, who met diagnostic criteria for the minimally conscious state (MCS) (n = 5), vegetative state (VS) (n = 3), emerged from MCS (EMCS) (n = 1), and locked-in syndrome (LIS) (n = 1), participated in this observational fMRI study. The LIS and EMCS patients engaged a complete network of essential language-related regions during the object-naming task. The MCS and 2 of the VS patients demonstrated both complete and partial preservation of the object-naming system. Patients who engaged a complete network scored highest on the Coma Recovery Scale-Revised. This study supports the view that fMRI during object naming can elicit brain activations in patients with DOC similar to those observed in healthy subjects during command following, and patients can be stratified by completeness of the engaged neural system. These results suggest that activity of the language network may serve as an indicator of high-level cognition and possibly volitional processes that cannot be discerned through conventional behavioral assessment alone.

A network approach to assessing cognition in disorders of consciousness

Objective: Conventional assessments of consciousness rely on motor responses to indicate awareness. However, overt behaviors may be absent or ambiguous in patients with disorders of consciousness (DOC) resulting in underrating capacity for cognition. fMRI during a silent picture-naming task was evaluated as an indicator of command following when conventional methods are not sufficient. Methods: A total of 10 patients with and without conventional evidence of awareness, who met diagnostic criteria for the minimally conscious state (MCS) (n = 5), vegetative state (VS) (n = 3), emerged from MCS (EMCS) (n = 1), and locked-in syndrome (LIS) (n = 1), participated in this observational fMRI study. Results: The LIS and EMCS patients engaged a complete network of essential language-related regions during the object-naming task. The MCS and 2 of the VS patients demonstrated both complete and partial preservation of the object-naming system. Patients who engaged a complete network scored highest on the Coma Recovery Scale-Revised. Conclusions: This study supports the view that fMRI during object naming can elicit brain activations in patients with DOC similar to those observed in healthy subjects during command following, and patients can be stratified by completeness of the engaged neural system. These results suggest that activity of the language network may serve as an indicator of high-level cognition and possibly volitional processes that cannot be discerned through conventional behavioral assessment alone.