Academic literature on the topic 'Unresponsive wakefulness syndrome minimally conscious state'

BACKGROUND: The period of coma in some patients after severe brain damage ends with a transition to one of the forms of chronic disorders of consciousness ― a vegetative state/unresponsive wakefulness syndrome or a minimally conscious state. Almost all patients with chronic disorders of consciousness have dysphagia of varying severity, and therefore nutrition of this category of patients is carried out initially through a nasogastric tube, and then through a gastrostomy. Early tracheostomy cannula removal may lead to the development of aspiration and pneumonia. Dysphagia is often not diagnosed in chronic disorders of consciousness patients.
 AIMS: Analysis of the results of fibrooptic endoscopic assessment of swallowing in chronic disorders of consciousness patients to identify the relationship between the presence and severity of dysphagia with the level of consciousness, data on the coma recovery scale, as well as the duration of consciousness disorders and dynamics of recovery of consciousness.
 MATERIALS AND METHODS: The study was of a prospective type, conducted in the period from 2019 to 2021. 39 chronic disorders of consciousness patients (18 ― vegetative state/unresponsive wakefulness syndrome, 18 ― minimally conscious state "minus" and minimally conscious state "plus" and 3 patients with a level of consciousness corresponding to the emergence from the minimally conscious state). The average duration of chronic disorders of consciousness was 7.79.4 months. All patients underwent a neurological examination using the CRS-R upon admission to the hospital and a month later, an endoscopic examination of the swallowing function was performed with scores calculated according to the Federal Endoscopic Dysphagia Severity Assessment Scale (FEDSS) and aspiration assessment scale in accordance with the Rosenbek criteria.
 RESULTS: Dysphagia of varying severity was detected in 36 patients (92.3%). The correlation of the total CRS-R score with the degree of dysphagia (Ro=-0.481, p=0.002) was found. The degree of dysphagia did not depend on the chronic disorders of consciousness duration.
 CONCLUSION: Regardless of the chronic disorders of consciousness severity (vegetative state/unresponsive wakefulness syndrome, minimally conscious state "minus", minimally conscious state "plus") before tracheostomy removing and switching to the oral feeding, it is necessary to perform fibrooptic endoscopic studies of swallowing to detect dysphagia, determine its degree, which is a method of preventing complications of the decanulation consequences.

Abstract Cognitive motor dissociation describes a subset of patients with disorders of consciousness who show neuroimaging evidence of consciousness but no detectable command-following behaviours. Although essential for family counselling, decision-making, and the design of rehabilitation programmes, the prognosis for patients with cognitive motor dissociation remains under-investigated. The current study included 78 patients with disorders of consciousness who showed no detectable command-following behaviours. These patients included 45 patients with unresponsive wakefulness syndrome and 33 patients in a minimally conscious state, as diagnosed using the Coma Recovery Scale-Revised. Each patient underwent an EEG-based brain-computer interface experiment, in which he or she was instructed to perform an item-selection task (i.e. select a photograph or a number from two candidates). Patients who achieved statistically significant brain-computer interface accuracies were identified as cognitive motor dissociation. Two evaluations using the Coma Recovery Scale-Revised, one before the experiment and the other 3 months later, were carried out to measure the patients’ behavioural improvements. Among the 78 patients with disorders of consciousness, our results showed that within the unresponsive wakefulness syndrome patient group, 15 of 18 patients with cognitive motor dissociation (83.33%) regained consciousness, while only five of the other 27 unresponsive wakefulness syndrome patients without significant brain-computer interface accuracies (18.52%) regained consciousness. Furthermore, within the minimally conscious state patient group, 14 of 16 patients with cognitive motor dissociation (87.5%) showed improvements in their Coma Recovery Scale-Revised scores, whereas only four of the other 17 minimally conscious state patients without significant brain-computer interface accuracies (23.53%) had improved Coma Recovery Scale-Revised scores. Our results suggest that patients with cognitive motor dissociation have a better outcome than other patients. Our findings extend current knowledge of the prognosis for patients with cognitive motor dissociation and have important implications for brain-computer interface-based clinical diagnosis and prognosis for patients with disorders of consciousness.

Patients suffering from chronic disorders of consciousness (DOC) are characterized by profound unawareness and an impairment of large-scale cortical and subcortical connectivity. In this study, we applied an electrophysiological approach aimed at identifying the residual audiomotor connectivity patterns that are thought to be linked to awareness. We measured some markers of audiomotor integration (AMI) in 20 patients affected by DOC, before and after the application of a repetitive transcranial magnetic stimulation protocol (rTMS) delivered over the left primary motor area (M1), paired to a transauricular alternating current stimulation. Our protocol induced potentiating of the electrophysiological markers of AMI and M1 excitability, paired to a clinical improvement, in all of the patients with minimally conscious state (MCS) but in none of those suffering from unresponsive wakefulness syndrome (UWS). Our protocol could be a promising approach to potentiate the functional connectivity within large-scale audiomotor networks, thus allowing clinicians to differentiate patients affected by MCS from UWS, besides the clinical assessment.

Consciousness arises from the functional interaction of multiple brain structures and their ability to integrate different complex patterns of internal communication. Although several studies demonstrated that the fronto-parietal and functional default mode networks play a key role in conscious processes, it is still not clear which topological network measures (that quantifies different features of whole-brain functional network organization) are altered in patients with disorders of consciousness. Herein, we investigate the functional connectivity of unresponsive wakefulness syndrome (UWS) and minimally conscious state (MCS) patients from a topological network perspective, by using resting-state EEG recording. Network-based statistical analysis reveals a subnetwork of decreased functional connectivity in UWS compared to in the MCS patients, mainly involving the interhemispheric fronto-parietal connectivity patterns. Network topological analysis reveals increased values of local-community-paradigm correlation, as well as higher clustering coefficient and local efficiency in UWS patients compared to in MCS patients. At the nodal level, the UWS patients showed altered functional topology in several limbic and temporo-parieto-occipital regions. Taken together, our results highlight (i) the involvement of the interhemispheric fronto-parietal functional connectivity in the pathophysiology of consciousness disorders and (ii) an aberrant connectome organization both at the network topology level and at the nodal level in UWS patients compared to in the MCS patients.

BACKGROUND: Consciousness is the state of being awake and aware of oneself and the environment. The disorders of consciousness result from pathologies that impair awareness. The development of effective comprehensive personalized interventions contributing to the recovery of consciousness in patients with chronic disorders of consciousness is one of the most pressing and challenging tasks in modern rehabilitation.
 AIM: The aim of this study was to understand structural problems of the pituitary gland, blood levels of gonadotropins and melatonin as well as brain damage markers in the blood and cerebrospinal fluid in patients with chronic disorders of consciousness and to analyze the levels of the above markers among different groups of patients depending on the level of impaired consciousness.
 MATERIALS AND METHODS: We examined 61 chronic disorders of consciousness patients and identified three groups depending on the level of consciousness including 24 patients with unresponsive wakefulness syndrome, 24 patients with a minus minimally conscious state, and 13 patients with minimally conscious state plus. We performed magnetic resonance imaging of chiasmatic-sellar region and determined blood serum levels of follicle-stimulating and luteinizing hormones and melatonin, as well as urinary level of 6-sulfatoxymelatonin and the content of brain derived neurotrophic factor (BDNF), apoptosis antigen (APO-1), FasL, glutamate, and S100 protein in the blood serum and cerebrospinal fluid.
 RESULTS: The patients were examined in the age ranging from 15 to 61 years old. Patient groups were homogeneous by the level of consciousness in terms of age and duration of chronic disorders of consciousness by the time of examination. The patients did not differ in the pituitary volume regardless of the level of consciousness. No significant differences were found between the groups with different levels of consciousness when studying the levels of melatonin in the blood serum and its metabolite in the urine. A peak in melatonin secretion was detected at 3 a.m. in 54.5 % of the patients, which can be considered as a favorable prognostic marker for further recovery of consciousness. Hypogonadotropic ovarian failure was found in 34 % of the patients, with normogonadotropic ovarian failure in the remaining patients. Serum APO-1 and BDNF levels were significantly higher in patients with minimally conscious state relative to those with unresponsive wakefulness syndrome. Significantly lower levels of glutamate in the cerebrospinal fluid were detected in women with unresponsive wakefulness syndrome compared to patients with minimally conscious state.
 CONCLUSIONS: Further in-depth examination and accumulation of data on patients with chronic disorders of consciousness may provide an opportunity to identify highly informative markers for predicting outcomes and to develop new effective approaches to rehabilitation of consciousness in this category of patients.

The minimally conscious state presents unique ethical, legal, and decision-making challenges because of the combination of diminished awareness, phenomenal experience, and diminished or absent communication. As medical expertise develops and technology advances, it is likely that more and more patients with disorders of consciousness will be recognized as being in the minimally conscious state, with minimal to no ability to participate in medical decision-making. Here we provide guidance useful for surrogates and medical professionals at any medical decision point, not merely for end-of-life decision-making. We first consider the legal landscape: precedent abounds regarding unconscious patients in coma or the vegetative state/Unresponsive Wakefulness Syndrome (VS/UWS), but there is little legal precedent involving patients in the minimally conscious state. Next we consider surrogates’ ethical authority to make medical decisions on behalf of patients with disorders of consciousness. In everyday medical decision-making, surrogates generally encounter few, if any, restrictions so long as they adhere to an idealized hierarchy of decision-making standards designed to honor patient autonomy as much as possible while ceding to the reality of what may or may not be known about a patient’s wishes. We conclude by proposing an ethically informed, practical guide for surrogate decision-making on behalf of patients in the minimally conscious state.

Diagnosis of patients with disorders of consciousness (comprising coma, vegetative state/unresponsive wakefulness syndrome, and minimally conscious state) has long been dependent on unstandardized behavioral tests. The arrival of standardized behavioral tools, and especially the Coma Recovery Scale revised, uncovered a high rate of misdiagnosis. Ancillary techniques, such as brain imaging and electrophysiological examinations, are ever more often being deployed to aid in the search for remaining consciousness. They are used to look for brain activity patterns similar to those found in healthy controls. The development of portable and cheaper devices will make these techniques more widely available.

La conscience comporte deux composantes, l’éveil et l’expérience consciente. L’expérience consciente englobe la conscience de soi ou conscience interne, et la conscience de l’environnement ou conscience externe. Trois réseaux cérébraux majeurs ont été décrits. Le réseau du mode par défaut sous-tend l’activité mentale tournée vers soi. Le réseau exécutif central est impliqué dans des activités cognitives tournées vers l’environnement. Le réseau de la saillance sous-tend la détection de stimuli saillants internes et externes, et permet une bascule dynamique entre le réseau du mode par défaut et le réseau exécutif central.Suite à un coma, certains patients restent en état chronique de conscience altérée, soit avec un syndrome d’éveil non répondant, soit en état de conscience minimale. Le syndrome d’éveil non répondant est caractérisé par une absence de comportements conscients. L’état de conscience minimale s’accompagne de comportements conscients, comme la poursuite visuelle ou la réponse à une commande, qui apparaissent de manière fluctuante. Des déficits moteurs et cognitifs associés peuvent compliquer la détection de signes de conscience au chevet de ces patients cérébrolésés, et entraîner une sous-évaluation de leur état de conscience.Les objectifs principaux de ce travail sont d’affiner l’évaluation de l’état de conscience en détectant d’éventuelles capacités résiduelles cachées ; de caractériser des corrélats anatomo-fonctionnels de l’altération de la conscience ; et d’étudier l’effet de la stimulation cérébrale profonde sur l’apparition de comportements conscients chez des patients avec altération chronique de la conscience.Concrètement, nous avons développé un protocole d’IRM fonctionnelle de traitement du langage avec charge émotionnelle graduée, pour permettre de détecter d’éventuelles capacités résiduelles cachées chez ces patients non communicants. Nous avons ensuite mené une étude de connectivité fonctionnelle au repos de régions sous-corticales et de réseaux corticaux impliqués dans la conscience interne et externe, dans un groupe de treize patients avec altération chronique de la conscience. Nous avons mis en évidence une dégradation des interactions entre le réseau de la saillance et le réseau du mode par défaut, ainsi qu’avec les thalami et les pallidums. Nous avons au préalable développé une méthode d’amélioration de la segmentation automatique de ces régions sous-corticales. Enfin, nous avons mené une étude de stimulation cérébrale profonde auprès de cinq patients avec altération chronique de la conscience, en ciblant les thalami et les pallidums. La stimulation a permis l’apparition de comportements conscients chez deux d’entre eux, associée à une augmentation du métabolisme des régions cérébrales impliquées dans la conscience interne. L’ensemble de ces résultats permet d’alimenter la réflexion sur de nouvelles pistes thérapeutiques pour les patients en état de conscience altérée<br>Consciousness can be divided into two major components: arousal and awareness. Awareness encompasses self-awareness and external awareness. Three core cerebral networks have been described. The default mode network is involved in self-related mental activity, and is internally-mediated. The central executive network is involved in externally-driven cognitive functions. The salience network is involved in the detection of salient internal and external stimuli, and plays a causal role in switching between the default mode and the central executive networks, thus mediating attention to internal and external worlds, respectively.Following a coma, some patients are left with chronic disorders of consciousness, either with unresponsive wakefulness syndrome, or in minimally conscious state. The unresponsive wakefulness syndrome is characterised by the absence of signs of awareness. The minimally conscious state is associated with minimal behavioural evidence of awareness, like visual pursuit or simple command following. The level of awareness can be underestimated by clinical assessment, owing to frequent motor and cognitive associated disorders.This thesis aims at improving awareness assessment via the detection of potential residual covert abilities, at characterising neural correlates of consciousness disorders, and at studying the effects of deep brain stimulation on conscious behaviour in patients with chronic disorders of consciousness.For the purpose of enhancing awareness detection in these non-communicative patients, we proposed a functional MRI protocol with graduated emotional charge to detect potential residual covert language-related behaviour. We then investigated the functional connectivity at rest of subcortical structures and cortical networks involved in internal and external awareness, in a group of thirteen patients with chronic disorders of consciousness. We highlighted a disruption of the functional connections between the salience and the default mode networks, as well as with the thalami and pallidums. We proposed beforehand a method to improve the automatic segmentation of these subcortical structures. Finally, we conducted a low frequency deep brain stimulation study in five patients with chronic disorders of consciousness, by dual pallido-thalamic targeting. Two patients showed improved conscious behaviour following stimulation, associated with an increase of metabolism in cortical regions involved in internal awareness

Il “blink” o “batter d’occhi” è un movimento di rapida chiusura e riapertura delle palpebre. Il “blink” può essere un movimento spontaneo, riflesso o volontario. “Blink” con identiche caratteristiche cinematiche possono avere differenti origini e significati. Per esempio, un blink può essere spontaneo quando ha la funzione fisiologica di creare un film lacrimale evitando la seccazione della cornea, può essere riflesso in riposta a stimoli esterni ed infine può essere volontario per comunicare un messaggio attraverso un canale comunicativo preservato, per esempio quando un paziente locked in cerca di comunicare gioia, accordo o disaccordo, frustrazione attraverso gli occhi (Laureys et al., 2005). Lo scopo principale di questo studio è stato quello di trovare una misura oggettiva relativa alla distinzione tra un blink spontaneo e uno volontario: il “potenziale di preparazione” (Readiness Potential). Il presente studio è quindi rilevante per due ragioni: 1. Nei soggetti sani, i blink spontanei appaiono con una frequenza di circa 1 ogni 5 secondi. Allo stesso tempo, i soggetti sani possono “controllare” il movimento spontaneo e riprodurlo in maniera intenzionale se opportunamente istruiti. In questo modo, il “blink” o “ammiccamento oculare” offre un contrasto ideale tra atto conscio e inconscio, a parità di cinematica. In questa prospettiva, l’analisi dell’attività cerebrale che precede un atto spontaneo o automatico messa a confronto con l’attività che precedere un “blink” volontario può offrire uno sguardo unico sui correlati neurali di un atto cosciente. 2. Nei pazienti con gravi cerebrolesioni, il “blink” è spesso l’unico atto motorio che può essere individuato. È infatti impossibile per molti pazienti effettuare movimenti più complessi. Per questo motivo, attraverso un condizionamento operante in cui ad uno specifico comportamento viene associato un rinforzo positivo, il nostro scopo è quello di indirizzare i pazienti ad associare un determinato tipo di “blink”, opportunamente selezionato, con un rinforzo positivo rappresentato da voci familiari/amiche che si suppone possano avere una valenza emotiva positiva per il paziente. Nella prima parte della tesi verranno introdotte le premesse teorico/sperimentali alla base dello studio e verranno presentati i materiali e metodi e i risultati relativi alla popolazione di controllo (soggetti sani). Nella seconda parte, verrà introdotto il “disturbo di coscienza” dal punto di vista clinico, il nuovo protocollo sperimentale applicato ai pazienti con disturbo di coscienza e i risultati preliminari. In conclusione, verranno valutate le potenzialità dello studio da un punto di vista teorico, da un punto di vista clinico/riabilitativo ed infine da un punto di vista etico.<br>Blinking is a rapid closing and opening of the eyelid. Eye blinks with identical kinematical features can have different origins and meanings. For example, one can blink automatically, due to a simple reflex arc – such as when moistening the cornea – or one can blink voluntarily to communicate a fundamental message – such as when a locked-in patient communicates that he/she is happy or frustrated (Laureys, et al., 2005) The main aim of the present project is to find a brain-based objective way to know whether a given blink is a meaningless automatic neural event or the endpoint of a complex conscious process. The proposal builds up on the empirical work by Kornhuber & Deecke and Benjamin Libet, who showed that the awareness of intention to move is preceded by a recordable cerebral activity called “Readiness Potential”. The present proposal is relevant for two reasons: 1. In healthy subjects, automatic blinking occurs spontaneously every 5 seconds, or so. At the same time, healthy subjects can be instructed to blink voluntarily in a controlled fashion. In this way, blinking offers the ideal contrast between unconscious and conscious acts – the physical, kinematic aspects of the movement being equal. In this perspective, analyzing brain activity prior to automatic and voluntary blinks may offer a unique insight on the neural correlates of a conscious act. 2. In patients with severe brain injuries blinking is often the only motor act that can be reliably detected. By employing operant conditioning, we aim at training patients on the association between a specific eyelid closure and a positive reinforcement. Specifically, Readiness Potential like activity will be computed on the cortical activity preceding eye blinking as a measure of “volition,” first in healthy controls and then in vegetative and minimally conscious state patients undergoing operant conditioning. In healthy controls, we will contrast spontaneous blinks against voluntary blinks. The results of this experiment are meant to explore the dynamic range of the changes in brain activity that underlies voluntary vs. spontaneous blinks in controlled conditions. In patients, detecting a progressive increase in the strength or complexity of brain activity (up to the levels obtained in healthy subjects during voluntary blinks) during the course of the conditioning sessions will indicate that their blinking might reflect a voluntary act. Ultimately, this project, if successful, will link operant conditioning to the long-standing topic of the neural substrates of a wilful decision to act, bearing important scientific/ethical implications. The novelty of this project rests on: a. Exploring, empirically, the relationships between brain activity and the will. The underlying hypothesis guiding this project is that a wilful act should be reflected, to some measurable degree, in high levels of anticipatory brain dynamics. b. Taking Libet’s work one-step forward, by using slow cortical potentials such as the “Readiness Potential” as a neural marker of volition. c. Using the “Readiness Potential” to distinguish between spontaneous and voluntary blinks. d. Answering the critical question of whether the blinks produced by vegetative patients after a conditioning protocol are voluntary or not.

The disorders of consciousness (DOC) discussions are actual and permanent subjects for debate in the media and scientific discussion in any forum. Controversies exist in the use of present-day clinical terminology, including terms that may be pejorative in describing patients. Thw European Task Force on Disorders of Consciousness has proposed a new term, unresponsive wakefulness syndrome (UWS), to assist society in avoiding the depreciatory term “vegetative state” (VS). The author has submitted a response to the paper by Giacino et al., proposing the use of the term minimally aware state instead of minimally conscious state (MCS). The main finding in VS-UWS is the preservation of wakefulness with apparent loss of awareness. The diagnosis of VS-UWS has been made more difficult by recognition of the MCS as a transitional phase in the partial recovery of self-awareness or environmental awareness while emerging from the PVS-UWS, leading to a relative high proportion of errors. Neuroimaging techniques have expansively contributed to the study of DOC. In this area, the assessment of brain connectivity is essential to explain the pathophysiology of DOC. Magnetic resonance imaging (MRI) DW-MRT techniques have being widely used to estimate the nervous fiber pathways connecting brain regions of We propose to use graph theoretical approaches to differentiate the topological organization of white matter network in DOC. An accurate and reliable assessment of consciousness pathophysiology in DOC is critical for the subsequent management and rehabilitation, as well as medical, legal, and ethical decision-making.

Abstract The general guideline has always been that recovery of awareness is much less likely if the clinical findings of persistent vegetative state (now also termed unresponsive wakefulness) are still present after 3 months in nontraumatic coma (i.e., anoxic-ischemic encephalopathy, hypoglycemia, central nervous system infections, status epilepticus). In traumatic brain injury, 12 months are needed for reasonable certainty, but recovery to a minimally conscious state may still occur beyond this time. Early on, after a major brain injury, the diagnosis of a persistent vegetative state and its important long-term implications remain tentative at best. Long-term care of debilitated neurologic patients requires placement of a tracheostomy and percutaneous gastrostomy. Timing, indications, and treatment claims are discussed in this chapter.

Abstract Consciousness may be defined as a neurological state in which one is fully awake and aware of self and environment and has normal responses to external stimulation and inner needs. Unconsciousness is the opposite; it is a neurological state of overtly diminished responsiveness to environmental stimuli and unawareness of self and environment. Consciousness has two basic dimensions: wakefulness and awareness. Awareness requires wakefulness; however, wakefulness does not require awareness, as one can be awake but unaware. Level of consciousness exists on a continuum, from full consciousness in which the individual is awake and aware, to coma in which the individual is neither awake nor aware and is in a state of unarousable unresponsiveness. This chapter describes the disorders of consciousness, namely coma, vegetative state, minimally conscious state, and delirium, as well as the coma-like states of locked-in-syndrome and brain death.