Accurately predicting functional outcomes for unresponsive patients with acute brain injury is a medical, scientific and ethical challenge. This prospective study assesses how a multimodal approach combining various numbers of behavioral, neuroimaging and electrophysiological markers affects the performance of outcome predictions. We analyzed data from 349 patients admitted to a tertiary neurointensive care unit between 2009 and 2021, categorizing prognoses as good, uncertain or poor, and compared these predictions with observed outcomes using the Glasgow Outcome Scale–Extended (GOS-E, levels ranging from 1 to 8, with higher levels indicating better outcomes). After excluding cases with life-sustaining therapy withdrawal to mitigate the self-fulfilling prophecy bias, our findings reveal that a good prognosis, compared with a poor or uncertain one, is associated with better one-year functional outcomes (common odds ratio (95% CI) for higher GOS-E: OR = 14.57 (5.70–40.32), P < 0.001; and 2.9 (1.56–5.45), P < 0.001, respectively). Moreover, increasing the number of assessment modalities decreased uncertainty (OR = 0.35 (0.21–0.59), P < 0.001) and improved prognostic accuracy (OR = 2.72 (1.18–6.47), P = 0.011). Our results underscore the value of multimodal assessment in refining neuroprognostic precision, thereby offering a robust foundation for clinical decision-making processes for acutely brain-injured patients. ClinicalTrials.gov registration: NCT04534777.

Les troubles neurologiques liés au déficit en DOCK 8, déficit immunitaire autosomique récessive, sont rares. Des cas d'encéphalites, de lymphomes et de vascularites ont été décrits. Nous rapportons le cas d'une dissection intracrânienne. Patient âgé de 19 ans, connu pour un déficit en DOCK 8 et suivi depuis l'âge de 14 ans en pédiatrie, est pris en charge en alerte thrombolyse pour l'installation brutale d'une hémiparésie gauche incluant la face, avec à son arrivée un score NIHSS à 6. À l'interrogatoire, il rapporte des céphalées depuis dix jours. L'IRM cérébrale initiale montre un AVC ischémique aigu du territoire sylvien droit (ACM) superficiel et profond avec un aspect sténosé de l'ACM proximale. Une recanalisation par voie endovasculaire est décidée en urgence. L'artériographie diagnostique et thérapeutique met en évidence une sténose filiforme longue de la portion M1 de l'ACM droite associée à une dilatation anévrysmale en aval, ainsi qu'un flap intimal, typique d'une dissection artérielle. Une pose de stent associée à une double anti-agrégation plaquettaire est effectuée. L'évolution est favorable dans les heures puis les jours suivants, avec un NIHSS à 0 et une IRM de contrôle montrant une bonne perméabilité du stent. Le reste du bilan, effectué à la recherche d'une origine cardio-embolique ou inflammatoire, est normal. Le déficit en DOCK 8 (9p24) est responsable d'un déficit immunitaire combiné entraînant une lymphopénie sévère et des infections virales graves ainsi que des anomalies dans la modulation du cytosquelette des tissus conjonctifs, notamment des vaisseaux, avec des cas décrits d'anévrysmes de l'aorte et des artères rénales, et plus rarement des artères cérébrales. À notre connaissance aucun cas de dissection intracrânienne lié à cette mutation n'a été décrit à ce jour. Le déficit en DOCK 8 est rare et son spectre clinique reste à élargir, nous y participons par la description du cas clinique de ce patient, chez qui la discussion multidisciplinaire fluide (neurologues, neuroradiologues, pédiatres) a permis une prise en charge optimale.

BACKGROUND:Neurological disorders associated with SARS-CoV-2 infection represent a clinical challenge because they encompass a broad neurological spectrum and may occur before the diagnosis of COVID-19. METHODS:In this monocentric retrospective case series, medical records from patients with acute neurological disorders associated with SARS-CoV-2 infection from medicine departments of an academic center in Paris area were collected between March 15th and May 15th 2020. Diagnosis of SARS-CoV-2 was ascertained through specific RT-PCR in nasopharyngeal swabs or based on circulating serum IgG antibodies. RESULTS:Twenty-six patients diagnosed with SARS-CoV-2 infection presented with neurological disorders: encephalitis (N=8), encephalopathy (N=6), cerebrovascular events (ischemic strokes N=4 and vein thromboses N=2), other central nervous system (CNS) disorders (N=4), and Guillain-Barré syndrome (N=2). The diagnosis of SARS-CoV-2 was delayed on average 1.6 days after the onset of neurological disorder, especially in case of encephalitis 3.9 days, encephalopathy 1.0 day, and cerebrovascular event 2.7 days. CONCLUSIONS:Our study confirms that COVID-19 can yield a broad spectrum of neurological disorders. Because neurological presentations of COVID-19 often occur a few days before the diagnosis of SARS-COV-2 infection, clinicians should take preventive measures such as patient isolation and masks for any new admission to avoid nosocomial infections. Anti-SARS-CoV2 antibody detection in RT-PCR SARS CoV-2 negative suspected cases is useful to confirm a posteriori the diagnosis of atypical COVID-19 presentations.

The clinical and fundamental exploration of patients suffering from disorders of consciousness (DoC) is commonly used by researchers both to test some of their key theoretical predictions and to serve as a unique source of empirical knowledge about possible dissociations between consciousness and cognitive and/or neural processes. For instance, the existence of states of vigilance free of any self-reportable subjective experience [e.g. "vegetative state (VS)" and "complex partial epileptic seizure"] originated from DoC and acted as a cornerstone for all theories by dissociating two concepts that were commonly equated and confused: vigilance and conscious state. In the present article, we first expose briefly the major achievements in the exploration and understanding of DoC. We then propose a synthetic taxonomy of DoC, and we finally highlight some current limits, caveats and questions that have to be addressed when using DoC to theorize consciousness. In particular, we show (i) that a purely behavioral approach of DoC is insufficient to characterize the conscious state of patients; (ii) that the comparison between patients in a minimally conscious state (MCS) and patients in a VS [also coined as unresponsive wakefulness syndrome (UWS)] does not correspond to a pure and minimal contrast between unconscious and conscious states and (iii) we emphasize, in the light of original resting-state positron emission tomography data, that behavioral MCS captures an important but misnamed clinical condition that rather corresponds to a cortically mediated state and that MCS does not necessarily imply the preservation of a conscious state.

Mild encephalopathy/encephalitis with reversible splenial lesion (MERS) is a transient clinico-radiological syndrome characterized by non-specific encephalopathy and specific magnetic resonance imaging (MRI) pattern. MRI shows an ovoid lesion in the mid-splenium of the corpus callosum (SCC), with signal-intensity anomaly similar to stroke but vanishing within few weeks. Although there are a lot of child MERS cases descriptions, there are just a few adult-onset reported. Our goal is to provide a better clinical and radiological description of this entity. We reported nine adult-onset cases of MERS managed in our stroke unit between 2017 and 2019. The study of our adult series suggests that epilepsy and the context of an infection are very common in MERS. Adult cases show frequent focal neurological deficits and few encephalopathies compared to children. The measurement of very low ADC values in SCC lesion is a new radiological feature of MERS that should be systematically assessed in suspected cases to differentiate this complex syndrome from SCC strokes.

Objective: To explore whether the presence of an event-related potential (ERP) “global effect” (GE+)—that corresponds to a correlate of conscious processing in the local–global auditory task—predicts behaviorally overt consciousness recovery in a large cohort of patients suffering from disorders of consciousness (DOC). Methods: We conducted a prospective study on all DOC patients evaluated during the 2009–2018 period. Behavioral examination included Coma Recovery Scale-Revised (CRS-R) scores and bedside high-density EEG recordings. Consciousness recovery was evaluated at 6 months by a structured phone interview. The predictive value of a GE+ was calculated both on survivors and on all patients. Results: A total of 236 patients with a documented outcome and technically valid EEG recordings could be included. Among them, 66 patients had a GE+ status (28%). Presence of GE+ predicted behaviorally overt consciousness recovery in survivors with high specificity (Sp = 84%) and high positive predictive value (PPV = 80%) but with low sensitivity (Se = 35%) and low negative predictive value (NPV = 42%). Positive likelihood ratio (LR+) of GE+ was superior to LR+ of initial clinical status and of ERP effect indexing unconscious auditory processing [local effect (LE)]. Interpretation: Our results demonstrate that the presence of a bedside ERP GE+ is highly predictive of behaviorally overt consciousness recovery in DOC patients, regardless of the delay, of behavioral status, and of the etiology of brain dysfunction. However, the absence of this effect is not a reliable predictor of negative outcome. This study provides Class III evidence that the presence of an ERP “global effect” predicts consciousness recovery in DOC patients.

BACKGROUND:Stroke is a leading cause of death and disability in developed countries. The major factor affecting long-term survival other than age is the disability severity caused by stroke. The modified Rankin Scale (mRS) is a global functional endpoint measurement used in acute stroke to evaluate the degree of disability or dependence in daily life activities. The objective of this study was to assess the effects of sociodemographic factors, concomitant disease states, and some measures performed in the emergency department (ED) on patients' disability.METHODS:We conducted a retrospective study on ischemic stroke patients admitted to Intensive Care Unit of three Lebanese university hospitals between June and December 2016. Patients were excluded if they had been discharged from ED without hospital admission or if mRS was not performed. The mRS was further subdivided into two categories considered as "good prognosis" (0-2 or 0-3) and "poor prognosis" (>2 or > 3).RESULTS:204 patients were included in the study with mean age of 65.4 ± 11.9 years, hypertension was the most previous concomitant past medical disease (77.1%), and 27.1% of these patients had previous history of stroke. No significant differences were found in both mRS categories for all sociodemographic factors, and past medical history except that arrhythmia was significantly more common in the higher mRS categories > 2 and > 3. Based on multivariable analysis, there was a trend for previous intake of calcium channel blocker to be associated with lower mRS at admission (beta -0.586). However, intracranial arterial stenosis, ED blood glucose > 180 mg/dL, and performing brain imaging above 20 minutes after patient presentation to ED were significantly associated with higher mRS scores at discharge with an ORa and (confidence interval) of 2.986 (0.814, 10.962), 3.301 (1.072, 1.261), and 1.138 (1.071, 9.080), respectively.CONCLUSION:mRS is affected by previous disease states, prescribed medications, and acute measures performed in ED. It is also influenced by intracranial arterial stenosis etiology, which is associated with worse outcome.

Severe brain injuries can lead to long-lasting disorders of consciousness (DoC) such as vegetative state/unresponsive wakefulness syndrome (VS/UWS) or minimally conscious state (MCS). While behavioral assessment remains the gold standard to determine conscious state, EEG has proven to be a promising complementary tool to monitor the effect of new therapeutics. Encouraging results have been obtained with invasive electrical stimulation of the brain, and recent studies identified transcranial direct current stimulation (tDCS) as an effective approach in randomized controlled trials. This non-invasive and inexpensive tool may turn out to be the preferred treatment option. However, its mechanisms of action and physiological effects on brain activity remain unclear and debated. Here, we stimulated 60 DoC patients with the anode placed over left-dorsolateral prefrontal cortex in a prospective open-label study. Clinical behavioral assessment improved in twelve patients (20%) and none deteriorated. This behavioral response after tDCS coincided with an enhancement of putative EEG markers of consciousness: in comparison with non-responders, responders showed increases of power and long-range cortico-cortical functional connectivity in the theta-alpha band, and a larger and more sustained P300 suggesting improved conscious access to auditory novelty. The EEG changes correlated with electric fields strengths in prefrontal cortices, and no correlation was found on the scalp. Taken together, this prospective intervention in a large cohort of DoC patients strengthens the validity of the proposed EEG signatures of consciousness, and is suggestive of a direct causal effect of tDCS on consciousness.

L'angiopathie amyloïde cérébrale inflammatoire est une entité rare de leucoencéphalopathie vasculaire réversible dont le mécanisme évoqué est une réaction immune dirigée contre des dépôts ß-amyloides intravasculaires cérébraux. Nous rapportons ici le cas d'une patiente de 75 ans aux antécédents de pseudo-polyarthrite rhizomélique et d'ostéoporose cortico-induite ayant présenté des troubles neurovisuels évoquant un syndrome de Balint associés à des troubles dysexécutifs et apraxiques, ainsi qu'une désorientation spatio-temporelle d'installation subaigue sur deux semaines. L'anamnèse retrouvait également des céphalées et des pics hypertensifs au moment de son admission aux urgences, sans fièvre, ni déficit focal ou évènement critique. L'IRM montrait des hypersignaux FLAIR sous-corticaux en rapport avec un œdème vasogénique étendu prédominant en temporo-occipital, de façon bilatérale et grossièrement symétrique, associés à de multiples micro-saignements périphériques et une prise de contraste leptoméningée. L'EEG décrivait un aspect d'encéphalopathie postérieure, avec de nombreuses bouffées delta symétriques et fluctuantes. L'analyse du LCS retrouvait une hyperprotéinorachie à 0,86 g/L, sans méningite, sans argument en faveur d'une infection, avec une diminution du peptide Aß42 à 362 pg/mL et un ratio Aß40/Aß42 augmenté à 261, en faveur d'un processus amyloïdogène. Une corticothérapie à forte dose a permis une régression des troubles neurovisuels et une amélioration des troubles cognitifs dès 5 jours de traitement. Le principal diagnostic différentiel de l'angiopathie amyloïde cérébrale inflammatoire est ici un syndrome d'encéphalopathie postérieure réversible (PRES), devant la symétrie des lésions radiologiques et les pics hypertensifs initiaux. Une intrication des mécanismes physiopathologiques entre ces deux entités est cependant possible, l'ouverture de la barrière hémato-encéphalique associée au PRES pouvant favoriser une réaction inflammatoire dirigée contre les dépôts ß-amyloïdes intravasculaires. Le diagnostic précoce de la forme inflammatoire d'angiopathie amyloïde cérébrale s'appuie sur des critères cliniques et radiologiques validés et doit permettre la mise en place rapide d'un traitement immunosuppresseur susceptible d'entrainer une amélioration considérable.

ObjectivesThe clinical distinction between vegetative state/unresponsive wakefulness syndrome (UWS) and minimally conscious state (MCS) is a key step to elaborate a prognosis and formulate an appropriate medical plan for any patient suffering from disorders of consciousness (DoC). However, this assessment is often challenging and may require specialised expertise. In this study, we hypothesised that pooling subjective reports of the level of consciousness of a given patient across several nursing staff members can be used to clinically detect MCS.Setting and participantsPatients referred to consciousness assessment were prospectively screened. MCS (target condition) was defined according to the best Coma Recovery Scale-Revised score (CRS-R) obtained from expert physicians (reference standard). ‘DoC-feeling’ score was defined as the median of individual subjective reports pooled from multiple staff members during a week of hospitalisation (index test). Individual ratings were collected at the end of each shift using a 100 mm Visual Analogue Scale, blinded from the reference standard. Diagnostic accuracy was evaluated using area under the receiver operating characteristic curve (AUC), sensitivity and specificity metrics.Results692 ratings performed by 83 nursing staff members were collected from 47 patients. Twenty patients were diagnosed with UWS and 27 with MCS. DoC-feeling scores obtained by pooling all individual ratings obtained for a given patient were significantly greater in patients with MCS than with UWS (59.2 mm (IQR: 27.3–77.3) vs 7.2 mm (IQR: 2.4–11.4); p<0.001) yielding an AUC of 0.92 (95% CI 0.84 to 0.99).ConclusionsDoC-feeling capitalises on the expertise of nursing staff to evaluate patients’ consciousness. Together with the CRS-R as well as with brain imaging, DoC-feeling might improve diagnostic and prognostic accuracy of patients with DoC.

L’astrocytome anaplasique (AA) est un gliome de haut grade à présentations cliniques variées. Son diagnostic parfois difficile, entraîne une errance diagnostique et un retard thérapeutique préjudiciable. Nous rapportions le cas d’un patient âgé de 61 ans, qui a présenté un état de mal épileptique fébrile avec un syndrome confusionnel et hémiparésie droite. L’étude du LCR objectiva une hyperprotéinorachie sans cellules avec PCR du virus herpes simplex (HSV) négative. L’immunophénotypage et la recherche de cellules tumorales étaient négatifs. L’IRM cérébrale montrait un hypersignal FLAIR et diffusion temporal interne gauche, sans prise de contraste ni remaniement hémorragique. L’EEG révélait des ondes lentes pseudo-périodiques (PLEDs) à gauche. Un traitement initial par Aciclovir et antiépileptiques a permis une récupération clinique partielle sans amélioration radiologique à l’IRM de contrôle. La PCR HSV sur des ponctions lombaires de contrôle revenait toujours négative. La TEP-IRM cérébrale objectivait une lésion infiltrative en hypersignal FLAIR centré sur le cortex, avec une prise de contraste punctiforme, une hyperfixation modérée de la F-DOPA, un rapport T/S = 1,1 et un profil spectroscopique tumoral dans l’œdème péri-lésionnel, avec une inversion du rapport Cho/NAA. La biopsie avec étude histologique objectivait un astrocytome anaplasique de grade III, IDH1 R132H négatif, ATRX maintenu, EGFR++. La radio-chimiothérapie selon STUPP a entraîné une régression des lésions. Devant des crises épileptiques, une confusion mentale fébrile, des signes focaux avec lésion temporale à l’IRM, le diagnostic d’encéphalite herpétique paraissait évident. Malgré l’amélioration clinique, le doute persistait vu la négativité de la PCR HSV dans le LCR et l’aspect en partie atypique de l’IRM. Le recours à la biopsie cérébrale nous a permis d’établir le diagnostic d’AA. Cette observation illustre la possibilité d’errance diagnostique dont peut faire l’objet un astrocytome anaplasique, au pronostic péjoratif pourtant. Elle rappelle l’intérêt d’élargir les investigations devant des tableaux d’encéphalite herpétique ou auto-immune atypiques.

Objectives The clinical distinction between vegetative state/unresponsive wakefulness syndrome (UWS) and minimally conscious state (MCS) is a key step to elaborate a prognosis and formulate an appropriate medical plan for any patient suffering from disorders of consciousness (DoC). However, this assessment is often challenging and may require specialized expertise. In this study, we hypothesized that pooling subjective reports of the level of consciousness of a given patient across several nursing staff members can be used to clinically detect MCS. Setting and Participants Patients referred for consciousness assessment were prospectively screened. MCS (target condition) was defined according to the best Coma Recovery Scale-Revised score (CRS-R) obtained from expert physicians (reference standard). “DoC-feeling” score consisted in the median value of multiple ratings of patient’s behavior observation pooled from multiple staff members during a week of hospitalisation (index test). Individual ratings were collected at the end of each shift using a 100mm visual analog scale, blinded from the reference standard. Diagnostic accuracy was evaluated using area under the receiver operating characteristic curve (AUC), sensitivity and specificity metrics. Results 692 ratings performed by 83 nursing staff members were collected from 47 patients. Twenty patients were in a UWS and 27 in a MCS. DoC-feeling scores obtained by pooling all individual ratings obtained for a given patient were significantly greater in MCS than in UWS patients (59.2 mm [IQR: 27.3-77.3] vs. 7.2 mm [IQR: 2.4-11.4]; p<0.001) yielding an AUC of 0.92 (95%CI: 0.84-0.99). Conclusions DoC-feeling capitalizes on the expertise of nursing staff to evaluate patients’ consciousness. Together with the CRS-R as well as with brain imaging, DoC-feeling might improve diagnostic and prognostic accuracy of DoC patients. Strengths and limitations of this study We designed a new behavioural tool called “DoC-feeling” to help face the clinical challenge of the detection of Minimally Conscious State in patients suffering from disorders of consciousness (DoC) “DoC-feeling score” quantifies nursing staff’s subjective perception of patient’s consciousness by pooling multiple assessments obtained from multiple caregivers (“wisdom of the crowds”) This score which requires no particular training showed a very good accuracy when compared to the gold standard (repeated expert clinical assessment using the Coma Recovery Scale – Revised (CRS-R)) A validation in a separate cohort would help to determine its place in consciousness assessment This score should be tested not only against the CRS-R but also against brain-imaging techniques to test for its capacity to detect covert signs of consciousness

BACKGROUND:Mismatch negativity (MMN) is the neurophysiological correlate of cognitive integration of novel stimuli. Although MMN is a well-established predictor of awakening in non-sedated comatose patients, its prognostic value in deeply sedated critically ill patients remains unknown. The aim of this prospective, observational pilot study was to investigate the prognostic value of MMN for subsequent awakening in deeply sedated critically ill patients. METHODS:MMN was recorded in 43 deeply sedated critically ill patients on Day 3 of ICU admission using a classical 'odd-ball' paradigm that delivers rare deviant sounds in a train of frequent standard sounds. Individual visual analyses and a group level analysis of recordings were performed. MMN amplitudes were then analysed according to the neurological status (awake vs not awake) at Day 28. RESULTS:Median (inter-quartile range) Richmond Assessment Sedation Scale (RASS) at the time of recording was -5 (range, from -5 to -4.5). Visual detection of MMN revealed a poor inter-rater agreement [kappa=0.17, 95% confidence interval (0.07-0.26)]. On Day 28, 30 (70%) patients had regained consciousness while 13 (30%) had not. Quantitative group level analysis revealed a significantly greater MMN amplitude for patients who awakened compared with those who had not [mean (standard deviation) = -0.65 (1.4) vs 0.08 (0.17) μV, respectively; P=0.003). CONCLUSIONS:MMN can be observed in deeply sedated critically ill patients and could help predict subsequent awakening. However, visual analysis alone is unreliable and should be systematically completed with individual level statistics.

Determining the state of consciousness in patients with disorders of consciousness is a challenging practical and theoretical problem. Recent findings suggest that multiple markers of brain activity extracted from the EEG may index the state of consciousness in the human brain. Furthermore, machine learning has been found to optimize their capacity to discriminate different states of consciousness in clinical practice. However, it is unknown how dependable these EEG markers are in the face of signal variability because of different EEG configurations, EEG protocols and subpopulations from different centres encountered in practice. In this study we analysed 327 recordings of patients with disorders of consciousness (148 unresponsive wakefulness syndrome and 179 minimally conscious state) and 66 healthy controls obtained in two independent research centres (Paris Pitié-Salpêtrière and Liège). We first show that a non-parametric classifier based on ensembles of decision trees provides robust out-of-sample performance on unseen data with a predictive area under the curve (AUC) of ~0.77 that was only marginally affected when using alternative EEG configurations (different numbers and positions of sensors, numbers of epochs, average AUC = 0.750 ± 0.014). In a second step, we observed that classifiers based on multiple as well as single EEG features generalize to recordings obtained from different patient cohorts, EEG protocols and different centres. However, the multivariate model always performed best with a predictive AUC of 0.73 for generalization from Paris 1 to Paris 2 datasets, and an AUC of 0.78 from Paris to Liège datasets. Using simulations, we subsequently demonstrate that multivariate pattern classification has a decisive performance advantage over univariate classification as the stability of EEG features decreases, as different EEG configurations are used for feature-extraction or as noise is added. Moreover, we show that the generalization performance from Paris to Liège remains stable even if up to 20% of the diagnostic labels are randomly flipped. Finally, consistent with recent literature, analysis of the learned decision rules of our classifier suggested that markers related to dynamic fluctuations in theta and alpha frequency bands carried independent information and were most influential. Our findings demonstrate that EEG markers of consciousness can be reliably, economically and automatically identified with machine learning in various clinical and acquisition contexts.

Background: The prognosis value of early clinical diagnosis of consciousness impairment is documented by an extremely limited number of studies, whereas it may convey important information to guide medical decisions. Objective: We aimed at determining if patients diagnosed at an early stage (< 90 days after brain injury) as being in the minimally conscious state (MCS) have a better prognosis than patients in the vegetative state/Unresponsive Wakefulness syndrome (VS/UWS), independent of care limitations or withdrawal decisions. Methods: Patients hospitalized in ICUs of the Pitie-Salpetriere Hospital (Paris, France) from November 2008 to January 2011 were included and evaluated behaviourally with standardized assessment and with the Coma Recovery Scale-Revised as being either in the VS/UWS or in the MCS. They were then prospectively followed until 1July 2011 to evaluate their outcome with the GOSE. We compared survival function and outcomes of these two groups. Results: Both survival function and outcomes, including consciousness recovery, were significantly better in the MCS group. This difference of outcome still holds when considering only patients still alive at the end of the study. Conclusions: Early accurate clinical diagnosis of VS/UWS or MCS conveys a strong prognostic value of survival and of consciousness recovery.

The use of cognitive evoked potentials in EEG is now part of the routine evaluation of non-communicating patients with disorders of consciousness in several specialized medical centers around the world. They typically focus on one or two cognitive markers, such as the mismatch negativity or the P3 to global auditory regularity. However it has become clear that none of these markers in isolation is at the same time sufficiently specific and sufficiently sensitive to be taken as the unique gold standard for diagnosing consciousness. A good way forward would be to combine several cognitive markers within the same test to improve evaluation. Furthermore, given the diversity of lesions leading to disorders of consciousness, it is important not only to probe whether a patient is conscious or not, but also to establish a more general and nuanced profile of the residual cognitive capacities of each patient using a combination of markers. In the present study we built a unique EEG protocol that probed 8 dimensions of cognitive processing in a single 1.5 h session. This protocol probed variants of classical markers together with new markers of spatial attention, which has not yet been studied in these patients. The eight dimensions were: (1) own name recognition, (2) temporal attention, (3) spatial attention, (4) detection of spatial incongruence (5) motor planning, and (6,7,8) modulations of these effects by the global context, reflecting higher-level functions. This protocol was tested in 15 healthy control subjects and in 17 patients with various etiologies, among which 13 could be included in the analysis. The results in the control group allowed a validation and a specific description of the cognitive levels probed by each marker. At the single-subject level, this combined protocol allowed assessing the presence of both classical and newly introduced markers for each patient and control, and revealed that the combination of several markers increased diagnostic sensitivity. The presence of a high-level effect in any of the three tested domains distinguished between minimally conscious and vegetative patients, while the presence of low-level effects was similar in both groups. In summary, this study constitutes a validated proof of concept in favor of probing multiple cognitive dimensions to improve the evaluation of non-communicating patients. At a more conceptual level, this EEG tool can help achieve a better understanding of disorders of consciousness by exploring consciousness in its multiple cognitive facets.

Engagement of various forms of attention and response preparation determines behavioral performance during stimulus-response tasks. Many studies explored the respective properties and neural signatures of each of these processes. However, very few experiments were conceived to explore their interaction. In the present work we used an auditory target detection task during which both temporal attention on the one side, and spatial attention and motor response preparation on the other side could be explicitly cued. Both cueing effects speeded response times, and showed strictly additive effects. Target ERP analysis revealed modulations of N1 and P3 responses by these two forms of cueing. Cue-target interval analysis revealed two main effects paralleling behavior. First, a typical contingent negative variation (CNV), induced by the cue and resolved immediately after target onset, was found larger for temporal attention cueing than for spatial and motor response cueing. Second, a posterior and late cue-P3 complex showed the reverse profile. Analyses of lateralized readiness potentials (LRP) revealed both patterns of motor response inhibition and activation. Taken together these results help to clarify and disentangle the respective effects of temporal attention on the one hand, and of the combination of spatial attention and motor response preparation on the other hand on brain activity and behavior.

PurposePrevention of multidrug resistant (MDR) bacterial contamination remains a major challenge in ICUs. Many hospital outbreaks involving MDR transmitted through environmental contamination have been reported. Bedside high-density EEG allow for dynamic cognitive evaluation in brain-injured patients and is used more and more frequently in clinical practice to evaluate brain function and predict outcome in severely neurologically impaired patients. Unfortunately, the material used for this procedure is not entirely disposable.MethodWe performed a systematic analysis of MDR bacterial contamination in patients contaminated in our ICU using specific bacteriological methods.ResultsWe report a proven case of cross-contamination of an extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae strain, and a possible case of cross-contamination of a carbapenem-resistant Acinetobacter baumannii strain.ConclusionCross-contamination of MDR bacteria is possible through high-density EEG material. However, appropriate procedures can decrease this risk.