Is oral feeding compatible with an unresponsive wakefulness syndrome?

Swallowing Assessment in Post-Comatose Patients: A Feasibility Study on the SWADOC Tool

Background: After a severe brain injury and a coma, patients may develop disorders of consciousness (DoC), frequently accompanied by severe dysphagia. The evaluation and therapy of swallowing are therefore essential aspects of their management. Objectives: This study aims to evaluate the SWallowing Assessment in Disorders of Consciousness (SWADOC) tool in the assessment of swallowing in post-comatose patients. Here, we validate its quantitative items, describe preliminary results and identify limitations. Methods: Fourteen post-comatose patients were repeatedly evaluated with the Simplified Evaluation of CONsciousness Disorders (SECONDs) and with the SWADOC. Results: The internal consistency of the oral and pharyngeal subscales of the SWADOC was good. The test-retest reliability showed that all items, all subscores and the total score were stable except for two items (endo-buccal secretions and bronchial congestion). A comparison to the Facial Oral Tract Therapy Swallowing Assessment of Saliva (F.O.T.T-SAS) confirmed that scoring with the SWADOC offers a greater potential for quantitative observations in assessing swallowing abilities among patients with DoC. The SECONDs scores and SWADOC total scores showed a significant positive correlation (τ = 0.78, p < 0.001). Conclusions: This study provides preliminary but encouraging results on the psychometric properties of the SWADOC tool. It shows that this tool is relevant and feasible as a bedside assessment of dysphagia in patients with DoC.

Swallowing dysfunctions in patients with disorders of consciousness: Evidence from neuroimaging data, assessment, and management

Following severe brain injuries, a subset of patients may remain in an altered state of consciousness; most of these patients require artificial feeding. Currently, a functional oral phase and the presence of exclusive oral feeding may constitute signs of consciousness. Additionally, the presence of pharyngo-laryngeal secretions, saliva aspiration, cough reflex and tracheostomy are related to the level of consciousness. However, the link between swallowing and consciousness is yet to be fully understood. The primary aim of this review is to establish a comprehensive overview of the relationship between an individual's conscious behaviour and swallowing (reflexive and voluntary). Previous studies of brain activation during volitional and non-volitional swallowing tasks in healthy subjects are also reviewed. We demonstrate that the areas activated by voluntary swallowing tasks (primary sensorimotor, cingulate, insula, premotor, supplementary motor, cerebellum, and operculum) are not specific to deglutitive function but are shared with other motor tasks and brain networks involved in consciousness. This review also outlines suitable assessment and treatment methods for dysphagic patients with disorders of consciousness. Finally, we propose that markers of swallowing could contribute to the development of novel diagnostic guidelines for patients with disorders of consciousness.

The relationship between neurogenic dysphagia, stroke-associated pneumonia and functional outcome in a cohort of ischemic stroke patients treated with mechanical thrombectomy

INTRODUCTION

Mechanical thrombectomy (MT) is an established treatment approach in acute ischemic stroke patients with large vessel occlusion (LVO). Recent studies suggest that the prevalence of dysphagia and pneumonia risk is increased in this patient population. The aim of this study was to systematically evaluate the prevalence, predictors, and influence of neurogenic dysphagia for 3-month outcome in a large population of patients receiving MT and to elucidate the relationship between dysphagia, stroke-associated pneumonia (SAP) and medium-term functional outcome.

MATERIALS AND METHODS

Data of a prospective collected registry of patients with LVO and MT between 2016 and 2019 were analyzed retrospectively. Binary logistic regression was carried out to determine predictors for dysphagia and 3-month outcome as measured by the modified Rankin Scale, respectively. A mediation analysis was performed to investigate the mediating influence of intercurrent SAP.

RESULTS

A total of 567 patients were included in the study. Mean age was 73.4 years, 47.8% of the patients were female, and median NIHSS was 15.0. The prevalence of dysphagia was 75.1% and 23.3% of all patients developed SAP. In the regression analysis, dysphagia was one of the main independent predictors for poor functional outcome at 3 months. The mediator analysis revealed that the effect of dysphagia on the functional outcome at 3 months was not mediated by the occurrence of SAP.

DISCUSSION

The prevalence of dysphagia is high and exerts both negative short- and medium-term effects on patients with large vessel occlusion who undergo MT.

Predictors of long-term decannulation in patients with disorders of consciousness

Purpose

The predictors of tracheostomy decannulation in patients with disorders of consciousness (DOC) are not comprehensively understood, making prognosis difficult. The primary objective of this study was to identify predictors of tracheostomy decannulation in patients with disorders of consciousness (DOC). The secondary aim was to evaluate the feasibility and safety of the modified Evans blue dye test (MEBDT) in tracheostomized DOC patients.

Methods

This retrospective study included all patients with disorders of consciousness (DOC) who underwent tracheostomy and were admitted between January 2016 and September 2022. Age, sex, etiology, initial Glasgow coma scale (GCS), initial Coma Recovery Scale-Revised (CRS-R), diagnosis of unresponsive wakefulness syndrome (UWS) or minimal consciousness state (MCS), MEBDT, initial modified Rankin scale (mRS), and initial Functional Oral Intake Scale (FOIS) were collected upon study enrollment. The relationship between clinical characteristics and cannulation status was investigated through a Cox regression model.

Results

A total of 141 patients were included in the study. The average age of these patients was 52.5 ± 16.7 years, with 42 (29.8%) being women. During the study period, 86 subjects (61%) underwent successful decannulation. Univariate analysis revealed that decannulated patients exhibited a significantly better conscious state compared to those without decannulation (CRS-R: p < 0.001; GCS: p = 0.023; MCS vs. UWS: p < 0.001). Additionally, a negative modified Evans blue dye test (MEBDT) result was significantly associated with tracheostomy decannulation (p < 0.001). In the multivariate analysis, successful decannulation was associated with a higher level of consciousness (MCS vs. UWS, p < 0.001, HR = 6.694) and a negative MEBDT result (negative vs. positive, p = 0.006, HR = 1.873). The Kaplan-Meier analysis further demonstrated that MEBDT-negative patients and those in the MCS category had a higher probability of decannulation at 12 months (p < 0.001).

Conclusion

The findings of this study indicate that a negative MEBDT result and a higher level of consciousness can serve as predictive factors for successful tracheostomy decannulation in DOC patients.

Feeding modality evolution in traumatic brain injury patients with severe alteration of consciousness: A observational study

The aim of this study was to compare feeding modalities and the level of consciousness in patients with a severe brain injury during reeducation and rehabilitation. The clinical data of vegetative state or minimal conscious state due to severe traumatic brain injury hospitalized in a coma arousal unit were collected from 2012 to 2019. Feeding modalities were evaluated clinically and with functional endoscopy evaluation of swallowing or video fluoroscopy and functional oral intake scale. Evolution of consciousness was evaluated using Wessex Head Injury Matrix scale (WHIM). Comparison between WHIM score and feeding modalities were performed at admission and at discharge of the arousal unit. Of the 93 patients considered, 33 were included corresponding to inclusion criteria (traumatic brain injury, disorder of consciousness and age > 18 years). The mean age was 44.8 ± 16.8 years, and there were 6 females for 27 males. At admission, all patients were fed by gastrostomy (n = 25) or by nasogastric tube (n = 8) and 27 had a tracheostomy. At discharge, 10 patients keep an exclusive alimentation by gastrostomy (Group 1, G1) as 23 had exclusive oral feeding (Group 2, G2). The score of the WHIM at admission was identical in both groups (21.7 ± 10.9 (G1) vs. 21.0 ± 15.33 (G2) (ns)). At discharge, WHIM increased to 38.3 ± 15.4 in G1 and to 49.8 ± 9.7 in G2 (P < .05). WHIM score was significantly higher in G2 than in G1 (P < .05). There was a positive correlation between functional oral intake scale and WHIM at discharge. Our results demonstrated that recovery of oral feeding in patients with a severe traumatic brain injury appeared in those who had the better improvement of consciousness level.

Feasibility study of the Nox-T3 device to detect swallowing and respiration pattern in neurologically impaired patients in the acute phase

Dysphagia is a frequent complication in neurologically impaired patients, which can lead to aspiration pneumonia and thus prolonged hospitalization or even death. It is essential therefore, to detect and assess dysphagia early for best patient care. Fiberoptic endoscopic and Videofluoroscopy evaluation of swallowing are the gold standard exams in swallowing studies but neither are perfectly suitable for patients with disorders of consciousness (DOC). In this study, we aimed to find the sensitivity and specificity of the Nox-T3 sleep monitor for detection of swallowing. A combination of submental and peri-laryngeal surface electromyography, nasal cannulas and respiratory inductance plethysmography belts connected to Nox-T 3 allows recording swallowing events and their coordination with breathing, providing time-coordinated patterns of muscular and respiratory activity. We compared Nox-T3 swallowing capture to manual swallowing detection on fourteen DOC patients. The Nox-T3 method identified swallow events with a sensitivity of 95% and a specificity of 99%. In addition, Nox-T3 has qualitative contributions, such as visualization of the swallowing apnea in the respiratory cycle which provide additional information on the swallowing act that is useful to clinicians in the management and rehabilitation of the patient. These results suggest that Nox-T3 could be used for swallowing detection in DOC patients and support its continued clinical use for swallowing disorder investigation.

Links Between Swallowing and Consciousness: A Narrative Review

This literature review explores a wide range of themes addressing the links between swallowing and consciousness. Signs of consciousness are historically based on the principle of differentiating reflexive from volitional behaviors. We show that the sequencing of the components of swallowing falls on a continuum of voluntary to reflex behaviors and we describe several types of volitional and non-volitional swallowing tasks. The frequency, speed of initiation of the swallowing reflex, efficacy of the pharyngeal phase of swallowing and coordination between respiration and swallowing are influenced by the level of consciousness during non-pathological modifications of consciousness such as sleep and general anesthesia. In patients with severe brain injury, the level of consciousness is associated with several components related to swallowing, such as the possibility of extubation, risk of pneumonia, type of feeding or components directly related to swallowing such as oral or pharyngeal abnormalities. Based on our theoretical and empirical analysis, the efficacy of the oral phase and the ability to receive exclusive oral feeding seem to be the most robust signs of consciousness related to swallowing in patients with disorders of consciousness. Components of the pharyngeal phase (in terms of abilities of saliva management) and evoked cough may be influenced by consciousness, but further studies are necessary to determine if they constitute signs of consciousness as such or only cortically mediated behaviors. This review also highlights the critical lack of tools and techniques to assess and treat dysphagia in patients with disorders of consciousness.

Understanding, detecting, and stimulating consciousness recovery in the ICU

Coma is a medical and socioeconomic emergency. Although underfunded, research on coma and disorders of consciousness has made impressive progress. Lesion-network-mapping studies have delineated the precise brainstem regions that consistently produce coma when damaged. Functional neuroimaging has revealed how mechanisms like "communication through coherence" and "inhibition by gating" work in synergy to enable cortico-cortical processing and how this information transfer is disrupted in brain injury. On the cellular level, break-down of intracellular communication between the layer 5 pyramidal cell soma and the apical dendritic part impairs dendritic information integration, with up-stream effects on microcircuits in local neuronal populations and on large-scale fronto-parietal networks, which correlates with loss of consciousness. A breakthrough in clinical concepts occurred when fMRI, and later EEG, studies revealed that 15% of clinically unresponsive patients in acute and chronic settings are in fact awake and aware, as shown by their command following abilities revealed by brain activation during motor and locomotion imagery tasks. This condition is now termed "cognitive motor dissociation." Furthermore, epidemiological data on coma were literally non-existent until recently because of difficulties related to case ascertainment with traditional methods, but crowdsourcing of family observations enabled the first estimates of how frequent coma is in the general population (pooled annual incidence of 201 coma cases per 100,000 population in the UK and the USA). Diagnostic guidelines on coma and disorders of consciousness by the American Academy of Neurology and the European Academy of Neurology provide ambitious clinical frameworks to accommodate these achievements. As for therapy, a broad range of medical and non-medical treatment options is now being tested in increasingly larger trials; in particular, amantadine and transcranial direct current stimulation appear promising in this regard. Major international initiatives like the Curing Coma Campaign aim to raise awareness for coma and disorders of consciousness in the public, with the ultimate goal to make more brain-injured patients recover consciousness after a coma. To highlight all these accomplishments, this paper provides a comprehensive overview of recent progress and future challenges related to understanding, detecting, and stimulating consciousness recovery in the ICU.

Neurogenic Dysphagia and Nutrition in Disorder of Consciousness: An Overview with Practical Advices on an "Old" but Still Actual Clinical Problem

Neurogenic dysphagia is a difficulty in swallowing food caused by disease or impairment of the nervous system, including stroke and traumatic brain injury. The most clinically apparent complication of neurogenic dysphagia is pulmonary aspiration, which may manifest itself acutely as choking or coughing, respiratory distress, wheezing, gasping or gurgling, and tachycardia. However, chronic symptoms, including weight loss, production of excessive oral secretions and aspiration pneumonia, may be also present, especially in patients with a disorder of consciousness (DOC). Usually, patients with dysphagia after the acute phase need to be treated with enteral nutrition using a feeding tube. This avoids patient malnutrition and supports the rehabilitation program. This narrative review aims to investigate dysphagia and its complications and management in patients with DOC. Clinical indications and practical advice on how to assess and treat this complex problem are also provided.

A Precision Medicine Framework for Classifying Patients with Disorders of Consciousness: Advanced Classification of Consciousness Endotypes (ACCESS)

BACKGROUND

Consciousness in patients with brain injury is traditionally assessed based on semiological evaluation at the bedside. This classification is limited because of low granularity, ill-defined and rigid nomenclatures incompatible with the highly fluctuating nature of consciousness, failure to identify specific brain states like cognitive motor dissociation, and neglect for underlying biological mechanisms. Here, the authors present a pragmatic framework based on consciousness endotypes that combines clinical phenomenology with all essential physiological and biological data, emphasizing recovery trajectories, therapeutic potentials and clinical feasibility.

METHODS

The Neurocritical Care Society's Curing Coma Campaign identified an international group of experts who convened in a series of online meetings between May and November 2020 to discuss and propose a novel framework for classifying consciousness.

RESULTS

The expert group proposes Advanced Classification of Consciousness Endotypes (ACCESS), a tiered multidimensional framework reflecting increasing complexity and an aspiration to consider emerging and future approaches. Tier 1 is based on clinical phenotypes and structural imaging. Tier 2 adds functional measures including EEG, PET and functional MRI, that can be summarized using the Arousal, Volition, Cognition and Mechanisms (AVCM) score (where "Volition" signifies volitional motor responses). Finally, Tier 3 reflects dynamic changes over time with a (theoretically infinite) number of physiologically distinct states to outline consciousness recovery and identify opportunities for therapeutic interventions.

CONCLUSIONS

Whereas Tiers 1 and 2 propose an approach for low-resource settings and state-of-the-art expertise at leading academic centers, respectively, Tier 3 is a visionary multidimensional consciousness paradigm driven by continuous incorporation of new knowledge while addressing the Curing Coma Campaign's aspirational goals.

Feasibility and Safety of Fiberoptic Endoscopic Evaluation of Swallowing in People with Disorder of Consciousness: A Systematic Review

People with disorders of consciousness (DoC) often receive nutrition via a feeding tube and the swallowing ability in this population is not fully understood. In particular, fiberoptic endoscopic evaluation of swallowing (FEES) with people with DoC requires further investigation. The aim of this systematic review is to collate, assess and summarise the current evidence of whether FEES is feasible and safe with people with DoC. Multiple health databases were searched in November 2019 to identify studies which used FEES with people with DoC. Data extraction included demographic information, adverse events reported and outcomes related to oral feeding. The Diagnostic Accuracy Quality Scale (DAQS) was used to assess the quality of the studies. In total only four studies were found, all of which had a high risk of bias. Many participants went from nil by mouth to some degree of oral diet sometime after the FEES was completed with low reporting of adverse events associated with FEES. This suggests a potential for the use of FEES in people with DoC. However, the evidence is low and further studies are recommended to improve understanding of FEES with people with DoC. Recommendations for clinical practice and areas for future research are outlined.

The Development and Validation of the SWADOC: A Study Protocol for a Multicenter Prospective Cohort Study

Background: After a coma, patients with severe brain injury may present disorders of consciousness (DOC). A substantial proportion of these patients also suffer from severe dysphagia. Assessment of and therapy for swallowing disabilities of patients with DOC are essential because dysphagia has major functional consequences and comorbidities. Dysphagia evaluation in patients with DOC is impeded by the lack of adapted tools. The first aim of this study was to create a new tool, the SWallowing Assessment in Disorders Of Consciousness (SWADOC), and propose a validation protocol. The SWADOC was developed to help therapists assess factors related to swallowing in patients with DOC. The second aim was to investigate the relationship between patients' level of consciousness and SWADOC items and scores. Method/Design: In this multicenter prospective cohort, 104 patients with DOC will be tested three times over five consecutive days with the SWADOC. Statistical analyses will focus on the reliability and validity of the SWADOC, especially the intrarater and interrater reliability, internal consistency, measures of dispersion, and concurrent validity with the Facial Oral Tract Therapy Swallowing Assessment of Saliva (FOTT-SAS). The level of consciousness will be assessed with the Simplified Evaluation of CONsciousness Disorders (SECONDs) and the Coma Recovery Scale-Revised (CRS-R). Discussion: The assessment of swallowing abilities among patients with DOC is the first necessary step toward the development of a customized dysphagia care plan. A validated scoring tool will be essential for clinicians to better assess dysphagia in patients with DOC and document the evolution of their disorders. Trial Registration: NCT04706689.

Nursing, Caregiving and Psychological support in Chronic Disorders of Consciousness: a scoping review

BACKGROUND AND AIMS

The major disorders of consciousness include Coma, Vegetative State, and Minimally Conscious State. The care and the management of patients with Disorders of Consciousness (DOC) have raised several important ethical, social and medical issues. Aim of this review is to evaluate the role of nursing and psychological support in DOC management, in order to improve the quality of life of both patients and their caregivers.

METHODS

Studies dealing with DOC, nursing and caregiving pubblished in the last 20 years (from January 2000 to June 2020) were identified by searching on PubMed, Web of Science and Cochrane databases.

RESULTS

This review highlights the important role of DOC carevigers in the complex management of these frail patients, as well as the need for a specific support and counselling of caregivers. This psychological support may be given by nurses, as they are the healthcare professionals more involved in DOC care and cure.

DISCUSSION

Over the last years, specific recommendations for the assessment and rehabilitation of patients with DOC have been promulgated by neurorehabilitation organizations to provide some guidelines for the care and cure of such frail patients. Indeed, DOC patients need a multidisciplinary approach in which both caregivers and nurses have a pivotal role.

CONCLUSIONS

As the family is a critical and fundamental aspect in the management of DOC patients, it should be considered an integral part of care in the future guidelines.

Auditory localization should be considered as a sign of minimally conscious state based on multimodal findings

Auditory localization (i.e. turning the head and/or the eyes towards an auditory stimulus) is often part of the clinical evaluation of patients recovering from coma. The objective of this study is to determine whether auditory localization could be considered as a new sign of minimally conscious state, using a multimodal approach. The presence of auditory localization and the clinical outcome at 2 years of follow-up were evaluated in 186 patients with severe brain injury, including 64 with unresponsive wakefulness syndrome, 28 in minimally conscious state minus, 71 in minimally conscious state plus and 23 who emerged from the minimally conscious state. Brain metabolism, functional connectivity and graph theory measures were investigated by means of ¹⁸F-fluorodeoxyglucose positron emission tomography, functional MRI and high-density electroencephalography in two subgroups of unresponsive patients, with and without auditory localization. These two subgroups were also compared to a subgroup of patients in minimally conscious state minus. Auditory localization was observed in 13% of unresponsive patients, 46% of patients in minimally conscious state minus, 62% of patients in minimally conscious state plus and 78% of patients who emerged from the minimally conscious state. The probability to observe an auditory localization increased along with the level of consciousness, and the presence of auditory localization could predict the level of consciousness. Patients with auditory localization had higher survival rates (at 2-year follow-up) than those without localization. Differences in brain function were found between unresponsive patients with and without auditory localization. Higher connectivity in unresponsive patients with auditory localization was measured between the fronto-parietal network and secondary visual areas, and in the alpha band electroencephalography network. Moreover, patients in minimally conscious state minus significantly differed from unresponsive patients without auditory localization in terms of brain metabolism and alpha network centrality, whereas no difference was found with unresponsive patients who presented auditory localization. Our multimodal findings suggest differences in brain function between unresponsive patients with and without auditory localization, which support our hypothesis that auditory localization should be considered as a new sign of minimally conscious state. Unresponsive patients showing auditory localization should therefore no longer be considered unresponsive but minimally conscious. This would have crucial consequences on these patients’ lives as it would directly impact the therapeutic orientation or end-of-life decisions usually taken based on the diagnosis.

Decannulation and improvement of responsiveness in patients with disorders of consciousness

Decannulation is a rehabilitation milestone in patients with Disorders of Consciousness (DoC). investigate the relationship between decannulation and improvement of responsiveness (IR) in DoC. 236 tracheostomized patients with severe Acquired Brain Injury and DoC admitted in the Intensive Rehabilitation Unit were retrospectively included. They received personalized interdisciplinary rehabilitation. At discharge, IR was evaluated. The association between IR and demographic/clinical data was investigated using a logistic regression analysis, both in the Unresponsive Wakefulness Syndrome (UWS) and Minimal Consciousness State (MCS) group, divided according to their Coma Recovery Scale-Revised score at admission. In the UWS group (N = 107), only decannulation was associated with IR at discharge (OR: 5.94, CI: 2.08-16.91, p = .001). In the MCS group (N = 129) time post-injury (OR: 0.983, CI: 0.97-0.99, p = .012) and decannulation were associated with IR at discharge (OR: 17.9, CI: 6.39-50.13, p < .001). Decannulation and IR were found to be strongly related, independently from the initial clinical state. While the retrospective nature of the study could not exclude that decannulation may be a consequence of a spontaneous recovery, the obtained results may disclose its potential influence on the clinical history of patients with DoC.

Swallowing in individuals with disorders of consciousness: A cohort study

BACKGROUND

After a period of coma, a proportion of individuals with severe brain injury remain in an altered state of consciousness before regaining partial or complete recovery. Individuals with disorders of consciousness (DOC) classically receive hydration and nutrition through an enteral-feeding tube. However, the real impact of the level of consciousness on an individual's swallowing ability remains poorly investigated.

OBJECTIVE

We aimed to document the incidence and characteristics of dysphagia in DOC individuals and to evaluate the link between different components of swallowing and the level of consciousness.

METHODS

We analyzed clinical data on the respiratory status, oral feeding and otolaryngologic examination of swallowing in DOC individuals. We analyzed the association of components of swallowing and participant groups (i.e., unresponsive wakefulness syndrome [UWS] and minimally conscious state [MCS]).

RESULTS

We included 92 individuals with DOC (26 UWS and 66 MCS). Overall, 99% of the participants showed deficits in the oral and/or pharyngeal phase of swallowing. As compared with the MCS group, the UWS group more frequently had a tracheostomy (69% vs 24%), with diminished cough reflex (27% vs 54%) and no effective oral phase (0% vs 21%).

CONCLUSION

Almost all DOC participants had severe dysphagia. Some components of swallowing (i.e., tracheostomy, cough reflex and efficacy of the oral phase of swallowing) were related to consciousness. In particular, no UWS participant had an efficient oral phase, which suggests that its presence may be a sign of consciousness. In addition, no UWS participant could be fed entirely orally, whereas no MCS participant orally received ordinary food. Our study also confirms that objective swallowing assessment can be successfully completed in DOC individuals and that specific care is needed to treat severe dysphagia in DOC.

Joint Neuropsychological Assessment through Coma/Near Coma and Level of Cognitive Functioning Assessment Scales Reduces Negative Findings in Pediatric Disorders of Consciousness

The present study aimed to: (a) characterize the emergence to a conscious state (CS) in a sample of children and adolescents with severe brain injury during the post-acute rehabilitation and through two different neuropsychological assessment tools: the Rappaport Coma/Near Coma Scale (CNCS) and Level of Cognitive Functioning Assessment Scale (LOCFAS); (b) compare the evolution in patients with brain lesions due to traumatic and non-traumatic etiologies; and (c) describe the relationship between the emergence to a CS and some relevant clinical variables. In this observational prospective longitudinal study, 92 consecutive patients were recruited. Inclusion criteria were severe disorders of consciousness (DOC), Glasgow Coma Scale (GCS) score ≤8 at insult, age 0 to 18 years, and direct admission to inpatient rehabilitation from acute care. The main outcome measures were CNCS and LOCFAS, both administered three and six months after injury. The cohort globally shifted towards milder DOC over time, moving from overall 'moderate/near coma' at three months to 'near/no coma' at six months post-injury. The shift was captured by both CNCS and LOCFAS. CNCS differentiated levels of coma at best, while LOCFAS was superior in characterizing the emergence from coma. Agreement between scales was fair, and reduced negative findings at less than 10%. Patients with traumatic brain injury (TBI) vs. non-traumatic brain injury (NTBI) were older and had neurosurgical intervention more frequently. No relation between age and the level of consciousness was found overall. Concurrent administration of CNCS and LOCFAS reduced the rate of false negatives and better detected signs of arousal and awareness. This provides indication to administer both tools to increase measurement precision.

European Academy of Neurology guideline on the diagnosis of coma and other disorders of consciousness

BACKGROUND AND PURPOSE

Patients with acquired brain injury and acute or prolonged disorders of consciousness (DoC) are challenging. Evidence to support diagnostic decisions on coma and other DoC is limited but accumulating. This guideline provides the state-of-the-art evidence regarding the diagnosis of DoC, summarizing data from bedside examination techniques, functional neuroimaging and electroencephalography (EEG).

METHODS

Sixteen members of the European Academy of Neurology (EAN) Scientific Panel on Coma and Chronic Disorders of Consciousness, representing 10 European countries, reviewed the scientific evidence for the evaluation of coma and other DoC using standard bibliographic measures. Recommendations followed the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. The guideline was endorsed by the EAN.

RESULTS

Besides a comprehensive neurological examination, the following suggestions are made: probe for voluntary eye movements using a mirror; repeat clinical assessments in the subacute and chronic setting, using the Coma Recovery Scale - Revised; use the Full Outline of Unresponsiveness score instead of the Glasgow Coma Scale in the acute setting; obtain clinical standard EEG; search for sleep patterns on EEG, particularly rapid eye movement sleep and slow-wave sleep; and, whenever feasible, consider positron emission tomography, resting state functional magnetic resonance imaging (fMRI), active fMRI or EEG paradigms and quantitative analysis of high-density EEG to complement behavioral assessment in patients without command following at the bedside.

CONCLUSIONS

Standardized clinical evaluation, EEG-based techniques and functional neuroimaging should be integrated for multimodal evaluation of patients with DoC. The state of consciousness should be classified according to the highest level revealed by any of these three approaches.