Unconsciousness or unresponsiveness in akinetic mutism? Insights from a multimodal longitudinal exploration.

The clinical assessment of patients with disorders of consciousness (DoC) relies on the observation of behavioural responses to standardised sensory stimulation. However, several medical comorbidities may directly impair the production of reproducible and appropriate responses, thus reducing the sensitivity of behaviour-based diagnoses. One such comorbidity is akinetic mutism (AM), a rare neurological syndrome characterised by the inability to initiate volitional motor responses, sometimes associated with clinical presentations that overlap with those of DoC. In this paper, we describe the case of a patient with large bilateral mesial frontal lesions, showing prolonged behavioural unresponsiveness and severe disorganisation of electroencephalographic (EEG) background, compatible with a vegetative state/unresponsive wakefulness syndrome (VS/UWS). By applying an unprecedented multimodal battery of advanced imaging and electrophysiology-based techniques (AIE) encompassing spontaneous EEG, evoked potentials, event-related potentials, transcranial magnetic stimulation combined with EEG and structural and functional MRI, we provide the following: (i) a demonstration of the preservation of consciousness despite unresponsiveness in the context of AM, (ii) a plausible neurophysiological explanation for behavioural unresponsiveness and its subsequent recovery during rehabilitation stay and (iii) novel insights into the relationships between DoC, AM and parkinsonism. The present case offers proof-of-principle evidence supporting the clinical utility of a multimodal hierarchical workflow that combines AIEs to detect covert signs of consciousness in unresponsive patients.

Common Data Elements for Disorders of Consciousness: Recommendations from the Working Group in the Pediatric Population.

BACKGROUND: The fundamental gap obstructing forward progress of evidenced-based care in pediatric and neonatal disorders of consciousness (DoC) is the lack of defining consensus-based terminology to perform comparative research. This lack of shared nomenclature in pediatric DoC stems from the inherently recursive dilemma of the inability to reliably measure consciousness in the very young. However, recent advancements in validated clinical examinations and technologically sophisticated biomarkers of brain activity linked to future abilities are unlocking this previously formidable challenge to understanding the DoC in the developing brain. METHODS: To address this need, the first of its kind international convergence of an interdisciplinary team of pediatric DoC experts was organized by the Neurocritical Care Society's Curing Coma Campaign. The multidisciplinary panel of pediatric DoC experts proposed pediatric-tailored common data elements (CDEs) covering each of the CDE working groups including behavioral phenotyping, biospecimens, electrophysiology, family and goals of care, neuroimaging, outcome and endpoints, physiology and big Data, therapies, and pediatrics. RESULTS: We report the working groups' pediatric-focused DoC CDE recommendations and disseminate CDEs to be used in studies of pediatric patients with DoC. CONCLUSIONS: The CDEs recommended support the vision of progressing collaborative and successful internationally collaborative pediatric coma research.

[Neuromodulatory pharmacotherapy individualization in prolonged and chronic consciousness disorders after severe traumatic brain injury]. / K probleme individualizatsii neiromodulyatornoi farmakoterapii pri prolongirovannykh i khronicheskikh narusheniyakh soznaniya vsledstvie tyazheloi cherepno-mozgovoi travmy.

One of the most probable causes of effective therapy for post-comatose disorders of consciousness is the lack of individualization of drug prescriptions. In this observational study, we analyzed 48 courses of neuromodulatory therapy in 28 patients with prolonged and chronic disorders of consciousness following severe traumatic brain injury. Comparison of 24 effective and 24 ineffective courses demonstrated higher effectiveness of pharmacotherapy through its individualization, i.e. the choice of a drug whose neuromodulatory spectrum would correspond to neurological syndromes of neurotransmitter dysfunction. In this approach, 74% of therapy courses were effective while opposite management resulted only 34% of effective courses.

Prediction of voluntary movements of the upper extremities by resting state-brain regional glucose metabolism in patients with chronic severe brain injury: A pilot study.

Confirmation of the exact voluntary movements of patients with disorder of consciousness following severe traumatic brain injury (TBI) is difficult because of the associated communication disturbances. In this pilot study, we investigated whether regional brain glucose metabolism assessed by 18 F-fluorodeoxyglucose positron emission tomography (FDG-PET) at rest could predict voluntary movement in severe TBI patients, particularly those with sufficient upper limb capacity to use communication devices. We visually and verbally instructed patients to clasp or open their hands. After video capture, three independent rehabilitation therapists determined whether the patients' movements were voluntary or involuntary. The results were compared with the standardized uptake value in the primary motor cortex, referring to the Penfield's homunculus, by resting state by FDG-PET imaged 1 year prior. Results showed that glucose uptake in the left (p = 0.0015) and right (p = 0.0121) proximal limb of the primary motor cortex, based on Penfield's homunculus on cerebral cartography, may reflect contralateral voluntary movement. Receiver operating characteristic curve analysis showed that a mean cutoff standardized uptake value of 5.47 ± 0.08 provided the best sensitivity and specificity for differentiating between voluntary and involuntary movements in each area. FDG-PET may be a useful and robust biomarker for predicting long-term recovery of motor function in severe TBI patients with disorders of consciousness.

Effect of non-invasive brain stimulation on conscious disorder in patients after brain injury: a network meta-analysis.

OBJECTIVE: To systematically evaluate the rehabilitation effect of non-invasive brain stimulation (NIBS) on disorder of consciousness (DOC) after brain injury and compare the effects of different NIBSs. METHODS: Randomized controlled trials (RCTs) on the effect of NIBS on DOC after brain injury were retrieved from the PubMed, Cochrane Library, Web of Science, CNKI, VIP, Wanfang Data, and CBM databases from inception to October 2022. The risk of bias and quality of the trials were assessed following the Cochrane Handbook of Systematic Reviews and the physiotherapy evidence database Jadad Scale. Statistical analysis was conducted with RevMan 5.4 and R Studio. This study was registered on PROSPERO (No. CRD42022371334). RESULTS: A total of 28 articles were included involving 1118 patients. Meta-analysis showed that NIBS combined with routine rehabilitation had the highest effect than the routine rehabilitation and the sham NIBS combined with routine rehabilitation. The cumulative probability ranking results showed that the rTMS was best. The order of network meta-analysis with GCS (Glasgow Coma Scale) as the outcome index is rTMS combined with routine rehabilitation > tDCS combined with routine rehabilitation > routine rehabilitation > NIBS sham stimulation combined with routine rehabilitation. The order of network meta-analysis with CRS-R (Coma Recovery Scale-Revised) as the outcome index is rTMS combined with routine rehabilitation > tDCS combined with routine rehabilitation > NIBS sham stimulation combined with routine rehabilitation > routine rehabilitation. For patients with different conditions of DOC, the subgroup analysis results showed that rTMS improved the effect of patients with severe DOC better than those with unclear conditions of DOC, but the overall results of the two groups were not significantly different. On the contrary, the effect of tDCS on patients with DOC whose condition was not clear was better than that on patients with severe DOC, and the effect on patients with severe DOC was not significant (P > 0.05). In terms of safety, only 9 articles mentioned ADRs in the included literature, including 8 articles without ADRs, and 1 article with ADRs. CONCLUSION: Based on the research results of various indicators, NIBS can improve DOC after brain injury, and the rTMS is the best. Limited by the number and the quality of literature, the above conclusions need more high-quality research to verify.

Description and Outcome of Severe Hypoglycemic Encephalopathy in the Intensive Care Unit.

BACKGROUND: Disorders of consciousness due to severe hypoglycemia are rare but challenging to treat. The aim of this retrospective cohort study was to describe our multimodal neurological assessment of patients with hypoglycemic encephalopathy hospitalized in the intensive care unit and their neurological outcomes. METHODS: Consecutive patients with disorders of consciousness related to hypoglycemia admitted for neuroprognostication from 2010 to 2020 were included. Multimodal neurological assessment included electroencephalography, somatosensory and cognitive event-related potentials, and morphological and quantitative magnetic resonance imaging (MRI) with quantification of fractional anisotropy. Neurological outcomes at 28 days, 3 months, 6 months, 1 year, and 2 years after hypoglycemia were retrieved. RESULTS: Twenty patients were included. After 2 years, 75% of patients had died, 5% remained in a permanent vegetative state, 10% were in a minimally conscious state, and 10% were conscious but with severe disabilities (Glasgow Outcome Scale-Extended scores 3 and 4). All patients showed pathologic electroencephalography findings with heterogenous patterns. Morphological brain MRI revealed abnormalities in 95% of patients, with various localizations including cortical atrophy in 65% of patients. When performed, quantitative MRI showed decreased fractional anisotropy affecting widespread white matter tracts in all patients. CONCLUSIONS: The overall prognosis of patients with severe hypoglycemic encephalopathy was poor, with only a small fraction of patients who slowly improved after intensive care unit discharge. Of note, patients who did not improve during the first 6 months did not recover consciousness. This study suggests that a multimodal approach capitalizing on advanced brain imaging and bedside electrophysiology techniques could improve diagnostic and prognostic performance in severe hypoglycemic encephalopathy.

Establishment and evaluation of a prediction model for acute gastrointestinal injury in patients with prolonged disorder of consciousness.

OBJECTIVE: To establish a prediction model for acute gastrointestinal injury (AGI) in patients with prolonged disorder of consciousness (pDOC) and to evaluate and apply the prediction model.  METHODS: The clinical data of 165 patients with pDOC admitted to the hyperbaric oxygen department from January 2021 to December 2021 were retrospectively reviewed, and the patients were divided into an AGI group (n = 91) and an N-AGI group (n = 74) according to whether AGI occurred. A prediction model was built by fitting multiple independent influencing factors through logistic regression. The receiver operating characteristic (ROC) curve was used to evaluate the predictive value of the model, the Hosmer-Lemeshow (H-L) test was used to evaluate the goodness-of-fit of the model, and the ROC curve and calibration curve were drawn to evaluate the predictive performance. A nomogram was plotted to visualize the prediction model. RESULTS: According to the multivariate logistic regression analysis results, the prediction model was finally constructed with the CRS-R score, DAO, PCT, ALB, and I-FABP, and a nomogram was generated. The area under the ROC curve (AUC) of the prediction model was 0.931, the sensitivity was 83.5%, and the specificity was 93.2%. The data were divided into 5 groups for the H-L test (χ2 = 2.54, P = 0.468 > 0.05) and into 10 groups for the H-L test (χ2 = 9.98, P = 0.267 > 0.05). A calibration curve was drawn based on the test results, indicating that the prediction model has a good goodness-of-fit and good prediction stability. CONCLUSION: The prediction model for AGI in pDOC patients constructed in this study can be used in clinical practice and is helpful to predict the occurrence of AGI in pDOC patients.

Spontaneous transient brain states in EEG source space in disorders of consciousness.

Spontaneous transient states were recently identified by functional magnetic resonance imaging and magnetoencephalography in healthy subjects. They organize and coordinate neural activity in brain networks. How spontaneous transient states are altered in abnormal brain conditions is unknown. Here, we conducted a transient state analysis on resting-state electroencephalography (EEG) source space and developed a state transfer analysis to patients with disorders of consciousness (DOC). They uncovered different neural coordination patterns, including spatial power patterns, temporal dynamics, spectral shifts, and connectivity construction varies at potentially very fast (millisecond) time scales, in groups with different consciousness levels: healthy subjects, patients in minimally conscious state (MCS), and patients with vegetative state/unresponsive wakefulness syndrome (VS/UWS). Machine learning based on transient state features reveal high classification accuracy between MCS and VS/UWS. This study developed methodology of transient states analysis on EEG source space and abnormal brain conditions. Findings correlate spontaneous transient states with human consciousness and suggest potential roles of transient states in brain disease assessment.

Microstructural profiles of thalamus and thalamocortical connectivity in patients with disorder of consciousness.

Thalamus and thalamocortical connectivity are crucial for consciousness; however, their microstructural changes in patients with a disorder of consciousness (DOC) have not yet been thoroughly characterized. In the present study, we applied the novel fixel-based analysis to comprehensively investigate the thalamus-related microstructural abnormalities in 10 patients with DOC using 7-T diffusion-weighted imaging data. We found that compared to healthy controls, patients with DOC showed reduced fiber density (FD) and fiber density and cross-section (FDC) in the mediodorsal, anterior, and ventral anterior thalamic nuclei, while fiber-bundle cross-section (FC) was not significantly altered in the thalamus. Impaired thalamocortical connectivity in the DOC cohort was mainly connected to the middle frontal gyrus, anterior cingulate gyrus, fusiform gyrus, and sensorimotor cortices, including the precentral gyrus and postcentral gyrus, with predominant microstructural abnormalities in FD and FDC. Correlation analysis showed that FC of the right mediodorsal thalamus was negatively correlated with the level of consciousness. Our results suggest that microstructural abnormalities of thalamus and thalamocortical connectivity in DOC were mainly attributed to axonal injury. In particular, the microstructural integrity of the thalamus is a vital factor in consciousness generation.

COVID-19 and hospital restrictions: physical disconnection and digital re-connection in disorders of consciousness.

Purpose: The coronavirus disease 2019 (COVID-19) pandemic forced hospitals to adopt tighter restrictions, the most impacting is no access to visitors. Disorder of consciousness (DOC) due to severe acquired brain injury is a condition needing neurorehabilitation and the role of relatives is essential, hence besides physical "disconnection" digital "re-connection" is crucial. We aimed to assess whether digital communication benefits in patients with DOC, considering the sensorial and emotional deprivation due to the COVID-19 emergency lock-down.Methods: For eleven consecutive patients with DOC admitted to our Intensive Neurorehabilitation Care (mean age: 45; females: 9), two observers registered neurobehavioral changes during a video-calls with their relatives. Heart-rate variability was measured before and during the calls. The video-call was performed by using two displays of different sizes: tablet (T-video-call) and large screen (LS-Video-call).Results: The video-calls impacted on the patients' vigilance and in the relationship with relatives. Moreover, positively impacted on their relatives. The current results showed significant greater impact on patients during the LS-video-call than when they are exposed to T-video-call.Conclusions: During the COVID-19 pandemic, besides the physical disconnection to stop the contagion spread, a "digital re-connection" is needed for all and especially for fragile population groups as patients with DOC.

Letter to the editor: COVID in patients with brain injury with a disorder of consciousness: a pathogenetic theory.

We recently published in this journal (Caronni and colleagues, Brain Injury, 2021-04-16) the first description of the spread of the SARS-CoV-2 infection in a cohort of brain injured patients with a disorder of consciousness (DOC). Surprisingly enough we showed that, in these patients, the COVID was moderate and did not result in fatalities. The pathogenesis of the COVID is characterized by the profound dysregulation of the immune system. To explain our findings, we speculated that the immunosuppression due to the brain injury could be protective against the development of the COVID in patients with DOC. More recently, a second group of authors (Marino and colleagues, PLoSOne, 2021-06-30) described the course of the COVID in an independent cohort of patients with DOC. Since our results were quite unexpected, we have been very comforted by the data reported by Marino and colleagues. Moreover, these data also offer a unique opportunity to further evaluate our theory regarding the COVID pathogenesis in patients with DOC. In the current Letter to the Editor it is shown that the independent data presented by Marino and colleagues do support our theory. Waiting for larger cohorts to further test it (and in case falsify it), our interpretation seems to remain valid.

Clinical course of SARS-CoV-2 infection in patients with severe acquired brain injury and a disorder of consciousness: an observational study.

Purpose: SARS-CoV-2 infection can cause the coronavirus disease (COVID), ranging from flu-like symptoms to interstitial pneumonia. Mortality is high in COVID pneumonia and it is the highest among the frailest. COVID could be particularly serious in patients with severe acquired brain injury (SABI), such as those with a disorder of consciousness. We here describe a cohort of patients with a disorder of consciousness exposed to SARS-CoV-2 early after their SABI.Materials and methods: The full cohort of 11 patients with SABI hospitalized in March 2020 in the IRCCS Fondazione Don Gnocchi rehabilitation (Milan, Italy) was recruited. Participants received SARS-CoV-2 testing and different clinical and laboratory data were collected.Results: Six patients contracted SARS-CoV-2 and four of them developed the COVID. Of these, one patient had ground-glass opacities on the chest CT scan, while the remaining three developed consolidations. No patient died and the overall respiratory involvement was mild, requiring in the worst cases low-flow oxygen.Conclusions: Here we report the clinical course of a cohort of patients with SABI exposed to SARS-CoV-2. The infection spread among patients and caused COVID in some of them. Unexpectedly, COVID was moderate, caused at most mild respiratory distress and did not result in fatalities.

Assessing emergence from a prolonged disorder of consciousness: Current opinion and practice in the UK.

BACKGROUND: A patient in PDOC must demonstrate functional object use or functional communication to confirm they have emerged from this state. A range of tasks and stimuli are used and patients must achieve 100% accuracy. As consciousness occurs along a continuum, determining emergence is not straightforward. OBJECTIVE: To establish the opinions of expert clinicians on how emergence is determined in practice. METHODS: An online survey was completed by clinicians working in specialist rehabilitation settings across the UK. Questions were asked about diagnosis and confidence, informal assessment, formal assessment, and family involvement. Descriptive statistics were used to analyse responses to closed questions. Responses to open questions were analysed using thematic analysis. RESULTS: Seventy-five surveys were analysed. Approximately a third (30.4 %) used tasks other than those recommended to determine emergence. A lack of confidence in tasks to detect the return of functional communication was reported by 46.4%. The majority (78.6%) reported they worked with patients who they felt had emerged, but could not demonstrate it based on the current criteria. A range of stimuli were employed, but 30.6% of respondents were not confident they could choose stimuli appropriately. Respondents reported a range of benefits and challenges when involving family in assessment.

How do we build a picture of a patient in prolonged disorder of consciousness?

Accurate diagnosis of prolonged disorders of consciousness can be challenging and requires the input of a specialist interdisciplinary team who are experienced in informal assessment as well as the administration of formal validated observational assessment tools. There is limited guidance on the selection of these assessment tools. This study examines the factors involved in a team's choice making and how choice of assessment helps build a picture of a patient. Twelve clinicians working within a specialist prolonged disorders of consciousness unit participated in the study. Five took part in an individual structured interview and seven took part in a focus group. Data were evaluated using thematic analysis. The results show that there was a range of factors which influenced decisions over choice of assessment tools. No one assessment tool is perfect and therefore participants favour combining the characteristics of two assessment tools in order to achieve a higher-quality assessment. The use of two assessment tools rather than one, is thought to be key in helping to build an overall picture of the patient. The findings of this study may be useful in the training of clinicians working with this specialist caseload, in the future development of tools themselves and in guiding further research into using a combination of assessment tools for best outcome in this patient group.

Nociception Coma Scale with personalized painful stimulation versus standard stimulus in non-communicative patients with disorders of consciousness.

INTRODUCTION: Persons with disorders of consciousness (DoC) may perceive pain without being able to communicate their discomfort. Nociception Coma Scale (NCS) and its revised form (NCS-R) have been proposed to assess nociception in coma survivors with DoC. OBJECTIVE: Aim of the present study was to compare, in non-communicative patients with DoC, NCS-R scores obtained with the standard pressure on fingernail bed (standard stimulus, SS) versus other personalized painful stimuli (PS), to verify possible correlations between NCS-R and Coma Recovery Scale-Revised (CRS-R). MATERIALS AND METHODS: Twenty-one patients with DoC were included in the study. Responsiveness and pain perception were assessed by CRS-R and NCS-R with standard stimulus (NCS-R-SS) and personalized stimulation (NCS-R-PS). Statistical analysis was performed with the nonparametric Wilcoxon test for comparison of both total NCS-R-SS and NCS-R-PS scores. RESULTS: NCS-R at admission showed that 9 of 21 patients (42.8%) had higher scores in response to personalized stimulus compared to standard stimulus. Significant correlation with CRS-R were found for both NCS-R-SS (R = 0.701, p = .008) and NCS-R-PS (R = 0.564, p = .045). Discussion: The preliminary results obtained in the present study suggest that NCS-R-PS may disclose pain perception in a larger number of non-communicative patients with DoC, compared to NCS-R-SS.

Functional Coma: Two Case Reports and a Review of the Literature.

BACKGROUND: Psychiatric illness can mimic a comatose state. The most common is a conversion reaction resulting in a functional coma, which poses a unique diagnostic challenge to the clinician. Little is known about this condition, and the literature is limited by inconsistent terminology and by a lack of high-quality evidence. OBJECTIVE: To provide a conceptual definition of functional coma, describe case examples, summarize management, and increase recognition of this often underacknowledged entity. METHODS: We present two cases and provide a comprehensive review of the literature on the differential diagnosis, pathophysiology, workup, and management. RESULTS: Functional coma is defined as an involuntary coma-like state that occurs in the absence of structural or metabolic damage to the brain and that is distinct from catatonia. This term should supplant the previous phrase of "psychogenic coma." Psychiatric disorders are frequently present premorbidly, but are not required for the diagnosis. About half of the cases occur in the perioperative setting. Physical exam can provide helpful clues, including passive resistance to eye opening or avoidance of the face with arm drop. Additional work-up, including laboratory studies, brain imaging, and electroencephalography, should be obtained but are unremarkable in functional coma. Case studies suggest that the episodes last for several hours, with a range of 45 minutes to 4 days. Treatment includes supportive management and careful psychoeducation. CONCLUSIONS: Functional coma should be conceptualized as a distinct condition from catatonia and psychogenic non-epileptic seizures. Additional clinical and translation research is needed to further explore the etiology of this condition.

Partially dead, partially separated: establishing the mechanism between ambiguous loss and grief reaction among caregivers of patients with prolonged disorders of consciousness.

OBJECTIVES:: To trace the psychological mechanism underlying caregivers' emotional experience in prolonged disorders of consciousness, by examining the mediating role of boundary ambiguity in the relationship between ambiguous loss and grief. DESIGN:: Cross-sectional design. SETTING:: The Respiratory Rehabilitation Division of a long-term medical and rehabilitation institute. SUBJECTS:: A total of 64 primary caregivers (69% female) of patients in a vegetative state ( n = 49) or minimally conscious state ( n = 15), with a mean age of 55.5 (SD = 12.3) years. Participants were mostly the patient's children (62%) or partners (27%). The mean caregiving duration was 4.9 (SD = 5.1) years. MAIN MEASURES:: The Boundary Ambiguity Scale, the Revised Need for Closure Scale, an adapted version of the multifactor Two-Track Bereavement Questionnaire, and a sociodemographic questionnaire, which included items regarding caregiving: frequency of visits and perception of the patient's psychological presence. RESULTS:: (1) Caregivers' grief scores (total TTBQ: mean = 2.97; SD = 0.55) did not significantly differ from those exhibited by a normative bereavement sample. (2) Time since injury did not affect caregivers' grief scores (three-year cut-point; P > .05). (3) Mediation analyses revealed that boundary ambiguity (mean = 34.03; SD = 7.55) significantly mediates the relationship between need for closure ( B = .11; confidence interval (CI) = .04-.23) and grief; frequency of visits ( B = .05, CI = .02-.10) and grief and perception of psychological presence ( B = .26, CI = .00-.61) and grief in three separate models. CONCLUSION:: Ambiguity concerning relational boundaries hinders caregivers' ongoing grief reaction and impedes their ability to integrate the loss. High frequency of visits, belief in the patient's psychological presence and difficulties in tolerating uncertainty are all clinical manifestations of caregivers' entangled experience.

Late recovery of responsiveness after intra-thecal baclofen pump implantation and the role of diffuse pain and severe spasticity: a case report.

Patients with a prolonged disorder of consciousness (DoC) may present with severe spasticity and diffuse pain, which might impair motor output, thus preventing any possible behavioral responsiveness. A 26-year-old man affected by frontoparietal hemorrhage was operated by hematoma evacuation and decompressive craniectomy; coma persisted for 1 month; cranioplasty and ventriculo-peritoneal shunting was performed after 4 months. At admission in rehabilitation, he was diagnosed as vegetative state/unresponsive wakefulness syndrome (VS/UWS). The implantation of intrathecal baclofen (ITB) pump (Medtronic SynchroMed™ II), 14 months after, (60 µg/daily), dramatically improved behavioral responsiveness according to Coma Recovery Scale-Revised (CRS-R) from 6 to 12 (1 month after ITB). Nociception Coma Scale-Revised (NCS-R) also changed from 4 to 8 at the same time points. This case report may be an example of covert cognition that should have been diagnosed as a functional locked-in syndrome or motor-cognitive dissociation, rather than as VS/UWS.

An International survey on diagnostic and prognostic protocols in patients with disorder of consciousness.

To date, no international guidelines or recommendations for diagnosis or prognosis of patients with disorders of consciousness (DoC) have been established. The International Brain Injury Association's (IBIA) Special Interest Group on Disorders of Consciousness (DoC-SIG) launched an international multicenter survey to compare diagnostic and prognostic procedures across countries and clinical settings. Objectives: To explore which specific diagnostic protocols and prognostic indices were utilized in the care for persons with DoC in different countries and to determine the usage, if any, of national guidelines in the care of such patients. Methods: The questionnaire included 17 questions in two distinct sections (I - clinical and instrumental tools and involvement of caregivers and II - clinical, anamnestic and instrumental markers). Results: Physicians composed 50% of the survey respondents (120) and were all involved in post-acute rehabilitation care. In the majority of countries, respondents reported that there were no national guidelines or recommendations for DoC care. The Glasgow Coma Scale (GCS) and the Coma Recovery Scale-Revised (CRS-R) were the most frequently used clinical scales for diagnostic purposes. The majority of respondents reported the involvement of caregivers in the evaluation of behavioral responsiveness of patient with DoC. The survey indicated that only a few centers performed neurophysiological investigations routinely as diagnostic instrumental procedures. Our results suggest that international guidelines and recommendations for the care of persons with DoC still need to be formulated and ideally agreed to by consensus.

Experience in Rehabilitation Medicine Affects Prognosis and End-of-Life Decision-Making of Neurologists: A Case-Based Survey.

BACKGROUND: Outcome predictions in patients with acute severe neurologic disorders are difficult and influenced by multiple factors. Since the decision for and the extent of life-sustaining therapies are based on the estimated prognosis, it is vital to understand which factors influence such estimates. This study examined whether previous professional experience with rehabilitation medicine influences physician decision-making. METHODS: A case vignette presenting a typical patient with an extensive brain stem infarction was developed and distributed online to clinical neurologists. Questions focused on prognosis, interpretation of an advanced directive, whether to withdraw life-sustaining treatments and information on prior rehabilitation experience from the survey respondent. RESULTS: Of the participating neurologists, 77% opted for the withdrawal of life-sustaining therapies (n = 70; response rate: 14.8%). This decision was not affected by age, gender, or length of clinical experience. Neurologists with experience in rehabilitation medicine tended to estimate a more positive prognosis than neurologists without, but this result was not significant (p = .13). There was an association between the intervention chosen and previous experience in rehabilitation; neurologists with experience in rehabilitation medicine opted significantly more often (31.8%) for continuing life-sustaining treatments than neurologists without such experience (8.7%, p = .04). CONCLUSION: Our results indicate that there are subjective factors influencing decisions to limit life-sustaining treatments that are based on previous professional experience. This finding emphasizes the variability and cognitive bias of such decision processes and should be integrated into future guidelines for specialist training on end-of-life decision-making.