Behavioral Recovery in Disorders of Consciousness: A Prospective Study With the Spanish Version of the Coma Recovery Scale–Revised

Neurobehavioral Progress and Signs of Transition in Children With Prolonged Disorders of Consciousness: A Retrospective Longitudinal Study With the Coma Recovery Scale-Revised

BACKGROUND

Research on disorders of consciousness in children is scarce and includes disparate and barely comparable participants and assessment instruments and therefore provides inconclusive information on the clinical progress and recovery in this population. This study retrospectively investigated the neurobehavioral progress and the signs of transition between states of consciousness in a group of children admitted to a rehabilitation program either with an unresponsive wakefulness syndrome (UWS) or in a minimally conscious state (MCS).

METHODS

Systematic weekly assessments were conducted with the Coma Recovery Scale-Revised (CRS-R) until emergence from MCS, discharge, or death.

RESULTS

Twenty-one children, nine admitted with a UWS and 12 admitted in an MCS, were included in the study. Four children with a UWS transitioned to an MCS with a CRS-R of 10 (9.2 to 12.2) by showing visual pursuit, visual fixation, or localization to noxious stimulation. Twelve children emerged from the MCS with a CRS-R of 20.5 (19 to 21.7). Children who emerged from the MCS had had a shorter time postinjury and higher CRS-R at admission, compared with those who did not emerge.

CONCLUSIONS

Almost half of the children who were admitted with a UWS transitioned to an MCS, and almost all who were admitted in an MCS emerged from this state. Children who emerged had shorter times since injury and higher scores on the CRS-R at admission, compared with those who did not emerge.

Which information derived from the Coma Recovery Scale-Revised provides the most reliable prediction of clinical diagnosis and recovery of consciousness? A comparative study using machine learning techniques

BACKGROUND

The Coma Recovery Scale-Revised (CRS-R) is the most recommended clinical tool to examine the neurobehavioral condition of individuals with disorders of consciousness (DOCs). Different studies have investigated the prognostic value of the information provided by the conventional administration of the scale, while other measures derived from the scale have been proposed to improve the prognosis of DOCs. However, the heterogeneity of the data used in the different studies prevents a reliable comparison of the identified predictors and measures.

AIM

This study investigates which information derived from the CRS-R provides the most reliable prediction of both the clinical diagnosis and recovery of consciousness at the discharge of a long-term neurorehabilitation program.

DESIGN

Retrospective observational multisite study.

SETTING

The enrollment was performed in three neurorehabilitation facilities of the same hospital network.

POPULATION

A total of 171 individuals with DOCs admitted to an inpatient neurorehabilitation program for a minimum of 3 months were enrolled.

METHODS

Machine learning classifiers were trained to predict the clinical diagnosis and recovery of consciousness at discharge using clinical confounders and different metrics extracted from the CRS-R scale.

RESULTS

Results showed that the neurobehavioral state at discharge was predicted with acceptable and comparable predictive value with all the indices and measures derived from the CRS-R, but for the clinical diagnosis and the Consciousness Domain Index, and the recovery of consciousness was predicted with higher accuracy and similarly by all the investigated measures, with the exception of initial clinical diagnosis.

CONCLUSIONS

Interestingly, the total score in the CRS-R and, especially, the total score in its subscales provided the best overall results, in contrast to the clinical diagnosis, which could indicate that a comprehensive measure of the clinical diagnosis rather than the condition of the individuals could provide a more reliable prediction of the neurobehavioral progress of individuals with prolonged DOC.

CLINICAL REHABILITATION IMPACT

The results of this work have important implications in clinical practice, offering a more accurate prognosis of patients and thus giving the possibility to personalize and optimize the rehabilitation plan of patients with DoC using low-cost and easily collectable information.

Minimally conscious state plus versus minus: Likelihood of emergence and long-term functional independence

OBJECTIVE

Severe brain injuries can result in disorders of consciousness, such as the Minimally Conscious State (MCS), where individuals display intermittent yet discernible signs of conscious awareness. The varied levels of responsiveness and awareness observed in this state have spurred the progressive delineation of two subgroups within MCS, termed "plus" (MCS+) and "minus" (MCS-). However, the clinical validity of these classifications remains uncertain. This study aimed to investigate and compare the likelihood of emergence from MCS, as well as the functional independence after emergence, in individuals categorized as in MCS+ and MCS-.

METHODS

Demographic and behavioral data of 80 participants, admitted as either in MCS+ (n = 30) or MCS- (n = 50) to a long-term neurorehabilitation unit, were retrospectively analyzed. The neurobehavioral condition of each participant was evaluated weekly until discharge, demise, or emergence from MCS. The functional independence of those participants who emerged from MCS was assessed 6 months after emergence.

RESULTS

While only about half of the individuals classified as in MCS- (n = 24) emerged from the MCS, all those admitted as in MCS+ did, and in a shorter postinjury period. Despite these differences, all individuals who emerged from the MCS demonstrated similar high disability and low functional independence 6 months after emergence, regardless of their state at admission.

INTERPRETATION

Individuals classified as MCS+ exhibited a higher likelihood of emergence and a shorter time to emergence compared to those in MCS-. However, the level of functional independence 6 months after emergence was found to be unrelated to the initial state at admission.

Central autonomic network and early prognosis in patients with disorders of consciousness

The central autonomic network (CAN) plays a crucial role in modulating the autonomic nervous system. Heart rate variability (HRV) is a valuable marker for assessing CAN function in disorders of consciousness (DOC) patients. We used HRV analysis for early prognosis in 58 DOC patients enrolled within ten days of hospitalization. They underwent a five-minute electrocardiogram during baseline and acoustic/visual stimulation. The coma recovery scale-revised (CRS-R) was used to define the patient's consciousness level and categorize the good/bad outcome at three months. The high-frequency Power Spectrum Density and the standard deviation of normal-to-normal peaks in baseline, the sample entropy during the stimulation, and the time from injury features were used in the support vector machine analysis (SVM) for outcome prediction. The SVM predicted the patients' outcome with an accuracy of 96% in the training test and 100% in the validation test, underscoring its potential to provide crucial clinical information about prognosis.

Predicting Functional Dependency in Patients with Disorders of Consciousness: A TBI-Model Systems and TRACK-TBI Study

OBJECTIVE

It is not currently possible to predict long-term functional dependency in patients with disorders of consciousness (DoC) after traumatic brain injury (TBI). Our objective was to fit and externally validate a prediction model for 1-year dependency in patients with DoC ≥ 2 weeks after TBI.

METHODS

We included adults with TBI enrolled in TBI Model Systems (TBI-MS) or Transforming Research and Clinical Knowledge in TBI (TRACK-TBI) studies who were not following commands at rehabilitation admission or 2 weeks post-injury, respectively. We fit a logistic regression model in TBI-MS and validated it in TRACK-TBI. The primary outcome was death or dependency at 1 year post-injury, defined using the Disability Rating Scale.

RESULTS

In the TBI-MS Discovery Sample, 1,960 participants (mean age 40 [18] years, 76% male, 68% white) met inclusion criteria, and 406 (27%) were dependent 1 year post-injury. In a TBI-MS held out cohort, the dependency prediction model's area under the receiver operating characteristic curve was 0.79 (95% CI 0.74-0.85), positive predictive value was 53% and negative predictive value was 86%. In the TRACK-TBI external validation (n = 124, age 40 [16] years, 77% male, 81% white), the area under the receiver operating characteristic curve was 0.66 (0.53, 0.79), equivalent to the standard IMPACTcore + CT score (p = 0.8).

INTERPRETATION

We developed a 1-year dependency prediction model using the largest existing cohort of patients with DoC after TBI. The sensitivity and negative predictive values were greater than specificity and positive predictive values. Accuracy was diminished in an external sample, but equivalent to the IMPACT model. Further research is needed to improve dependency prediction in patients with DoC after TBI. ANN NEUROL 2023;94:1008-1023.

Prognostication in Prolonged and Chronic Disorders of Consciousness

Patients with prolonged disorders of consciousness (DOCs) longer than 28 days may continue to make significant gains and achieve functional recovery. Occasionally, this recovery trajectory may extend past 3 (for nontraumatic etiologies) and 12 months (for traumatic etiologies) into the chronic period. Prognosis is influenced by several factors including state of DOC, etiology, and demographics. There are several testing modalities that may aid prognostication under active investigation including electroencephalography, functional and anatomic magnetic resonance imaging, and event-related potentials. At this time, only one treatment (amantadine) has been routinely recommended to improve functional recovery in prolonged DOC. Given that some patients with prolonged or chronic DOC have the potential to recover both consciousness and functional status, it is important for neurologists experienced in prognostication to remain involved in their care.

Coma Recovery Scale-Revised Predicts Disability Rating Scale in Acute Rehabilitation of Severe Traumatic Brain Injury

OBJECTIVE

To explore the prognostic value of the Coma Recovery Scale-Revised (CRS-R) in predicting disability outcomes in patients with severe traumatic brain injury using the Disability Rating Scale (DRS).

DESIGN

Secondary analysis including linear and logistic regressions were performed.

SETTING

Data were collected in a previous clinical trial.

PARTICIPANTS

One hundred eighty-four participants across 3 countries (N=184).

MAIN OUTCOME MEASURES

Disability Rating Scales.

RESULTS

Analyses showed an inverse relation between CRS-R scores obtained at baseline and change in DRS scores at 6 weeks. Similarly, changes in CRS-R scores between baseline and 4 weeks were also found to have an inverse relation to change in DRS scores at 6 weeks.

CONCLUSIONS

This study generates a tool that can be used to predict the probability that a patient with severe traumatic brain injury lands in 1 of 3 disability categories. The CRS-R may be useful in prognostication of disability in patients with severe traumatic brain injury.

Predicting Functional Dependency in Patients with Disorders of Consciousness: A TBI-Model Systems and TRACK-TBI Study

Importance

There are currently no models that predict long-term functional dependency in patients with disorders of consciousness (DoC) after traumatic brain injury (TBI).

Objective

Fit, test, and externally validate a prediction model for 1-year dependency in patients with DoC 2 or more weeks after TBI.

Design

Secondary analysis of patients enrolled in TBI Model Systems (TBI-MS, 1988-2020, Discovery Sample) or Transforming Research and Clinical Knowledge in TBI (TRACK-TBI, 2013-2018, Validation Sample) and followed 1-year post-injury.

Setting

Multi-center study at USA rehabilitation hospitals (TBI-MS) and acute care hospitals (TRACK-TBI).

Participants

Adults with TBI who were not following commands at rehabilitation admission (TBI-MS; days post-injury vary) or 2-weeks post-injury (TRACK-TBI).

Exposures

In the TBI-MS database (model fitting and testing), we screened demographic, radiological, clinical variables, and Disability Rating Scale (DRS) item scores for association with the primary outcome.

Main Outcome

The primary outcome was death or complete functional dependency at 1-year post-injury, defined using a DRS-based binary measure (DRS Depend ), indicating need for assistance with all activities and concomitant cognitive impairment.

Results

In the TBI-MS Discovery Sample, 1,960 subjects (mean age 40 [18] years, 76% male, 68% white) met inclusion criteria and 406 (27%) were dependent at 1-year post-injury. A dependency prediction model had an area under the receiver operating characteristic curve (AUROC) of 0.79 [0.74, 0.85], positive predictive value of 53%, and negative predictive value of 86% for dependency in a held-out TBI-MS Testing cohort. Within the TRACK-TBI external validation sample (N=124, age 40 [16], 77% male, 81% white), a model modified to remove variables not collected in TRACK-TBI, had an AUROC of 0.66 [0.53, 0.79], equivalent to the gold-standard IMPACT core+CT score (0.68; 95% AUROC difference CI: -0.2 to 0.2, p=0.8).

Conclusions and Relevance

We used the largest existing cohort of patients with DoC after TBI to develop, test and externally validate a prediction model of 1-year dependency. The model’s sensitivity and negative predictive value were greater than specificity and positive predictive value. Accuracy was diminished in an external sample, but equivalent to the best-available models. Further research is needed to improve dependency prediction in patients with DoC after TBI.

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.

Exploring the measurement of pediatric cognitive-communication disorders in traumatic brain injury research: A scoping review

OBJECTIVE

To synthesize information about the constructs measured, measurement instruments used, and the timing of assessment of cognitive-communication disorders (CCDs) in pediatric traumatic brain injury (TBI) research.

METHODS AND PROCEDURES

Scoping review conducted in alignment with Arksey and O'Malley's five-stage methodological framework and reported per the PRISMA extension for Scoping Reviews. Inclusion criteria: (a) cohort description, case-control, and treatment studies; (b) participants with TBI aged 5-18 years; (c) communication or psychosocial outcomes; and (d) English full-text journal articles. The first author reviewed all titles, abstracts, and full-text articles; 10% were independently reviewed.

OUTCOMES AND RESULTS

Following screening, a total of 687 articles were included and 919 measurement instruments, measuring 2134 unique constructs, were extracted. The Child Behavior Checklist was the most used measurement instrument and 'Global Outcomes/Recovery' was the construct most frequently measured. The length of longitudinal monitoring ranged between ≤3 months and 16 years.

CONCLUSIONS AND IMPLICATIONS

We found considerable heterogeneity in the constructs measured, the measurement instruments used, and the timing of CCD assessment in pediatric TBI research. A consistent approach to measurement may support clinical decision-making and the efficient use of data beyond individual studies in systematic reviews and meta-analyses.

Validity of the Early Functional Ability scale (EFA) among critically ill patients undergoing early neurological rehabilitation

Background

A reliable assessment of the functional abilities of patients after severe brain damage is crucial for valid prognostication and treatment decisions, but most clinical scales are of limited use among this specific group of patients.

Aim

The present study investigates the usefulness of the Early Functional Ability (EFA) scale, which determines the functional abilities of severely impaired patients.

Methods

Critically ill patients consecutively admitted to early neurological rehabilitation were screened for eligibility. We assessed the correlation between the EFA scale and (i) the Early Rehabilitation Barthel Index (ERBI), and (ii) the Coma Recovery Scale-Revised (CRS-R). The 1-year outcome on the Glasgow Outcome Scale-extended (GOSE) was used to examine the predictive validity. Demographical and medical variables were entered into univariate and multivariate binary regression models to identify independent predictors of 1-year outcome.

Results

Two hundred fifty-seven patients (168 men) with a median age of 62 years (IQR = 51–75) were enrolled. The correlation of the EFA scale with the CRS-R was high but low with the ERBI upon admission. Multivariate regression analysis yielded the vegetative subscale of the EFA scale as the only independent predictor for the 1-year outcome of patients admitted to early neurological rehabilitation.

Conclusions

This study shows a high correlation of the EFA scale with the CRS-R but a weak correlation with the ERBI in patients with low functional abilities. With improving patient abilities, these correlations were partly reversed. Thus, the EFA scale is a useful tool to assess the functional abilities and the prognosis of critically ill patients adequately and may be more feasible than other scales.

One-year outcome of brain injured patients undergoing early neurological rehabilitation: a prospective observational study

Background

The present study intended to analyze the outcome of patients with severe brain injury one-year after discharge from early rehabilitation.

Methods

Early neurological rehabilitation patients admitted to intensive or intermediate care units and discharged between June 2018 and May 2020 were screened for eligibility. The level of consciousness was evaluated using the Coma Recovery Scale-Revised (CRS-R) upon admission and at discharge. At one-year follow-up, the outcome was assessed with the Glasgow Outcome Scale-extended (GOSE). Demographical and clinical data collected during inpatient rehabilitation were used to predict the outcome 1 year after discharge.

Results

Two hundred sixty-four patients (174 males, 90 females) with a median age of 62 years (IQR = 51–75) and a median duration of their disease of 18 days (IQR = 12–28) were included in the study. At follow-up, the mortality rate was 27% (n = 71). Age and discharge CRS-R total score were independent predictors in a Cox proportional hazards model with death (yes/no) as the dependent variable. According to the GOSE interviews, most patients were either dead (n = 71; 27%), in a vegetative state (n = 28; 11%) or had a severe disability (n = 124; 47%), whereas only a few patients showed a moderate disability (n = 18; 7%) or a good recovery (n = 23; 9%) 1 year after discharge. Age, non-traumatic etiology, discharge CRS-R total score and length of stay independently predicted whether the outcome was good or poor at follow-up.

Conclusion

Age was an important predictor for outcome at one-year follow-up, which might be due to altered brain plasticity and more comorbidities in elderly subjects. In addition, the present study demonstrated that the CRS-R total score at discharge might be more important for the prediction of one-year outcome than the initial assessment upon admission.

Towards consensus on visual pursuit and visual fixation in patients with disorders of consciousness. A Delphi study

BACKGROUND

The aim of this Delphi study was to reach consensus about definition, operationalization and assessment of visual pursuit (VP) and visual fixation (VF).

METHODS

In a three-round international Delphi study, clinical and research experts on disorders of consciousness indicated their level of agreement on 87 statements using a 5-point Likert scale. Consensus for agreement was defined by a median of 5, an interquartile range (IQR) ≤ 1, and ≥ 80% indicating moderate or strong agreement.

RESULTS

Forty-three experts from three continents participated, 32 completed all three rounds. For VP, the consensus statements with the highest levels of agreement were on the term 'pursuit of a visual stimulus', the description 'ability to follow visually in horizontal and/or vertical plane', a duration > 2 s, tracking in horizontal and vertical planes, and a frequency of more than 2 times per assessment. For VF, consensus statements with the highest levels of agreement were on the term 'sustained VF', the description 'sustained fixation in response to a salient stimulus', a duration of > 2 s and a frequency of 2 or more times per assessment. The assessment factors with the highest levels of agreement were personalized stimuli, the use of eye tracking technology, a patient dependent time of assessment, sufficient environmental light, upright posture, and the necessity to exclude ocular/oculomotor problems.

CONCLUSION

This first international Delphi study on VP and VF in patients with disorders of consciousness provides provisional operational definitions and an overview of the most relevant assessment factors.

Visual fixation in disorders of consciousness: Development of predictive models to support differential diagnosis

The visual fixation represents a doubtful behavioral sign to discriminate Vegetative from Minimally Conscious State (MCS). To disentangle its meaning, we fitted univariate and multivariable logistic regression models matching different neurophysiological and neuroimaging data of 54 patients with Disorders of Consciousness to select the best model predicting which visual performance (visual blink or pursuit) was shown by patients and the best predictors set. The best models found highlighted the importance of the structural MRI and the visual evoked potentials data in predicting visual pursuit. Then, a qualitative pilot test was made on four patients showing visual fixation revealing that the obtained models correctly predict whether the patients' visual performance could support/correlate to a cognitively mediated behavior. The present pilot models could help clinicians to evaluate if the visual fixation response can support the MCS diagnosis.

When, How, and to What Extent Are Individuals with Unresponsive Wakefulness Syndrome Able to Progress? Neurobehavioral Progress

Accurate estimation of the neurobehavioral progress of patients with unresponsive wakefulness syndrome (UWS) is essential to anticipate their most likely clinical course and guide clinical decision making. Although different studies have described this progress and possible predictors of neurobehavioral improvement in these patients, they have methodological limitations that could restrict the validity and generalization of the results. This study investigates the neurobehavioral progress of 100 patients with UWS consecutively admitted to a neurorehabilitation center using systematic weekly assessments based on standardized measures, and the prognostic factors of changes in their neurobehavioral condition. Our results showed that, during the analyzed period, 34% of the patients were able to progress from UWS to minimally conscious state (MCS), 12% of the total sample (near one third from those who progressed to MCS) were able to emerge from MCS, and 10% of the patients died. Transition to MCS was mostly denoted by visual signs, which appeared either alone or in combination with motor signs, and was predicted by etiology and the score on the Coma Recovery Scale-Revised at admission with an accuracy of 75%. Emergence from MCS was denoted in the same proportion by functional communication and object use. Predictive models of emergence from MCS and mortality were not valid and the identified predictors could not be accounted for.

Auditory Event-Related "Global Effect" Predicts Recovery of Overt Consciousness

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.

When, How, and to What Extent Are Individuals with Unresponsive Wakefulness Syndrome Able to Progress? Functional Independence

Accurate estimation of the functional independence of patients with unresponsive wakefulness syndrome (UWS) is essential to adjust family and clinical expectations and plan long-term necessary resources. Although different studies have described the clinical course of these patients, they have methodological limitations that could restrict generalization of the results. This study investigates the neurobehavioral progress of 100 patients with UWS consecutively admitted to a neurorehabilitation center using systematic weekly assessments based on standardized measures, and the functional independence staging of those patients who emerged from a minimally conscious state (MCS) during the first year post-emergence. Our results showed that one year after emergence, most patients were severely dependent, although some of them showed extreme or moderate severity. Clinically meaningful functional improvement was less likely to occur in cognitively-demanding activities, such as activities of daily living and executive function. Consequently, the use of specific and staging functional independence measures, with domain-specific evaluations, are recommended to detect the functional changes that might be expected in these patients. The information provided by these instruments, together with that obtained from repeated assessments of the preserved consciousness with standardized instruments, could help clinicians to adjust expectations and plan necessary resources for this population.

Habituation of auditory startle reflex is a new sign of minimally conscious state

Neurological examination of non-communicating patients relies on a few decisive items that enable the crucial distinction between vegetative state (VS)-also coined unresponsive wakefulness syndrome (UWS)-and minimally conscious state. Over the past 10 years, this distinction has proven its diagnostic value as well as its important prognostic value on consciousness recovery. However, clinicians are currently limited by three factors: (i) the current behavioural repertoire of minimally conscious state items is limited and restricted to a few cognitive domains in the goldstandard revised version of the Coma Recovery Scale; (ii) a proportion of ∼15-20% clinically VS/UWS patients are actually in a richer state than VS/UWS as evidenced by functional brain imaging; and (iii) the neurophysiological and cognitive interpretation of each minimally conscious state item is still unclear and debated. In the current study we demonstrate that habituation of the auditory startle reflex (hASR) tested at bedside constitutes a novel, simple and powerful behavioural sign that can accurately distinguish minimally conscious state from VS/UWS. In addition to enlarging the minimally conscious state items repertoire, and therefore decreasing the low sensitivity of current behavioural measures, we also provide an original and rigorous description of the neurophysiological basis of hASR through a combination of functional (high density EEG and 18F-fluorodeoxyglucose PET imaging) and structural (diffusion tensor imaging MRI) measures. We show that preservation of hASR is associated with the functional and structural integrity of a brain-scale fronto-parietal network, including prefrontal regions related to control of action and inhibition, and meso-parietal areas associated with minimally conscious and conscious states. Lastly, we show that hASR predicts 6-month improvement of consciousness. Taken together, our results show that hASR is a cortically-mediated behaviour, and suggest that it could be a new clinical item to clearly and accurately identify non-communicating patients who are in the minimally conscious state.

Temporal Profile of Recovery of Communication in Patients With Disorders of Consciousness After Severe Brain Injury

OBJECTIVE

Characterize the temporal profile of recovery of communication after severe brain injury.

DESIGN

Retrospective cohort study.

SETTING

Inpatient rehabilitation hospital.

PARTICIPANTS

Patients with severe acquired brain injury and no evidence of communication on the Coma Recovery Scale-Revised (CRS-R) (N=175).

MAIN OUTCOME MEASURES

Time from injury to recovery of intentional communication (IC, inconsistent yes/no responses) and functional communication (FC, consistent and accurate yes/no responses) on the CRS-R Communication subscale.

RESULTS

Patients (N=175) were included in the primary observation period of the first 8 weeks of inpatient rehabilitation (median [interquartile range, IQR]: 48 [27-61] years old, 105 men, 28 [21-38] days postinjury, 100 traumatic etiology). Fifty-four patients (31%) did not recover IC or FC. Thirty patients (17%) recovered IC only (median [IQR] days from injury to IC= 40 [34-54]), 72 patients (41%) recovered IC followed by FC (days from injury to FC=50 [42-61]), and 19 patients (11%) recovered FC without first recovering IC (43 [32-63]). The patients who recovered neither IC nor FC within 8 weeks of admission were admitted to rehabilitation later than those who recovered IC and/or FC (P<.01). Sixteen patients who did not recover communication within 8 weeks of admission to rehabilitation subsequently recovered FC prior to discharge.

CONCLUSIONS

In patients with severe brain injury receiving inpatient rehabilitation, discernible yes-no responses emerged approximately 6 weeks postinjury and became reliable 1 week later. Approximately 1 in 3 patients did not demonstrate IC or FC within 8 weeks of admission to rehabilitation, although 33% of these individuals recovered communication prior to discharge. In total, 61% of patients recovered FC prior to discharge from rehabilitation.

Behavioral Recovery and Early Decision Making in Patients with Prolonged Disturbance in Consciousness after Traumatic Brain Injury

The extent of behavioral recovery that occurs in patients with traumatic disorders of consciousness (DoC) following discharge from the acute care setting has been under-studied and increases the risk of overly pessimistic outcome prediction. The aim of this observational cohort study was to systematically track behavioral and functional recovery in patients with prolonged traumatic DoC following discharge from the acute care setting. Standardized behavioral data were acquired from 95 patients in a minimally conscious (MCS) or vegetative state (VS) recruited from 11 clinic sites and randomly assigned to the placebo arm of a previously completed prospective clinical trial. Patients were followed for 6 weeks by blinded observers to determine frequency of recovery of six target behaviors associated with functional status. The Coma Recovery Scale-Revised and Disability Rating Scale were used to track reemergence of target behaviors and assess degree of functional disability, respectively. Twenty percent (95% confidence interval [CI]: 13-30%) of participants (mean age 37.2; median 47 days post-injury; 69 men) recovered all six target behaviors within the 6 week observation period. The odds of recovering a specific target behavior were 3.2 (95% CI: 1.2-8.1) to 7.8 (95% CI: 2.7-23.0) times higher for patients in MCS than for those in VS. Patients with preserved language function ("MCS+") recovered the most behaviors (p ≤ 0.002) and had the least disability (p ≤ 0.002) at follow-up. These findings suggest that recovery of high-level behaviors underpinning functional independence is common in patients with prolonged traumatic DoC. Clinicians involved in early prognostic counseling should recognize that failure to emerge from traumatic DoC before 28 days does not necessarily portend unfavorable outcome.

Which behaviours are first to emerge during recovery of consciousness after severe brain injury?

BACKGROUND

Early detection of consciousness after severe brain injury is critical for establishing an accurate prognosis and planning appropriate treatment.

OBJECTIVES

To determine which behavioural signs of consciousness emerge first and to estimate the time course to recovery of consciousness in patients with severe acquired brain injury.

METHODS

Retrospective observational study using the Coma Recovery Scale-Revised and days to recovery of consciousness in 79 patients (51 males; 34 with traumatic brain injury; median [IQR] age 48 [26-61] years; median time since injury 26 [20-36] days) who transitioned from coma or unresponsive wakefulness syndrome (UWS)/vegetative state (VS) to the minimally conscious state (MCS) or emerged from MCS during inpatient rehabilitation.

RESULTS

Visual pursuit was the most common initial sign of MCS (41% of patients; 95% CI [30-52]), followed by reproducible command-following (25% [16-35]) and automatic movements (24% [15-33]). Ten other behaviours emerged first in less than 16% of cases. Median [IQR] time to recovery of consciousness was 44 [33-59] days. Etiology did not significantly affect time to recovered consciousness.

CONCLUSION

Recovery of consciousness after severe brain injury is most often signalled by reemergence of visual pursuit, reproducible command-following and automatic movements. Clinicians should use assessment measures that are sensitive to these behaviours because early detection of consciousness is critical for accurate prognostication and treatment planning.

Genetic algorithms for feature selection when classifying severe chronic disorders of consciousness

The diagnosis and prognosis of patients with severe chronic disorders of consciousness are still challenging issues and a high rate of misdiagnosis is evident. Hence, new tools are needed for an accurate diagnosis, which will also have an impact on the prognosis. In recent years, functional Magnetic Resonance Imaging (fMRI) has been gaining more and more importance when diagnosing this patient group. Especially resting state scans, i.e., an examination when the patient does not perform any task in particular, seems to be promising for these patient groups. After preprocessing the resting state fMRI data with a standard pipeline, we extracted the correlation matrices of 132 regions of interest. The aim was to find the regions of interest which contributed most to the distinction between the different patient groups and healthy controls. We performed feature selection using a genetic algorithm and a support vector machine. Moreover, we show by using only those regions of interest for classification that are most often selected by our algorithm, we get a much better performance of the classifier.

Wisdom of the caregivers: pooling individual subjective reports to diagnose states of consciousness in brain-injured patients, a monocentric prospective study

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 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 PARTICIPANTS

Patients 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.

RESULTS

692 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).

CONCLUSIONS

DoC-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.

Cervical Spinal Cord Stimulation for the Vegetative State: A Preliminary Result of 12 Cases

OBJECTIVES

Data on the treatment of the vegetative state (VS) with cervical spinal cord stimulation (cSCS) are limited and prognostic factors are inconclusive. In this study, we present our experience of treating 12 VS patients with cSCS and discuss the prognostic factors.

METHODS

Twelve VS patients were enrolled. Preoperative assessments included CT/MRI, PET, brainstem auditory evoked potentials (BAEPs), somatosensory evoked potentials (SEPs), and electroencephalogram (EEG). cSCS surgeries were performed at West China Hospital. The electrode was implanted in the epidural space of the C2-4 vertebrae. Levels of consciousness were evaluated based on the Coma Recovery Scale-Revised (CRS-R) at baseline and during follow-up.

RESULTS

The average follow-up was 11.1 months. The average CRS-R score at the last evaluation was 10.8, which was significantly improved compared with the baseline score (6.25). Five patients achieved responsive outcomes (three recovered and two evolved to a minimally conscious state) and seven achieved unresponsive outcomes (six remained in VS and one died). Age, preoperative CRS-R score, the interval between acute comatose injury and cSCS, and the Vth wave of BAEPs did not differ significantly between the responsive group and the unresponsive group. Appearance of the N20 of SEPs and multifocal abnormalities on CT/MRI and PET were significantly associated with a better outcome, while the etiology of ischemia and anoxia (IAA) was significantly associated with a poor outcome.

CONCLUSIONS

cSCS should be a glimmer of hope for VS patients. Patients whose N20 is elicited or whose CT/MRI or PET demonstrates multifocal abnormalities are more likely to benefit from cSCS, whereas those with an IAA etiology have a lower likelihood of recovery after cSCS.

Reduced delta-band modulation underlies the loss of P300 responses in disorders of consciousness

OBJECTIVE

The P300 component of a sensory event-related potential is one of the major electrophysiological markers used to explore remnants of cognitive function in patients with disorders of consciousness (DoC). However, measuring the P300 in patients is complicated by significant inter-trial variability commonly observed in levels of arousal and awareness. To overcome this limitation, we analyzed single-trial modulation of power in the delta and theta frequency bands, which underlie the P300.

METHODS

In a preliminary cross-sectional study using a 24-channel EEG and a passive own-name oddball paradigm, we analyzed event-related synchronization (ERS) across trials in the delta and theta bands in a sample of 10 control and 12 DoC subjects.

RESULTS

In comparison to controls, DoC subjects presented a low percentage of trials where delta ERS was observed. In particular, coordinated modulation between delta and theta in response to the stimulus was absent, with a high percentage of trials where only theta ERS was observed. Further, we found a positive correlation between the percentage of epochs with delta ERS and the strength of the P300.

CONCLUSIONS

Reduced modulation of spectral activity in the delta band in response to stimuli indicates a dissociation in the activity of the neural networks that oscillate in delta and theta ranges and contribute to the generation of the P300.

SIGNIFICANCE

The reduction in spectral modulation observed in DoC provides a deeper understanding of neurophysiological dysfunction and the means to develop a more fine-grained marker of residual cognitive function in individual patients.

Minimally conscious state or cortically mediated state?

Durable impairments of consciousness are currently classified in three main neurological categories: comatose state, vegetative state (also recently coined unresponsive wakefulness syndrome) and minimally conscious state. While the introduction of minimally conscious state, in 2002, was a major progress to help clinicians recognize complex non-reflexive behaviours in the absence of functional communication, it raises several problems. The most important issue related to minimally conscious state lies in its criteria: while behavioural definition of minimally conscious state lacks any direct evidence of patient's conscious content or conscious state, it includes the adjective 'conscious'. I discuss this major problem in this review and propose a novel interpretation of minimally conscious state: its criteria do not inform us about the potential residual consciousness of patients, but they do inform us with certainty about the presence of a cortically mediated state. Based on this constructive criticism review, I suggest three proposals aiming at improving the way we describe the subjective and cognitive state of non-communicating patients. In particular, I present a tentative new classification of impairments of consciousness that combines behavioural evidence with functional brain imaging data, in order to probe directly and univocally residual conscious processes.

Improvement on the Coma Recovery Scale-Revised During the First Four Weeks of Hospital Stay Predicts Outcome at Discharge in Intensive Rehabilitation After Severe Brain Injury

OBJECTIVES

To evaluate the prognostic utility of serial assessment on the Coma Recovery Scale-Revised (CRS-R) during the first 4 weeks of intensive rehabilitation in patients surviving a severe brain injury.

DESIGN

Prospective cohort study.

SETTING

An intensive rehabilitation unit.

PARTICIPANTS

Patients (N=110) consecutively admitted to the intensive rehabilitation unit. Inclusion criteria were (1) a diagnosis of unresponsive wakefulness syndrome (UWS) or minimally conscious state (MCS) caused by an acquired brain injury, and (2) aged >18 years.

INTERVENTIONS

All patients underwent clinical evaluations using the Italian version of the CRS-R during the first month of hospital stay.

MAIN OUTCOME MEASURES

Behavioral classification on the CRS-R and the score on the Glasgow Outcome Scale (GOS) at final discharge. Patients transitioning from UWS to MCS or emergence from MCS (E-MCS), and from MCS to E-MCS were classified as patients with improved responsiveness (IR).

RESULTS

After a mean ± SD hospital stay of 5.3±2.7 months, 59 of 110 patients (53.6%) achieved IR. In the multivariable analysis, a higher CRS-R score change at week 4 (odds ratio =1.99; 95% confidence interval [CI], 1.49-2.66; P<.001) was the only significant predictor of IR at discharge. Fifty-three patients (48.2%) were classified as severely impaired at discharge (GOS=3). In the multivariable analysis, higher GOS scores were related to a higher CRS-R score at admission (B=.051; 95% CI, .027-.074; P<.001), a higher CRS-R score change at week 4 (B=.087; 95% CI, .064-.110; P<.001), and an absence of severe infections (B=-.477; 95% CI, -.778 to -.176; P=.002).

CONCLUSIONS

An improvement on the total CRS-R score and on different subscales across the first 4 weeks of inpatient rehabilitation discriminates patients who will have a better outcome at discharge, providing information for rehabilitation planning and for communication with patients and their caregivers.

Survival and consciousness recovery are better in the minimally conscious state than in the vegetative state

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 Pitié-Salpêtrière 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.

Current validity of diagnosis of permanent vegetative state: A longitudinal study in a sample of patients with altered states of consciousness

INTRODUCTION

Altered states of consciousness have traditionally been associated with poor prognosis. At present, clinical differences between these entities are beginning to be established.

METHOD

Our study included 37 patients diagnosed with vegetative state/unresponsive wakefulness syndrome (UWS) and 43 in a minimally conscious state (MCS) according to the Coma Recovery Scale-Revised (CRS-R). All patients were followed up each month for at least 6 months using the CRS-R. We recorded the time points when vegetative state progressed from 'persistent' to 'permanent' based on the cut-off points established by the Multi-Society-Task-Force: 12 months in patients with traumatic injury and 3 months in those with non-traumatic injury. A logistic regression model was used to determine the factors potentially predicting which patients will emerge from MCS.

RESULTS

In the UWS group, 23 patients emerged from UWS but only 9 emerged from MCS. Of the 43 patients in the MCS group, 26 patients emerged from that state during follow-up. Eight of the 23 patients (34.7%) who emerged from UWS and 17 of the 35 (48.6%) who emerged from MCS recovered after the time points proposed by the Multi-Society-Task-Force. According to the multivariate regression analysis, aetiology (P<.01), chronicity (P=.01), and CRS-R scores at admission (P<.001) correctly predicted emergence from MCS in 77.5% of the cases.

CONCLUSIONS

UWS and MCS are different clinical entities in terms of diagnosis and outcomes. Some of the factors traditionally associated with poor prognosis, such as time from injury and likelihood of recovery, should be revaluated.

The Role of Neuroimaging Techniques in Establishing Diagnosis, Prognosis and Therapy in Disorders of Consciousness

Non-communicative brain damaged patients raise important clinical and scientific issues. Here, we review three major pathological disorders of consciousness: coma, the unresponsive wakefulness syndrome and the minimally conscious state. A number of clinical studies highlight the difficulty in making a correct diagnosis in patients with disorders of consciousness based only on behavioral examinations. The increasing use of neuroimaging techniques allows improving clinical characterization of these patients. Recent neuroimaging studies using positron emission tomography, functional magnetic resonance imaging, electroencephalography and transcranial magnetic stimulation can help assess diagnosis, prognosis, and therapeutic treatment. These techniques, using resting state, passive and active paradigms, also highlight possible dissociations between consciousness and responsiveness, and are facilitating a more accurate understanding of brain function in this challenging population.

The vegetative state: prevalence, misdiagnosis, and treatment limitations

INTRODUCTION

Patients in a vegetative state/unresponsive wakefulness syndrome (VS/UWS) open their eyes spontaneously, but show only reflexive behavior. Although VS/UWS is one of the worst possible outcomes of acquired brain injury, its prevalence is largely unknown. This study's objective was to map the total population of hospitalized and institutionalized patients in VS/UWS in the Netherlands: prevalence, clinical characteristics, and treatment limitations.

METHODS

Nationwide point prevalence study on patients in VS/UWS at least 1 month after acute brain injury in hospitals, rehabilitation centers, nursing homes, institutions for people with intellectual disability, and hospices; diagnosis verification by a researcher using the Coma Recovery Scale-revised (CRS-r); gathering of demographics, clinical characteristics, and treatment limitations.

RESULTS

We identified 33 patients in VS/UWS, 24 of whose diagnoses could be verified. Patients were on average 51 years old with a mean duration of VS/UWS of 5 years. The main etiology was hypoxia sustained during cardiac arrest and resuscitation. More than 50% of patients had not received rehabilitation services. Most were given life-sustaining treatment beyond internationally accepted prognostic boundaries regarding recovery of consciousness. Seventeen (39%) of 41 patients presumed to be in VS/UWS were found to be at least minimally conscious.

CONCLUSIONS

Results translate to a prevalence of 0.1 to 0.2 hospitalized and institutionalized VS/UWS patients per 100,000 members of the general population. This small figure may be related to the legal option to withhold or withdraw life-sustaining treatment, including artificial nutrition and hydration. On the other hand, this study shows that in certain cases, physicians continue life-prolonging treatment for up to 25 years. Patients have poor access to rehabilitation and are at substantial risk for misdiagnosis.

Effectiveness of Sensory Stimulation to Improve Arousal and Alertness of People in a Coma or Persistent Vegetative State After Traumatic Brain Injury: A Systematic Review

OBJECTIVE. This systematic review evaluates the effectiveness of sensory stimulation to improve arousal and alertness of people in a coma or persistent vegetative state after traumatic brain injury (TBI).

METHOD. Databases searched included Medline, PsycINFO, CINAHL, OTseeker, and the Cochrane Database of Systematic Reviews. The search was limited to outcomes studies published in English in peer-reviewed journals between 2008 and 2013.

RESULTS. Included studies provide strong evidence that multimodal sensory stimulation improves arousal and enhances clinical outcomes for people in a coma or persistent vegetative state after TBI. Moderate evidence was also provided for auditory stimulation, limited evidence was provided for complex stimuli, and insufficient evidence was provided for median nerve stimulation.

CONCLUSION. Interventions should be tailored to client tolerance and premorbid preferences. Bimodal or multimodal stimulation should begin early, be frequent, and be sustained until more complex activity is possible.

Technology-aided programs for post-coma patients emerged from or in a minimally conscious state

Post-coma persons in a minimally conscious state (MCS) or emerged/emerging from such state (E-MCS), who are affected by extensive motor impairment and lack of speech, may develop an active role and interact with their environment with the help of technology-aided intervention programs. Although a number of studies have been conducted in this area during the last few years, new evidence about the efficacy of those programs is warranted. These three studies were an effort in that direction. Study I assessed a technology-aided program to enable six MCS participants to access preferred environmental stimulation independently. Studies II and III assessed technology-aided programs to enable six E-MCS participants to make choices. In Study II, three of those participants were led to choose among leisure and social stimuli, and caregiver interventions automatically presented to them. In Study III, the remaining three participants were led to choose (a) among general stimulus/intervention options (e.g., songs, video-recordings of family members, and caregiver interventions); and then (b) among variants of those options. The results of all three studies were largely positive with substantial increases of independent stimulation access for the participants of Study I and independent choice behavior for the participants of Studies II and III. The results were analyzed in relation to previous data and in terms of their implications for daily contexts working with MCS and E-MCS persons affected by multiple disabilities.

Measuring consciousness in severely damaged brains

Significant advances have been made in the behavioral assessment and clinical management of disorders of consciousness (DOC). In addition, functional neuroimaging paradigms are now available to help assess consciousness levels in this challenging patient population. The success of these neuroimaging approaches as diagnostic markers is, however, intrinsically linked to understanding the relationships between consciousness and the brain. In this context, a combined theoretical approach to neuroimaging studies is needed. The promise of such theoretically based markers is illustrated by recent findings that used a perturbational approach to assess the levels of consciousness. Further research on the contents of consciousness in DOC is also needed.

Occupation and communication programs for post-coma persons with or without consciousness disorders who show extensive motor impairment and lack of speech

These two studies were aimed at extending the assessment of technology-aided programs for post-coma persons with extensive motor impairment and lack of speech. Specifically, Study I assessed a new program arrangement, in which stimulation access and caregiver attention could be obtained with variations of the same response (i.e., single- versus double-hand closure) by three participants who were diagnosed at the upper level of the minimally conscious state at the start of the study. Study II was aimed at enabling two persons who had emerged from a minimally conscious state to engage in leisure activities, listen to audio-recordings of family members, and send and receive messages. The responses selected for these participants were hand pressure and eyelid closure, respectively. The results of both studies were positive. The participants of Study I increased their responding to increase their stimulation input and caregiver interaction. The participants of Study II managed to successfully select all the options the program included (i.e., the leisure options, as well as the family and communication options). General implications of the programs and the related technology packages for intervention with post-coma persons with multiple disabilities are discussed.

Post-coma persons emerging from a minimally conscious state with multiple disabilities make technology-aided phone contacts with relevant partners

Post-coma individuals emerging from a minimally conscious state with multiple disabilities may enjoy contact with relevant partners (e.g., family members and friends), but may not have easy access to them. These two single-case studies assessed whether those individuals could make contact with partners through computer-aided telephone technology and enjoy such contact. The technology involved a computer system with special software, a global system for mobile communication modem (GSM), and microswitch devices. In Study I, the computer system presented a 23-year-old man the names of the partners that he could contact, one at a time, automatically. Together with each partner's name, the system also presented the voice of the partner asking the man whether he wanted to call him or her. The man could (a) place a call to that partner by activating a camera-based microswitch through mouth movements or (b) bypass that partner and wait for the next one to be presented. In Study II, the system presented a 36-year-old man the partners' names only after he had activated his wobble microswitch with a hand movement. The man could place a call or bypass a partner as in Study I. The results showed that both men (a) were able to contact relevant partners through the technology, (b) seemed to enjoy their telephone-mediated communication contacts with the partners, and (c) showed preferences among the partners. Implications of the findings are discussed.

Technology-aided recreation and communication opportunities for post-coma persons affected by lack of speech and extensive motor impairment

This study assessed technology-aided intervention programs for two post-coma men who had re-acquired consciousness, but were unable to engage in personally or socially relevant occupations, given their lack of functional speech and their extensive motor disabilities. The microswitches used for accessing the program contents consisted of (a) a pressure sensor fixed in the palm of the first man's hand that could be activated with a small hand closure movement, and (b) an optic sensor fixed under the chin of the second man that could be activated by mouth opening movements. The programs' content consisted of recreation and communication options, which involved activating music, videos, and basic requests, sending and receiving (listening to) text messages, and placing phone calls. The results showed that the men (a) used the technology-aided programs successfully to manage the recreation and communication options available and (b) showed consistent preference for the sessions with the technology-aided program over other daily events. Family and staff members interviewed about the participants' programs (seven members for each participant) thought that the participants enjoyed the intervention sessions with the programs and that the programs had beneficial effects for them. Implications of the findings are discussed.

Technology-aided leisure and communication opportunities for two post-coma persons emerged from a minimally conscious state and affected by multiple disabilities

This study assessed technology-aided programs for helping two post-coma persons, who had emerged from a minimally conscious state and were affected by multiple disabilities, to (a) engage with leisure stimuli and request caregiver's procedures, (b) send out and listen to text messages for communication with distant partners, and (c) combine leisure engagement and procedure requests with text messaging within the same sessions. The program for leisure engagement and procedure requests relied on the use of a portable computer with commercial software, and a microswitch for the participants' response. The program for text messaging communication involved the use of a portable computer, a GSM modem, a microswitch for the participants' response, and specifically developed software. Results indicated that the participants were successful at each of the three stages of the study, thus providing relevant evidence concerning performance achievements only minimally documented. The implications of the findings in terms of technology and practical opportunities for post-coma persons with multiple disabilities are discussed.

Responsiveness of Instruments to Assess Disorders of Consciousness: A Literature Review

Objectives: To summarise available evidence for responsiveness of six key assessments used with patients with disorders of consciousness: Coma Recovery Scale – Revised (CRS-R), Disorders Of Consciousness Scale (DOCS), Sensory Modality Assessment and Rehabilitation Technique (SMART), Sensory Stimulation Assessment Measure (SSAM), Wessex Head Injury Matrix (WHIM), and the Western Neuro Sensory Stimulation Profile (WNSSP).

Method: A literature search of five electronic databases was conducted using a systematic search strategy. Relevant literature was evaluated and pertinent information extracted.

Results: Database searches using key terms initially yielded 132 articles. Following review for inclusion identified 24 articles. No studies were specifically designed to investigate responsiveness of any of the measures and therefore responsiveness data were either based on statistical significance of change post-treatment or descriptive analysis of change scores. The majority of studies identified used the CRS-R (n= 11), WHIM (n= 5) and WNSSP (n= 6) and have established responsiveness to change. There is some preliminary evidence for the responsiveness of the other measures, based on very few available studies: DOCS (n= 2), SMART (n= 1) or SSAM (n= 1).

Conclusion: Future studies should seek to include responsiveness analysis, particularly in relation to the DOCS, SMART and SSAM.

Can we scientifically and reliably measure the level of consciousness in vegetative and minimally conscious States? Rasch analysis of the coma recovery scale-revised

OBJECTIVES

(1) To appraise, by the means of Rasch analysis, the internal validity and reliability of the Coma Recovery Scale-Revised (CRS-R) in a sample of patients with disorder of consciousness (DOC); and (2) to provide information about the comparability of CRS-R scores across persons with DOC across different settings and groups, including different etiologies.

DESIGN

Multicenter observational prospective study.

SETTING

Two rehabilitation wards, 1 intermediate care facility, and 2 nursing homes in Italy.

PARTICIPANTS

Consecutively admitted patients (N=129) for which assessments at 2 different time points were available, giving a total sample of 258 observations.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURE

CRS-R.

RESULTS

After controlling for any possible dependency between persons' measures collected at different time points, and for uniform differential item functioning by etiology showed by the visual subscale, Rasch analysis demonstrated adequate satisfaction of all the model's requirements, including adequate ordering of scoring categories, unidimensionality, local independence, invariance (χ(2)21=27.798, P=.146), and absence of differential item functioning across patients' sex, age, time, and setting. The reliability (person separation index=.896) was adequate for individual person measurement. We devised a practical raw score to measure conversion tables based on the CRS-R calibrations.

CONCLUSIONS

The CRS-R is a psychometrically sound and robust measurement tool. The linear measures of ability derived from the CRS-R total scores do satisfy all the principles of scientific measurement and are sufficiently reliable for high stakes assessments, such as the diagnosis of the level of consciousness in individual patients. Future studies are needed to directly explore the capabilities of the CRS-R measures to reduce the risk of vegetative state misdiagnosis.

Promoting adaptive behavior in persons with acquired brain injury, extensive motor and communication disabilities, and consciousness disorders

These two studies extended the evidence on the use of technology-based intervention packages to promote adaptive behavior in persons with acquired brain injury and multiple disabilities. Study I involved five participants in a minimally conscious state who were provided with intervention packages based on specific arrangements of optic, tilt, or pressure microswitches (linked to preferred environmental stimuli) and eyelid, toe and finger responses. Study II involved three participants who were emerging from a minimally conscious state and were provided with intervention packages based on computer presentations of stimulus options (i.e., preferred stimuli, functional caregiver's procedures, and non-preferred stimuli) and pressure microswitches to choose among them. Intervention data of Study I showed that the participants acquired relatively high levels of microswitch responding (thus engaging widely with preferred environmental stimuli) and kept that responding consistent except for one case. Intervention data of Study II showed that the participants were active in choosing among preferred stimuli and positive caregivers' procedures, but generally abstained from non-preferred stimuli. The results were discussed in terms of the successful use of fairly new/infrequent microswitch-response arrangements (Study I) and the profitable inclusion of functional caregiver's procedures among the options available to choice (Study II).