Validation of the Italian version of the Coma Recovery Scale-Revised (CRS-R)

Family caregivers improve the diagnostic accuracy of disorders of consciousness: from remote to near-bed auditory stimulation

BACKGROUND

Family caregivers (FC) contribute to reducing the misdiagnosis rate in patients with disorders of consciousness (DOC). Unfortunately, the recent pandemic of COVID-19 imposed drastic restrictions that limited the access of FC to the sensory/cognitive stimulation protocols. Telemedicine approaches have been implemented to avoid discontinuity in care pathways and to ensure caregivers involvement in rehabilitation programs.

AIM

The aim was to investigate whether the presence of FC remotely connected might help clinicians in eliciting higher cortically mediated behavioral responses in patients with DOC.

DESIGN

Cross-sectional study.

SETTING

Post-acute Unit of Neurorehabilitation.

POPULATION

DOC due to severe brain injury.

METHODS

Consecutive patients with DOC were assessed by means of the Coma Recovery Scale-Revised (CRS-R) by two expert examiners. Each patient underwent to five assessments in two weeks in three different conditions: 1) by the examiner only (standard); 2) with the verbal stimulation given by the FC remotely connected by PC tablet (caregiver in remote); and 3) with the verbal stimulation given by the FC physically present (caregiver in presence).

RESULTS

Thirty patients with DOC (VS/UWS=10; MCS=20; mean age: 51, range: 21-79; vascular: 16; anoxic: 6; TBI=8) and their FC were enrolled. Higher total scores of CRS-R were recorded both in "caregiver in remote" and in "caregiver in presence" than in standard condition (standard vs. remote, Z=2.942, P=0.003; standard vs. presence, Z=3.736, P<0.001). Furthermore, the administration of the CRS-R with a FC, elicited higher levels of behavioral responses in MCS patients, than CRS-R performed in standard condition. In particular, 2 patients out of 30 (6.66%) showed higher scores and better diagnosis when the CRS-R was administered with FC in remote. Similarly, 5 out of 30 patients (16.66%) showed better diagnoses when the CRS-R was administered with FC in presence. Five patients changed diagnosis between standard and presence conditions (3 MCS- were diagnosed as MCS+; 2 MCS+ were diagnosed as conscious).

CONCLUSIONS

Our findings add new evidence regarding the beneficial role of family members in the diagnosis of DOC, even mediated by telemedicine approach.

CLINICAL REHABILITATION IMPACT

In future guidelines, FC should have an active and supporting role in the diagnostic and rehabilitative process of DOC.

Reliability and validation of the Japanese version of the coma recovery scale-revised (CRS-R)

PRIMARY OBJECTIVE

This study aimed to verify the reliability and validity of the Japanese version of the Coma Recovery Scale-Revised (CRS-R).

METHODS

Subjects included 59 patients with disorders of consciousness (DOC) due to acquired brain injury. To validate test-retest reliability, Evaluator A assessed the CRS-R twice on the same day (A1, A2). To examine inter-rater reliability, Evaluators A (A2) and B (B) assessed the CRS-R without a time interval. To test concurrent validity, Evaluator A (A1) assessed the CRS-R, Japan Coma Scale (JCS), and the Glasgow Coma Scale (GCS) consecutively. To validate diagnostic accuracy, we evaluated the degree of agreement between A1 and A2 and between A2 and B in their diagnosis of DOC by CRS-R.

RESULTS

The test-retest (ρ = 0.92) and inter- (ρ = 0.98) reliability of CRS-R were excellent" and Concurrent validity of CRS-R with JCS (ρ =  -0.82) and GCS (ρ = 0.92) were high. Results of DOC diagnosis were consistent for 48/59 cases (κ = 0.82) for A1 and A2 and for 54/59 cases (κ = 0.92) for A2 and B.

CONLCUSION

The Japanese version of the CRS-R may be as reliable and valid as the original English and other language versions.

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.

Classification of Level of Consciousness in a Neurological ICU Using Physiological Data

BACKGROUND

Impaired consciousness is common in intensive care unit (ICU) patients, and an individual's degree of consciousness is crucial to determining their care and prognosis. However, there are no methods that continuously monitor consciousness and alert clinicians to changes. We investigated the use of physiological signals collected in the ICU to classify levels of consciousness in critically ill patients.

METHODS

We studied 61 patients with subarachnoid hemorrhage (SAH) and 178 patients with intracerebral hemorrhage (ICH) from the neurological ICU at Columbia University Medical Center in a retrospective observational study of prospectively collected data. The level of consciousness was determined on the basis of neurological examination and mapped to comatose, vegetative state or unresponsive wakefulness syndrome (VS/UWS), minimally conscious minus state (MCS-), and command following. For each physiological signal, we extracted time-series features and performed classification using extreme gradient boosting on multiple clinically relevant tasks across subsets of physiological signals. We applied this approach independently on both SAH and ICH patient groups for three sets of variables: (1) a minimal set common to most hospital patients (e.g., heart rate), (2) variables available in most ICUs (e.g., body temperature), and (3) an extended set recorded mainly in neurological ICUs (absent for the ICH patient group; e.g., brain temperature).

RESULTS

On the commonly performed classification task of VS/UWS versus MCS-, we achieved an area under the receiver operating characteristic curve (AUROC) in the SAH patient group of 0.72 (sensitivity 82%, specificity 57%; 95% confidence interval [CI] 0.63-0.81) using the extended set, 0.69 (sensitivity 83%, specificity 51%; 95% CI 0.59-0.78) on the variable set available in most ICUs, and 0.69 (sensitivity 56%, specificity 78%; 95% CI 0.60-0.78) on the minimal set. In the ICH patient group, AUROC was 0.64 (sensitivity 56%, specificity 65%; 95% CI 0.55-0.74) using the minimal set and 0.61 (sensitivity 50%, specificity 80%; 95% CI 0.51-0.71) using the variables available in most ICUs.

CONCLUSIONS

We find that physiological signals can be used to classify states of consciousness for patients in the ICU. Building on this with intraday assessments and increasing sensitivity and specificity may enable alarm systems that alert physicians to changes in consciousness and frequent monitoring of consciousness throughout the day, both of which may improve patient care and outcomes.

Behavioral Assessment of Patients with Disorders of Consciousness

Severe brain injury is associated with a period of impaired level of consciousness that can last from days to months and results in chronic impairment. Systematic assessment of level of function in patients with disorders of consciousness (DoC) is critical for diagnosis, prognostication, and evaluation of treatment efficacy. Approximately 40% of patients who are thought to be unconscious based on clinical bedside behavioral assessment demonstrate some signs of consciousness on standardized behavioral assessment. This finding, in addition to a growing body of literature demonstrating the advantages of standardized behavioral assessment of DoC, has led multiple professional societies and clinical guidelines to recommend standardized assessment over routine clinical evaluation of consciousness. Nevertheless, even standardized assessment is susceptible to biases and misdiagnosis, and examiners should consider factors, such as fluctuating arousal and aphasia, that may confound evaluation. We review approaches to behavioral assessment of consciousness, recent clinical guideline recommendations for use of specific measures to evaluate patients with DoC, and strategies for mitigating common biases that may confound the examination.

EEG Power spectra and subcortical pathology in chronic disorders of consciousness

BACKGROUND

Despite a growing understanding of disorders of consciousness following severe brain injury, the association between long-term impairment of consciousness, spontaneous brain oscillations, and underlying subcortical damage, and the ability of such information to aid patient diagnosis, remains incomplete.

METHODS

Cross-sectional observational sample of 116 patients with a disorder of consciousness secondary to brain injury, collected prospectively at a tertiary center between 2011 and 2013. Multimodal analyses relating clinical measures of impairment, electroencephalographic measures of spontaneous brain activity, and magnetic resonance imaging data of subcortical atrophy were conducted in 2018.

RESULTS

In the final analyzed sample of 61 patients, systematic associations were found between electroencephalographic power spectra and subcortical damage. Specifically, the ratio of beta-to-delta relative power was negatively associated with greater atrophy in regions of the bilateral thalamus and globus pallidus (both left > right) previously shown to be preferentially atrophied in chronic disorders of consciousness. Power spectrum total density was also negatively associated with widespread atrophy in regions of the left globus pallidus, right caudate, and in the brainstem. Furthermore, we showed that the combination of demographics, encephalographic, and imaging data in an analytic framework can be employed to aid behavioral diagnosis.

CONCLUSIONS

These results ground, for the first time, electroencephalographic presentation detected with routine clinical techniques in the underlying brain pathology of disorders of consciousness and demonstrate how multimodal combination of clinical, electroencephalographic, and imaging data can be employed in potentially mitigating the high rates of misdiagnosis typical of this patient cohort.

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.

Translation and Transcultural Adaptation of the Wessex Head Injury Matrix, Italian Version: A Preliminary Report

Background: Patients who are in a coma, a vegetative state or a minimally conscious state present a clinical challenge for neurological assessment, which is a prerequisite for establishing a prognosis and planning management. Several scales have been developed to evaluate these patients. The Wessex Head Injury Matrix is a comprehensive tool but is currently available only in the French and English languages. The aim of this study was to translate and evaluate the reliability of the Italian version of the scale. Methods: The original scale was translated according to a standard protocol: three separate translations were made, and a selected version was back-translated to check for any errors in order to obtain the most accurate Italian translation. A final back translation of the agreed version was made as a further check. The final version was then administered blind to a consecutive series of patients with severe acquired brain injury by two examiners. Inter-rater and test-retest reliability were assessed using a weighted Cohen’s kappa (Kw). Concurrent validity of the WHIM was evaluated by ρ Spearman’s correlation coefficient using the Glasgow Coma Scale (GCS) and the Coma Recovery Scale Revised (CRS-R) as the available gold standard. Results: Twenty-four patients (12 males and 12 females; mean age 59.9 ± 20.1; mean duration from index event 17.7 ± 20.0 days) with stroke (n = 15), traumatic brain injury (n = 7) and anoxic encephalopathy (n = 2) were included. Inter-rater [Kw 0.80 (95% CI 0.75–0.84)] and test-retest reliability [Kw 0.77 (95% CI 0.72–0.81)] showed good values. WHIM total scores correlated significantly with total scores on the GCS (ρ = 0.776; p < 0.001) and the CRS-R (ρ = 0.881; p < 0.001) demonstrating concurrent validity; Conclusion: The Italian version of the scale is now available for clinical practice and research.

[The Russian version of Coma Recovery Scale-revised - a standardized method for assessment of patients with disorders of consciousness]

The authors officially present for the first time the Russian version of Coma Recovery Scale-Revised (CRS-R). Today CRS-R is the only validated scale in Russian for assessment of patients with chronic disorders of consciousness (DOC). The study showed high consistency for different researchers, high sensitivity in the evaluation of patients over time as well as high concurrent validity. This article contains the text of the scale and recommendations how to use CRS-R and interpret the data. Presented version of the CRS-R is recommended for use in DOC patients. Russian version of the CRS-R is a standardized, comprehensive and systematic approach to the examination and assessment of patients with chronic DOS. It ensures the standard approach to examination and assessment that warrants the accuracy and homogeneity of the obtained results.

Validation of the Chinese version of the Coma Recovery Scale-Revised (CRS-R)

PRIMARY OBJECTIVE

This study aims to validate the Chinese version of the Coma Recovery Scale-Revised (CRS-R).

METHODS

One hundred sixty-nine patients were assessed with both the CRS-R and the Glasgow Coma Scale (GCS), diagnosed as being in unresponsive wakefulness syndrome (UWS, formerly known as vegetative state), minimally conscious state (MCS), or emergence from MCS (EMCS). A subgroup of 50 patients has been assessed twice by the same rater, within 24 h. Patient outcome was documented six months after assessment.

RESULTS

The internal consistency for the CRS-R total score was excellent (Cronbach's α = 0.84). Good test-retest reliability was obtained for CRS-R total score and subscale scores (intra-class correlation coefficient [ICC] = 0.87 and ICC = 0.66-0.84, respectively). Inter-rater reliability was high (ICC = 0.719; p < 0.01). Concurrent validity was good between CRS-R total scale and GCS total scale. Diagnostic validity was excellent compared with GCS (emerged from UWS: 24%; emerged from MCS: 28%). When considering patient outcome, diagnostic validity was good. In addition, false-positive rates have been detected for both diagnoses.

CONCLUSION

The Chinese version of the CRS-R is a reliable and sensitive tool and can discriminate patients in UWS, MCS, and EMCS successfully.

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.

A Russian validation study of the Coma Recovery Scale-Revised (CRS-R)

INTRODUCTION

The aim of the study was to develop and validate a Russian adaptation of the Coma Recovery Scale-Revised (CRS-R).

SUBJECTS AND METHODS

We evaluated 58 patients with chronic disorders of consciousness (> 4 weeks post-injury, DOC) of various etiology and two patients in a locked-in state at different stages after coma. We tested sensitivity for changes over 1 week, reliability, criterion validity and diagnostic sensitivity of the Russian adaptation of the CRS-R in comparison with the Russian adaptations of Full Outline of UnResponsiveness Score (FOUR), and Glasgow Coma Scale (GCS).

RESULTS

We obtained good sensitivity for changes in neurological status over week (p < 0.0001) and good test-retest reliability (r = 0.997, p < 0.0001) of the CRS-R. Inter-rater reliability was good (κ = 0.99, p < 0.001). We showed high internal consistency (α = 0.87) of the scale and good criterion validity between other scales (r = 0.597 for GCS, and r = 0.900 for FOUR). CRS-R also demonstrated a higher sensitivity in differential diagnosis of DOC, as compared to GCS, and FOUR Score (p < 0.001).

CONCLUSION

The results show that the Russian version of the CRS-R is a valid and sensitive tool for the evaluation of patients with chronic DOC, which can be used for differential diagnosis and for recovery assessment.

Do Sensory Stimulation Programs Have an Impact on Consciousness Recovery?

Objectives: Considering sensory stimulation programs (SSP) as a treatment for disorders of consciousness is still debated today. Previous studies investigating its efficacy were affected by various biases among which small sample size and spontaneous recovery. In this study, treatment-related changes were assessed using time-series design in patients with disorders of consciousness (i.e., vegetative state-VS and minimally conscious state-MCS). Methods: A withdrawal design (ABAB) was used. During B phases, patients underwent a SSP (3 days a week, including auditory, visual, tactile, olfactory, and gustatory stimulation). The program was not applied during A phases. To assess behavioral changes, the Coma Recovery Scale-Revised (CRS-R) was administered by an independent rater on a weekly basis, across all phases. Each phase lasted 4 weeks. In a subset of patients, resting state functional magnetic resonance imaging (fMRI) data were collected at the end of each phase. Results: Twenty nine patients (48 ± 19 years old; 15 traumatic; 21 > a year post-injury; 11 VS and 18 MCS) were included in our study. Higher CRS-R total scores (medium effect size) as well as higher arousal and oromotor subscores were observed in the B phases (treatment) as compared to A phases (no treatment), in the MCS group but not in the VS group. In the three patients who underwent fMRI analyses, a modulation of metabolic activity related to treatment was observed in middle frontal gyrus, superior temporal gyrus as well as ventro-anterior thalamic nucleus. Conclusion: Our results suggest that SSP may not be sufficient to restore consciousness. SSP might nevertheless lead to improved behavioral responsiveness in MCS patients. Our results show higher CRS-R total scores when treatment is applied, and more exactly, increased arousal and oromotor functions.

Validation of Korean Version of Coma Recovery Scale-Revised (K-CRSR)

Objective

To determine the validity and reliability of the Korean version of the Coma Recovery Scale-Revised (K-CRSR) for evaluation of patients with a severe brain lesion.

Methods

With permission from Giacino, the developer of the Coma Recovery Scale Revised (CRSR), the scale was translated into Korean and back-translated into English by a Korean physiatrist highly proficient in English, and then verified by the original developer. Adult patients with a severe brain lesion following traumatic brain injury, stroke, or hypoxic brain injury were examined. To assess the inter-rater reliability, all patients were tested with K-CRSR by two physiatrists individually. To determine intra-rater reliability, the same test was re-administered by the same physiatrists after three days.

Results

Inter-rater reliability (k=0.929, p<0.01) and intra-rater reliability (k=0.938, p<0.01) were both high for total K-CRSR scores. Inter- and intra-rater agreement rates were very high (94.9% and 97.4%, respectively). The total K-CRSR score was significantly correlated with K-GCS (r=0.894, p<0.01), demonstrating sufficient concurrent validity.

Conclusion

K-CRSR is a reliable and valid instrument for the assessment of patients with brain injury by trained physiatrists. This scale is useful in differentiating patients in minimally conscious state from those in vegetative state.

Early rehabilitation of Disorders of Consciousness (DOC): management, neuropsychological evaluation and treatment

In order to ensure the best possible rehabilitation plan and best outcome for patients with Disorders of Consciousness (DOC), optimal management of the early phase of rehabilitation is fundamental. This includes a correct diagnosis, accurate assessment of the patient's state of alertness and the main comorbidities, appropriate neurophysiological and neuroradiology examinations, and education of the caregiver and family so that they can provide the best assistance. Thirty years ago, specialists first began applying a systematic approach to the rehabilitation of patients with DOC, but still today many problems remain unsolved: the rate of misdiagnosis is still high, and recommendations about the most appropriate mode of rehabilitation are lacking, both as regards the timing of interventions and what the best techniques to use are. In a medical sector where nosography has changed over the last decade and where the documented evidence, though increasing, still remains insufficient, we discuss in this brief review the main assessment tools and disability scales to use and the key issues that need to be considered when a patient with DOC is admitted to the rehabilitation unit and decisions about the early rehabilitation plan are made.

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.

A validation of the Polish version of the Coma Recovery Scale-Revised (CRSR)

PRIMARY OBJECTIVE

The aim of this study was to determine the validity of the Polish version of the Coma Recovery Scale-Revised (CRS-R).

METHODS AND DESIGN

Two trained raters, A and B, administered CRS-R on a group of 20 patients with severe brain injury (median age ± SD, 38.0 ± 14.39 years). Both rater A and rater B completed their assessment on day 1, and rater A repeated their assessment on day 2. Inter-rater and test-retest reliability were evaluated with an intra-class correlation coefficient and Spearman rank correlation. Internal consistency was estimated with Cronbach's α. Agreement in diagnostic impression was determined using Cohen's κ.

RESULTS

Inter-rater reliability for CRS-R total scores and test-retest reliability was excellent: (ρ = 0.76, p < 0.001) and (ρ = 0.92, p < 0.001), respectively. Inter-rater diagnostic agreement was good (κ = 0.72, p < 0.001). Inter-rater reliability for subscales was fair to excellent. Internal consistency was excellent (Cronbach's α = 0.85).

CONCLUSION

The Polish version of CRS-R can be administered reliably by trained raters and can successfully differentiate between vegetative state (VS), minimally conscious (MCS), and patients emerging from a minimally conscious state (EMCS).

Functional Networks in Disorders of Consciousness

Severe brain injury may cause disruption of neural networks that sustain arousal and awareness, the two essential components of consciousness. Despite the potentially devastating immediate and long-term consequences, disorders of consciousness (DoC) are poorly understood in terms of their underlying neurobiology, the relationship between pathophysiology and recovery, and the predictors of treatment efficacy. Recent advances in neuroimaging techniques have enabled the study of network connectivity, providing great potential to improve the clinical care of patients with DoC. Initial discoveries in this field were made using positron emission tomography (PET). More recently, functional magnetic resonance (fMRI) techniques have added to our understanding of functional network dynamics in this population. Both methods have shown that whether at rest or performing a goal-oriented task, functional networks essential for processing intrinsic thoughts and extrinsic stimuli are disrupted in patients with DoC compared with healthy subjects. Atypical connectivity has been well established in the default mode network as well as in other cortical and subcortical networks that may be required for consciousness. Moreover, the degree of altered connectivity may be related to the severity of impaired consciousness, and recovery of consciousness has been shown to be associated with restoration of connectivity. In this review, we discuss PET and fMRI studies of functional and effective connectivity in patients with DoC and suggest how this field can move toward clinical application of functional network mapping in the future.

Chinese translation of the Coma Recovery Scale-Revised

BACKGROUND

Misdiagnosis rate is high in patients with disorders of consciousness, potentially leading to an inappropriate clinical management of these patients. Sensitive standardised rating scales offer some protections from these diagnostic errors. In this context, the use of the Coma Recovery Scale-Revised (CRS-R) has strongly been recommended by the American Congress of Rehabilitation Medicine.

OBJECTIVE

Here, we present the work that has been performed to translate this important diagnostic tool in Chinese.

METHODS

The scale has been translated from its original English version to Chinese by a team of native Chinese speakers in agreement with an expert highly trained in the use of the original version of the CRS-R and, then, back-translated to English by four independent translators blinded to the original version. The resulting translation has been sent to the original author for final approval.

RESULTS AND CONCLUSION

The Chinese version of the CRS-R is now available for use in clinical practise. Further investigations will nevertheless be needed in order to show that its psychometric properties are identical to the original English version.

Do you see me? The role of visual fixation in chronic disorders of consciousness differential diagnosis

Visual fixation (VF) of a target is a possible, although atypical, feature of the Unresponsive Wakefulness Syndrome (UWS). Whether VF may indicate residual awareness in these patients is debatable, since it may simply subtend a series of reflex processes. Objective tools should therefore be used to identify aware VF, which depends on the integrity of visuomotor networks encompassing frontal-parietal-occipital areas. The aim of our study was to detect residual visuomotor network functionality potentially sustaining aware VF. To this end, we evaluated the visuomotor integration (VMI) and visual P300 patterns in a chronic Disorder of Consciousness (DOC) sample and a control group of healthy individuals (HC), using an associative stimulation protocol combining transcranial magnetic stimulation (TMS) with visual stimulation through transorbital alternating current stimulation. The Minimally Conscious State (MCS) patients showed preserved patterns of VMI and P300, whereas nearly all the UWS patients showed no significant VMI. Notably, the electrophysiological findings were correlated with the visual domain of the Coma Recovery Scale-Revised. Nonetheless, two fixating UWS individuals had a VMI similar to MCS patients. Our data suggest that some UWS patients showing VF could be aware, but unable to manifest it clearly, probably because of a severe motor output impairment, which is a condition compatible with the Functional Locked-In Syndrome.

Morfeo Study II: Clinical Course and Complications in Patients With Long-Term Disorders of Consciousness

BACKGROUND

The life expectancy of patients with disorders of consciousness (DOCs) is ever-increasing, but little is known about their clinical course over late stages. Several issues (premorbid conditions, complications and pressure sores) are to be considered for their effect on clinical outcome, risk of death and recovery of functional performance. Unfortunately, in late stages of long-term rehabilitation, these aspects are still more neglected than in acute and postacute stages. The aim of this study was to investigate the clinical course and the complications of patients in the late stages of DOCs and to explore the relationship between mortality and specific biomarkers.

MATERIALS AND METHODS

A total of 112 patients, admitted over 10 years in a dedicated ward, were retrospectively studied. Sociodemographic data, preadmission and inpatient clinical features were collected. Disability Rating Scale scores, complications including pressure sores and blood markers were assessed monthly. Data were analyzed through descriptive statistics and correlations using SPSS.

RESULTS

Most patients were men older than 50 years with a nontraumatic etiology and a history of hypertension (42.86%). The most common complication was pneumonia (76.79%). No association was found between sex and mortality or between etiology and mortality (P > 0.05). Mortality correlated significantly with sepsis (ρ = 0.253), albumin (ρ = -0.558), hemoglobin (ρ = -0.354) and white blood cells (ρ = 0.243). Only 42% of patients remained unchanged at Disability Rating Scale evaluation.

CONCLUSIONS

These data confirmed that DOCs are not static conditions and they require ongoing monitoring and assessment of clinical status, level of consciousness and laboratory biomarkers.

ICF-DOC: the ICF dedicated checklist for evaluating functioning and disability in people with disorders of consciousness

Clinicians need a comprehensive description of patients' functioning state to capture the complex interaction between symptoms and environmental factors, and to determine the actual level of functioning in patients in a vegetative state or a minimally conscious state. The aim of this study is to develop an International Classification of Functioning, Disability, and Health (ICF) checklist for patients with disorders of consciousness (DOC) so as to capture and describe, with a tailored list of categories, the most common health, disability, and functioning issues of adult patients with DOC. The WHO ICF checklist was used as a basis for collecting data. This was an observational, cross-sectional, multicenter study conducted in 69 Italian centers. Specific methodological procedures were used to identify the most appropriate categories for DOC patients to be added to or deleted from the ICF checklist so as to develop the ICF-DOC checklist. A total of 566 adult patients were enrolled: 398 in a vegetative state and 168 in a minimally conscious state. A total of 127 ICF categories reached the threshold of 20% concerning the presence of a problem: 37 categories from the body functions chapter, 13 from the body structures chapter, 46 from the activities and participations chapter, and 31 from the environmental factors chapter. ICF categories identified in this study can be useful guidelines for clinicians and researchers to collect data on functioning and disability of adult patients with DOC. The new ICF-DOC checklist allows monitoring of the effects of interventions on functional areas and possible changes in each patient in follow-up studies.

Comorbidities: a key issue in patients with disorders of consciousness

The aim of this study was to identify the impact of comorbidities on outcomes of patients with vegetative state (VS) or minimally conscious state (MCS). All patients in VS or MCS consecutively admitted to two postacute care units within a 1-year period were evaluated at baseline and at 6 months through the Coma Recovery Scale-Revised Version and the Disability Rating Scale (DRS). Comorbidities were also recorded for each patient along the same period. Six-month outcomes included death, full recovery of consciousness, and functional improvement. One hundred and thirty-nine patients (88 male and 51 female; median age, 59 years) were included. Ninety-seven patients were in VS (70%) and 42 in MCS (30%). At 6 months, 33 patients were dead (24%), 39 had a full recovery of consciousness (28%), and 67 remained in VS or MCS (48%). According to DRS scores, 40% of patients (n=55) showed a functional improvement in the level of disability. One hundred and thirty patients (94%) showed at least one comorbidity. Severity of comorbidities (hazard ratio [HR]=2.8; 95% confidence interval [CI], 1.71-4.68; p<0.001) and the presence of ischemic or organic heart diseases (HR=2.6; 95% CI, 1.21-5.43; p=0.014) were the strongest predictors of death, together with increasing age (HR=1.0; 95% CI, 1.0-1.06; p=0.033). Respiratory diseases and arrhythmias without organic heart diseases were negative predictors of full recovery of consciousness (odds ratio [OR]=0.3; 95% CI, 0.12-0.7; p=0.006; OR=0.2; 95% CI, 0.07-0.43; p<0.001) and functional improvement (OR=0.4; 95% CI, 0.15-0.85, p=0.020; OR=0.2; 95% CI, 0.08-0.45; p<0.001). Our data show that comorbidities are common in these patients and some of them influence recovery of consciousness and outcomes.

The perception of pain and its management in disorders of consciousness

One of the most controversial issues in the management of patients in a vegetative state or a minimally conscious state concerns their hypothetical capacity to continue to experience pain despite an apparent absence of self- and environmental awareness. Recent functional neuroimaging studies have shown a greater perception of pain in patients in minimally conscious state compared with patients in vegetative state, suggesting the possible involvement of preserved cognitive mechanisms in the process of pain modulation in the former. In addition, a subgroup of patients might continue to experience some elementary emotional and affective feelings, as suggested by the reported activation of specific cerebral areas in response to situations, which commonly generate empathy. However, the available evidence is not sufficient to draw conclusions about the presence or absence of pain experience in patients with disorders of consciousness. Future studies should contribute to a better understanding of which central neural pathways are involved in the perception and modulation of pain in healthy subjects and in patients with severe brain injuries. Such studies should thus also improve our know-how about pain management in this particularly challenging group of patients.

Corticomotor facilitation in vegetative state: results of a pilot study

OBJECTIVE

To investigate whether corticomotor facilitation induced by transcranial magnetic stimulation (TMS-CF) could evoke a simple purposeful motor behavior in patients with a diagnosis of vegetative state.

DESIGN

Cross-sectional survey.

SETTING

Post-coma and rehabilitation care unit.

PARTICIPANTS

Patients (N=6) with a diagnosis of vegetative state.

INTERVENTIONS

A cascade of consecutive motor-evoked potentials (MEPs) was elicited under 3 different conditions: in the first condition, patients were at rest (Rest); in the second, they were asked to open and close the right hand (Execution); in the third, the examiner modeled a movement of abduction of the thumb in front of the patient who was encouraged in advance to imitate the action (Observation to Imitate).

MAIN OUTCOME MEASURES

Changes in MEP values from the abductor pollicis brevis muscle and improvement in scores on the Coma Recovery Scale-Revised.

RESULTS

TMS-CF alone or combined with verbal instructions did not yield any change; only the combination with imitation caused changes in MEPs (shorter latency and increased amplitude) associated with behavioral improvement in 4 patients.

CONCLUSIONS

Encouraging observation to imitate may favor the transformation of some perceived actions into motor images and performances, probably depending on the activation of mirror motor neurons. In our opinion, combining visual input with TMS-CF might have reinforced the coupling between movement planning and execution, promoting the recovery of elementary motor activities in some patients. The proposed protocol may contribute to unmasking signs of preserved consciousness in patients with latent capacities for recovery.

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.

A learning assessment procedure as a test supplement for monitoring progress with two post-coma persons with a diagnosis of vegetative state

OBJECTIVE

Evaluating a learning assessment procedure for monitoring progress with two post-coma adults with a diagnosis of vegetative state.

METHOD

ABABCBCB and ABABCB designs were used for the two participants, with A representing baseline, B intervention and C control conditions. Participants' activation of an optic microswitch by eyelid closure produced stimulation during B phases.

RESULTS

One participant increased responding during B phases and decreased it during the C condition, suggesting a non-reflective minimal level of consciousness. She showed P300 and mismatch negativity responses and scored at the vegetative level on the Coma Recovery Scale-Revised (CRS-R). The other participant increased responding during the initial B phases without decline during the first (viable) part of the C condition, suggesting a pre-conscious level. He showed indistinct P300 and mismatch negativity responses and vegetative-level scores on the CRS-R.

CONCLUSION

Learning data seemed reconcilable with neurophysiological measures and more positive than CRS-R scores.