Predictors of short-term outcome in brain-injured patients with disorders of consciousness

Establishment and validation of a bad outcomes prediction model based on EEG and clinical parameters in prolonged disorder of consciousness

Objective

This study aimed to explore the electroencephalogram (EEG) indicators and clinical factors that may lead to poor prognosis in patients with prolonged disorder of consciousness (pDOC), and establish and verify a clinical predictive model based on these factors.

Methods

This study included 134 patients suffering from prolonged disorder of consciousness enrolled in our department of neurosurgery. We collected the data of sex, age, etiology, coma recovery scales (CRS-R) score, complications, blood routine, liver function, coagulation and other laboratory tests, resting EEG data and follow-up after discharge. These patients were divided into two groups: training set (n = 107) and verification set (n = 27). These patients were divided into a training set of 107 and a validation set of 27 for this study. Univariate and multivariate regression analysis were used to determine the factors affecting the poor prognosis of pDOC and to establish nomogram model. We use the receiver operating characteristic (ROC) and calibration curves to quantitatively test the effectiveness of the training set and the verification set. In order to further verify the clinical practical value of the model, we use decision curve analysis (DCA) to evaluate the model.

Result

The results from univariate and multivariate logistic regression analyses suggested that an increased frequency of occurrence microstate A, reduced CRS-R scores at the time of admission, the presence of episodes associated with paroxysmal sympathetic hyperactivity (PSH), and decreased fibrinogen levels all function as independent prognostic factors. These factors were used to construct the nomogram. The training and verification sets had areas under the curve of 0.854 and 0.920, respectively. Calibration curves and DCA demonstrated good model performance and significant clinical benefits in both sets.

Conclusion

This study is based on the use of clinically available and low-cost clinical indicators combined with EEG to construct a highly applicable and accurate model for predicting the adverse prognosis of patients with prolonged disorder of consciousness. It provides an objective and reliable tool for clinicians to evaluate the prognosis of prolonged disorder of consciousness, and helps clinicians to provide personalized clinical care and decision-making for patients with prolonged disorder of consciousness and their families.

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.

Brain microstate spatio-temporal dynamics as a candidate endotype of consciousness

Consciousness can be defined as a phenomenological experience continuously evolving. Current research showed how conscious mental activity can be subdivided into a series of atomic brain states converging to a discrete spatiotemporal pattern of global neuronal firing. Using the high temporal resolution of EEG recordings in patients with a severe Acquired Brain Injury (sABI) admitted to an Intensive Rehabilitation Unit (IRU), we detected a novel endotype of consciousness from the spatiotemporal brain dynamics identified via microstate analysis. Also, we investigated whether microstate features were associated with common neurophysiological alterations. Finally, the prognostic information comprised in such descriptors was analysed in a sub-cohort of patients with prolonged Disorder of Consciousness (pDoC). Occurrence of frontally-oriented microstates (C microstate), likelihood of maintaining such brain state or transitioning to the C topography and complexity were found to be indicators of consciousness presence and levels. Features of left-right asymmetric microstates and transitions toward them were found to be negatively correlated with antero-posterior brain reorganization and EEG symmetry. Substantial differences in microstates' sequence complexity and presence of C topography were found between groups of patients with alpha dominant background, cortical reactivity and antero-posterior gradient. Also, transitioning from left-right to antero-posterior microstates was found to be an independent predictor of consciousness recovery, stronger than consciousness levels at IRU's admission. In conclusions, global brain dynamics measured with scale-free estimators can be considered an indicator of consciousness presence and a candidate marker of short-term recovery in patients with a pDoC.

Organizational ethics in urgent transfers of severely disabled people to intensive care units - a qualitative study

PURPOSE

Urgent transfers of severely impaired patients with chronic neurological disability (PwND) from a neurological physical and rehabilitation medicine (nPRM) to an intensive care unit (ICU) or an emergency room (ER) served as the basis for this study. We hypothesized that human and structural factors interfered with but were not directly related to the acute context.

METHODS

We decided to use a qualitative methodology, based on in-depth interviews with 16 ICU/ER physicians. We used mixed bottom-up and top-down methods. We interpreted our data using a thematic approach based on the key principles of grounded theory, which were modified with consideration of the literature.

RESULTS

Three main domains emerged. The impact of the clinical setting notably implied the patient's clinical typology between the acute event and the chronic background, but also bed availability. Key elements of the telephone negotiation were confidence and perceived usefulness of the transfer. Finally, the otherness of some categories of patients, transferred with more difficulty, involved those with cognitive impairment.

CONCLUSIONS

The existence of healthcare pathways for many years has created an organizational culture between departments of nPRM and ICUs. But urgent transfers also imply organizational ethics, as a balance should be struck between utility and equity. IMPLICATIONS FOR REHABILITATIONStructural and human factors interfere in urgent transfers, involving the settings within health pathways, the key elements of negotiation to get confidence and a perceived utility of transfer, and certain categories of people, especially those with cognitive impairment.Transfers that imply negotiation between practitioners from physical and rehabilitation medicine and intensive care unit departments, lead to a need of organizational ethics, as a balance should be struck between the principles of utility and equity.The development of facilitating tools such as a commitment charter is of paramount importance as it can support ethical decision-making.

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.

Heart rate variability for the evaluation of patients with disorders of consciousness

OBJECTIVE

Clinical responsiveness of patients with a Disorder of Consciousness (DoC) correlates to sympathetic/parasympathetic homeostatic balance. Heart Rate Variability (HRV) metrics result in non-invasive proxies of modulation capabilities of visceral states. In this work, our aim was to evaluate whether HRV measures could improve the differential diagnosis between Unresponsive Wakefulness Syndrome (UWS) and Minimally Conscious State (MCS) with respect to multivariate models based on standard clinical electroencephalography (EEG) labeling only in a rehabilitation setting.

METHODS

A prospective observational study was performed consecutively enrolling 82 DoC patients. Polygraphic recordings were performed. HRV-metrics and EEG descriptors derived from the American Clinical Neurophysiology Society's Standardized Critical Care terminology were included. Descriptors entered univariate and then multivariate logistic regressions with the target set to the UWS/MCS diagnosis.

RESULTS

HRV measures resulted significantly different between UWS and MCS patients, with higher values being associated with better consciousness levels. Specifically, adding HRV-related metrics to ACNS EEG descriptors increased the Nagelkerke R² from 0.350 (only EEG descriptors) to 0.565 (HRV-EEG combination) with the outcome set to the consciousness diagnosis.

CONCLUSIONS

HRV changes across the lowest states of consciousness. Rapid changes in heart rate, occurring in better consciousness levels, confirm the mutual correlation between visceral state functioning patterns and consciousness alterations.

SIGNIFICANCE

Quantitative analysis of heart rate in patients with a DoC paves the way for the implementation of low-cost pipelines supporting medical decisions within multimodal consciousness assessments.

A prediction model of clinical outcomes in prolonged disorders of consciousness: A prospective cohort study

Objective

This study aimed to establish and validate a prediction model for clinical outcomes in patients with prolonged disorders of consciousness (pDOC).

Methods

A total of 170 patients with pDOC enrolled in our rehabilitation unit were included and divided into training (n = 119) and validation sets (n = 51). Independent predictors for improved clinical outcomes were identified by univariate and multivariate logistic regression analyses, and a nomogram model was established. The nomogram performance was quantified using receiver operating curve (ROC) and calibration curves in the training and validated sets. A decision curve analysis (DCA) was performed to evaluate the clinical usefulness of this nomogram model.

Results

Univariate and multivariate logistic regression analyses indicated that age, diagnosis at entry, serum albumin (g/L), and pupillary reflex were the independent prognostic factors that were used to construct the nomogram. The area under the curve in the training and validation sets was 0.845 and 0.801, respectively. This nomogram model showed good calibration with good consistency between the actual and predicted probabilities of improved outcomes. The DCA demonstrated a higher net benefit in clinical decision-making compared to treating all or none.

Conclusion

Several feasible, cost-effective prognostic variables that are widely available in hospitals can provide an efficient and accurate prediction model for improved clinical outcomes and support clinicians to offer suitable clinical care and decision-making to patients with pDOC and their family members.

Prognosis of Chronically Ventilated Patients in a Long-Term Ventilation Facility: Association with Age, Consciousness and Cognitive State

Background: The number of adults requiring prolonged mechanical ventilation (PMV) including those with cognitive impairment or disorders of consciousness is escalating. We aimed to compare in a long-term acute care hospital (LTACH) mortality and length of stay (LOS) among three age groups (40-59y, 60-79y, ≥80y) of hospitalized PMV patients, and according to consciousness and cognitive state at admission. Methods: We obtained data from the health records of 308 adults aged ≥40 years requiring PMV hospitalized at a Chronic Ventilator Dependent Unit in a LTACH between 01/01/2015 to 06/30/2019 and followed-up until discharge or death or until 12/31/2019. Results: At admission to LTACH, 42.2% of PMV patients were in a vegetative state/ minimally conscious state (VS/MCS); 32.5% were severely cognitively impaired, 11.0% were mildly to moderately cognitively impaired, 12.3% had no cognitive impairment, and 1.9% had intellectual disability/psychiatric disorder. In-LTACH LOS (months) decreased from 34.6 ± 42.6 at age 40-59y, 19.1 ± 22.3 at 60-79y to 14.4 ± 19.3 at age ≥80y (p = .006). In-LTACH mortality was 30.6% for 40-59y, 41.1% for 60-79y and 54.8% for age ≥80y. In-LTACH LOS (months) was 23.8 ± 30.7 for VS/MCS, 15.1 ± 19.5 for the severely cognitively impaired, 10.0 ± 12.8 for mild to moderate cognitive impairment and 18.9 ± 21.9 for those without cognitive impairment (p = .02). In-LTACH mortality was 50.8% for VS/MCS, 58.0% for the severely cognitively impaired, 26.5% for mild to moderate cognitive impairment and 13.2% for those without cognitive impairment (p < .001). Conclusion: In this population requiring PMV, mortality and in-LTACH LOS worsened with age. In-LTACH LOS was longest for VS/MCS patients, who had a mean survival of about two years, followed by those without cognitive impairment and then those with severe cognitive impairment. Mortality was associated with worse consciousness and cognitive state. These findings highlight the importance of discussing end-of-life decisions with patients and family members regarding resuscitation/intubation and the long-term management of these patients.

Severe Acquired Brain Injury: Prognostic Factors of Discharge Outcome in Older Adults

Severe Acquired Brain Injury (sABI) is a leading cause of disability and requires intensive rehabilitation treatment. Discharge from the rehabilitation ward is a key moment in patient management. Delays in patient discharge can adversely affect hospital productivity and increase healthcare costs. The discharge should be structured from the hospital admission toward the most appropriate environment. The purpose of our study is to investigate early predictors of outcome for discharge in older adults with sABI. A retrospective study was performed on 22 patients who were admitted to an intensive neurorehabilitation unit between June 2019 and December 2021. Patients were divided into two outcome categories, good outcome (GO) or poor outcome (PO), based on discharge destination, and the possible prognostic factors were analyzed at one and two months after admission. Among the factors analyzed, changes in the Disability Rating Scale (DRS) and Level of Cognitive Functioning (LCF) at the first and second month of hospitalization were predictive of GO at discharge (DRS, p = 0.025; LCF, p = 0.011). The presence of percutaneous endoscopic gastrostomy at two months after admission was also significantly associated with PO (p = 0.038). High Body Mass Index (BMI) and the presence of sepsis at one month after admission were possible predictors of PO (BMI p = 0.048; sepsis p = 0.014). An analysis of dynamic predictors could be useful to guarantee an early evaluation of hospital discharge in frail patients with sABI.

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.

Predicting outcome of patients with prolonged disorders of consciousness using machine learning models based on medical complexity

Patients with severe acquired brain injury and prolonged disorders of consciousness (pDoC) are characterized by high clinical complexity and high risk to develop medical complications. The present multi-center longitudinal study aimed at investigating the impact of medical complications on the prediction of clinical outcome by means of machine learning models. Patients with pDoC were consecutively enrolled at admission in 23 intensive neurorehabilitation units (IRU) and followed-up at 6 months from onset via the Glasgow Outcome Scale-Extended (GOSE). Demographic and clinical data at study entry and medical complications developed within 3 months from admission were collected. Machine learning models were developed, targeting neurological outcomes at 6 months from brain injury using data collected at admission. Then, after concatenating predictions of such models to the medical complications collected within 3 months, a cascade model was developed. One hundred seventy six patients with pDoC (M: 123, median age 60.2 years) were included in the analysis. At admission, the best performing solution (k-Nearest Neighbors regression, KNN) resulted in a median validation error of 0.59 points [IQR 0.14] and a classification accuracy of dichotomized GOS-E of 88.6%. Coherently, at 3 months, the best model resulted in a median validation error of 0.49 points [IQR 0.11] and a classification accuracy of 92.6%. Interpreting the admission KNN showed how the negative effect of older age is strengthened when patients' communication levels are high and ameliorated when no communication is present. The model trained at 3 months showed appropriate adaptation of the admission prediction according to the severity of the developed medical complexity in the first 3 months. In this work, we developed and cross-validated an interpretable decision support tool capable of distinguishing patients which will reach sufficient independence levels at 6 months (GOS-E > 4). Furthermore, we provide an updated prediction at 3 months, keeping in consideration the rehabilitative path and the risen medical complexity.

Merging Clinical and EEG Biomarkers in an Elastic-Net Regression for Disorder of Consciousness Prognosis Prediction

Patients with Disorder of Consciousness (DoC) entering Intensive Rehabilitation Units after a severe Acquired Brain Injury have a highly variable evolution of the state of consciousness which is a complex aspect to predict. Besides clinical factors, electroencephalography has clearly shown its potential into the identification of prognostic biomarkers of consciousness recovery. In this retrospective study, with a dataset of 271 patients with DoC, we proposed three different Elastic-Net regressors trained on different datasets to predict the Coma Recovery Scale-Revised value at discharge based on data collected at admission. One dataset was completely EEG-based, one solely clinical data-based and the last was composed by the union of the two. Each model was optimized, validated and tested with a robust nested cross-validation pipeline. The best models resulted in a median absolute test error of 4.54 [IQR = 4.56], 3.39 [IQR = 4.36], 3.16 [IQR = 4.13] for respectively the EEG, clinical and hybrid model. Furthermore, the hybrid model for what concerns overcoming an unresponsive wakefulness state and exiting a DoC results in an AUC of 0.91 and 0.88 respectively. Small but useful improvements are added by the EEG dataset to the clinical model for what concerns overcoming an unresponsive wakefulness state. Data-driven techniques and namely, machine learning models are hereby shown to be capable of supporting the complex decision-making process the practitioners must face.

Clinical, Neurophysiological, and Genetic Predictors of Recovery in Patients With Severe Acquired Brain Injuries (PRABI): A Study Protocol for a Longitudinal Observational Study

Background

Due to continuous advances in intensive care technology and neurosurgical procedures, the number of survivors from severe acquired brain injuries (sABIs) has increased considerably, raising several delicate ethical issues. The heterogeneity and complex nature of the neurological damage of sABIs make the detection of predictive factors of a better outcome very challenging. Identifying the profile of those patients with better prospects of recovery will facilitate clinical and family choices and allow to personalize rehabilitation. This paper describes a multicenter prospective study protocol, to investigate outcomes and baseline predictors or biomarkers of functional recovery, on a large Italian cohort of sABI survivors undergoing postacute rehabilitation.

Methods

All patients with a diagnosis of sABI admitted to four intensive rehabilitation units (IRUs) within 4 months from the acute event, aged above 18, and providing informed consent, will be enrolled. No additional exclusion criteria will be considered. Measures will be taken at admission (T0), at three (T1) and 6 months (T2) from T0, and follow-up at 12 and 24 months from onset, including clinical and functional data, neurophysiological results, and analysis of neurogenetic biomarkers.

Statistics

Advanced machine learning algorithms will be cross validated to achieve data-driven prediction models. To assess the clinical applicability of the solutions obtained, the prediction of recovery milestones will be compared to the evaluation of a multiprofessional, interdisciplinary rehabilitation team, performed within 2 weeks from admission.

Discussion

Identifying the profiles of patients with a favorable prognosis would allow customization of rehabilitation strategies, to provide accurate information to the caregivers and, possibly, to optimize rehabilitation outcomes.

Conclusions

The application and validation of machine learning algorithms on a comprehensive pool of clinical, genetic, and neurophysiological data can pave the way toward the implementation of tools in support of the clinical prognosis for the rehabilitation pathways of patients after sABI.

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.

Behavioral signs of recovery from unresponsive wakefulness syndrome to emergence of minimally conscious state after severe brain injury

BACKGROUND

A precise description of behavioral signs denoting transition from an unresponsive wakefulness syndrome/vegetative state (UWS/VS) to minimally conscious state (MCS) or emergence from MCS after severe brain injury is crucial for prognostic purposes. A few studies have attempted this goal but involved non-standardized instruments, limited temporal accuracy or samples or focused on patients with (sub)acute condition.

OBJECTIVES

We aimed to describe the behavioral signs that led to a change in diagnosis as well as the factors affecting this transition in a large sample of patients with chronic disorders of consciousness after severe brain injury.

METHODS

In this retrospective cohort study, patients in UWS/VS or MCS were assessed with the Coma Recovery Scale Revised (CRS-R) at 5 times within the 2 weeks after their admission to a neurorehabilitation center and then weekly until emergence from MCS, discharge or death.

RESULTS

Of the 185 patients included, 33 in UWS/VS and 45 in MCS transitioned to another state. Transition to MCS was mostly denoted by one behavioral sign (71%), predominantly visual fixation, followed by localization to noxious stimulation, and visual pursuit, and could be predicted by etiology, time post-injury and age. Emergence from MCS was characterized by one sign in 64% of patients and by 2 signs (functional communication and objects use) in the remaining patients and could be predicted by time post-injury and number of behavioral signs at admission.

CONCLUSIONS

Transition from UWS to MCS was predominantly signalled by visual fixation and could be predicted by etiology, time post-injury and age. Emergence from MCS was mostly signalled by one sign and could be predicted by time post-injury and number of behavioral signs at admission. Clinicians should pay particular attention to visual and motor subscales of the CRS-R to detect behavioral recovery after severe brain injury. Database registration. ClinicalTrials.gov: NCT04687397.

The influence of the CRS-R score on functional outcome in patients with severe brain injury receiving early rehabilitation

Background

The aim of the study was to determine the role of the Coma Recovery Scale-Revised (CRS-R) in the prediction of functional status at the end of neurological early rehabilitative treatment.

Methods

Patients consecutively admitted to intensive or intermediate care units of a neurological rehabilitation center were enrolled in the study. Consciousness and functional status were assessed with the Coma Recovery Scale-Revised (CRS-R) and the Early Rehabilitation Barthel Index (ERBI), respectively. Both assessments were carried out weekly within the first month and at the end of early rehabilitation. Patient and clinical data were entered into a binary logistic regression model to predict functional status at discharge.

Results

327 patients (112 females, 215 males) with a median age of 63 years (IQR = 53–75) and a median disease duration of 18 days (IQR = 12–28) were included. Most patients suffered from stroke (59 %), followed by traumatic brain injury (31 %), and hypoxic ischemic encephalopathy (10 %). Upon admission, 12 % were diagnosed as comatose, 31 % as unresponsive wakefulness syndrome (UWS), 35 % as minimally conscious state (MCS) and 22 % already emerged from MCS (eMCS). Of all patients undergoing complete early rehabilitative treatment (n = 180), 72 % showed improvements in level of consciousness (LOC). In this group, age, initial CRS-R score and gains in CRS-R score after four weeks independently predicted functional outcome at discharge.

Conclusions

The study confirms the relevance of the CRS-R score for functional outcome prediction. High CRS-R scores and young age facilitate functional improvements and increase the probability to continue treatment in subsequent rehabilitation phases. Moreover, results indicate that recovery might occur over a period of time that extends beyond acute care.

Decannulation and improvement of responsiveness in patients with disorders of consciousness

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

Consciousness recovery after various periods in vegetative state

BACKGROUND

Recent studies suggest that late recovery from vegetative state (VS) is more prevalent today than previously thought. This study examined the decline in the rate of recovery from VS with time after admission to rehabilitation, and established a new time frame, in which the odds of recovery from VS remain substantial.

METHODS

Data of 206 patients with VS after traumatic and non-traumatic brain injuries (TBI and NTBI), who were treated at the Loewenstein Rehabilitation Hospital (LRH), in Raanana, Israel, between 2003 and 2015, and described in a previous publication, were further analysed. Rate of recovery from VS was monitored at several time points after admission to intensive care and consciousness rehabilitation (ICCR).

RESULTS

The odds of consciousness recovery were at least 54% at admission to ICCR, and 48%, 33%, 19%, and 7% at 3, 6, 9, and 12 months after admission, respectively.

CONCLUSIONS

The rate of recovery from VS decreases significantly with time, but contrary to previous consensus, 6-12 months after admission to ICCR, the odds of recovery from VS after TBI and NTBI remain substantial.

Multicenter prospective study on predictors of short-term outcome in disorders of consciousness

OBJECTIVE

This international multicenter, prospective, observational study aimed at identifying predictors of short-term clinical outcome in patients with prolonged disorders of consciousness (DoC) due to acquired severe brain injury.

METHODS

Patients in vegetative state/unresponsive wakefulness syndrome (VS/UWS) or in minimally conscious state (MCS) were enrolled within 3 months from their brain injury in 12 specialized medical institutions. Demographic, anamnestic, clinical, and neurophysiologic data were collected at study entry. Patients were then followed up for assessing the primary outcome, that is, clinical diagnosis according to standardized criteria at 6 months postinjury.

RESULTS

We enrolled 147 patients (44 women; mean age 49.4 [95% confidence interval 46.1-52.6] years; VS/UWS 71, MCS 76; traumatic 55, vascular 56, anoxic 36; mean time postinjury 59.6 [55.4-63.6] days). The 6-month follow-up was complete for 143 patients (VS/UWS 70; MCS 73). With respect to study entry, the clinical diagnosis improved in 72 patients (VS/UWS 27; MCS 45). Younger age, shorter time postinjury, higher Coma Recovery Scale-Revised total score, and presence of EEG reactivity to eye opening at study entry predicted better outcome, whereas etiology, clinical diagnosis, Disability Rating Scale score, EEG background activity, acoustic reactivity, and P300 on event-related potentials were not associated with outcome.

CONCLUSIONS

Multimodal assessment could identify patients with higher likelihood of clinical improvement in order to help clinicians, families, and funding sources with various aspects of decision-making. This multicenter, international study aims to stimulate further research that drives international consensus regarding standardization of prognostic procedures for patients with DoC.

Minimum Competency Recommendations for Programs That Provide Rehabilitation Services for Persons With Disorders of Consciousness: A Position Statement of the American Congress of Rehabilitation Medicine and the National Institute on Disability, Independent Living and Rehabilitation Research Traumatic Brain Injury Model Systems

Persons who have disorders of consciousness (DoC) require care from multidisciplinary teams with specialized training and expertise in management of the complex needs of this clinical population. The recent promulgation of practice guidelines for patients with prolonged DoC by the American Academy of Neurology, American Congress of Rehabilitation Medicine (ACRM), and National Institute on Disability, Independent Living, and Rehabilitation Research (NIDILRR) represents a major advance in the development of care standards in this area of brain injury rehabilitation. Implementation of these practice guidelines requires explication of the minimum competencies of clinical programs providing services to persons who have DoC. The Brain Injury Interdisciplinary Special Interest Group of the ACRM, in collaboration with the Disorders of Consciousness Special Interest Group of the NIDILRR-Traumatic Brain Injury Model Systems convened a multidisciplinary panel of experts to address this need through the present position statement. Content area-specific workgroups reviewed relevant peer-reviewed literature and drafted recommendations which were then evaluated by the expert panel using a modified Delphi voting process. The process yielded 21 recommendations on the structure and process of essential services required for effective DoC-focused rehabilitation, organized into 4 categories: diagnostic and prognostic assessment (4 recommendations), treatment (11 recommendations), transitioning care/long-term care needs (5 recommendations), and management of ethical issues (1 recommendation). With few exceptions, these recommendations focus on infrastructure requirements and operating procedures for the provision of DoC-focused neurorehabilitation services across subacute and postacute settings.

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.

Prediction of functional outcome and discharge destination in patients with traumatic brain injury after post-acute rehabilitation

As the survival rate of traumatic brain injury increases, the burden of care for patients with traumatic brain injury is emerging as a socioeconomic issue and the discharge destination is one of the important outcome measures in the post-acute rehabilitation unit. To investigate the predictors of functional outcome and discharge destination in patients with traumatic brain injury after post-acute rehabilitation. A retrospective review was performed on 86 patients who were admitted to the rehabilitation unit between January 2010 and June 2017. Multiple regression analysis was used as a statistical method to identify the factors affecting Modified Barthel Index and discharge destination. The number of days from traumatic brain injury onset to rehabilitation unit admission (odds ratio = 0.959, P = 0.049), brain surgery for traumatic brain injury management (odds ratio = 0.160, P = 0.021), initial Glasgow Coma Scale score (odds ratio = 1.269, P = 0.022) and Mini-Mental State Examination score at admission (odds ratio = 1.245, P < 0.001) were the predictive factors for higher Modified Barthel Index after rehabilitation. Underlying vascular risk factors (odds ratio = 0.138, P = 0.015), Modified Barthel Index score after rehabilitation (odds ratio = 1.085, P < 0.001) and deductible-free insurance (odds ratio = 0.211, P = 0.032) were the predictive factors of home discharge. The functional outcome of patients with traumatic brain injury after rehabilitation was related to the severity of initial injury, cognitive function at admission and rehabilitation timing. The discharge destination after rehabilitation was related to functional outcome, insurance issues and underlying vascular risk factors.

Longitudinal assessments highlight long-term behavioural recovery in disorders of consciousness

Accurate diagnosis and prognosis of disorders of consciousness is complicated by the variability amongst patients' trajectories. However, the majority of research and scientific knowledge in this field is based on cross-sectional studies. The translational gap in applying this knowledge to inform clinical management can only be bridged by research that systematically examines follow-up. In this study, we present findings from a novel longitudinal study of the long-term recovery trajectory of 39 patients, repeatedly assessed using the Coma Recovery Scale-Revised once every 3 months for 2 years, generating 185 assessments. Despite the expected inter-patient variability, there was a statistically significant improvement in behaviour over time. Further, improvements began approximately 22 months after injury. Individual variation in the trajectory of recovery was influenced by initial diagnosis. Patients with an initial diagnosis of unresponsive wakefulness state, who progressed to the minimally conscious state, did so at a median of 485 days following onset-later than 12-month period after which current guidelines propose permanence. Although current guidelines are based on the expectation that patients with traumatic brain injury show potential for recovery over longer periods than those with non-traumatic injury, we did not observe any differences between trajectories in these two subgroups. However, age was a significant predictor, with younger patients showing more promising recovery. Also, progressive increases in arousal contributed exponentially to improvements in behavioural awareness, especially in minimally conscious patients. These findings highlight the importance of indexing arousal when measuring awareness, and the potential for interventions to regulate arousal to aid long-term behavioural recovery in disorders of consciousness.

Outcome prediction in disorders of consciousness: the role of coma recovery scale revised

Background

To evaluate the utility of the revised coma remission scale (CRS-r), together with other clinical variables, in predicting emergence from disorders of consciousness (DoC) during intensive rehabilitation care.

Methods

Data were retrospectively extracted from the medical records of patients enrolled in a specialized intensive rehabilitation unit. 123 patients in a vegetative state (VS) and 57 in a minimally conscious state (MCS) were included and followed for a period of 8 weeks. Demographical and clinical factors were used as outcome measures. Univariate and multivariate Cox regression models were employed for examining potential predictors for clinical outcome along the time.

Results

VS and MCS groups were matched for demographical and clinical variables (i.e., age, aetiology, tracheostomy and route of feeding). Within 2 months after admission in intensive neurorehabilitation unit, 3.9% were dead, 35.5% had a full recovery of consciousness and 66.7% remained in VS or MCS. Multivariate analysis demonstrated that the best predictor of functional improvement was the CRS-r scores. In particular, patients with values greater than 12 at admission were those with a favourable likelihood of emergence from DoC.

Conclusions

Our study highlights the role of the CRS-r scores for predicting a short-term favorable outcome.

Clinical Features of Disorders of Consciousness in Young Children

OBJECTIVES

To investigate behavioral and demographic features of levels of consciousness in young children with brain injury, including the classifications of consciousness: conscious state (CS), minimally conscious state (MCS), and vegetative state (VS), and to investigate the course of recovery in children with disorders of consciousness (DOC).

DESIGN

Retrospective chart review and post hoc analysis.

SETTING

Pediatric inpatient rehabilitation unit.

PARTICIPANTS

Children aged 6 months to 5 years (N=54) admitted for inpatient rehabilitation directly from an acute care hospital following new neurologic injury from 2011 to 2016.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Clinically abstracted behavioral features of DOC and levels of consciousness at admission and discharge, based on established guidelines from the Aspen Neurobehavioral Conference Workgroup.

RESULTS

Children in MCS were younger than children in CS. Commonly observed behaviors in children in VS were mouth movements or vocalizations, flexion withdrawal or motor posturing, visual or auditory startle, and localization to sound. Common features of MCS were contingent affect, visual fixation or pursuit, automatic motor behavior, and contingent communicative intent. No children in MCS showed command following or intelligible verbalizations. All children in CS showed functional object use, while functional communication was observed in a subset. By discharge, more than half of children in VS emerged to MCS, and a third emerged from MCS to CS. No child emerged from VS to CS.

CONCLUSIONS

Visual and motor skills may be most applicable, and language-based skills may be least applicable for the assessment of DOC in very young children. Accurate classifications of consciousness may have important prognostic implications, and additional research is needed to develop clear guidelines for assessment of DOC in this population.

Treating Disorders of Consciousness With Apomorphine: Protocol for a Double-Blind Randomized Controlled Trial Using Multimodal Assessments

Background: There are few available therapeutic options to promote recovery among patients with chronic disorders of consciousness (DOC). Among pharmacological treatments, apomorphine, a dopamine agonist, has exhibited promising behavioral effects and safety of use in small-sample pilot studies. The true efficacy of the drug and its neural mechanism are still unclear. Apomorphine may act through a modulation of the anterior forebrain mesocircuit, but neuroimaging and neurophysiological investigations to test this hypothesis are scarce. This clinical trial aims to (1) assess the treatment effect of subcutaneous apomorphine infusions in patients with DOC, (2) better identify the phenotype of responders to treatment, (3) evaluate tolerance and side effects in this population, and (4) examine the neural networks underlying its modulating action on consciousness. Methods/Design: This study is a prospective double-blind randomized parallel placebo-controlled trial. Forty-eight patients diagnosed with DOC will be randomized to receive a 30-day regimen of either apomorphine hydrochloride or placebo subcutaneous infusions. Patients will be monitored at baseline 30 days before initiation of therapy, during treatment and for 30 days after treatment washout, using standardized behavioral scales (Coma Recovery Scale-Revised, Nociception Coma Scale-Revised), neurophysiological measures (electroencephalography, body temperature, actigraphy) and brain imaging (magnetic resonance imaging, positron emission tomography). Behavioral follow-up will be performed up to 2 years using structured phone interviews. Analyses will look for changes in behavioral status, circadian rhythmicity, brain metabolism, and functional connectivity at the individual level (comparing before and after treatment) and at the group level (comparing apomorphine and placebo arms, and comparing responder and non-responder groups). Discussion: This study investigates the use of apomorphine for the recovery of consciousness in the first randomized placebo-controlled double-blind trial using multimodal assessments. The results will contribute to define the role of dopamine agonists for the treatment of these challenging conditions and identify the neural correlates to their action. Results will bring objective evidence to further assess the modulation of the anterior forebrain mesocircuit by pharmacological agents, which may open new therapeutic perspectives. Clinical Trial Registration: EudraCT n°2018-003144-23; Clinicaltrials.gov n°NCT03623828 (https://clinicaltrials.gov/ct2/show/NCT03623828).

Recovery from vegetative state of patients with a severe brain injury: a 4-year real-practice prospective cohort study

Patients who have suffered severe traumatic or nontraumatic brain injuries can show a progressive recovery, transitioning through a range of clinical conditions. They may progress from coma to a vegetative state (VS) and/or a minimally conscious state (MCS). A longer duration of the VS is known to be related to a lower probability of emergence from it; furthermore, the literature seems to lack evidence of late improvements in these patients. This real-practice prospective cohort study was conducted in inpatients in a VS following a severe brain injury, consecutively admitted to a vegetative state unit (VSU). The aim of the study was to assess their recovery in order to identify variables that might increase the probability of a VS patient transitioning to MCS. Rehabilitation treatment included passive joint mobilisation and helping/placing patients into an upright sitting position on a tilt table. All the patients underwent a specific assessment protocol every month to identify any emergence, however late, from the VS. Over a 4-year period, 194 patients suffering sequelae of a severe brain injury, consecutively seen, had an initial Glasgow Coma Scale score ≤ 8. Of these, 63 (32.5%) were in a VS, 84 (43.3%) in a MCS, and 47 (24.2%) in a coma; of the 63 patients admitted in a VS, 49 (57.1% males and 42.9% females, mean age 25.34 ± 19.12 years) were transferred to a specialist VSU and put on a slow-to-recover brain injury programme. Ten of these 49 patients were still in a VS after 36 months; of these 10, 3 recovered consciousness, transitioning to a MCS, 2 died, and 5 remained in a VS during the last 12 months of the observation. Univariate analysis identified male sex, youth, a shorter time from onset of the VS, diffuse brain injury, and the presence of status epilepticus as variables increasing the likelihood of transition to a MCS. Long-term monitoring of patients with chronic disorders of consciousness should be adequately implemented in order to optimise their access to rehabilitation services.

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.

Association between Outcome of Severe Traumatic Brain Injury and Demographic, Clinical, Injury-related Variables of Patients

Background:

Traumatic brain injury (TBI) is a main health problem among communities. There exists a variety of effective factors on the outcome of patients with TBI. We describe the demographic, clinical, and injury related variables of the patients with severe TBI, and determine the predictors of outcome.

Materials and Methods:

We did this cross-sectional study on all 267 adult patients with severe TBI admitted to three trauma centers of Isfahan University of Medical Sciences (IUMS) from March 20, 2014 to March 19, 2015. Data were extracted from patients' profiles. We considered the patients' outcome as discharged and died. We analyzed the collected data using descriptive (frequency, mean, and standard deviation) and analytical (independent t-test, Mann–Whitney U-test, Kruskal–Wallis test and logistic regression) statistics in Statistical Package for the Social Sciences (SPSS) 16.0. We considered p < 0.05 as the significance level.

Results:

The mean (SD) age of patients was 43.86 (18.40) years. The majority of the population was men (87.27%). Road traffic accidents (RTAs) were the most common mechanism of trauma (79.40%). The mean (SD) of Glasgow coma scale (GCS) was 6.03 (3.11). In 50.19% of the patients, the pupillary reflex was absent. One hundred and twenty-four patients (46.44%) died before discharge. We found age, gender, GCS, pupillary reflex, hypernatremia, and increased intracranial pressure (IICP) as the predictors of death in severe TBI.

Conclusions:

In this study, the mortality rate of patients with severe TBI was high. In addition, some factors were determined as the significant predictors of outcome. The findings can assist in planning to enhance the quality of care and reduce the mortality rate in the patients with severe TBI.

Alterations in the brain's connectome during recovery from severe traumatic brain injury: protocol for a longitudinal prospective study

INTRODUCTION

Traumatic brain injury (TBI) is considered one of the most pervasive causes of disability in people under the age of 45. TBI often results in disorders of consciousness, and clinical assessment of the state of consciousness in these patients is challenging due to the lack of behavioural responsiveness. Functional neuroimaging offers a means to assess these patients without the need for behavioural signs, indicating that brain connectivity plays a major role in consciousness emergence and maintenance. However, little is known regarding how changes in connectivity during recovery from TBI accompany changes in the level of consciousness. Here, we aim to combine cutting-edge neuroimaging techniques to follow changes in brain connectivity in patients recovering from severe TBI.

METHODS AND ANALYSIS

A multimodal, longitudinal assessment of 30 patients in the subacute stage after severe TBI will be made comprising an MRI session combined with electroencephalography (EEG), a positron emission tomography session and a transcranial magnetic stimulation (TMS) combined with EEG (TMS/EEG) session. A group of 20 healthy participants will be included for comparison. Four sessions for patients and two sessions for healthy participants will be planned. Data analysis techniques will focus on whole-brain, both data-driven and hypothesis-driven, connectivity measures that will be specific to the imaging modality.

ETHICS AND DISSEMINATION

The project has received ethical approval by the local ethics committee of the Capital Region of Denmark and by the Danish Data Protection. Results will be published as original research articles in peer-reviewed journals and disseminated in international conferences. None of the measurements will have any direct clinical impact on the patients included in the study but may benefit future patients through a better understanding of the mechanisms underlying the recovery process after TBI. TRIAL REGISTRATION NUMBER NCT02424656; PRE-RESULTS.

Ten-to-twelve years after specialized neurorehabilitation of young patients with severe disorders of consciousness: A follow-up study

OBJECTIVE

To explore the long-term outcome of young patients with disorders of consciousness who had received intensive neurorehabilitation.

METHODS

A cross-sectional cohort study, in which the survival, level of consciousness, functional independence, mobility, communication and living situation were determined by means of a structured questionnaire. The cohort consisted of 44 children and young adults, originally either in a prolonged Vegetative State/Unresponsive Wakefulness Syndrome (VS/UWS, n = 33) or a Minimally Conscious State (MCS, n = 11) who had received a specialized neurorehabilitation programme 10-12 years earlier.

RESULTS

Response rate was 72% (34/44). Eleven patients were deceased, 10 of whom were in VS/UWS or MCS at discharge from the programme. Of the remaining 23 patients, 19 were conscious. Twelve lived independently, of whom six required some household support. One conscious patient lived permanently in a long-term care facility. All other patients lived either independently or with their parents. None of the VS/UWS or MCS patients showed any functional recovery.

CONCLUSION

Two main long-term outcome scenarios can be recognized. Two-thirds of the participating patients who were conscious at programme discharge were able to live independently, whereas almost two-thirds of the participating patients who were in VS/UWS or MCS at discharge subsequently died.

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.

Results of a prospective study (CATS) on the effects of thalamic stimulation in minimally conscious and vegetative state patients

OBJECTIVE Deep brain stimulation of the thalamus was introduced more than 40 years ago with the objective of improving the performance and attention of patients in a vegetative or minimally conscious state. Here, the authors report the results of the Cortical Activation by Thalamic Stimulation (CATS) study, a prospective multiinstitutional study on the effects of bilateral chronic stimulation of the anterior intralaminar thalamic nuclei and adjacent paralaminar regions in patients affected by a disorder of consciousness. METHODS The authors evaluated the clinical and radiological data of 29 patients in a vegetative state (unresponsive wakefulness syndrome) and 11 in a minimally conscious state that lasted for more than 6 months. Of these patients, 5 were selected for bilateral stereotactic implantation of deep brain stimulating electrodes into their thalamus. A definitive consensus for surgery was obtained for 3 of the selected patients. All 3 patients (2 in a vegetative state and 1 in a minimally conscious state) underwent implantation of bilateral thalamic electrodes and submitted to chronic stimulation for a minimum of 18 months and a maximum of 48 months. RESULTS In each case, there was an increase in desynchronization and the power spectrum of electroencephalograms, and improvement in the Coma Recovery Scale-Revised scores was found. Furthermore, the severity of limb spasticity and the number and severity of pathological movements were reduced. However, none of these patients returned to a fully conscious state. CONCLUSIONS Despite the limited number of patients studied, the authors confirmed that bilateral thalamic stimulation can improve the clinical status of patients affected by a disorder of consciousness, even though this stimulation did not induce persistent, clinically evident conscious behavior in the patients. Clinical trial registration no.: NCT01027572 ( ClinicalTrials.gov ).

A note on survival after anoxic brain injury in adolescents and young adults

BACKGROUND

Much is known about survival after traumatic brain injury (TBI), yet relatively little about survival after anoxic brain injury (ABI).

OBJECTIVE

To determine whether long-term survival after ABI is comparable to that after TBI.

METHODS

We identified 237 patients with ABI and 1,620 with TBI in California who were aged 15 to 35, survived at least 1 year post injury, and were injured in 1986 or later. We analyzed the long-term follow-up data using the Cox Proportional Hazards Regression Model, controlling for age, sex, and severity of disability.

RESULTS

After adjustment for risk factors, no significant differences in long-term survival between ABI and TBI were found (hazard ratio = 0.97; 95% c.i. 0.57-1.65).

CONCLUSIONS

In adolescents and young adults, long-term survival after ABI appears to be similar to that after TBI.

Traumatic Brain Injury Patient, Injury, Therapy, and Ancillary Treatments Associated With Outcomes at Discharge and 9 Months Postdischarge

OBJECTIVE

To examine associations of patient and injury characteristics, inpatient rehabilitation therapy activities, and neurotropic medications with outcomes at discharge and 9 months postdischarge for patients with traumatic brain injury (TBI).

DESIGN

Prospective, longitudinal observational study.

SETTING

Inpatient rehabilitation centers.

PARTICIPANTS

Consecutive patients (N=2130) enrolled between 2008 and 2011, admitted for inpatient rehabilitation after an index TBI injury.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Rehabilitation length of stay, discharge to home, and FIM at discharge and 9 months postdischarge.

RESULTS

The admission FIM cognitive score was used to create 5 relatively homogeneous subgroups for subsequent analysis of treatment outcomes. Within each subgroup, significant associations were found between outcomes and patient and injury characteristics, time spent in therapy activities, and medications used. Patient and injury characteristics explained on average 35.7% of the variation in discharge outcomes and 22.3% in 9-month outcomes. Adding time spent and level of effort in therapy activities and percentage of stay using specific medications explained approximately 20% more variation for discharge outcomes and 12.9% for 9-month outcomes. After patient, injury, and treatment characteristics were used to predict outcomes, center differences added only approximately 1.9% additional variance explained.

CONCLUSIONS

At discharge, greater effort during therapy sessions, time spent in more complex therapy activities, and use of specific medications were associated with better outcomes for patients in all admission FIM cognitive subgroups. At 9 months postdischarge, similar but less pervasive associations were observed for therapy activities, but not classes of medications. Further research is warranted to examine more specific combinations of therapy activities and medications that are associated with better outcomes.

Gait and Glasgow Coma Scale scores can predict functional recovery in patients with traumatic brain injury

Fifty-one patients with mild (n = 14), moderate (n = 10) and severe traumatic brain injury (n = 27) received early rehabilitation. Level of consciousness was evaluated using the Glasgow Coma Score. Functional level was determined using the Glasgow Outcome Score, whilst mobility was evaluated using the Mobility Scale for Acute Stroke. Activities of daily living were assessed using the Barthel Index. Following Bobath neurodevelopmental therapy, the level of consciousness was significantly improved in patients with moderate and severe traumatic brain injury, but was not greatly influenced in patients with mild traumatic brain injury. Mobility and functional level were significantly improved in patients with mild, moderate and severe traumatic brain injury. Gait recovery was more obvious in patients with mild traumatic brain injury than in patients with moderate and severe traumatic brain injury. Activities of daily living showed an improvement but this was insignificant except for patients with severe traumatic brain injury. Nevertheless, complete recovery was not acquired at discharge. Multiple regression analysis showed that gait and Glasgow Coma Scale scores can be considered predictors of functional outcomes following traumatic brain injury.

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.

Examining acute rehabilitation outcomes for children with total functional dependence after traumatic brain injury: a pilot study

OBJECTIVE

To examine in a pilot cohort factors associated with functional outcome at discharge and 3-month follow-up after discharge from inpatient rehabilitation in children with severe traumatic brain injury (TBI) who entered rehabilitation with the lowest level of functional skills.

PARTICIPANTS

Thirty-nine children and adolescents (3-18 years old) who sustained a severe TBI and had the lowest possible rating at rehabilitation admission on the Functional Independence Measure for Children (total score = 18).

METHODS

Retrospective review of data collected as part of routine clinical care.

RESULTS

At discharge, 59% of the children were partially dependent for basic activities, while 41% remained dependent for basic activities. Initial Glasgow Coma Scale score, time to follow commands, and time from injury to rehabilitation admission were correlated with functional status at discharge. Time to follow commands and time from injury to rehabilitation admission were correlated with functional status at 3-month follow-up. Changes in functional status during the first few weeks of admission were associated with functional status at discharge and follow-up.

CONCLUSIONS

Even children with the most severe brain injuries, who enter rehabilitation completely dependent for all daily activities, have the potential to make significant gains in functioning by discharge and in the following few months. Assessment of functional status early in the course of rehabilitation contributes to the ability to predict outcome from severe TBI.

Assessing learning as a possible sign of consciousness in post-coma persons with minimal responsiveness

A learning test procedure based on operant principles may be useful in the diagnosis (and eventually rehabilitation) of post-coma persons with minimal responsiveness. This study was aimed at extending the evaluation of such a procedure with seven participants who presented with very limited behavior and apparently severe disorders of consciousness. The procedure was evaluated through an ABACB design, in which A represented baseline phases without stimulation, B intervention phases with brief stimulation periods contingent on specific responses of the participants, and C a control phase in which stimulation was available all the time. Increased responding during the B phases, as opposed to the A and C phases, was taken to indicate learning and possibly a non-reflective expression of phenomenal consciousness. All participants were also evaluated with the coma recovery scale-revised (CRS-R) prior to the start of the learning test procedure and at the end of it. The results of the learning test showed that all participants had significantly higher responding levels during the B phases. The CRS-R scores suggested minimally conscious state for four of them prior to the learning test and for five of them after the completion of the learning test. The implications of the findings are discussed in terms of potential and time cost of the learning test.

Predicting early awakening from coma after intracerebral hemorrhage

INTRODUCTION

Given the high morbidity and mortality associated with intracerebral hemorrhage (ICH), family members, and healthcare providers base early supportive management decisions, at least in part, on expected prognosis. In the comatose patient with ICH, this short-term prognosis is most overtly characterized by regaining of consciousness.

DESIGN

A retrospective consecutive cohort of 51 patients admitted to a neuroICU with ICH and admission Glasgow Coma Scale score ≤8 was identified. Logistic regression was performed to assess the association of baseline characteristics and treatment parameters associated with awakening.

RESULTS

Awakening from coma was observed in 53% of ICH patients: 83% with an initial GCS score of 7-8, 43% with an initial score of 5-6, and 20% with an initial score of 3-4. Awakening from coma in the cohort of 27 patients who regained consciousness occurred in 59% of patients by day 2, 89% by day 7, and 96% by day 9. In multivariable analysis, only higher admission GCS score was associated with a greater likelihood of awakening from coma [OR 4.9 (95% CI 1.9-13) per two-point category, p = 0.001]. DNR status during the first 24 h was not associated with awakening but was at later time points.

CONCLUSION

GCS score is the predominant initial predictor of early awakening in patients who present in coma after ICH. Patients who regained consciousness typically did so within the first 9 days of hospital admission.

Our rapidly changing understanding of acute and chronic disorders of consciousness: challenges for neurologists

A number of recent studies suggest that some ‘vegetative state’ patients have been misdiagnosed, judging by their ability to follow commands and in some cases even communicate through brain activity. Such studies highlight the difficulty in forming a diagnosis based only on behavioral assessments. We think that neuroimaging and electrophysiology methods will be used more frequently in clinical settings, integrated with existing behavioral assessments. Such efforts are expected to lead to a more accurate understanding of individual patients’ cognitive abilities or even provide prognostic indicators. In terms of treatment planning (i.e., pain management and end-of-life decision-making), patients with disorders of consciousness are now offered the possibility of expressing their preferences by means of brain–computer interfaces. What remains to be clarified is the degree to which such indirect responses can be considered reliable and of legal representation.

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.