The reliability and validity of the PALOC-s: a post-acute level of consciousness scale for assessment of young patients with prolonged disturbed consciousness after brain injury

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

BACKGROUND

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

AIM

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

DESIGN

Retrospective observational multisite study.

SETTING

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

POPULATION

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

CLINICAL REHABILITATION IMPACT

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

Disorders of Consciousness in Children: Assessment, Treatment, and Prognosis

Children with acquired brain injury may experience prolonged disorders of consciousness (DoC); research on children with DoC lags behind adult literature. Rigorous evaluation of assessment tools used in children with DoC is lacking, though recent developments may contribute to improvements in care, particularly for assessment of young children and those without overt command following. Literature on prognosis continues to grow, reinforcing that early signs of consciousness suggest better long-term outcome. Although large clinical trials for children with DoC are lacking, single-site and multisite programmatic data inform standards of care and treatment options for children with DoC.

Pediatric disorders of consciousness: Considerations, controversies, and caveats

Pediatric disorders of consciousness (PedDOC) encompass conditions that may occur following very severe traumatic or other forms of acquired brain injury sustained during childhood. As in adults, PedDOC is described as a disturbance of awareness and/or responsiveness. PedDOC is a complex condition that requires specialized care, infrastructures, and technologies. PedDOC poses many challenges to healthcare providers and caregivers during recovery and throughout development. In this commentary, we intend to highlight some considerations, controversies, and caveats on the diagnosis, prognosis and treatment of PedDOC.

Post-Acute Level Of Consciousness scale revised (PALOC-sr): adaptation of a scale for classifying the level of consciousness in patients with a prolonged disorder of consciousness

OBJECTIVE

To present an updated version of the 'Post-acute Level Of Consciousness scale' (PALOC-s), in accordance with the latest scientific insights.

METHODS

Within the context of a research project, 20 years ago, the PALOC-s was developed for the purpose of following the development of the level of consciousness of young unconscious patients participating in a rehabilitation program. Meanwhile, the understanding of the behavior related to different levels of consciousness has developed and terminology has changed, resulting in the need to revise the PALOC-s. With the preservation of the original description of the eight hierarchical levels of PALOC-s, adaptations are made in the terminology and grouping of these levels.

RESULTS AND CONCLUSION

This manuscript presents the revised version of PALOC-sr, which is suitable for use in clinical practice. The validation of this scale is recommended for its optimal use in future (international) research projects.

Development of expert consensus to guide physical rehabilitation in children and adolescents with acquired brain injury during the subacute phase

OBJECTIVE

To develop consensus among experts to guide physical rehabilitation in children and adolescents with acquired brain injury during the subacute phase.

DESIGN

International Delphi study.

METHODS

A 3-round online Delphi study was conducted with 11 international experts in rehabilitation for children and adolescents with acquired brain injury. The first round consisted of open-ended questions; the second and third round consisted of ranking 139 statements on a 5-point Likert scale.

RESULTS

The panel reached consensus on 116/139 statements. Consensus was reached on the importance of age, pre-injury developmental stage and the clinical presentation of the child when determining content and focus of physical rehabilitation. In addition, consensus was reached on the importance of participation-focused interventions, and involvement of family members in goal-setting and therapeutic activities. Although dosage was deemed very important, no consensus was reached for determination of dose-response variables to suit and influence the child's needs.

CONCLUSION

This study provides a framework for clinicians to design physical rehabilitation interventions in children with acquired brain injury in the sub-acute recovery phase. The promotion of physical activity in meaningful contexts and involvement of family members are considered as important components to optimize recovery.

Scoping Review on the Diagnosis, Prognosis, and Treatment of Pediatric Disorders of Consciousness

BACKGROUND AND OBJECTIVES

Comprehensive guidelines for the diagnosis, prognosis, and treatment of disorders of consciousness (DoC) in pediatric patients have not yet been released. We aimed to summarize available evidence for DoC with >14 days duration to support the future development of guidelines for children, adolescents and young adults aged 6 months-18 years.

METHODS

This scoping review was reported based on Preferred Reporting Items for Systematic reviews and Meta-Analyses-extension for Scoping Reviews guidelines. A systematic search identified records from 4 databases: PubMed, Embase, Cochrane Library, and Web of Science. Abstracts received 3 blind reviews. Corresponding full-text articles rated as "in-scope" and reporting data not published in any other retained article (i.e., no double reporting) were identified and assigned to 5 thematic evaluating teams. Full-text articles were reviewed using a double-blind standardized form. Level of evidence was graded, and summative statements were generated.

RESULTS

On November 9, 2022, 2,167 documents had been identified; 132 articles were retained, of which 33 (25%) were published over the past 5 years. Overall, 2,161 individuals met the inclusion criteria; female patients were 527 of 1,554 (33.9%) cases included, whose sex was identifiable. Of 132 articles, 57 (43.2%) were single case reports and only 5 (3.8%) clinical trials; the level of evidence was prevalently low (80/132; 60.6%). Most studies included neurobehavioral measures (84/127; 66.1%) and neuroimaging (81/127; 63.8%); 59 (46.5%) were mainly related to diagnosis, 56 (44.1%) to prognosis, and 44 (34.6%) to treatment. Most frequently used neurobehavioral tools included the Coma Recovery Scale-Revised, Coma/Near-Coma Scale, Level of Cognitive Functioning Assessment Scale, and Post-Acute Level of Consciousness scale. EEG, event-related potentials, structural CT, and MRI were the most frequently used instrumental techniques. In 29/53 (54.7%) cases, DoC improvement was observed, which was associated with treatment with amantadine.

DISCUSSION

The literature on pediatric DoCs is mainly observational, and clinical details are either inconsistently presented or absent. Conclusions drawn from many studies convey insubstantial evidence and have limited validity and low potential for translation in clinical practice. Despite these limitations, our work summarizes the extant literature and constitutes a base for future guidelines related to the diagnosis, prognosis, and treatment of pediatric DoC.

Measurement Feedback System for Intensive Neurorehabilitation after Severe Acquired Brain Injury

Outcome of acquired brain injury (ABI) and the potential for neurorehabilitation are subject to distinct heterogeneity between patients. Limited knowledge of the complex constellation of determinants at play interferes with the possibility to deploy precision medicine in neurorehabilitation. Measurement Feedback Systems (MFS) structure clinical data collection and deliver the measurement results as feedback to clinicians, thereby facilitating progress monitoring, promoting balanced patient-centered discussion and shared decision making. Accumulation of clinical data in the MFS also enables data-driven precision rehabilitation medicine. This article describes the development and implementation of a MFS for neurorehabilitation after ABI. The MFS consists of specialized measurement tracks which are developed together with representatives of each discipline in the multidisciplinary team. The MFS is built into a digital platform that automatically distributes measurements among clinicians, at predetermined time points during the inpatient treatment, outpatient treatment and follow-up. The results of all measurements are visualized in individual patient dashboards that are accessible for all clinicians involved in treatment. Since step-wise implementation, 124 patients have been registered on the MFS platform so far, providing an average of more than 200 new measurements per week. Currently, more than 15,000 clinical measurements are captured in the MFS. The current overall completion rate of measurements is 86,4%. This study shows that structured clinical assessment and feedback is feasible in the context of neurorehabilitation after severe ABI. The future directions are discussed for MFS data in our Health Intelligence Program, which aims at periodic care evaluation and the transition of neurorehabilitation care towards precision medicine.

Emerging Treatments for Disorders of Consciousness in Paediatric Age

The number of paediatric patients living with a prolonged Disorder of Consciousness (DoC) is growing in high-income countries, thanks to substantial improvement in intensive care. Life expectancy is extending due to the clinical and nursing management achievements of chronic phase needs, including infections. However, long-known pharmacological therapies such as amantadine and zolpidem, as well as novel instrumental approaches using direct current stimulation and, more recently, stem cell transplantation, are applied in the absence of large paediatric clinical trials and rigorous age-balanced and dose-escalated validations. With evidence building up mainly through case reports and observational studies, there is a need for well-designed paediatric clinical trials and specific research on 0-4-year-old children. At such an early age, assessing residual and recovered abilities is most challenging due to the early developmental stage, incompletely learnt motor and cognitive skills, and unreliable communication; treatment options are also less explored in early age. In middle-income countries, the lack of rehabilitation services and professionals focusing on paediatric age hampers the overall good assistance provision. Young and fast-evolving health insurance systems prevent universal access to chronic care in some countries. In low-income countries, rescue networks are often inadequate, and there is a lack of specialised and intensive care, difficulty in providing specific pharmaceuticals, and lower compliance to intensive care hygiene standards. Despite this, paediatric cases with DoC are reported, albeit in fewer numbers than in countries with better-resourced healthcare systems. For patients with a poor prospect of recovery, withdrawal of care is inhomogeneous across countries and still heavily conditioned by treatment costs as well as ethical and cultural factors, rather than reliant on protocols for assessment and standardised treatments. In summary, there is a strong call for multicentric, international, and global health initiatives on DoC to devote resources to the paediatric age, as there is now scope for funders to invest in themes specific to DoC affecting the early years of the life course.

Brain Data in Pediatric Disorders of Consciousness: Special Considerations

SUMMARY

The diagnosis and management of disorders of consciousness in children continue to present a clinical, research, and ethical challenge. Though the practice guidelines for diagnosis and management of disorders of consciousness in adults are supported by decades of empirical and pragmatic evidence, similar guidelines for infants and children are lacking. The maturing conscious experience and the limited behavioral repertoire to report consciousness in this age group restrict extrapolation from the adult literature. Equally challenging is the process of heightened structural and functional neuroplasticity in the developing brain, which adds a layer of complexity to the investigation of the neural correlates of consciousness in infants and children. This review discusses the clinical assessment of pediatric disorders of consciousness and delineates the diagnostic and prognostic utility of neurophysiological and neuroimaging correlates of consciousness. The potential relevance of these correlates for the developing brain based on existing theoretical models of consciousness in adults is outlined.

Interventions to improve outcomes in children and young people with unresponsive wakefulness syndrome following acquired brain injury: A systematic review

Unresponsive wakefulness syndrome (UWS) is a disorder of consciousness (DoC) which describes a state of wakefulness without evidence of self or environmental awareness, or interaction. There is currently no universally accepted evidence-based intervention for the treatment of UWS. This systematic review aimed to identify interventions to improve functioning in children and young people (0-25 years) with UWS following acquired brain injury (ABI). A systematic review of electronic databases was conducted, consisting of CINAHL, EMBASE, Medline, PsycINFO, PubMed, Cochrane Library, Scopus and Google Scholar. Eight studies met inclusion criteria. In these studies, the outcomes of interventions which aimed to improve quality of life, functional outcomes and/or increases in level of consciousness of paediatric patients in UWS were reported. Retrieved studies presented some evidence for improved consciousness and functional outcomes, following multi-component neurorehabilitation programmes, sensory stimulation or pharmacological interventions. Quality appraisal, using a modified version of the Downs and Black (1998) checklist, revealed risk of bias in a number of sources, including insufficient control over confounding variables, the use of inadequately validated outcome measures and concerns regarding diagnostic accuracy. More robust research is needed to adequately determine which interventions are most valuable at improving outcomes in paediatric UWS and to provide an improved evidence base for clinicians to draw upon when selecting treatment for patients.

Task-free spectral EEG dynamics track and predict patient recovery from severe acquired brain injury

For some patients, coma is followed by a state of unresponsiveness, while other patients develop signs of awareness. In practice, detecting signs of awareness may be hindered by possible impairments in the patient's motoric, sensory, or cognitive abilities, resulting in a substantial proportion of misdiagnosed disorders of consciousness. Task-free paradigms that are independent of the patient's sensorimotor and neurocognitive abilities may offer a solution to this challenge. A limitation of previous research is that the large majority of studies on the pathophysiological processes underlying disorders of consciousness have been conducted using cross-sectional designs. Here, we present a study in which we acquired a total of 74 longitudinal task-free EEG measurements from 16 patients (aged 6–22 years, 12 male) suffering from severe acquired brain injury, and an additional 16 age- and education-matched control participants. We examined changes in amplitude and connectivity metrics of oscillatory brain activity within patients across their recovery. Moreover, we applied multi-class linear discriminant analysis to assess the potential diagnostic and prognostic utility of amplitude and connectivity metrics at the individual-patient level. We found that over the course of their recovery, patients exhibited nonlinear frequency band-specific changes in spectral amplitude and connectivity metrics, changes that aligned well with the metrics' frequency band-specific diagnostic value. Strikingly, connectivity during a single task-free EEG measurement predicted the level of patient recovery approximately 3 months later with 75% accuracy. Our findings show that spectral amplitude and connectivity track patient recovery in a longitudinal fashion, and these metrics are robust pathophysiological markers that can be used for the automated diagnosis and prognosis of disorders of consciousness. These metrics can be acquired inexpensively at bedside, and are fully independent of the patient's neurocognitive abilities. Lastly, our findings tentatively suggest that the relative preservation of thalamo-cortico-thalamic interactions may predict the later reemergence of awareness, and could thus shed new light on the pathophysiological processes that underlie disorders of consciousness.

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Using behavioral criteria, disorders of consciousness are often misdiagnosed

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We probed the diagnostic and prognostic value of task-free spectral EEG metrics

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Metrics changed non-linearly across recovery and predicted level of consciousness

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EEG connectivity predicted the level of patient recovery with 75% accuracy

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These metrics are fully independent of the patient's neurocognitive abilities

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

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

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

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

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

Unresponsive wakefulness syndrome: a new name for the vegetative state or apallic syndrome

BACKGROUND

Some patients awaken from coma (that is, open the eyes) but remain unresponsive (that is, only showing reflex movements without response to command). This syndrome has been coined vegetative state. We here present a new name for this challenging neurological condition: unresponsive wakefulness syndrome (abbreviated UWS).

DISCUSSION

Many clinicians feel uncomfortable when referring to patients as vegetative. Indeed, to most of the lay public and media vegetative state has a pejorative connotation and seems inappropriately to refer to these patients as being vegetable-like. Some political and religious groups have hence felt the need to emphasize these vulnerable patients' rights as human beings. Moreover, since its first description over 35 years ago, an increasing number of functional neuroimaging and cognitive evoked potential studies have shown that physicians should be cautious to make strong claims about awareness in some patients without behavioral responses to command. Given these concerns regarding the negative associations intrinsic to the term vegetative state as well as the diagnostic errors and their potential effect on the treatment and care for these patients (who sometimes never recover behavioral signs of consciousness but often recover to what was recently coined a minimally conscious state) we here propose to replace the name.

CONCLUSION

Since after 35 years the medical community has been unsuccessful in changing the pejorative image associated with the words vegetative state, we think it would be better to change the term itself. We here offer physicians the possibility to refer to this condition as unresponsive wakefulness syndrome or UWS. As this neutral descriptive term indicates, it refers to patients showing a number of clinical signs (hence syndrome) of unresponsiveness (that is, without response to commands) in the presence of wakefulness (that is, eye opening).

Persistent vegetative and minimally conscious states

The diagnosis and management of patients with persistent vegetative (PVS) and minimally conscious (MCS) states entail powerful medical, ethical and legal debates. The recent description of the MCS highlights the crucial role of unexpected and well-documented recoveries of cognitive functions. Functional neuroimaging has provided new insights for assessing neuropathology and cerebral activity in these patients, providing information on the presence, degree, and location of any residual brain function in patients with PVS or MCS. We present a review on this topic, emphasizing the clinical and neuroimaging assessment of these states, with some of our recent results in this area. We conclude that the development of rehabilitation techniques for patients with PVS and others suffering long-lasting effects of brain injury is a crucial challenge for actual and future generations of neuroscientists.