Clinimetric properties of the Nociception Coma Scale (-Revised): A systematic review

Short-term outcomes of early intensive neurorehabilitation for prolonged disorders of consciousness: A prospective cohort study

BACKGROUND

Advances in medical care have increased survival in people with severe brain injuries and with that the number of survivors with prolonged disorders of consciousness (PDOC) has increased. In the literature, early intensive neurorehabilitation (EIN) for people with PDOC is recommended to achieve the best possible outcomes.

OBJECTIVES

To evaluate the frequency and extent of recovery of consciousness, mortality, complications, pain and discomfort, and medication during a nationwide EIN programme in people with PDOC after acquired brain injury. We hypothesized that level of consciousness would improve in half of people with PDOC.

METHODS

Prospective cohort study. People with PDOC aged 16 years and older admitted to the EIN department centralized in a single rehabilitation centre in the Netherlands (Libra Rehabilitation & Audiology) were included. The EIN delivers a subacute medical level of care and rehabilitation for a maximum duration of 14 weeks. The outcome measures were level of consciousness (CRS-R), mortality, number of complications, medication and pain/discomfort (NCS-R).

RESULTS

Of the 104 people included, 68 % emerged to a minimal conscious state with command-following or higher during EIN and 44 % regained consciousness. Mortality during EIN was 6 %, and 50 % of deaths followed a non-treatment decision or withdrawal of life-sustaining treatment. Almost all participants had at least 1 medical complication, leading to hospital readmission for 30 %. 73 % showed no pain or discomfort. During EIN, cardiovascular medication and analgesics were reduced by 15 %.

CONCLUSIONS

During the EIN programme, a large percentage of people with PDOC regained at least a minimal conscious state or even consciousness. These outcomes and the frequent medical complications in these people suggest that intensive specialized care should be offered to all people with PDOC. The outcomes of this study might help health professionals to better inform the families of people with PDOC about the short-term prognosis of PDOC.

PROTOCOL REGISTRATION NUMBER

The Dutch Trial Register, NL 8138.

Assessing consciousness and cognition in disorders of consciousness

Detecting willful cognition in these patients is known to be challenging due to the patients' motor disabilities and high vigilance fluctuations but also due to the lack of expertise and use of adequate tools to assess these patients in specific settings. This review will discuss the main disorders of consciousness after severe brain injury, how to assess consciousness and cognition in these patients, as well as the challenges and tools available to overcome these challenges and reach an accurate diagnosis.

I Feel! Therefore, I Am from Pain to Consciousness in DOC Patients

Pain assessment and management in patients with disorders of consciousness (DOC) is a challenging and important aspect of care, with implications for detecting consciousness and promoting recovery. This narrative review explores the role of pain in consciousness, the challenges of pain assessment, pharmacological treatment in DOC, and the implications of pain assessment when detecting changes in consciousness. The review discusses the Nociception Coma Scale and its revised version, which are behavioral scales used to assess pain in DOC patients, and the challenges and controversies surrounding the appropriate pharmacological treatment of pain in these patients. Moreover, we highlight recent evidence suggesting that an accurate pain assessment may predict changes in the level of consciousness in unresponsive wakefulness syndrome/vegetative state patients, underscoring the importance of ongoing pain management in these patients.

Using AI to Detect Pain through Facial Expressions: A Review

Pain assessment is a complex task largely dependent on the patient's self-report. Artificial intelligence (AI) has emerged as a promising tool for automating and objectifying pain assessment through the identification of pain-related facial expressions. However, the capabilities and potential of AI in clinical settings are still largely unknown to many medical professionals. In this literature review, we present a conceptual understanding of the application of AI to detect pain through facial expressions. We provide an overview of the current state of the art as well as the technical foundations of AI/ML techniques used in pain detection. We highlight the ethical challenges and the limitations associated with the use of AI in pain detection, such as the scarcity of databases, confounding factors, and medical conditions that affect the shape and mobility of the face. The review also highlights the potential impact of AI on pain assessment in clinical practice and lays the groundwork for further study in this area.

Assessment and management of pain/nociception in patients with disorders of consciousness or locked-in syndrome: A narrative review

The assessment and management of pain and nociception is very challenging in patients unable to communicate functionally such as patients with disorders of consciousness (DoC) or in locked-in syndrome (LIS). In a clinical setting, the detection of signs of pain and nociception by the medical staff is therefore essential for the wellbeing and management of these patients. However, there is still a lot unknown and a lack of clear guidelines regarding the assessment, management and treatment of pain and nociception in these populations. The purpose of this narrative review is to examine the current knowledge regarding this issue by covering different topics such as: the neurophysiology of pain and nociception (in healthy subjects and patients), the source and impact of nociception and pain in DoC and LIS and, finally, the assessment and treatment of pain and nociception in these populations. In this review we will also give possible research directions that could help to improve the management of this specific population of severely brain damaged patients.

Understanding, detecting, and stimulating consciousness recovery in the ICU

Coma is a medical and socioeconomic emergency. Although underfunded, research on coma and disorders of consciousness has made impressive progress. Lesion-network-mapping studies have delineated the precise brainstem regions that consistently produce coma when damaged. Functional neuroimaging has revealed how mechanisms like "communication through coherence" and "inhibition by gating" work in synergy to enable cortico-cortical processing and how this information transfer is disrupted in brain injury. On the cellular level, break-down of intracellular communication between the layer 5 pyramidal cell soma and the apical dendritic part impairs dendritic information integration, with up-stream effects on microcircuits in local neuronal populations and on large-scale fronto-parietal networks, which correlates with loss of consciousness. A breakthrough in clinical concepts occurred when fMRI, and later EEG, studies revealed that 15% of clinically unresponsive patients in acute and chronic settings are in fact awake and aware, as shown by their command following abilities revealed by brain activation during motor and locomotion imagery tasks. This condition is now termed "cognitive motor dissociation." Furthermore, epidemiological data on coma were literally non-existent until recently because of difficulties related to case ascertainment with traditional methods, but crowdsourcing of family observations enabled the first estimates of how frequent coma is in the general population (pooled annual incidence of 201 coma cases per 100,000 population in the UK and the USA). Diagnostic guidelines on coma and disorders of consciousness by the American Academy of Neurology and the European Academy of Neurology provide ambitious clinical frameworks to accommodate these achievements. As for therapy, a broad range of medical and non-medical treatment options is now being tested in increasingly larger trials; in particular, amantadine and transcranial direct current stimulation appear promising in this regard. Major international initiatives like the Curing Coma Campaign aim to raise awareness for coma and disorders of consciousness in the public, with the ultimate goal to make more brain-injured patients recover consciousness after a coma. To highlight all these accomplishments, this paper provides a comprehensive overview of recent progress and future challenges related to understanding, detecting, and stimulating consciousness recovery in the ICU.

Pain assessment during physiotherapy and noxious stimuli in patients with disorders of consciousness: A preliminary study

Objectives

The primary purpose of this study is to determine whether patients with disorders of consciousness (DOC) (unresponsive wakefulness syndrome, UWS; minimally conscious state, MCS) experience pain during physiotherapy and noxious stimuli in a larger patient population.

Materials and methods

The patients’ level of consciousness was measured with the Coma Recovery Scale-Revised (CRS-R). Additionally, the Nociception Coma Scale-revised (NCS-R) was used to assess their pain response. The NCS-R total scores between UWS and MCS at baseline, physiotherapy and noxious stimulus were compared using the Mann-Whitney U test (Wilcoxon rank-sum test) and the Kruskal-Wallis H test with Bonferroni correction.

Results

The study enrolled 93 participants. There was a statistically significant difference in NCS-R total scores between the three conditions (H = 215.25, p < 0.001). At baseline, there was no statistically significant difference between MCS and UWS (U = 378, z = –1.35, p = 0.178). While there was a statistically significant difference between MCS and UWS during physiotherapy (U = 1,362, z = –3.06, p < 0.01) and under noxious stimuli (U = 5142.5, z = –11.22, p < 0.001).

Conclusion

Physiotherapy improved the activity responsiveness of DOC patients, and patients experienced less potential pain. However, some DOC patients, especially MCS patients, perceived pain under the noxious stimuli.

Pain in Persons with Disorders of Consciousness

Pain and suffering in persons with disorders of consciousness (DoC) remain poorly understood, frequently unaddressed or inadequately addressed, and controversial on numerous levels. This narrative literature review will address a number of critical issues germane to pain and suffering in this challenging group of patients, providing an introductory overview of the topic, perspectives on current knowledge regarding pain pathoanatomy and pathophysiology, and a review of common pain generators and factors that can lead to the chronifcation of pain. Caveats on bedside pain assessment challenges, as well as electrophysiologic and neuroimaging findings in these patients, will also be explored. Pain management techniques, including non-pharmacological and pharmacological, will be reviewed. Ethical considerations in the context of pain and suffering in persons with disorders of consciousness will round out the review prior to our concluding comments.

Nociceptive Response Is a Possible Marker of Evolution in the Level of Consciousness in Unresponsive Wakefulness Syndrome Patients

The Nociception Coma Scale (NCS) and its revised version (NCS-R) were used to evaluate behavioral responses to pain in non-communicative patients. We hypothesized that if patients demonstrate changes to their NCS(-R) scores over time, their evolving behavioral abilities could indicate a forthcoming diagnostic improvement with the Coma Recovery Scale-Revised (CRS-R). Forty-three Vegetative State/Unresponsive Wakefulness Syndrome (VS/UWS) patients were enrolled in the study. The patients were assessed weekly using the CRS-R and NCS(-R) for four consecutive weeks. The first assessment was within 10 days after hospitalization. The assessments were performed between 09:30 and 11:30 AM in a room with constant levels of humidity, light and temperature, as well as an absence of transient noise. Noxious stimuli were administered using a Newton-meter, with pressure applied to the fingernail bed for a maximum of 5 s unless interrupted by a behavioral response from subjects. Seventeen patients demonstrated improvements in their level of consciousness, 13 of whom showed significant behavioral changes through the NCS(-R) before being diagnosed with a Minimally Conscious State (MCS) according to the CRS-R. The behavioral changes observed using the NCS(-R) corresponded to a high probability of observing an improvement from VS/UWS to MCS. To characterize the increased likelihood of this transition, our results present threshold scores of ≥5 for the NCS (accuracy 86%, sensitivity 87%, and specificity 86%) and ≥3 for the NCS-R (accuracy 77%, sensitivity 89%, and specificity 73%). In conclusion, a careful evaluation of responses to nociceptive stimuli in DOC patients could constitute an effective procedure in assessing their evolving conscious state.

Addressing Pain for a Proper Rehabilitation Process in Patients With Severe Disorders of Consciousness

Consciousness constitutes a fundamental prerequisite in the individual appraisal and experience of pain. In the same way, a person needs to be able to report on pain perception. Patients who suffered a severe brain injury with disorders of consciousness (DOC) represent a spectrum of pathologies affecting patients' capacity to interact with the external world. In these patients, the most relevant aspects in response to pain are physiologic and behavioral. The treatments and management of pain are challenging issues in these patients, arising serious ethical concerns and bringing emotional load among medical staff, caregivers, and relatives. In this review, we report the importance of having a correct pain management in DOC patients, to individuate the best pharmacological treatment that can make the difference in detecting a behavioral response, indicative of a change in the level of consciousness, and in planning a more effective rehabilitative approach.

Outcome registry of early intensive neurorehabilitation in patients with disorders of consciousness: study protocol of a prospective cohort study

BACKGROUND

Prolonged disorders of consciousness (PDOC) may occur after severe brain injury. Two diagnostic entities are distinguished within PDOC: unresponsive wakefulness syndrome (UWS, previously known as vegetative state) and minimally conscious state (MCS). Patients with PDOC may benefit from early intensive neurorehabilitation (EIN). In the Netherlands, the EIN programme is provided by one designated expert rehabilitation centre and forms the starting point of a dedicated chain of specialised rehabilitation and care for this group. This study project, called DOCTOR: Disorders of Consciousness; Treatment and Outcomes Registry, sets up a registry and systematically investigates multiple short- and long-term outcomes of patients with PDOC who receive EIN.

METHODS

Single-centre prospective cohort study with a 2-year follow-up period. Patients with PDOC due to acute brain injury who receive EIN, aged 16 years and older are included. Measurements will take place at start EIN, in week 5, 10, and at discharge from the EIN programme (duration = max 14 weeks) and at week 28, 40, 52, and 104 after admission to the EIN programme, following patients through the health-care chain. Outcome measures are the changes over time in level of consciousness, using the Coma Recovery Scale-Revised; the frequency and type of medical complications; the mortality rate; level of disability, including the level of motor, cognitive, behavioural and emotional functioning; participation; and quality of life. Secondary outcomes include self-efficacy of caregivers, caregivers' strain and cost-effectiveness of the programme.

DISCUSSION

The DOCTOR study will provide insight in the recovery patterns and predictors of recovery for multiple outcomes in PDOC patients after following EIN. The results of the study will enable us to benchmark and improve EIN and the organisation of the health-care chain, both for patients with PDOC and for their families.

TRIAL REGISTRATION

Netherlands Trial Register, NL 8138 . Retrospectively registered 6 November 2019.

Update on diagnosis in disorders of consciousness

INTRODUCTION

New guidelines regarding the diagnosis of disorders of consciousness (DOC) (such as vegetative state and minimally conscious state) have recently been published by the American Academy of Neurology and the European Academy of Neurology. This follows an impressive number of prospective studies performed on DOC and recent multi-centric studies with larger sample size, which have gathered precious information on the recovery of cohort of patients through years and which now call for a better management of patients with DOC.

AREAS COVERED

This review will discuss recent updates on the clinical entities of DOC, the challenges for an accurate diagnosis and the last developments in diagnostic tools.

EXPERT OPINION

The authors will also discuss the impact of the new guidelines on their way of diagnosing patients and how diagnosis will most likely change in a near future.

European Academy of Neurology guideline on the diagnosis of coma and other disorders of consciousness

BACKGROUND AND PURPOSE

Patients with acquired brain injury and acute or prolonged disorders of consciousness (DoC) are challenging. Evidence to support diagnostic decisions on coma and other DoC is limited but accumulating. This guideline provides the state-of-the-art evidence regarding the diagnosis of DoC, summarizing data from bedside examination techniques, functional neuroimaging and electroencephalography (EEG).

METHODS

Sixteen members of the European Academy of Neurology (EAN) Scientific Panel on Coma and Chronic Disorders of Consciousness, representing 10 European countries, reviewed the scientific evidence for the evaluation of coma and other DoC using standard bibliographic measures. Recommendations followed the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. The guideline was endorsed by the EAN.

RESULTS

Besides a comprehensive neurological examination, the following suggestions are made: probe for voluntary eye movements using a mirror; repeat clinical assessments in the subacute and chronic setting, using the Coma Recovery Scale - Revised; use the Full Outline of Unresponsiveness score instead of the Glasgow Coma Scale in the acute setting; obtain clinical standard EEG; search for sleep patterns on EEG, particularly rapid eye movement sleep and slow-wave sleep; and, whenever feasible, consider positron emission tomography, resting state functional magnetic resonance imaging (fMRI), active fMRI or EEG paradigms and quantitative analysis of high-density EEG to complement behavioral assessment in patients without command following at the bedside.

CONCLUSIONS

Standardized clinical evaluation, EEG-based techniques and functional neuroimaging should be integrated for multimodal evaluation of patients with DoC. The state of consciousness should be classified according to the highest level revealed by any of these three approaches.

Development of a Measure of Nociception for Patients With Severe Brain Injury

OBJECTIVES

Severe brain injury is often accompanied by painful comorbidities and by concurrent limitations in the ability to report pain. Assessment of nociception aids diagnosis and helps balance reduction in suffering with avoidance of sedating medications. Existing assessment methods confound patients' level of consciousness with the intensity of nociception, complicating pain assessment as consciousness evolves. We sought to develop a measure of nociception that is independent of the level of consciousness.

MATERIALS AND METHODS

We identified 15 behavioral and physiological items likely to be sensitive to nociception. We rated noncommunicative patients with traumatic brain injury in 4 different activities predicted to modulate nociception, on each of 2 days, one randomly chosen for acetaminophen administration. The level of consciousness and level of agitation were also measured.

RASCH ANALYSIS

Rasch analysis was used to assess item fit to an underlying dimension of nociception.

RESULTS

Five items that demonstrated poor fit to the dimension were removed. The 10 remaining items demonstrated acceptable fit. Scores were significantly influenced by activity and analgesic treatment and were largely independent of measures of consciousness and agitation. Accurate scores could be obtained in about 10 minutes and were robust to missing data.

DISCUSSION

The results provide evidence that the Brain Injury Nociception Assessment Measure (BINAM) is reliable and feasible to administer. It can assess the intensity of nociception largely independent of the level of consciousness. Further research is warranted on the impact of BINAM use on the care of patients with severe traumatic brain injury.

Narrative review of acute post-craniotomy pain. Concept and strategies for prevention and treatment of pain

The aim of this narrative review is to confirm that acute pain after craniotomy is frequent and presents with moderate to severe intensity. We also highlight the importance of not only treating post-craniotomy pain, but also of preventing it in order to reduce the incidence of chronic pain. Physicians should be aware that conventional postoperative analgesics (non-steroidal anti-inflammatory, paracetamol, cyclooxygenase inhibitors 2, opioids) are not the only options available. Performing a scalp block prior to surgical incision or after surgery, the use of intraoperative dexmedetomidine, and the perioperative administration of pregabalin are just some alternatives that are gaining ground. The management of post-craniotomy pain should be based on perioperative multimodal analgesia in the framework of an "enhaced recovery after surgery" (ERAS) approach.

Nociception Coma Scale-Revised: Nurses' Experience in Clinical Practice

BACKGROUND

The Nociception Coma Scale-Revised (NCS-R) is a rating scale developed and validated for measurement of nociception and pain among patients with brain injuries in unresponsive wakefulness syndrome or minimally conscious state. However, little is known about its use in daily clinical practice.

AIMS

The aim of this study was to explore clinical experience with the NCS-R by means of focus group interviews with nurses and nurse assistants in a subacute rehabilitation ward for patients with severe brain injuries.

DESIGN

Qualitative focus group interview study.

SETTINGS

Department for highly specialized neurorehabilitation for patients with severe brain injuries.

PARTICIPANTS/SUBJECTS

Nurses and nurse assistants.

METHODS

In total, 12 experienced registered nurses and nurse assistants participated in two recorded focus group interviews. The participants were selected from the subacute neurorehabilitation ward on the following criteria: Employed at the ward for at least 11 months and being introduced to and having experience with using the NCS-R in own patients for a minimum period of 6 months. An inductive qualitative analysis was conducted by reading the interview text through several times, and meaning units were defined first separately and later jointly between the authors. Then meaning units were coded and categorized into subthemes and themes.

RESULTS

We found three themes, general relevance of the NCS-R, NCS-R versus level of consciousness, and overall assessment of pain in patients with disorders of consciousness, with a total of eight subthemes.

CONCLUSIONS

The content and subscales of the NCS-R are relevant for pain assessment in patients with severe brain injury in subacute rehabilitation. However, with the present cutoff value at 4 points, challenges are associated with using NCS-R, especially in patients with unresponsive wakefulness syndrome because they are at risk of not being assessed with respect to pain.