The Full Outline of UnResponsiveness (FOUR) Score and Its Use in Outcome Prediction: A Scoping Systematic Review of the Adult Literature

Combining quantified EEG with clinical measures to better predict outcomes of acute disorders of consciousness

OBJECTIVE

To explore the application of the neuronal recovery model (i.e., the ABCD model derived from EEG power spectral analysis) in forecasting outcomes for patients with acute disorders of consciousness (DOC).

METHODS

Patients with acute DOC were enrolled, and clinical assessments, including the Glasgow Coma Scale (GCS), Full Outline of UnResponsiveness (FOUR), and Coma Recovery Scale-Revised (CRS-R) scores, along with electroencephalography (EEG), were documented on the first day post-enrollment. The ABCD model, derived from EEG power spectral data reflecting frequency bands, categorized brain activity into four distinct groups (A, B, C, D). Outcome prognoses were evaluated using the Glasgow Outcome Scale-Extended (GOSE) six months after enrollment. Statistical analyses were performed to assess the correlation between the ABCD model and clinical assessments, and to investigate the predictive value of EEG and clinical assessments for the long-term prognosis.

RESULTS

A total of 93 patients with acute DOC were included; the median age was 64 years (interquartile range 52, 72), of which 52 patients had favorable outcomes. Significant correlations were observed between the ABCD model and both the FOUR and CRS-R scores. The CRS-R and ABCD model demonstrated relatively good predictive value for six-month prognoses, with Area Under the Curve (AUC) values of 0.695 and 0.678, respectively (P < 0.05). Furthermore, the combination of the CRS-R score and ABCD model exhibited the highest predictive value with an AUC of 0.746.

CONCLUSIONS

The ABCD model effectively predicted the prognosis of patients with acute DOC in combination with CRS-R.

Beyond Glasgow Coma Scale: Prehospital prediction of traumatic brain injury

INTRODUCTION

Early identification of traumatic brain injury followed by timely, targeted treatment is essential. We aimed to establish the ability of prehospital Glasgow Coma Scale score alone and combined with vital signs to predict hospital-diagnosed traumatic brain injury.

METHODS

This study included adults from the 2017-2020 Trauma Quality Improvement Program data set with blunt mechanism. We calculated test characteristics of prehospital Glasgow Coma Scale score ≤12 alone and Glasgow Coma Scale score combined with heart rate and systolic blood pressure for predicting (1) any traumatic brain injury and (2) moderate to severe traumatic brain injury. Diagnostic performances were calculated in all patients and older adults (≥55 years). We used decision curve analysis to determine the net diagnostic benefit of prehospital Glasgow Coma Scale score combined with heart rate + systolic blood pressure over Glasgow Coma Scale score alone.

RESULTS

Of 1,687,336 patients, 39.1% had any traumatic brain injury, 3.7% had moderate to severe traumatic brain injury, and 9.1% had a prehospital Glasgow Coma Scale score ≤12. Prehospital Glasgow Coma Scale score ≤12 alone had a sensitivity 83.1%, specificity 93.7%, negative predictive value 99.3%, and positive predictive value 33.7% for predicting moderate to severe traumatic brain injury. Adding prehospital heart rate <65/min and systolic blood pressure >150 mm Hg to Glasgow Coma Scale score ≤12 improved the positive predictive value for moderate to severe traumatic brain injury (55.3%), with a preserved negative predictive value of 96.4%. Decision curve analysis showed the traumatic brain injury prediction model including prehospital heart rate and systolic blood pressure had the greatest net benefit across most threshold probabilities.

CONCLUSION

Less than a third of adult blunt trauma patients with a prehospital Glasgow Coma Scale score ≤12 have moderate to severe traumatic brain injury. Supplementing Glasgow Coma Scale score with prehospital vital signs improves diagnostic accuracy, potentially by filtering out patients with altered consciousness due to shock. Future work should better identify patients for traumatic brain injury-specific treatments in prehospital settings, including triage destination.

Comparison of Glasgow Coma Scale and Full Outline of UnResponsiveness score to assess the level of consciousness in patients admitted to intensive care units and emergency departments: A quantitative systematic review

OBJECTIVES

We aimed to investigate the reliability and validity of the Glasgow Coma Scale (GCS) and the Full Outline of UnResponsiveness (FOUR) score used by nurses and physicians to assess the level of consciousness in patients admitted to intensive care units (ICUs) and emergency departments (EDs).

REVIEW METHOD USED

This systematic review was guided by the Cochrane Handbook for Systematic Reviews of Interventions and followed the reporting standards of the Preferred Reporting Items for Systematic Review and Meta-Analysis Statement.

DATA SOURCES

A systematic search was conducted using the following databases: CINAHL, MEDLINE, and EMBASE.

REVIEW METHODS

All authors performed the study selection process, data collection, and assessment of quality. The following psychometric properties were addressed: inter-rater reliability, internal consistency, and construct validity.

RESULTS

Six articles were included. The GCS and the FOUR scores demonstrated excellent reliability and very strong validity when used by nurses and physicians to assess the level of consciousness in patients admitted to the ICU and ED. The FOUR score demonstrated slightly higher overall reliability and validity than the GCS.

CONCLUSION

This systematic review indicates that the FOUR score is especially suitable for assessing the level of consciousness in patients admitted to the ICU and ED. The FOUR score demonstrated higher reliability and validity than the GCS, making it a promising alternative assessment scale, despite the GCS's longstanding use in clinical practice.

Definitions, diagnostic criteria, and clinical assessment scales in disorders of consciousness

Disorders of consciousness (DoC) are neurologic conditions characterized by severe alteration in level of consciousness. Categories of DoC may include coma, unresponsive wakefulness syndrome/vegetative state, minimally conscious state (MCS; can be further categorized into MCS+ and MCS- based on the presence or absence of language-related behaviors), emergence from MCS, confusional state or delirium, and cognitive motor dissociation (CMD). CMD is a recently defined condition in which the patient fails to demonstrate observable behavioral responses on bedside assessment but demonstrates covert cognitive processing on functional imaging or EEG studies. Accurate differential diagnosis in DoC is aided by adherence to basic principles of assessment, including use of standardized assessment scales. Clinicians should serially administer standardized assessment tools to ensure valid interpretation of results and optimize diagnostic accuracy. Among standardized scales, the Coma Recovery Scale-Revised is most widely used and has the strongest psychometric validity in assessing DoC. The Neurocritical Care Society's Curing Coma Campaign has proposed a slate of DoC common data elements that is expected to improve the consistency and precision of DoC research.

Complex auditory regularity processing across levels of consciousness in coma: Stage 1 Registered Report

A key question for the scientific study of consciousness is whether it is possible to identify specific features in brain activity that are uniquely linked to conscious experience. This question has important implications for the development of markers to detect covert consciousness in unresponsive patients. In this regard, many studies have focused on investigating the neural response to complex auditory regularities. One noteworthy example is the local global paradigm, which allows for the investigation of auditory regularity encoding at the 'global' level, based on the repetition of groups of sounds. The inference of global regularities is thought to depend on conscious access to such complex auditory stimuli as mostly shown in chronic stages of disorders of consciousness patients. However, whether global regularity encoding can identify covert consciousness along the consciousness spectrum including earlier stages of these disorders remains controversial. Here, we aim to fill this gap by investigating whether the inference of global auditory regularities can occur in acute coma, in the absence of consciousness, and how this may be modulated by the severity of the patients' clinical condition and consciousness level measured using the Full Outline of UnResponsiveness (FOUR) score. We will acquire 63-channel continuous electroencephalography to measure the neural response to global auditory regularity in comatose patients (N = 30) during the first day after cardiac arrest, when patients are unconscious, sedated and under normothermia, and during the second day (with reduced or absent sedation and body temperature control). We hypothesize that global regularity encoding will persist in the absence of consciousness independent of patient outcome, observed as above chance decoding of the neural response to global regularities using multivariate decoding analyses. We further hypothesize that decoding performance will positively correlate with the FOUR score, which indexes consciousness level, and typically improves between the first and second day after coma onset following cardiac arrest in patients with favourable outcome. In an exploratory analysis, we will also evaluate whether global regularity encoding may be influenced by the patients' clinical management, specifically sedation, also shown to affect global deviance detection. Our results will shed light on the neurophysiological correlates of complex auditory regularity processing in unconscious patients and on the link to residual levels of consciousness during the underexplored state of coma upon the first days after cardiac arrest.

The Predictive Validity of the Full Outline of UnResponsiveness Score Compared to the Glasgow Coma Scale in the Intensive Care Unit: A Systematic Review

The Full Outline of UnResponsiveness (FOUR) score was developed to overcome the limitations of the Glasgow Coma Scale (GCS) when assessing individuals with impaired consciousness. We sought to review the evidence regarding the predictive validity of the GCS and FOUR score in intensive care unit (ICU) settings. This review was prospectively registered in PROSPERO (CRD42023420528). Systematic searches of CINAHL, MEDLINE, and Embase were undertaken. Prospective observational studies were included if both GCS and FOUR score were assessed in adults during ICU admission and if mortality and/or validated functional outcome measure scores were collected. Studies were excluded if they exclusively investigated patients with traumatic brain injury. Screening, data extraction, and quality assessment using the Quality in Prognosis Studies tool were conducted by two reviewers. Twenty studies of poor to moderate quality were included. Many studies only included patients with neurological illness and excluded sedated patients, despite high proportions of intubated patients. The FOUR score achieved higher area under the receiver operating characteristic curve values for mortality prediction compared with the GCS, and the FOUR score achieved significantly higher area under the receiver operating characteristic curve values for predictions of ICU mortality. Both coma scales showed similar accuracy in predicting "unfavorable" functional outcome. The FOUR score appeared to be more responsive than the GCS in the ICU, as most patients with a GCS score of 3 obtained FOUR scores between 1 and 8 due to preserved brainstem function. The FOUR score may be superior to the GCS for predicting mortality in ICU settings. Further adequately powered studies with clear, reliable methods for assessment of index and outcome scores are required to clarify the predictive performance of both coma scales in ICUs. Inclusion of sedated patients may improve generalizability of findings in general ICU populations.

Meningovascular Syphilis Presenting as Acute Ischemic Stroke in an HIV + Young Adult: A Case Report and a Brief Literature Review

Background

Meningovascular syphilis, a distinct classification of neurosyphilis, has gained attention for its association with cerebral ischemia, particularly among individuals living with HIV. This unique manifestation of syphilis affects the meningeal and vascular structures of the central nervous system, leading to cerebrovascular complications. In this case report, we present the case of a young man diagnosed with neurosyphilis and HIV after presenting with an ischemic stroke. We discuss the challenges associated with diagnosing neurosyphilis, given its frequent atypical presentations that can mimic other diseases. Furthermore, we explore the management approach for these coexisting conditions.

Case Presentation

A right-handed male patient presented with a sudden paresis of the right upper and lower extremities, along with facial deviation to the left, and demonstrated low verbal output, limitation in constructing sentences, and conveying thoughts or ideas effectively. Upon admission, the patient's neurological examination revealed a FOUR coma scale of 16. He exhibited motor aphasia, right facial paralysis sparing the forehead, and right upper and lower extremity spastic hemiparesis with a strength of 3 out of 5 on the Medical Research Council scale. The Plantar reflex was positive on the affected side. Brain magnetic resonance imaging revealed left middle cerebral artery infarction (cortical and lenticulostriate territory acute infarction).

Conclusion

This case highlights the need for treating physician to have a high index of suspicion towards meningovascular syphilis as a potential cause of stroke in young individuals. This is crucial, especially when there is also a concurrent HIV infection, as it requires specific treatment.

Comparison of Glasgow Coma Scale and Full Outline of UnResponsiveness score for prediction of in-hospital mortality in traumatic brain injury patients: a systematic review and meta-analysis

BACKGROUND

Currently, Glasgow Coma Scale (GCS) is used to assess patients' level of consciousness. Although this tool is highly popular in clinical settings, it has various limitations that reduce its applicability in certain situations. This had led researchers to look for alternative scoring systems. This study aims to compare the value of GCS and Full Outline of UnResponsiveness (FOUR) score for prediction of mortality in traumatic brain injury (TBI) patients through a systematic review and meta-analysis.

METHOD

Online databases of Medline, Embase, Scopus, and Web of Science were searched until the end of July 2022 for studies that had compared GCS and FOUR score in TBI patients. Interested outcomes were mortality and unfavorable outcome (mortality + disability). Findings are reported as area under the curve (AUC) sensitivity, specificity, and diagnostic odds ratio.

RESULTS

20 articles (comprised of 2083 patients) were included in this study. AUC of GCS and FOUR score for prediction of in-hospital mortality after TBI was 0.92 (95% CI 0.80-0.91) and 0.91 (95% CI 0.88-0.93) respectively. The diagnostic odds ratio of the two scores for prediction of in-hospital mortality after TBI was 44.51 (95% CI 23.58-84.03) for GCS and 45.16 (95% CI 24.25-84.09) for FOUR score. As for prediction of unfavorable outcome after TBI, AUC of GCS and FOUR score were 0.95 (95% CI 0.93 to 0.97) and 0.93 (95% CI 0.91-0.95), respectively. The diagnostic odds ratios for prediction of unfavorable outcome after TBI were 66.31 (95% CI 35.05-125.45) for GCS and 45.39 (95% CI 23.09-89.23) for FOUR score.

CONCLUSION

Moderate level of evidence showed that the value of GCS and FOUR score in the prediction of in-hospital mortality and unfavorable outcome is comparable. The similar performance of these scores in assessment of TBI patients gives the medical staff the option to use either one of them according to the situation at hand.

State-of-the-Art Evaluation of Acute Adult Disorders of Consciousness for the General Intensivist

OBJECTIVES

To provide a concise review of knowledge and practice pertaining to the diagnosis and initial management of unanticipated adult patient disorders of consciousness (DoC) by the general intensivist.

DATA SOURCES

Detailed search strategy using PubMed and OVID Medline for English language articles describing adult patient acute DoC diagnostic evaluation and initial management strategies including indications for transfer.

STUDY SELECTION

Descriptive and interventional studies that address acute adult DoC, their evaluation and initial management, indications for transfer, as well as outcome prognostication.

DATA EXTRACTION

Relevant descriptions or studies were reviewed, and the following aspects of each manuscript were identified, abstracted, and analyzed: setting, study population, aims, methods, results, and relevant implications for adult critical care practice.

DATA SYNTHESIS

Acute adult DoC may be categorized by etiology including structural, functional, infectious, inflammatory, and pharmacologic, the understanding of which drives diagnostic investigation, monitoring, acute therapy, and subsequent specialist care decisions including team-based local care as well as intra- and inter-facility transfer.

CONCLUSIONS

Acute adult DoC may be initially comprehensively addressed by the general intensivist using an etiology-driven and team-based approach. Certain clinical conditions, procedural expertise needs, or resource limitations inform transfer decision-making within a complex care facility or to one with greater complexity. Emerging collaborative science helps improve our current knowledge of acute DoC to better align therapies with underpinning etiologies.

Functional NIRS to detect covert consciousness in neurocritical patients

OBJECTIVE

This pilot study assesses the feasibility to detect covert consciousness in clinically unresponsive patients by means of functional near infrared spectroscopy (fNIRS) in a real intensive care unit setting. We aimed to verify if the hemodynamic response to familiar music measured with fNIRS varies according to the level consciousness of the patients.

METHODS

22 neurocritical patients and 6 healthy controls were included. The experiment consisted in 3 subsequent blocks including a first resting state recording, a period of music playback and a second resting state recording. fNIRS measurement were performed on each subject with two optodes on the forehead. Main oscillatory frequencies of oxyhemoglobin signal were analyzed. Spectral changes of low frequency oscillations (LFO) between subsequent experimental blocks were used as a marker of cortical response. Cortical response was compared to the level of consciousness of the patients and their functional outcome, through validated clinical scores.

RESULTS

Cortical hemodynamic response to music on the left prefrontal brain was associated with the level of consciousness of the patients and with their clinical outcome after three months.

CONCLUSIONS

Variations in LFO spectral power measured with fNIRS may be a new marker of cortical responsiveness to detect covert consciousness in neurocritical patients. Left prefrontal cortex may play an important role in the perception of familiar music.

SIGNIFICANCE

We showed the feasibility of a simple fNIRS approach to detect cortical response in the real setting of an intensive care unit.

Stroke Scales as Assessment Tools in Emergency Settings: A Narrative Review

In the last 20 years, substantial improvements have been made in stroke recanalization treatment. Good outcomes after modern reperfusion treatment require the rapid and accurate identification of stroke patients. Several stroke rating scales are available or have been proposed for the early recognition of stroke and the evaluation of stroke severity and outcome. This review aims to provide an overview of commonly used stroke scales in emergency and clinical settings. The most commonly used scale in a prehospital setting for stroke recognition is the Face, Arms, Speech, Time (FAST) test. Among many prehospital stroke scales, the Los Angeles Prehospital Stroke Screen has the highest sensitivity and specificity for confirming stroke diagnosis. The National Institutes of Health Stroke Scale (NIHSS) is the most recommended tool for the evaluation of stroke patients in hospital settings and research, and it has two variants: the shortened NIHSS for Emergency Medical Service and the modified NIHSS. The evaluation of comatose patients usually involves assessment with the Glasgow Coma Scale, which is very useful in patients with hemorrhagic stroke or traumatic brain injury. In patients with subarachnoid hemorrhage, the outcome is usually accessed with the Hunt and Hess scale. A commonly used tool for stroke outcome evaluation in clinical/hospital settings and research is the modified Rankin scale. The tools for disability evaluation are the Barthel Index and Functional Independence Measure.

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.

Comparison of the prognostic value of coma scales among health-care professionals: a prospective observational study

OBJECTIVE

To assess the predictive value of the Full Outline of Unresponsiveness (FOUR) Score and the Glasgow Coma Scale (GCS), investigating whether they are comparable in predicting short- and long-term functional outcome and if their predictive ability remains unaffected by the raters' background and experience.

METHODS

Patients treated in the Neurosurgery Department and the Intensive Care Unit in need for consciousness monitoring were assessed between October 1st, 2018, and December 31st, 2020, by four raters (two consultants, a resident and a nurse) using the two scales on admission and at discharge. Outcome was recorded at discharge and at 6 months. Areas under the receiver operating characteristic curve (AUCs) were calculated for the prediction of mortality and poor outcome, and the identification of coma.

RESULTS

Eighty-six patients were included. AUCs values were > 0.860 for all outcomes and raters. No significant differences were noted between the two scales. Raters' experience did not affect the scales' predictive value. Both scales showed excellent accuracy in identifying comatose patients (AUCs > 0.950). The difference between admission and discharge values was not a reliable predictor.

CONCLUSION

Both the FOUR Score and GCS are reliable predictors of short- and long-term outcome, with no clear superiority among them. The application of the FOUR Score by inexperienced raters is equally reliable, without influencing negatively the predictive value.

Clinimetric study and review of the Reaction Level Scale

OBJECTIVES

Although the Reaction Level Scale (RLS) is still used for the assessment of the level of consciousness in distinct centers, its clinical characteristics and significance have been incompletely researched. In the current study, the clinimetric properties, the prognostic value, and the impact of the raters' background on the application of the RLS, in comparison with the Glasgow Coma Scale (GCS), are investigated.

MATERIALS AND METHODS

A systematic review on the available clinical evidence for the RLS was first carried out. Next, the RLS was translated into Greek, and patients with neurosurgical pathologies in need of consciousness monitoring were independently assessed with both RLS and GCS, by four raters (two consultants, one resident, and one nurse) within one hour. Interrater reliability, construct validity, and predictive value (mortality and poor outcome, at discharge and at 6 months) were evaluated.

RESULTS

Literature review retrieved 9 clinimetric studies related to the RLS, most of low quality, indicating that the scale has not been thoroughly studied. Both versions of the RLS (original and modified) showed high interrater reliability (κ_w >0.80 for all pairs of raters), construct validity (Spearman's p > .90 for all raters), and prognostic value (areas under the curve >0.85 for all raters and outcomes). However, except for broader patients' coverage, it failed to show any advantage over the GCS.

CONCLUSIONS

The RLS has not succeeded in showing any advantage over the GCS in terms of reliability and validity. Available evidence cannot justify its use in clinical practice as a substitute to the widely applied GCS.

Effectiveness of the Full Outline of UnResponsiveness Score in Patients With Acute Ischemic Stroke

Background

Predicting the mortality and prognosis of patients with stroke is one of the commonly studied topics. Various scoring systems have been used in this regard. One of them is the Full Outline of UnResponsiveness (FOUR) score. In this study, we aimed to investigate the utility of the FOUR scores in terms of their ability to predict hospital stay duration and mortality in patients who were diagnosed with ischemic stroke upon their admission to the emergency department.

Methods

Our study is a prospective observational study. Patients who were admitted to the emergency department of a tertiary hospital and diagnosed with ischemic stroke between August 1, 2020, and August 1, 2021, were included in the study. The inclusion criteria were as follows: being over the age of 18, being diagnosed with ischemic stroke, having symptoms that started within the last 48 hours, and patient consent approved by the patients themselves or their relatives. The patients were divided into two groups according to the FOUR scores (FOUR score = 16 and FOUR score < 16). Patients’ demographic information, vital parameters, symptoms, time to admission, comorbidities, laboratory parameters, length of hospitalization, mortality, and Glasgow Coma Scale (GCS), FOUR, and National Institutes of Health Stroke Scale (NIHSS) scores were recorded.

Results

A total of 79 patients were included in the current study, of which 47 (59.5%) were male. The patients included in the present study had a mean age of 66 ± 13 years. When the two groups of patients with a FOUR score of 16 and a FOUR score of below 16 were compared, the mean platelet count was found to be 248 ± 70 × 10³/L in the former group and 170 ± 84 × 10³/L in the latter (p = 0.004). Sixty-five (91.5%) of the patients in the group with a FOUR score of 16 and three (37.5%) of the patients in the group with a FOUR score of less than 16 stayed for more than six hours in the hospital (p < 0.001). When the patients were evaluated for intensive care unit (ICU) admission rates, five (62.5%) patients with a FOUR score of <16 were admitted to the ICU. This rate was 2.8% (n = 2) in the group of patients with a FOUR score of 16 and was found to be significantly lower (p < 0.001).

Conclusion

The FOUR score was found to be useful in predicting the ICU admission rate of patients with ischemic stroke. It has also been shown that the admission time was shorter in patients with a lower FOUR score, and platelet counts were also lower in this group.

Understanding Disorders of Consciousness: Opportunities for Critical Care Nurses

BACKGROUND

Disorders of consciousness are powerful predictors of outcomes including mortality among critically ill patients. Encephalopathy, delirium, and coma are disorders of consciousness frequently encountered by critical care nurses but often classified incorrectly.

OBJECTIVE

To provide a greater understanding of disorders of consciousness and to provide standardized assessments and nursing interventions for these disorders.

METHODS

A literature search was conducted by using the terms consciousness, mental status, awareness, arousal, wakefulness, assessment, disorders of consciousness, delirium, encephalopathy, coma, vegetative state, and minimal consciousness. Articles were published in the past 10 years in CINAHL and PubMed. Articles were excluded if they were not in English or directly related to caring for patients with a disorder of consciousness. The remaining 142 articles were evaluated for inclusion; 81 articles received full review.

RESULTS

A disorder of consciousness signifies that the threshold for compensation has been surpassed with potentially irreversible damage. Altered thalamocortical interactions and reduced cortical activity impair communication networks across the various parts of the brain, causing a disturbance in consciousness.

DISCUSSION

The cue-response theory is a model that describes the process and impact of nursing care on recovery from acute brain injury. Appropriate standardized assessments and interventions must be used to manage altered levels of consciousness in critically ill patients.

CONCLUSIONS

Paying close attention to neurological changes and monitoring them with standardized assessments are critical to implementing early measures to prevent complications.

Cross-Cultural Adaptation and Validation of the Greek Version of the "Full Outline of Unresponsiveness Score": A Prospective Observational Clinimetric Study in Neurosurgical Patients

Background

The Full Outline of Unresponsiveness (FOUR) score is a clinical instrument for the assessment of consciousness which is gradually gaining ground in clinical practice, as it incorporates more complete neurological information than the Glasgow Coma Scale (GCS). The main objectives of the current study were the following: (1) translate and cross-culturally adapt the FOUR score into Greek; (2) evaluate its clinimetric properties, including interrater reliability, internal consistency, and construct validity; and (3) evaluate the reliability of assessments among health care professionals with different levels of experience and training.

Methods

The FOUR score was initially translated into Greek. Next, patients with neurosurgical pathologies in need of consciousness monitoring were independently assessed with the GCS and FOUR score within one hour by four raters who had different levels of experience and training (two board-certified neurosurgeons, a neurosurgery resident, and a registered nurse). Interrater reliability, internal consistency, and construct validity were evaluated for the scales using weighted Cohen’s κ (κ_w) and intraclass correlation coefficients (ICC), Cronbach’s α and Spearman’s ρ values, respectively.

Results

A total of 408 assessments were performed for 99 patients. The interrater reliability was excellent for both the FOUR score (ICC = 0.941) and GCS (ICC = 0.936). The values of κ_w exceeded 0.90 for all pairs, suggesting that the FOUR score can be reliably applied by raters with varying experience. Among the scales’ components, FOUR score’s brainstem and respiratory items showed the lowest, yet high enough (κ_w > 0.60), level of agreement. The interrater reliability remained excellent (κ_w > 0.85, ICC > 0.90) for all diagnosis and age groups, with a trend toward higher FOUR score values in the most severe cases (ICC = 0.813 vs. 0.723). Both the FOUR score and GCS showed high internal consistency (Cronbach’s α > 0.70 for all occasions). The FOUR score correlated strongly with GCS (Spearman’s ρ > 0.90 for all raters), suggesting high construct validity.

Conclusions

The Greek version of the FOUR score is a valid and reliable tool for the clinical assessment of patients with disorders of consciousness. It can be applied successfully by nurses, residents, and specialized physicians. Therefore, its use by medical practitioners with different levels of experience and training is strongly encouraged.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12028-021-01342-w.

Amantadine and Modafinil as Neurostimulants During Post-stroke Care: A Systematic Review

Amantadine and modafinil are neurostimulants that may improve cognitive and functional recovery post-stroke, but the existing study results vary, and no comprehensive review has been published. This systematic review describes amantadine and modafinil administration practices post-stroke, evaluates timing and impact on clinical effectiveness measures, and identifies the incidence of potential adverse drug effects. A librarian-assisted search of the MEDLINE (PubMed) and EMBASE databases identified all English-language publications with "amantadine" or "modafinil" in the title or abstract from inception through February 1, 2020. Publications meeting predefined Patient, Intervention, Comparator, Outcome (PICO) criteria were included: Patients (≥ 18 years of age post-stroke); Intervention (amantadine or modafinil administration); Comparison (pretreatment baseline or control group); Outcomes (cognitive or functional outcome). Amantadine and modafinil administration practices, cognitive and functional outcomes, and incidence of potential adverse drug effects were collected following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidance. Quantitative analyses were not performed due to heterogeneity in the clinical effectiveness measures; descriptive data are presented as number (percent) or median (interquartile range). Of 12,620 publications initially identified, 10 amantadine publications (n = 121 patients) and 12 modafinil publications (n = 120 patients) were included. Amantadine was initiated 39 (16, 385) days post-stroke, with most common initial doses of 100 mg once or twice daily (range 100-200 mg/day), and final daily dose of 200 (188, 200) mg/day. Modafinil was initiated 170 (17, 496) days post-stroke, with initial and final daily doses of 100 (100, 350) mg/day and 200 (100, 350) mg/day, respectively. The most common indication was consciousness disorders for amantadine (n = 3/10 publications; 30%) and fatigue for modafinil (n = 5/12; 42%). Forty unique clinical effectiveness measures (1.8 per study) with 141 domains (6.4 per study) were described across all studies. A positive response in at least one clinical effectiveness measure was reported in 70% of amantadine publications and 83% of modafinil publications. Only one publication each for amantadine (10%; n = 5 patients) and modafinil (8%; n = 21 patients) studied acutely hospitalized or ICU patients; both were randomized studies showing improvements in neurocognitive function for amantadine and fatigue for modafinil. Potential adverse drug effects were reported in approximately 50% of publications, most commonly visual hallucinations with amantadine (2% of patients) and dizziness (5% of patients) and dry eyes or mouth (5% of patients). Amantadine and modafinil may improve cognitive and functional recovery post-stroke, but higher-quality data are needed to confirm this conclusion, especially in the acute care setting.

Delayed awakening in neurocritical care

Delayed awakening is defined as a persistent disorder of arousal or consciousness 48 to 72h after sedation interruption in critically ill patients. Delayed awakening is either a component of coma or delirium. It results in longer hospital stays and increased mortality. It is therefore a diagnostic, therapeutic and prognostic emergency. In severe brain injured patients, delayed awakening may be related to the primary neurological injury or to secondary systemic insults related to organ failure associated with intensive care. In the present review, we propose diagnostic, therapeutic and prognostic algorithms for managing delayed awaking in neuro-ICU brain injured patients.

A Precision Medicine Framework for Classifying Patients with Disorders of Consciousness: Advanced Classification of Consciousness Endotypes (ACCESS)

BACKGROUND

Consciousness in patients with brain injury is traditionally assessed based on semiological evaluation at the bedside. This classification is limited because of low granularity, ill-defined and rigid nomenclatures incompatible with the highly fluctuating nature of consciousness, failure to identify specific brain states like cognitive motor dissociation, and neglect for underlying biological mechanisms. Here, the authors present a pragmatic framework based on consciousness endotypes that combines clinical phenomenology with all essential physiological and biological data, emphasizing recovery trajectories, therapeutic potentials and clinical feasibility.

METHODS

The Neurocritical Care Society's Curing Coma Campaign identified an international group of experts who convened in a series of online meetings between May and November 2020 to discuss and propose a novel framework for classifying consciousness.

RESULTS

The expert group proposes Advanced Classification of Consciousness Endotypes (ACCESS), a tiered multidimensional framework reflecting increasing complexity and an aspiration to consider emerging and future approaches. Tier 1 is based on clinical phenotypes and structural imaging. Tier 2 adds functional measures including EEG, PET and functional MRI, that can be summarized using the Arousal, Volition, Cognition and Mechanisms (AVCM) score (where "Volition" signifies volitional motor responses). Finally, Tier 3 reflects dynamic changes over time with a (theoretically infinite) number of physiologically distinct states to outline consciousness recovery and identify opportunities for therapeutic interventions.

CONCLUSIONS

Whereas Tiers 1 and 2 propose an approach for low-resource settings and state-of-the-art expertise at leading academic centers, respectively, Tier 3 is a visionary multidimensional consciousness paradigm driven by continuous incorporation of new knowledge while addressing the Curing Coma Campaign's aspirational goals.

[GCS score combined with CT score and serum S100B protein level Can evaluate severity and early prognosis of acute traumatic brain injury]

OBJECTIVE

To explore the value of Glasgow Coma Scale (GCS) score and CT score combined with serum S100B protein level for evaluation of injury severity and predicting early prognosis of acute traumatic brain injury (TBI).

OBJECTIVE

A total of 108 patients with TBI admitted within 24 h after injury in the Emergency Department of West China Hospital from May, 2019 to May, 2020 were enrolled in this study. The clinical data, laboratory test results, CT examination, GCS score, Full Outline of Unresponsiveness score, Fisher CT classification, Rotterdam CT score, and serum S100B protein level of the patients were collected upon admission. The patients were followed up for 28 days and divided based on their Glasgow Outcome Scale (GOS) scores into poor prognosis group (GOS 1-3) and good prognosis group (GOS 4-5). The indexes related to poor prognosis were analyzed for their efficacy for predicting the patinets' prognosis. According to the results of head CT, the patients were divided into CT^- positive (CT⁺) group and CT^- negative (CT^-) group, and the efficacy of serum S100B protein level for predicting CT positivity was evaluated.

OBJECTIVE

Compared with those with favorable prognosis, the patients with poor prognosis had significantly lower GCS scores (P < 0.01) and higher Rotterdam CT score and serum S100B protein levels (P < 0.01). Among the 3 index, serum S100B protein level had the highest AUC value (0.79); among the combined indexes, GCS score combined with serum S100B protein had the highest AUC value (0.80). Serum S100B protein level was significantly higher in CT⁺ group than in CT - group (P < 0.05) with a significant correlation with Rotterdam CT score (r=0.26, P < 0.01).

OBJECTIVE

Serum S100B protein level, GCS score, and Rotterdam CT score can be used as indicators for evaluating the severity of acute TBI, and they are all closely related with early prognosis of the patients. The combination of serum S100B protein, GCS score and Rotterdam CT score has better performance than any of the 3 indexes alone for predicting early prognosis of the patients. Serum S100B protein level is correlated with head imaging findings of patients with acute TBI, but its value in selection of appropriate imaging modalities awaits further investigation.

Early risk stratification after resuscitation from cardiac arrest

Emergency clinicians often resuscitate cardiac arrest patients, and after acute resuscitation, clinicians face multiple decisions regarding disposition. Recent evidence suggests that out-of-hospital cardiac arrest patients with return of spontaneous circulation have higher odds of survival to hospital discharge, long-term survival, and improved functional outcomes when treated at centers that can provide advanced multidisciplinary care. For community clinicians, a high volume cardiac arrest center may be hours away. While current guidelines recommend against neurological prognostication in the first hours or days after return of spontaneous circulation, there are early findings suggestive of irrecoverable brain injury in which the patient would receive no benefit from transfer. In this Concepts article, we describe a simplified approach to quickly evaluate neurological status in cardiac arrest patients and identify findings concerning for irrecoverable brain injury. Characteristics of the arrest and resuscitation, initial neurological assessment, and brain computed tomography together can identify patients with high likelihood of irrecoverable anoxic injury. Patients who may benefit from centers with access to continuous electroencephalography are discussed. This approach can be used to identify patients who may benefit from rapid transfer to cardiac arrest centers versus those who may benefit from care close to home. Risk stratification also can provide realistic expectations for recovery to families.

Brain injury after cardiac arrest: from prognostication of comatose patients to rehabilitation

More patients are surviving cardiac arrest than ever before; however, the burden now lies with estimating neurological prognoses in a large number of patients who were initially comatose, in whom the ultimate outcome is unclear. Neurologists, neurointensivists, and clinical neurophysiologists must accurately balance the concern that overly conservative prognostication could leave patients in a severely disabled state, with the possibility that inaccurately pessimistic prognostication could lead to the withdrawal of life-sustaining treatment in patients who might otherwise have a good functional outcome. Prognostic tools have improved greatly, including electrophysiological tests, neuroimaging, and chemical biomarkers. Conclusions about the prognosis should be delayed at least 72 h after arrest to allow for the clearance of sedative drugs. Cognitive impairments, emotional problems, and fatigue are common among patients who have survived cardiac arrest, and often go unrecognised despite being related to caregiver burden and a decreased participation in society. Through simple screening, these problems can be identified, and patients can be provided with adequate information and rehabilitation.

Automated pupillometry and the FOUR score - what is the diagnostic benefit in neurointensive care?

Introduction

The Glasgow Coma Scale (GCS) and visual inspection of pupillary function are routine measures to monitor patients with impaired consciousness and predict their outcome in the neurointensive care unit (neuro-ICU). Our aim was to compare more recent measures, i.e. FOUR score and automated pupillometry, to standard monitoring with the GCS and visual inspection of pupils.

Methods

Supervised trained nursing staff examined a consecutive sample of patients admitted to the neuro-ICU of a tertiary referral centre using GCS and FOUR score and assessing pupillary function first by visual inspection and then by automated pupillometry. Clinical outcome was evaluated 6 months after admission using the Glasgow Outcome Scale-Extended.

Results

Fifty-six consecutive patients (median age 63 years) were assessed a total of 234 times. Of the 36 patients with at least one GCS score of 3, 13 had a favourable outcome. All seven patients with at least one FOUR score of ≤ 3 had an unfavourable outcome, which was best predicted by a low “brainstem” sub-score. Compared to automated pupillometry, visual assessment underestimated pupillary diameters (median difference, 0.4 mm; P = 0.006). Automated pupillometry detected a preserved pupillary light reflex in 10 patients, in whom visual inspection had missed pupillary constriction.

Discussion

Training of nursing staff to implement frequent monitoring of patients in the neuro-ICU with FOUR score and automated pupillometry is feasible. Both measures provide additional clinical information compared to the GCS and visual assessment of pupillary function, most importantly a more granular classification of patients with low levels of consciousness by the FOUR score.

Resting-State NIRS-EEG in Unresponsive Patients with Acute Brain Injury: A Proof-of-Concept Study

BACKGROUND

Neurovascular-based imaging techniques such as functional MRI (fMRI) may reveal signs of consciousness in clinically unresponsive patients but are often subject to logistical challenges in the intensive care unit (ICU). Near-infrared spectroscopy (NIRS) is another neurovascular imaging technique but low cost, can be performed serially at the bedside, and may be combined with electroencephalography (EEG), which are important advantages compared to fMRI. Combined NIRS-EEG, however, has never been evaluated for the assessment of neurovascular coupling and consciousness in acute brain injury.

METHODS

We explored resting-state oscillations in eight-channel NIRS oxyhemoglobin and eight-channel EEG band-power signals to assess neurovascular coupling, the prerequisite for neurovascular-based imaging detection of consciousness, in patients with acute brain injury in the ICU (n = 9). Conscious neurological patients from step-down units and wards served as controls (n = 14). Unsupervised adaptive mixture-independent component analysis (AMICA) was used to correlate NIRS-EEG data with levels of consciousness and clinical outcome.

RESULTS

Neurovascular coupling between NIRS oxyhemoglobin (0.07-0.13 Hz) and EEG band-power (1-12 Hz) signals at frontal areas was sensitive and prognostic to changing consciousness levels. AMICA revealed a mixture of five models from EEG data, with the relative probabilities of these models reflecting levels of consciousness over multiple days, although the accuracy was less than 85%. However, when combined with two channels of bilateral frontal neurovascular coupling, weighted k-nearest neighbor classification of AMICA probabilities distinguished unresponsive patients from conscious controls with > 90% accuracy (positive predictive value 93%, false discovery rate 7%) and, additionally, identified patients who subsequently failed to recover consciousness with > 99% accuracy.

DISCUSSION

We suggest that NIRS-EEG for monitoring of acute brain injury in the ICU is worthy of further exploration. Normalization of neurovascular coupling may herald recovery of consciousness after acute brain injury.

Sudden unresponsive patient with normal vital signs: what is going on?

PURPOSE OF REVIEW

To summarize the differential diagnosis and diagnostic approach of sudden unresponsiveness with normal vital signs in various settings, including the ICU.

RECENT FINDINGS

Sudden unresponsiveness may be either transient or persistent, and may result from primary brain diseases or nonstructural systemic conditions. Life-threatening causes should always be discriminated from those more benign. Regional epidemiology, for example regarding intoxications, and evolving therapeutic management, for example for ischemic stroke, should always be taken into account for optimal opportunity for rapid diagnosis and best management.

SUMMARY

Sudden unresponsiveness with normal vital signs should trigger immediate and focused diagnostic evaluation to find or exclude those conditions requiring urgent, and possibly life-saving, management.

Diagnostic Reliability of Headset-Type Continuous Video EEG Monitoring for Detection of ICU Patterns and NCSE in Patients with Altered Mental Status with Unknown Etiology

BACKGROUND/OBJECTIVE

Simplified continuous electroencephalogram (cEEG) monitoring has shown improvement in detecting seizures; however, it is insufficient in detecting abnormal EEG patterns, such as periodic discharges (PDs), rhythmic delta activity (RDA), spikes and waves (SW), and continuous slow wave (CS), as well as nonconvulsive status epilepticus (NCSE). Headset-type continuous video EEG monitoring (HS-cv EEG monitoring; AE-120A EEG Headset™, Nihon Kohden, Tokyo, Japan) is a recently developed easy-to-use technology with eight channels. However, its ability to detect abnormal EEG patterns with raw EEG data has not been comprehensively evaluated. We aimed to examine the diagnostic accuracy of HS-cv EEG monitoring in detecting abnormal EEG patterns and NCSE in patients with altered mental status (AMS) with unknown etiology. We also evaluated the time required to initiate HS-cv EEG monitoring in these patients.

METHODS

We prospectively observed and retrospectively examined patients who were admitted with AMS between January and December 2017 at the neurointensive care unit at Asakadai Central General Hospital, Saitama, Japan. We excluded patients whose data were missing for various reasons, such as difficulties in recording, and those whose consciousness had recovered between HS-cv EEG and conventional cEEG (C-cEEG) monitoring. For the included patients, we performed HS-cv EEG monitoring followed by C-cEEG monitoring. Definitive diagnosis was confirmed by C-cEEG monitoring with the international 10-20 system. As the primary outcome, we verified the sensitivity and specificity of HS-cv EEG monitoring in detecting abnormal EEG patterns including PDs, RDA, SW, and CS, in detecting the presence of PDs, and in detecting NCSE. As the secondary outcome, we calculated the time to initiate HS-cv EEG monitoring after making the decision.

RESULTS

Fifty patients (76.9%) were included in the final analyses. The median age was 72 years, and 66% of the patients were male. The sensitivity and specificity of HS-cv EEG monitoring for detecting abnormal EEG patterns were 0.974 (0.865-0.999) and 0.909 (0.587-0.998), respectively, and for detecting PDs were 0.824 (0.566-0.926) and 0.970 (0.842-0.999), respectively. We diagnosed 13 (26%) patients with NCSE using HS-cv EEG monitoring and could detect NCSE with a sensitivity and specificity of 0.706 (0.440-0.897) and 0.970 (0.842-0.999), respectively. The median time needed to initiate HS-cv EEG was 57 min (5-142).

CONCLUSIONS

HS-cv EEG monitoring is highly reliable in detecting abnormal EEG patterns, with moderate reliability for PDs and NCSE, and rapidly initiates cEEG monitoring in patients with AMS with unknown etiology.

The current significance of the FOUR score: A systematic review and critical analysis of the literature

BACKGROUND

The Full Outline of Un-Responsiveness Score (FOURs) is a scale for clinical assessment of consciousness that was introduced to overcome disadvantages of the widely accepted Glasgow Coma Scale (GCS).

OBJECTIVE

To carry out a systematic review and critical analysis of the available literature on the clinical application of FOURs and perform a comparison to GCS, in terms of reliability and predictive value.

METHODS

Initial search retrieved a total of 147 papers. After applying strict inclusion criteria and further article selection to overcome data heterogeneity, a statistical comparison of inter-rater reliability, in-hospital mortality and long-term outcome prediction between the two scales in the adult and pediatric population was done.

RESULTS

Even though FOURs is more complicated than GCS, its application remains quite simple. Its reliability, validity and predictive value have been supported by an increasing number of studies, especially in critical care. A statistically significant difference (p = .034) in predicting in-hospital mortality in adults, in favor of FOURs when compared to GCS, was found. However, whether it poses a clinically significant advantage in detecting patients' deterioration and outcome prediction, compared to other scaling systems, remains unclear.

CONCLUSIONS

Further studies are needed to discern the FOURs' clinical usefulness, especially in patients in non-critical condition, with milder disorders of consciousness.