Prognosis Of Coma Research Articles

Prognosis of comatose patients with reduced EEG montage by combining quantitative EEG features in various domains.

As the frontoparietal network underlies recovery from coma, a limited frontoparietal montage was used, and the prognostic values of EEG features for comatose patients were assessed. Collected with a limited frontoparietal EEG montage, continuous EEG recordings of 81 comatose patients in ICU were used retrospectively. By the 60-day Glasgow outcome scale (GOS), the patients were dichotomized into favorable and unfavorable outcome groups. Temporal-, frequency-, and spatial-domain features were automatically extracted for comparison. Partial correlation analysis was applied to eliminate redundant factors, and multiple correspondence analysis was used to explore discrimination between groups. Prognostic characteristics were calculated to assess the performance of EEG feature-based predictors established by logistic regression. Analyses were performed on all-patients group, strokes subgroup, and traumatic brain injury (TBI) subgroup. By analysis of all patients, raised burst suppression ratio (BSR), suppressed root mean square (RMS), raised power ratio of β to α rhythm (β/α), and suppressed phase-lag index between F3 and P4 (PLI [F3, P4]) were associated with unfavorable outcome, and yielded AUC of 0.790, 0.811, 0.722, and 0.844, respectively. For the strokes subgroup, the significant variables were BSR, RMS, θ/total, θ/δ, and PLI (F3, P4), while for the TBI subgroup, only PLI (F3, P4) was significant. BSR combined with PLI (F3, P4) gave the best predictor by cross-validation analysis in the all-patients group (AUC = 0.889, 95% CI: 0.819-0.960). Features extracted from limited frontoparietal montage EEG served as valuable coma prognostic tools, where PLI (F3, P4) was always significant. Combining PLI (F3, P4) with features in other domains may achieve better performance. A limited-montage EEG coupled with an automated algorithm is valuable for coma prognosis.

Functional PET Neuroimaging in Consciousness Evaluation: Study Protocol.

Ensuring a robust and reliable evaluation of coma deepness and prognostication of neurological outcome is challenging. We propose to develop PET neuroimaging as a new diagnostic and prognosis tool for comatose patients using a recently published methodology to perform functional PET (fPET). This exam permits the quantification of task-specific changes in neuronal metabolism in a single session. The aim of this protocol is to determine whether task-specific changes in glucose metabolism during the acute phase of coma are able to predict recovery at 18 months. Participation will be proposed for all patients coming for a standard PET-CT in our center in order to evaluate global cerebral metabolism during the comatose state. Legally appointed representative consent will be obtained to slightly modify the exam protocol: (1) 18F-fluorodeoxyglucose (18F-FDG) bolus plus continuous infusion instead of a simple bolus and (2) more time under camera to perform dynamic acquisition. Participants will undergo a 55-min fPET session with a 20% bolus + 80% infusion protocol. Two occurrences of three block (5-min rest, 10-min auditory stimulation and 10-min emotional auditory stimulation) will be performed after reaching equilibrium of FDG arterial concentration. We will compare the regional brain metabolism at rest and during the sessions of auditory and emotional auditory stimulation to search for a determinant of coma recovery (18 months of follow-up after the exam). Emotional auditory stimulation should induce an activation of: the auditory cortex, the consciousness areas and the neural circuitry for emotion (function to coma deepness). An activation analysis will be carried out to highlight regional brain activation using dedicated custom-made software based on Python statistical and image processing toolboxes. The association between activation levels and the Coma Recovery Scale-Revisited (CRS-R) will be assessed using multivariate analysis. If successful, the results from this study will help improve coma prognosis evaluation based on the pattern of neuronal metabolism at the onset of the pathology. The study protocol, rationale and methods are described in this paper.

Human-in-the-Loop Predictive Analytics Using Statistical Learning.

The human-in-the-loop cyber-physical system provides numerous solutions for the challenges faced by the doctors or medical practitioners. There is a linear trend of advancement and automation in the medical field for the early diagnosis of several diseases. One of the critical and challenging diseases in the medical field is coma. In the medical research field, currently, the prediction of these diseases is performed only using the data gathered from the devices only; however, the human's input is much essential to accurately understand their health condition to take appropriate decision on time. Therefore, we have proposed a healthcare framework involving the concept of artificial intelligence in the human-in- the-loop cyber-physical system. This model works via a response loop in which the human's intention is concluded by gathering biological signals and context data, and then, the decision is interpreted to a system action that is recognizable to the human in the physical environment, thereby completing the loop. In this paper, we have designed a model for early prognosis of coma using the electroencephalogram dataset. In the proposed approach, we have achieved the best results using a statistical learning algorithm called autoregressive integrated moving average in comparison to artificial neural networks and long short-term memory models. In order to measure the efficiency of our model, we have used the root mean squared error (RMSE), mean absolute error (MAE), and mean squared error (MSE) value to evaluate the linear models as it gives the difference between the measured value and true or correct value. We have achieved the least possible error value for our dataset. To conduct this experiment, we used the dataset available in the phsyionet opensource community.

Predictive Value and Correlation of Neuron-Specific Enolase for Prognosis in Patients with Coma: A Systematic Review and Meta-Analysis

Objective: Coma is the most serious disturbance of consciousness, which affects the life quality of patients and increases the burden of their family. Studies to assess the prognostic value of neuron-specific enolase (NSE) in patients with coma have not led to precise, generally accepted prognostic rules. The study aims to assess the correlation between NSE and prognosis of coma and the predictive value of NSE for clinical prognosis. Methods: A search was conducted using PubMed, Web of Science, EMBASE, Cochrane Library, China National Knowledge Infrastructure (CNKI), and WanFang Data from the establishment time of databases to December 2019. This analysis included patients with coma, regardless of how long the coma was. In total, 26 articles were retrieved and included in the review. Results: The meta-analysis revealed the NSE concentration of patients with coma is significantly higher than that of the control group (standard mean difference = 0.88, 95% confidence interval [CI]: 0.63–1.12, p < 0.05). The pooled sensitivity and specificity of NSE in coma diagnosis was 0.5 (95% CI: 0.39–0.61) and 0.86 (95% CI: 0.71–0.94). Conclusions: The NSE concentration of patients with poor coma prognosis is significantly higher than that of the control group. The high NSE concentration is not necessarily a poor prognosis for coma, but low NSE concentration indicates a high probability of a good prognosis for coma.

Finally, Some Neurophysiologic Good News-Favorable Prognosis in Coma.

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Development of a point of care system for automated coma prognosis: a prospective cohort study protocol

IntroductionComa is a deep state of unconsciousness that can be caused by a variety of clinical conditions. Traditional tests for coma outcome prediction are based mainly on a set of...

Coma in Thyroid Storm: Review of Aggregated English-Language Case Reports.

ContextComa is a serious manifestation of thyroid storm (TS) about which little is known.ObjectiveTo describe the features, duration, treatment response, and prognosis of coma in the setting of TS.DesignAggregate analysis of individual English-language case reports of coma in the setting of TS from 1935 to January 2019.SettingHospitals.PatientsSixty-five cases were identified, 29 from case reports and 36 from case series.InterventionsAntithyroid drugs, corticosteroids, beta-blockers, iodine, intubation, plasmapheresis, antibiotics, thyroidectomy, radioiodine, dialysis, and l-carnitine.Main Outcome MeasuresAwakening and death rates overall and in relation to administered treatments, day of coma presentation, and time from coma onset; symptoms associated with coma; TS and coma scales; thyroid and cerebrospinal laboratory tests; electroencephalogram; brain imaging; and autopsy results.ResultsMortality was 38% in the setting of TS-related coma, 11% during the years 1978 to 2019 compared with 70% for 1935 to 1977. Both awakening and death commonly occurred within the first 2 days of coma onset. Reduction in total and free T4 values, and possibly also total T3 value, correlated with awakening from coma. Lower death rates were associated with use of antithyroid drugs, corticosteroids, beta-blockers, and intubation. Plasmapheresis was associated with awakening in 67% of cases but not with lower death rates.ConclusionsPrognosis of coma associated with TS remains poor. Current guidelines for the early use of plasmapheresis in unresolving TS are advocated and should be considered urgently at the point of confusion or delirium in an effort to abort coma.

The neuron specific enolase (NSE) ratio offers benefits over absolute value thresholds in post-cardiac arrest coma prognosis

IntroductionSerum neuron-specific enolase (NSE) levels have been shown to correlate with neurologic outcome in comatose survivors of cardiac arrest but use of absolute NSE thresholds is limited. This study describes and evaluates a novel approach to analyzing NSE, the NSE ratio, and evaluates the prognostic utility of NSE absolute value thresholds and trends over time. Methods100 consecutive adult comatose cardiac arrest survivors were prospectively enrolled. NSE levels were assessed at 24, 48, and 72 h post-arrest. Primary outcome was the Glasgow Outcome Score (GOS) at 6 months post-arrest; good outcome was defined as GOS 3–5. Absolute and relative NSE values (i.e. the NSE ratio), peak values, and the trend in NSE over 72 h were analyzed. Results98 patients were included. 42 (43%) had a good outcome. Five good outcome patients had peak NSE >33 µg/L (34.9–46.4 µg/L). NSE trends between 24 and 48 h differed between outcome groups (decrease by 3.0 µg/L (0.9–7.0 µg/L) vs. increase by 13.4 µg/L (−3.7 to 69.4 µg/L), good vs. poor, p = 0.004). The 48:24 h NSE ratio differed between the good and poor outcome groups (0.8 (0.6–0.9) vs. 1.4 (0.8–2.5), p = 0.001), and a 48:24 h ratio of ≥1.7 was 100% specific for poor outcome. ConclusionsThe NSE ratio is a unique method to quantify NSE changes over time. Values greater than 1.0 indicate increasing NSE and may be reflective of ongoing neuronal injury. The NSE ratio obviates the need for an absolute value cut-off.

The Burden of Clinical Neurophysiology for the Neurological Prognosis of Coma

The Burden of Clinical Neurophysiology for the Neurological Prognosis of Coma

The Nature of EEG Reactivity to Light, Sound, and Pain Stimulation in Neurosurgical Comatose Patients Evaluated by a Quantitative Method.

EEG reactivity (EEG-R) is regarded as an important parameter in coma prognosis but knowledge is sparse on the nature of EEG changes due to different kinds of stimulation and their prognostic significance. EEG-R was quantified in a study of 39 comatose neurosurgical patients. Six 30-second standardized visual, auditory, and painful stimulations were applied. EEG-R in the delta, theta, alpha, and beta band was normalized in z-scores as the power of a stimulation epoch relative to average power of 6 resting epochs. Outcome measure was 3 months Glasgow Outcome Scale. Increase in EEG activity was related to poor outcome, was more common (13.4% of tests), and grew continuously during the 30-second stimulation epoch. Decrease in EEG activity was related to good outcome, was rarer (2.5%), and peaked around 15 seconds. Pain was the most provocative stimulation (20.4%) followed by sound (8.7%) and eye-opening (6.7%). Discrimination between good (n = 6) and poor (n = 33) outcome was best in the theta and alpha bands for pain stimulation in the first 10-20 seconds and for sound stimulation in the first 5 to 10 seconds, eye-opening did not discriminate. Increase in activity predicted poor outcome with a high specificity 100% (CI = 52%-100%) and a modest sensitivity of 39% (CI = 23%-58%). Decrease in activity predicted good outcome with a high specificity of 100% (CI = 87%-100%) and a modest sensitivity of 33% (CI = 6%-76%). This quantitative study reveals new knowledge about the nature of EEG-R, which contribute to the development of more reliable and objective clinical procedures for outcome prediction.

Télétransmission en électroencéphalographie et problématique actuelle. SMART-EEG : une solution innovante

The electroencephalogram (EEG) is a test that allows recording of brain activity and is essential for diagnosis and prognosis of coma, monitoring of epilepsy and maturation of the central nervous system. Currently, the national shortage of neurophysiologist physicians no longer allows access to care for all. Currently, remote transmissions of EEG have been implemented in France; 34% of them are not computerized. After analyzing the problems faced by these “platforms”, we describe the SMART-EEG project aimed to provide technical solutions and innovative practices to the major concerns of the implementation and interpretation of EEG examinations via telemedicine in France.

Analysis of Prognostic Factors of Children with Intracranial Infection Coma

Objective: To investigate the prognostic factors of coma due to intracranial infection in children, in order to judge the prognosis of coma earlier and guide appropriate treatment. Methods: 1) Collecting the clinical data of 39 comatose children due to intracranial infection admitted into Department of Neurology in Children’s Hospital of Chongqing Medical University from July to September 2007 and 2009, and analyzing their age and sex distribution, causes of coma, and laboratory examinations retrospectively. 2) Implementing the Glasgow coma score among these children immediately after admission, and collecting the serum and cerebrospinal fluid within 24 - 48 hours, and then measuring the NSE levels. 3) Following up these children 3 months after discharge, and analyzing the relationships among prognosis and age, sex, etiology, protein content in CSF, and NSE levels in Serum and CSF. Results: 1) In the cases studied, the age range was from 9 months to 14 years, the average age was (4.25 ± 2.82) years, and 9 months - 3 years, 3 - 5 years, 5 - 11 years, and ≥11 years were accounted for 33.3%, 30.8%, 30.8%, 5.1% respectively. There were 24 males and 15 females, and the gender ratio (male-to-female) was 1.6:1. 2) The group of 39 patients consists of Japanese encephalitis (23 cases, 59%), Viral encephalitis (5 cases, 12.8%), Tuberculous meningitis (5 cases, 12.8%), Acute disseminated encephalomyelitis (5 cases, 12.8%) and Purulent meningitis (1 cases, 2.6%). 3) CSF examination in 33 cases, protein elevated in 18 cases (54.5%), content between 0.47 and 4.33 g/L. 4) The statistical analysis showed that the causes, CSF protein content, serum and cerebrospinal fluid NSE levels were correlated with the prognosis, and that the age and sex had no correlation with the prognosis. Conclusions: 1) In this group of 39 patients, the incidence of children under 5 years old was the highest, and the incidence of boys was higher than girls. 2) Infectious diseases were the most common cause of coma in children. 3) Cerebrospinal fluid protein content was correlated with the prognosis, and the prognosis was worse as the protein content was higher. 4) NSE was a specific biochemical parameter of pathological damage nerve tissue; serum NSE levels could indirectly reflect the changes in CSF.

Prognosis of Coma After Cardiac Arrest in the Era of Hypothermia

Outcome prediction is more difficult in comatose survivors of cardiac arrest who are treated with hypothermia than in those who are kept normothermic. This article compares prognostication measures in these two groups of patients. The introduction of therapeutic hypothermia for cardiac arrest has resulted in reduced mortality and better neurologic outcomes among survivors. However, it has also introduced greater uncertainty into the process of prognostication. For guidance on predicting outcome, most neurologists have relied on the 2006 AAN practice parameter. The studies on which the practice parameter was based, however, were performed before the advent of hypothermia. Data from posthypothermia era studies suggest a change in the predictive power of some markers that are regularly used to assess prognosis in post-cardiac arrest patients. It is unclear whether the same rules apply when predicting outcomes after cardiac arrest in cooled patients. In this new era of hypothermia, caution must be exercised when using the current AAN practice parameter to predict prognosis in post-cardiac arrest comatose survivors. This article compares and contrasts prognostication before and after the introduction of hypothermia in an attempt to provide new guidance on predicting outcomes.

Prognosis of coma after therapeutic hypothermia: A prospective cohort study

This study was designed to establish the reliability of neurologic examination, neuron-specific enolase (NSE), and median nerve somatosensory-evoked potentials (SEPs) to predict poor outcome in patients treated with mild hypothermia after cardiopulmonary resuscitation (CPR). This multicenter prospective cohort study included adult comatose patients admitted to the intensive care unit (ICU) after CPR and treated with hypothermia (32-34°C). False-positive rates (FPRs 1 - specificity) with their 95% confidence intervals (CIs) were calculated for pupillary light responses, corneal reflexes, and motor scores 72 hours after CPR; NSE levels at admission, 12 hours after reaching target temperature, and 36 hours and 48 hours after collapse; and SEPs during hypothermia and after rewarming. The primary outcome was poor outcome, defined as death, vegetative state, or severe disability (Glasgow Outcome Scale 1-3) after 6 months. Of 391 patients included, 53% had a poor outcome. Absent pupillary light responses (FPR 1; 95% CI, 0-7) or absent corneal reflexes (FPR 4; 95% CI, 1-13) 72 hours after CPR, and absent SEPs during hypothermia (FPR 3; 95% CI, 1-7) and after rewarming (FPR 0; 95% CI, 0-18) were reliable predictors. Motor scores 72 hours after CPR (FPR 10; 95% CI, 6-16) and NSE levels were not. In patients with persisting coma after CPR and therapeutic hypothermia, use of motor score or NSE, as recommended in current guidelines, could possibly lead to inappropriate withdrawal of treatment. Poor outcomes can reliably be predicted by testing brainstem reflexes 72 hours after CPR and performing SEP.

Glasgow Coma Scale, Brain Computerized Tomography and Neurophysiological Methods as Prognostic Factors of Pediatric Coma

Background and objectives: Coma is characterized by the total absence of both arousal and awareness. The outcome of coma depends on the etiology, depth and duration of impaired consciousness. It is likely that brain electrical function monitoring will play an increasingly important role in evaluating prognosis of coma in children. Aim: To compare the predictive values of clinical examinations combined with the recordings of Electroencephalography (EEG) and Brainstem Auditory-Evoked Potentials (BAEP) and computed tomography (CT) of the brain in the evaluation of coma outcome in children. Methods: Twenty children with coma aged 3-14 years were included in the study and subjected to: full history, clinical, neurological and otological examination. Medical investigations for coma, EEG, CT brain and auditory brainstem evoked potential (BAEP) measurements were performed for all patients. They were subdivided into 2 groups: group 1 included 8 patients with surgical causes of coma, group 2 include 12 patients with medical causes of coma. Results: There was younger age, lower Glasgow Coma Scale (GCS) and more significant incidence of unfavourable outcome (death, disability) in patients of surgical coma (group 1). A significant difference between both groups was observed regarding the presence of brain edema and intracranial hemorrhage (100% in group 1) while normally visualized basal cisterns were significantly more in group (2) (p=0.02). Favourable outcome was strongly related to normally visualize basal cisterns in CT brain (p=0.002), normal/ borderline EEG activity (p=0.03) and normal BAEP waves (p=0.009). Disability was significantly related to slow activity waves (p=0.015) and diffuse high voltage EEG discharges (0.009). While mortality was significantly related to the presence of intracranial bleeding in CT brain (p=0.02), silence EEG waves (p=0.005) and absent BAEP waves (0.012). Conclusion: EEG and Auditory brainstem response are valuable as prognostic predictors of pediatric coma either due to medical or surgical causes. The Glasgow Coma Scale (GCS) has several important limitations as a predictor of survival in the general critically ill population while CT brain is mostly important for diagnostic rather than prognostic factor in comatosed children.

P11.2 Joint use of short-and long-latency evoked potentials and EEG reactivity for coma prognosis in a non-university hospital

P11.2 Joint use of short-and long-latency evoked potentials and EEG reactivity for coma prognosis in a non-university hospital

Auditory event-related potentials as indicators of good prognosis in coma of non-anoxic etiology

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EVALUATION AND PROGNOSIS OF COMA

ABSTRACT Evaluation of coma in the intensive care unit can be a very common and complicated consultation for the neurologist. Unlike other consultations, the neurologist often is asked to counsel the family in addition to providing an opinion on the prognosis of the patient. As an aid to this difficult challenge, this chapter will discuss the definition of coma, two approaches to the evaluation of coma, and strategies to determine the prognosis of a patient with coma. In addition, the chapter will discuss recent research in the nature of the vegetative state, which is one of the major outcomes of coma. Ultimately, the decisions that are made by families with their physicians about withdrawing or continuing life-preserving care for patients rest in the understanding of the likely prognosis of the patient. Well-informed discussions are becoming increasingly difficult as our understanding of cognitive function in coma and vegetative state evolves.

Assessment and management of the patient with impaired consciousness

Abstract Coma and impaired consciousness are frequent medical emergencies. Assessment of such patients requires a working knowledge of the neuro-anatomical basis of consciousness. Consciousness is dependent upon the integrity of two structures: the reticular activating system in the brainstem, which governs the level of arousal, and the cerebral cortex of both hemispheres, which determines the content of consciousness. Coma can result either from pathological processes in the brainstem or from diffuse pathology in the cerebral cortex. The Glasgow Coma Score (GCS) is invaluable for documenting the level of coma and monitoring for clinical change, but is of no diagnostic significance. A thorough neurological assessment should allow separation of patients into three separate groups: high likelihood of structural supra- or infratentorial pathology requiring urgent CT brain scans (e.g. cerebrovascular disease); coma with meningeal irritation where lumbar puncture and prompt antibiotic therapy may be life-saving (e.g. bacterial meningitis); and patients with no focal signs or meningeal irritation where metabolic and toxic causes are common (e.g. drug overdose, hypoglycaemia, hyponatraemia and liver failure). The prognosis of coma depends on aetiology, depth and duration of coma and presence of brainstem reflexes.

Evoked potentials in the ICU

The most informative neurophysiological techniques available in the neurosurgical intensive care unit are electroencephalograph and somatosensory evoked potentials. Such tools, which give an evaluation of cerebral function in comatose patients, support clinical evaluation and are complementary to neuroimaging. They serve both diagnostic/prognostic and monitoring purposes. While for the former, discontinuous monitoring is sufficient, for the latter, to obtain increased clinical impact, continuous monitoring is necessary. To perform and interpret these examinations in the neurosurgical intensive care unit, both the technician and the neurophysiologist need specific training in the intensive care field. There is sufficient evidence to show that somatosensory evoked potentials are the best single indicator of early prognosis in traumatic and hypoxic-ischaemic coma compared to the Glasgow Coma Score, computed tomography scan and electroencephalograph. Indeed, somatosensory evoked potentials should always be combined with clinical examination to determine the prognosis of coma. Despite widespread use of somatosensory evoked potentials and their prognostic utility in acute brain injury, few studies exist on continuous somatosensory evoked potential monitoring in the intensive care unit. We carried out a pilot study of continuous electroencephalograph-somatosensory evoked potential monitoring in the neurosurgical intensive care unit (traumatic brain injury and intracranial haemorrhage, Glasgow Coma Score <9, intracranial pressure monitoring). All patients stable from a clinical and computed tomography scan point of view showed no significant somatosensory evoked potential modifications, while in the case of clinical deterioration (23%), somatosensory evoked potentials always showed significant modifications. While somatosensory evoked potentials correlated with short-term outcome, intracranial pressure showed a poor correlation. We believe neurophysiological monitoring is an ideal complement to the other parameters monitored in the neurosurgical intensive care unit. Whereas intracranial pressure is simply a pressure index, electroencephalograph-somatosensory evoked potential monitoring reflects to what extent cerebral parenchyma still remains metabolically active during acute brain injury.