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

Managing hemolysis in serum neuron-specific enolase measurements - an automated algorithm for routine practice

Neuron-specific enolase (NSE) derived from neurons and peripheral neuroendocrine cells is a biomarker for neuroendocrine tumors and for prognostication in comatose cardiac arrest survivors. However, as platelets and erythrocytes contain NSE, hemolysis causes falsely elevated NSE. We used native serum and hemolysate derived from the same patients to make serial dilutions, and subsequently measured NSE (mNSE) and hemolytic index (HI) in each dilution. An algorithm suitable for the laboratory information system was developed based on the mNSE, HI and the estimated gradient of hemolytic interference from 30 patients. We estimated the associated uncertainty of the corrected NSE (cNSE) results based on the observed range of the gradient and derived an equation for cNSE for samples with limited hemolysis (i.e. 5 < HI ≤ 30): cNSE = mNSE - HI × (0.34 ± 0.23) µg/L. By semi-quantitatively grading the contribution from limited hemolysis, a texted result noting the hemolysis-associated degree of uncertainty can accompany the cNSE result. The major challenge of hemolysis when using serum NSE as a biomarker can be managed using an automated algorithm for correction of NSE results based on degree of hemolysis. However, laboratorians and clinicians should be aware of the limitations associated with in vivo hemolysis.

Predictive Performance of Neuron-Specific Enolase (NSE) for Survival after Resuscitation from Cardiac Arrest: A Systematic Review and Meta-Analysis

The prediction of outcomes following cardiac arrest continues to provide significant difficulties. A preferred strategy involves adopting a multimodal approach, which encompasses the careful evaluation of the biomarker neuron-specific enolase (NSE). This systematic review and meta-analysis aimed to gather and summarize new and existing evidence on the prediction effect of neuron-specific enolase for survival to hospital discharge among adult patients with cardiac arrest. We searched PubMed Central, Scopus, EMBASE databases, and the Cochrane Library without language restrictions from their inceptions until 30 October 2023 and checked the reference lists of the included studies. Pooled results were reported as standardized mean differences (SMDs) and were presented with corresponding 95% confidence intervals (CIs). The primary outcome was survival to hospital discharge (SHD). Eighty-six articles with 10,845 participants were included. NSE showed a notable degree of specificity in its ability to predict mortality as well as neurological status among individuals who experienced cardiac arrest (p < 0.05). This study demonstrates the ability to predict fatality rates and neurological outcomes, both during the time of admission and at various time intervals after cardiac arrest. The use of NSE in a multimodal neuroprognostication algorithm has promise in improving the accuracy of prognoses for persons who have undergone cardiac arrest.

The use of neurone specific enolase to prognosticate neurological recovery and long term neurological outcomes in OOHCA patients

Introduction

Hypoxic-ischaemic brain injury (HIBI), is a common sequalae following out-of-hospital cardiac arrest (OOHCA), it is reported as the cause of death in 68% of patients who survive to ICU admission, while other patients can be left with permanent neurological disability. Prediction of neurological outcome follows a multimodal approach, including use of the biomarker, neurone specific enolase (NSE). There is however no definitive cut-off value for poor neurological outcome, and little research has analysed NSE and long-term outcomes in survivors. We investigated an NSE threshold for poor short-term neurological outcome and the relationship between NSE and poor neurological outcome in survivors.

Methods

A retrospective study was conducted of all adult OOHCA patients admitted to the Royal County Sussex Hospital ICU between April 2017 and November 2018. NSE levels, Targeted Temperature Management (TTM), cross-sectional imaging, mortality and GCS on ICU discharge were recorded. Assessment of neurological function after a median of 19 months (range 14-32 months) post ICU discharge was undertaken following ICU discharge and related to NSE.

Results

NSE levels were measured in 59 patients; of these 36 (61%) had a poor neurological outcome due to hypoxic ischaemic brain injury. Youden's index and ROC analysis established an NSE cut-off value of 64.5 μg/L, with AUC of 0.901, sensitivity of 77.8% and specificity of 100%. Follow-up of 26 survivors after 19 months did not show a significant relationship between NSE after OOHCA and long-term neurological outcome.

Conclusion

Our results show that NSE >64.5 µg/L has a poor short-term neurological outcome with 100% specificity. Whilst limited by a low sample size, NSE in survivors showed no relationship with neurological outcome post OOHCA in the long term.

Confounders for prognostic accuracy of neuron-specific enolase after cardiac arrest: A retrospective cohort study

AIM

To evaluate neuron-specific enolase (NSE) thresholds for prediction of neurological outcome after cardiac arrest and to analyze the influence of hemolysis and confounders.

METHODS

Retrospective analysis from a cardiac arrest registry. Determination of NSE serum concentration and hemolysis-index (h-index) 48-96 hours after cardiac arrest. Evaluation of neurological outcome using the Cerebral Performance Category score (CPC) at hospital discharge. Separate analyses considering CPC 1-3 and CPC 1-2 as good neurological outcome. Analysis of specificity and sensitivity for poor and good neurological outcome prediction with and without exclusion of hemolytic samples (h-index larger than 50).

RESULTS

Among 356 survivors three days after cardiac arrest, hemolysis was detected in 28 samples (7.9%). At a threshold of 60 µg/L, NSE predicted poor neurological outcome (CPC 4-5) in all samples with a specificity of 92% (86-95%) and sensitivity of 73% (66-79%). In non-hemolytic samples, specificity was 94% (89-97%) and sensitivity 70% (62-76%). At a threshold of 100 µg/L, specificity was 98% (95-100%, all samples) and 99% (95-100%, non-hemolytic samples), and sensitivity 58% (51-65%) and 55% (47-63%), respectively. Possible confounders for elevated NSE in patients with good neurological outcome were ECMO, malignancies, blood transfusions and acute brain diseases. Nine patients with NSE below 17 µg/L had CPC 5, all had plausible death causes other than hypoxic-ischemic encephalopathy.

CONCLUSIONS

NSE concentrations higher than 100 µg/L predicted poor neurological outcome with high specificity. An NSE less than 17 µg/L indicated absence of severe hypoxic-ischemic encephalopathy. Hemolysis and other confounders need to be considered.

INSTITUTIONAL PROTOCOL NUMBER

The local ethics committee (board name: Ethikkommission der Charité) approved this study by the number: EA2/066/23, approval date: 28th June 2023, study title "'ROSC' - Resuscitation Outcome Study."

Association between Neuron-Specific Enolase, Memory Function, and Postoperative Delirium after Transfemoral Aortic Valve Replacement

INTRODUCTION

Although transfemoral aortic valve replacement (TAVR) is a safe treatment for elderly patients with severe aortic valve stenosis, postoperative microembolism has been described. In this secondary endpoint analysis of the POST-TAVR trial, we aimed to investigate whether changes in neuron-specific enolase (NSE)-a biomarker of neuronal damage-are associated with changes in memory function or postoperative delirium (POD).

MATERIALS AND METHODS

This was a prospective single-center study enrolling patients undergoing elective TAVR. Serum NSE was measured before and 24 h after TAVR. POD was diagnosed using CAM-ICU testing. Memory function was assessed before TAVR and before hospital discharge using the "Consortium to Establish a Registry for Alzheimer's Disease" (CERAD) word list and the digit span task (DST) implemented in "∆elta-App".

RESULTS

Subjects' median age was 82 years (25th to 75th percentile: 77.5-85.0), 42.6% of subjects were women. CERAD scores significantly increased from pre- to post-TAVR, with p < 0.001. POD occurred in 4.4% (6/135) of subjects at median 2 days after TAVR. After TAVR, NSE increased from a median of 1.85 ng/mL (1.30-2.53) to 2.37 ng/mL (1.69-3.07), p < 0.001. The median increase in NSE was 40.4% (13.1-138.0) in patients with POD versus 17.3% (3.3-43.4) in those without POD (p = 0.17).

CONCLUSIONS

Memory function improved after TAVR, likely due to learning effects, with no association to change in NSE. Patients with POD appear to have significantly higher postoperative levels of NSE compared to patients without POD after TAVR. This finding suggests that neuronal damage, as indicated by NSE elevation, may not significantly impair assessed memory function after TAVR.

Factors Associated with Early Withdrawal of Life-Sustaining Treatments After Out-of-Hospital Cardiac Arrest: A Subanalysis of a Randomized Trial of Prehospital Therapeutic Hypothermia

BACKGROUND

The objective of this study is to describe incidence and factors associated with early withdrawal of life-sustaining therapies based on presumed poor neurologic prognosis (WLST-N) and practices around multimodal prognostication after out-of-hospital cardiac arrest (OHCA).

METHODS

We performed a subanalysis of a randomized controlled trial assessing prehospital therapeutic hypothermia in adult patients admitted to nine hospitals in King County with nontraumatic OHCA between 2007 and 2012. Patients who underwent tracheal intubation and were unconscious following return of spontaneous circulation were included. Our outcomes were (1) incidence of early WLST-N (WLST-N within < 72 h from return of spontaneous circulation), (2) factors associated with early WLST-N compared with patients who remained comatose at 72 h without WLST-N, (3) institutional variation in early WLST-N, (4) use of multimodal prognostication, and (5) use of sedative medications in patients with early WLST-N. Analysis included descriptive statistics and multivariable logistic regression.

RESULTS

We included 1,040 patients (mean age was 65 years, 37% were female, 41% were White, and 44% presented with arrest due to ventricular fibrillation) admitted to nine hospitals. Early WLST-N accounted for 24% (n = 154) of patient deaths and occurred in half (51%) of patients with WLST-N. Factors associated with early WLST-N in multivariate regressions were older age (odds ratio [OR] 1.02, 95% confidence interval [CI]: 1.01-1.03), preexisting do-not-attempt-resuscitation orders (OR 4.67, 95% CI: 1.55-14.01), bilateral absent pupillary reflexes (OR 2.4, 95% CI: 1.42-4.10), and lack of neurological consultation (OR 2.60, 95% CI: 1.52-4.46). The proportion of patients with early WLST-N among all OHCA admissions ranged from 19-60% between institutions. A head computed tomography scan was obtained in 54% (n = 84) of patients with early WLST-N; 22% (n = 34) and 5% (n = 8) underwent ≥ 1 and ≥ 2 additional prognostic tests, respectively. Prognostic tests were more frequently performed when neurological consultation occurred. Most patients received sedating medications (90%) within 24 h before early WLST-N; the median time from last sedation to early WLST-N was 4.2 h (interquartile range 0.4-15).

CONCLUSIONS

Nearly one quarter of deaths after OHCA were due to early WLST-N. The presence of concerning neurological examination findings appeared to impact early WLST-N decisions, even though these are not fully reliable in this time frame. Lack of neurological consultation was associated with early WLST-N and resulted in underuse of guideline-concordant multimodal prognostication. Sedating medications were often coadministered prior to early WLST-N and may have further confounded the neurological examination. Standardizing prognostication, restricting early WLST-N, and a multidisciplinary approach including neurological consultation might improve outcomes after OHCA.

Brain monitoring after cardiac arrest

PURPOSE OF REVIEW

To describe the available neuromonitoring tools in patients who are comatose after resuscitation from cardiac arrest because of hypoxic-ischemic brain injury (HIBI).

RECENT FINDINGS

Electroencephalogram (EEG) is useful for detecting seizures and guiding antiepileptic treatment. Moreover, specific EEG patterns accurately identify patients with irreversible HIBI. Cerebral blood flow (CBF) decreases in HIBI, and a greater decrease with no CBF recovery indicates poor outcome. The CBF autoregulation curve is narrowed and right-shifted in some HIBI patients, most of whom have poor outcome. Parameters derived from near-infrared spectroscopy (NIRS), intracranial pressure (ICP) and transcranial Doppler (TCD), together with brain tissue oxygenation, are under investigation as tools to optimize CBF in patients with HIBI and altered autoregulation. Blood levels of brain biomarkers and their trend over time are used to assess the severity of HIBI in both the research and clinical setting, and to predict the outcome of postcardiac arrest coma. Neuron-specific enolase (NSE) is recommended as a prognostic tool for HIBI in the current postresuscitation guidelines, but other potentially more accurate biomarkers, such as neurofilament light chain (NfL) are under investigation.

SUMMARY

Neuromonitoring provides essential information to detect complications, individualize treatment and predict prognosis in patients with HIBI.

Are serial neuron-specific enolase levels associated with neurologic outcome of ECPR patients: A retrospective multicenter observational study

AIM OF THE STUDY

This study aims to evaluate whether neuron-specific enolase (NSE) level at 48 h after extracorporeal cardiopulmonary resuscitation (ECPR) is associated with neurologic outcomes at 6 months after hospital discharge.

METHODS

This was a retrospective, multicenter, observational study of adult patients who received ECPR between May 2010 and December 2016. In the two hospitals involved in this study, NSE measurements were a routine part of the protocol for patients who received ECPR. Serial NSE levels were measured in all patients with ECPR. NSE levels were measured 24, 48, and 72 h after ECPR. The primary outcome was Cerebral Performance Categories (CPC) scale at 6 months after hospital discharge according to NSE levels at 48 h after ECPR.

RESULTS

At follow-up 6 months after hospital discharge, favorable neurologic outcomes of CPC 1 or 2 were observed in 9 (36.0%) of the 25 patients, and poor neurologic outcomes of CPC 3, 4, or 5 were observed in 16 (64%) patients. NSE levels at 24 h in the favorable and poor neurologic outcome groups were 58.3 (52.5-73.2) μg/L and 64.2 (37.9-89.8) μg/L, respectively (p = 0.95). NSE levels at 48 h in the favorable and poor neurologic outcome groups were 52.1 (22.3-64.9) μg/L and 302.0 (62.8-360.2) μg/L, respectively (p = 0.01). NSE levels at 72 h were 37.2 (12.5-53.2) μg/L and 240.9 (75.3-370.0) μg/L, respectively (p < 0.01). In receiver operating characteristic (ROC) curve analysis, as the predictor of poor outcome, the optimal cut-off value for NSE level at 48 h was 140.5 μg/L, and the area under the curve (AUC) was 0.844 (p < 0.01). The optimal cut-off NSE level at 72 h was 53.2 μg/L, and the AUC was 0.897 (p < 0.01).

CONCLUSIONS

NSE level at 72 h displayed the highest association with neurologic outcome after ECPR, and NSE level at 48 h was also associated with neurologic outcome after ECPR.

The neuro-prognostic value of the ion shift index in cardiac arrest patients following extracorporeal cardiopulmonary resuscitation

BACKGROUND

The ion shift index (ISI) as a prognostic indicator that can show the severity of hypoxic-ischemic injury. We aimed to evaluate the performance of the ISI in predicting unfavorable neurological outcomes at hospital discharge in cardiac arrest (CA) patients following extracorporeal cardiopulmonary resuscitation (ECPR) and to compare its performance to other prognostic predictors.

METHODS

This was a retrospective observational study including adult CA patients treated with ECPR between January 2018 and December 2022 in a tertiary hospital. Data regarding clinical characteristics and laboratory parameters were collected from medical records. The ISI was determined based on the first available serum electrolyte levels after ECPR. The primary outcome was unfavorable neurological status at hospital discharge, defined as Cerebral Performance Categories 3-5. Comparisons of the characteristics between the two groups were made using the χ2 test for categorical variables and the t-test or non-parametric Mann-Whitney U-test for continuous variables, as appropriate. Correlation analysis was performed using Spearman's rank correlation coefficient. A two-tailed P-value <0.05 was considered statistically significant.

RESULTS

Among the 122 patients involved, 46 (37.7%) had out-of-hospital CA, and 88 had unfavorable neurological outcomes. The ISI was significantly higher in the unfavorable outcome group than in the favorable outcome group (3.74 [3.15-4.57] vs. 2.69 [2.51-3.07], P<0.001). A higher ISI level was independently related to unfavorable outcome (odds ratio=6.529, 95% confidence interval 2.239-19.044, P=0.001). An ISI level >3.12 predicted unfavorable outcomes with a sensitivity and specificity of 74.6% and 85.2%, respectively (P<0.001). The prognostic performance of ISI (area under the curve [AUC]=0.887) was similar to that of other predictors, such as gray-to-white matter ratio (AUC=0.850, P=0.433) and neuron-specific enolase (AUC=0.925, P=0.394).

CONCLUSION

ISI may be used as a prognostic biomarker to predict neurological outcomes in CA patients following ECPR.

Can Blood Ammonia Level, Prehospital Time, and Return of Spontaneous Circulation Predict Neurological Outcomes of Out-of-Hospital Cardiac Arrest Patients? A Nationwide, Retrospective Cohort Study

Background: This study aimed to test if blood ammonia levels at hospital arrival, considering prehospital time and the patient’s condition (whether return of spontaneous circulation [ROSC] was achieved at hospital arrival), can predict neurological outcomes after out-of-hospital cardiac arrest (OHCA). Methods: This was a retrospective cohort study on data from a nationwide OHCA registry in Japan. Patients over 17 years old and whose blood ammonia levels had been recorded were included. The primary outcome was favorable neurological outcome at 30 days after OHCA. Blood ammonia levels, prehospital time, and the combination of the two were evaluated using the receiver operating characteristic curve to predict favorable outcomes. Then, cut-off blood ammonia values were determined based on whether ROSC was achieved at hospital arrival. Results: Blood ammonia levels alone were sufficient to predict favorable outcomes. The overall cut-off ammonia value for favorable outcomes was 138 μg/dL; values were different for patients with ROSC (96.5 μg/dL) and those without ROSC (156 μg/dL) at hospital arrival. Conclusions: Our results using patient data from a large OHCA registry showed that blood ammonia levels at hospital arrival can predict neurological outcomes, with different cut-off values for patients with or without ROSC at hospital arrival.

Serum Neuron-Specific Enolase Thresholds for Predicting Postcardiac Arrest Outcome: A Systematic Review and Meta-analysis

BACKGROUND AND OBJECTIVES

To determine thresholds of serum neuron-specific enolase (NSE) for prediction of poor outcome after cardiac arrest with >95% specificity using a unique method of multiple thresholds meta-analysis.

METHODS

Data from a systematic review by the European Resuscitation Council (ERC 2014) were updated with literature searches from PubMed, Cochrane, and Scopus until August 2020. Search terms included the MeSH terms "heart arrest" and "biomarkers" and the text words "cardiac arrest," "neuron specific enolase," "coma" and "prognosis." Cohort studies with comatose cardiac arrest survivors aged >16 years undergoing targeted temperature management (TTM) and NSE levels within 96 hours of resuscitation were included. Poor outcome was defined as cerebral performance category 3-5 at hospital discharge or later. Studies without extractable contingency tables were excluded. A multiple thresholds meta-analysis model was used to generate summary receiver operating characteristic curves for various time points. NSE thresholds (and 95% prediction intervals) for >95% specificity were calculated. Evidence appraisal was performed using a method adapted from the American Academy of Neurology grading criteria.

RESULTS

Data from 11 studies (n = 1,982) at 0-24 hours, 21 studies (n = 2,815) at 24-48 hours, and 13 studies (n = 2,557) at 48-72 hours was analyzed. Areas under the curve for prediction of poor outcomes were significantly larger at 24-48 hours and 48-72 hours compared to 0-24 hours (0.82 and 0.83 vs 0.64). Quality of evidence was very low for most studies because of the risk of incorporation bias-knowledge of NSE levels potentially influenced life support withdrawal decisions. To minimize falsely pessimistic predictions, NSE thresholds at the upper 95% limit of prediction intervals are reported. For prediction of poor outcome with specificity >95%, upper limits of the prediction interval for NSE were 70.4 ng/mL at 24-48 hours and 58.6 ng/mL at 48-72 hours. Sensitivity analyses excluding studies with inconsistent TTM use or different outcome criteria did not substantially alter the results.

CONCLUSIONS

NSE thresholds for highly specific prediction of poor outcome are much higher than generally used. Future studies must minimize bias by masking treatment teams to the results of potential predictors and by prespecifying criteria for withdrawal of life support.

Prediction of delayed neuropsychiatric sequelae after carbon monoxide poisoning via serial determination of serum neuron-specific enolase levels

BACKGROUND

Neuron-specific enolase (NSE) is released into serum when nerve cells are damaged, and the levels thereof are used to determine neurological prognosis in patients who have suffered cardiac arrest or stroke. Delayed neuropsychiatric sequelae (DNS), a major complication of carbon monoxide poisoning (COP), can be caused by inflammatory response which is a mechanism of neuronal injury in cardiac arrest and stroke. NSE is known as a predictor of neurological prognosis in ischemic brain injury after cardiac arrest, and it is also reported as a predictor of DNS in acute COP. When serum NSE is measured serially in cardiac arrest patients, the best time to predict neurological prognosis is known at 48-72 h, but there are no studies analyzing serial serum NSE in acute COP. Thus, we explored whether serum NSE levels measured three times at 24 h intervals after COP predicted the development of DNS.

METHODS

This prospective observational study was conducted on patients treated for COP from May 2018 to April 2020 in a tertiary care hospital in Korea. Neuron-specific enolase levels were assessed 24, 48, and 72 h after presentation at hospital. We used logistic regression to explore the association between NSE levels and DNS development.

RESULTS

The NSE level was highest at 48 h, and the difference between the DNS group and the non-DNS group was greatest on the same time point. On multivariable logistic regression analysis, the NSE level at 48 h of >20.98 ng/mL (odds ratio [OR], 3.570; 95% confidence interval [CI], 1.412-9.026; P = .007) and the initial Glasgow Coma Scale (GCS) score of <9 (OR, 4.559; 95% CI, 1.658-0.12.540; P = .003) was statistically significant for DNS development.

CONCLUSION

Early identification of those who will experience DNS in acute COP patients is clinically important for deciding treatment. In this study, we revealed that NSE level of >20.98 ng/mL at 48 h time point can be used as an independent predictor of DNS (OR, 3.570; 95% CI, 1.412-9.026; P = .007; AUC, 0.648).

Neuron-specific enolase and long-term neurological outcome after OHCA - A validation study

AIMS

To investigate what NSE levels predict long-term neurological prognosis at 24, 48 and 72 hours after ROSC in a cohort of out-of-hospital cardiac arrest and to validate previously suggested NSE cut-offs, including the latest ERC guidelines (2021).

METHODS

Patients admitted to intensive care units in four hospitals in Southern Sweden between 2014-2018 were included. Blood samples were handled by a single local laboratory. The primary outcome was neurological outcome according to the Cerebral Performance Category (CPC) scale at 2-6 months after cardiac arrest.

RESULTS

368 patients were included for analysis. A ≤2% false positive rate for the prediction of poor neurological outcome was achieved with an NSE cut-off value of >101 μg/L at 48 hours and >80 μg/L at 72 hours. The cut-off suggested by the recent ERC guidelines of >60 μg/L at 48 and/or 72 hours generated a false positive rate of 4.3% (95 %CI 0.9-7.4%).

CONCLUSION

A local validation study of the ability of serum levels of neuron-specific enolase to predict long-term poor neurological outcome after out-of-hospital cardiac arrest generated higher cut-offs than suggested by previous publications.

Relationship between miR-29a levels in the peripheral blood and sepsis-related encephalopathy

OBJECTIVE

This study aimed to explore the relationship between peripheral blood miR-29a and sepsis-related encephalopathy (SAE).

METHODS

A total of 120 patients with sepsis admitted to our hospital from March 2018 to October 2019 were selected as research subjects. They were divided into a SAE group (30 cases) and an unrelated encephalopathy group (90 cases) according to whether the patients were complicated with SAE. The levels of miR-29a in the peripheral blood, neuron-specific enolase (NSE), S100β calcium binding protein (S100β) and interleukin-6 (IL-6) in serum were determined, and the relationship between miR-29a in the peripheral blood and the diagnosis and prognosis prediction in SAE patients was analyzed.

RESULTS

Compared with the unrelated encephalopathy group, the levels of miR-29a in peripheral blood, NSE, S100β and IL-6 in serum of patients in the SAE group were elevated notably. miR-29a in the peripheral blood, and NSE, S100β, IL-6 in the serum of patients who died and survived within 28 days were detected, and the levels of these four indexes in the death group were significantly higher than those in the survival group. Correlation analysis revealed that miR-29a in the peripheral blood was positively correlated with the levels of NSE, S100β and IL-6 in serum. According to Receiver Operating Characteristic (ROC) curve analysis, miR-29a in the peripheral blood can be used as a potential biomarker to predict whether sepsis is complicated with SAE and the relative prognosis.

CONCLUSION

miR-29a is closely associated with the development of SAE, and miR-29a in the peripheral blood can be used as a potential biological index to predict whether sepsis is complicated with SAE and indications of a poor prognosis.

European Resuscitation Council and European Society of Intensive Care Medicine guidelines 2021: post-resuscitation care

The European Resuscitation Council (ERC) and the European Society of Intensive Care Medicine (ESICM) have collaborated to produce these post-resuscitation care guidelines for adults, which are based on the 2020 International Consensus on Cardiopulmonary Resuscitation Science with Treatment Recommendations. The topics covered include the post-cardiac arrest syndrome, diagnosis of cause of cardiac arrest, control of oxygenation and ventilation, coronary reperfusion, haemodynamic monitoring and management, control of seizures, temperature control, general intensive care management, prognostication, long-term outcome, rehabilitation and organ donation.

European Resuscitation Council and European Society of Intensive Care Medicine Guidelines 2021: Post-resuscitation care

The European Resuscitation Council (ERC) and the European Society of Intensive Care Medicine (ESICM) have collaborated to produce these post-resuscitation care guidelines for adults, which are based on the 2020 International Consensus on Cardiopulmonary Resuscitation Science with Treatment Recommendations. The topics covered include the post-cardiac arrest syndrome, diagnosis of cause of cardiac arrest, control of oxygenation and ventilation, coronary reperfusion, haemodynamic monitoring and management, control of seizures, temperature control, general intensive care management, prognostication, long-term outcome, rehabilitation, and organ donation.

Role of the ratio of NSE serum concentration in evaluating the therapeutic effect on metastatic neuroendocrine neoplasms of the liver

BACKGROUND

Neuron-specific enolase (NSE) is one of the biomarkers of neuroendocrine neoplasms (NEN). Its level of evidence is significantly lower than some other biomarkers. However, the ratio of NSE serum concentration (NSE ratio) before and after the treatment cycle may be a good tool for evaluating the therapeutic effect of metastatic neuroendocrine neoplasms of the liver (MNENOL).

METHODS

We collected clinical cases of NEN with liver metastases, calculating the ratio of NSE in each case before and after the treatment cycle, using thin-slice computed tomography or magnetic resonance imaging as a reference to evaluate the therapeutic effect. We analyzed the correlation between NSE ratio and NSE serum concentration and curative effect, and then compared the evaluation performance of the two.

RESULTS

We found that increase in the NSE ratio is a risk factor for the progression of MNENOL. Compared with NSE, NSE ratio has a greater advantage in evaluating the effect of MNENOL. NSE ratio is related to the curative effect of NEN, and the correlation is better than that of NSE. When judging whether NEN has new metastasis, the NSE ratio shows a similar effect to NSE, and there is no significant difference between the two.

CONCLUSION

NSE ratio is more effective than NSE in evaluating the therapeutic effect of MNENOL, but it is not significantly different from NSE in terms of predicting new metastases.

Adult Advanced Life Support: 2020 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science with Treatment Recommendations

This 2020 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations for advanced life support includes updates on multiple advanced life support topics addressed with 3 different types of reviews. Topics were prioritized on the basis of both recent interest within the resuscitation community and the amount of new evidence available since any previous review. Systematic reviews addressed higher-priority topics, and included double-sequential defibrillation, intravenous versus intraosseous route for drug administration during cardiac arrest, point-of-care echocardiography for intra-arrest prognostication, cardiac arrest caused by pulmonary embolism, postresuscitation oxygenation and ventilation, prophylactic antibiotics after resuscitation, postresuscitation seizure prophylaxis and treatment, and neuroprognostication. New or updated treatment recommendations on these topics are presented. Scoping reviews were conducted for anticipatory charging and monitoring of physiological parameters during cardiopulmonary resuscitation. Topics for which systematic reviews and new Consensuses on Science With Treatment Recommendations were completed since 2015 are also summarized here. All remaining topics reviewed were addressed with evidence updates to identify any new evidence and to help determine which topics should be the highest priority for systematic reviews in the next 1 to 2 years.

Adult Advanced Life Support: 2020 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations

This 2020 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations for advanced life support includes updates on multiple advanced life support topics addressed with 3 different types of reviews. Topics were prioritized on the basis of both recent interest within the resuscitation community and the amount of new evidence available since any previous review. Systematic reviews addressed higher-priority topics, and included double-sequential defibrillation, intravenous versus intraosseous route for drug administration during cardiac arrest, point-of-care echocardiography for intra-arrest prognostication, cardiac arrest caused by pulmonary embolism, postresuscitation oxygenation and ventilation, prophylactic antibiotics after resuscitation, postresuscitation seizure prophylaxis and treatment, and neuroprognostication. New or updated treatment recommendations on these topics are presented. Scoping reviews were conducted for anticipatory charging and monitoring of physiological parameters during cardiopulmonary resuscitation. Topics for which systematic reviews and new Consensuses on Science With Treatment Recommendations were completed since 2015 are also summarized here. All remaining topics reviewed were addressed with evidence updates to identify any new evidence and to help determine which topics should be the highest priority for systematic reviews in the next 1 to 2 years.

Prediction of poor neurological outcome in comatose survivors of cardiac arrest: a systematic review

Purpose

To assess the ability of clinical examination, blood biomarkers, electrophysiology, or neuroimaging assessed within 7 days from return of spontaneous circulation (ROSC) to predict poor neurological outcome, defined as death, vegetative state, or severe disability (CPC 3–5) at hospital discharge/1 month or later, in comatose adult survivors from cardiac arrest (CA).

Methods

PubMed, EMBASE, Web of Science, and the Cochrane Database of Systematic Reviews (January 2013–April 2020) were searched. Sensitivity and false-positive rate (FPR) for each predictor were calculated. Due to heterogeneities in recording times, predictor thresholds, and definition of some predictors, meta-analysis was not performed.

Results

Ninety-four studies (30,200 patients) were included. Bilaterally absent pupillary or corneal reflexes after day 4 from ROSC, high blood values of neuron-specific enolase from 24 h after ROSC, absent N20 waves of short-latency somatosensory-evoked potentials (SSEPs) or unequivocal seizures on electroencephalogram (EEG) from the day of ROSC, EEG background suppression or burst-suppression from 24 h after ROSC, diffuse cerebral oedema on brain CT from 2 h after ROSC, or reduced diffusion on brain MRI at 2–5 days after ROSC had 0% FPR for poor outcome in most studies. Risk of bias assessed using the QUIPS tool was high for all predictors.

Conclusion

In comatose resuscitated patients, clinical, biochemical, neurophysiological, and radiological tests have a potential to predict poor neurological outcome with no false-positive predictions within the first week after CA. Guidelines should consider the methodological concerns and limited sensitivity for individual modalities. (PROSPERO CRD42019141169)

Electronic supplementary material

The online version of this article (10.1007/s00134-020-06198-w) contains supplementary material, which is available to authorized users.

Neuroprognostication Practices in Postcardiac Arrest Patients: An International Survey of Critical Care Providers

OBJECTIVES

To characterize approaches to neurologic outcome prediction by practitioners who assess prognosis in unconscious cardiac arrest individuals, and assess compliance to available guidelines.

DESIGN

International cross-sectional study.

SETTING

We administered a web-based survey to members of Neurocritical Care Society, Society of Critical Care Medicine, and American Academy of Neurology who manage unconscious cardiac arrest patients to characterize practitioner demographics and current neuroprognostic practice patterns.

SUBJECTS

Physicians that are members of aforementioned societies who care for successfully resuscitated cardiac arrest individuals.

INTERVENTIONS

Not applicable.

MEASUREMENTS AND MAIN RESULTS

A total of 762 physicians from 22 countries responses were obtained. A significant proportion of respondents used absent corneal reflexes (33.5%) and absent pupillary reflexes (36.2%) at 24 hours, which is earlier than the recommended 72 hours in the standard guidelines. Certain components of the neurologic examination may be overvalued, such as absent motor response or extensor posturing, which 87% of respondents considered being very or critically important prognostic indicators. Respondents continue to rely on myoclonic status epilepticus and neuroimaging, which were favored over median nerve somatosensory evoked potentials for prognostication, although the latter has been demonstrated to have a higher predictive value. Regarding definitive recommendations based on poor neurologic prognosis, most physicians seem to wait until the postarrest timepoints proposed by current guidelines, but up to 25% use premature time windows.

CONCLUSIONS

Neuroprognostic approaches to hypoxic-ischemic encephalopathy vary among physicians and are often not consistent with current guidelines. The overall inconsistency in approaches and deviation from evidence-based recommendations are concerning in this disease state where mortality is so integrally related to outcome prediction.

The usefulness of neuron-specific enolase in cerebrospinal fluid to predict neurological prognosis in cardiac arrest survivors who underwent target temperature management: A prospective observational study

AIM

Cerebrospinal fluid (CSF) neuron-specific enolase (NSE) levels increase ahead of serum NSE levels in patients with severe brain injury. We examined the prognostic performance between CSF NSE and serum NSE levels in out-of-cardiac arrest (OHCA) survivors who had undergone target temperature management (TTM).

METHODS

This single-centre prospective observational study included OHCA patients who had undergone TTM. NSE levels were assessed in blood and CSF samples obtained immediately (Day 0), and at 24 h (Day 1), 48 h (Day 2), and 72 h (Day 3) after return of spontaneous circulation (ROSC). The primary outcome was the 6-month neurological outcome.

RESULTS

We enrolled 34 patients (males, 24; 70.6%), and 16 (47.1%) had a poor neurologic outcome. CSF NSE and serum NSE values were significantly higher in the poor outcome group compared to the good outcome group at each time point, except for serum Day 0. CSF NSE and serum NSE had an area under curve (AUC) of 0.819-0.972 and 0.648-0.920, respectively. CSF NSE prognostic performances were significantly higher than serum NSE levels at Day 1 and showed excellent AUC values (0.969; 95% confidence interval [CI] 0.844-0.999) and high sensitivity (93.8%; 95% CI 69.8-99.8) at 100% specificity.

CONCLUSION

We found CSF NSE values were highly predictive and sensitive markers of 6-month poor neurological outcome in OHCA survivors treated with TTM at Day 1 after ROSC. Therefore, CSF NSE levels at day 1 after ROSC can be a useful early prognosticator in OHCA survivors.

Reduced Neuron-Specific Enolase Levels in Chronic Severe Traumatic Brain Injury

Growing evidence suggests that pathophysiological mechanisms leading to neurodegeneration and neuronal loss take place during the chronic phase of a severe traumatic brain injury (TBI). In this study we evaluated a well-established marker of brain injury, the neuron-specific enolase (NSE), in the serum of 51 patients with severe TBI (86% males, mean age 33.8 ± 11.1 years). All patients' samples were available from a previous study and the mean time between TBI and blood sample collection was 23.2 ± 31.5 months (28 patients were evaluated within 12 months of TBI and 23 patients were evaluated ≥12 months after TBI). Patients' NSE levels were compared with those obtained from 30 age and sex-matched healthy controls (87% males, 33.7 ± 11.3 years). We found that NSE levels were significantly lower in patients (median 3.2 ng/mL; 25th, 75th percentile 2.5, 5.1) than in healthy controls (median 4.1 ng/mL; 25th, 75th percentile 3.1, 7.5) (p = 0.026). This finding was mainly driven by data from the chronic patients, that is, those who experienced their TBI at least 12 months before the evaluation. Indeed, these patients had significantly lower NSE levels (median 2.6 ng/mL; 25th, 75th percentile 1.9, 4) than healthy controls (p < 0.01). On the other hand, NSE levels evaluated in patients <12 months from TBI (median 3.9 ng/mL; 25th, 75th percentile 2.8, 5.7) did not significantly differ from controls (p = 0.3). These findings possibly reflect a progressive brain atrophy with reduced baseline NSE release in the chronic phase of a severe TBI.

Non-Coding RNAs to Aid in Neurological Prognosis after Cardiac Arrest

Cardiovascular disease in general, and sudden cardiac death in particular, have an enormous socio-economic burden worldwide. Despite significant efforts to improve cardiopulmonary resuscitation, survival rates remain low. Moreover, patients who survive to hospital discharge have a high risk of developing severe physical or neurological symptoms. Being able to predict outcomes after resuscitation from cardiac arrest would make it possible to tailor healthcare approaches, thereby maximising efforts for those who would mostly benefit from aggressive therapy. However, the identification of patients at risk of poor recovery after cardiac arrest is still a challenging task which could be facilitated by novel biomarkers. Recent investigations have recognised the potential of non-coding RNAs to aid in outcome prediction after cardiac arrest. In this review, we summarize recent discoveries and propose a handful of novel perspectives for the use of non-coding RNAs to predict outcome after cardiac arrest, discussing their use for precision medicine.