Can early serum levels of S100B protein predict the prognosis of patients with out-of-hospital cardiac arrest?

Intra-arrest blood-based biomarkers for out-of-hospital cardiac arrest: A scoping review

Objective

Blood-based biomarkers play a central role in the diagnosis and treatment of critically ill patients, yet none are routinely measured during the intra-arrest phase of out-of-hospital cardiac arrest (OHCA). Our objective was to describe methodological aspects, sources of evidence, and gaps in research surrounding intra-arrest blood-based biomarkers for OHCA.

Methods

We used scoping review methodology to summarize existing literature. The protocol was designed a priori following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Extension for Scoping Reviews. Inclusion criteria were peer-reviewed scientific studies on OHCA patients with at least one blood draw intra-arrest. We excluded in-hospital cardiac arrest and animal studies. There were no language, date, or study design exclusions. We conducted an electronic literature search using PubMed and Embase and hand-searched secondary literature. Data charting/synthesis were performed in duplicate using standardized data extraction templates.

Results

The search strategy identified 11,834 records, with 118 studies evaluating 105 blood-based biomarkers included. Only eight studies (7%) had complete reporting. The median number of studies per biomarker was 2 (interquartile range 1-4). Most studies were conducted in Asia (63 studies, 53%).  Only 22 studies (19%) had blood samples collected in the prehospital setting, and only six studies (5%) had samples collected by paramedics. Pediatric patients were included in only three studies (3%). Out of eight predefined biomarker categories of use, only two were routinely assessed: prognostic (97/105, 92%) and diagnostic (61/105, 58%).

Conclusions

Despite a large body of literature on intra-arrest blood-based biomarkers for OHCA, gaps in methodology and knowledge are widespread.

Evaluation of Serum Biomarkers and Electroencephalogram to Determine Survival Outcomes in Pediatric Post-Cardiac-Arrest Patients

Cardiac arrest causes primary and secondary brain injuries. We evaluated the association between neuron-specific enolase (NSE), serum S-100B (S100B), electroencephalogram (EEG) patterns, and post-cardiac arrest outcomes in pediatric patients. A prospective observational study was conducted in the pediatric intensive care unit and included 41 post-cardiac arrest patients who underwent EEG and serum sampling for NSE and S100B. The participants were aged 1 month to 18 years who experienced cardiac arrest and underwent CPR after a sustained return of spontaneous circulation for ≥48 h. Approximately 19.5% (n = 8) of patients survived until ICU discharge. Convulsions and sepsis were significantly associated with higher mortality (relative risk: 1.33 [95% CI = 1.09-1.6] and 1.99 [95% CI = 0.8-4.7], respectively). Serum NSE and S100B levels were not statistically associated with the outcome (p = 0.278 and 0.693, respectively). NSE levels were positively correlated with the duration of CPR. EEG patterns were significantly associated with the outcome (p = 0.01). Non-epileptogenic EEG activity was associated with the highest survival rate. Post-cardiac arrest syndrome is a serious condition with a high mortality rate. Management of sepsis and convulsions affects prognosis. We believe that NSE and S100B may have no benefit in survival evaluation. EEG can be considered for post-cardiac arrest patients.

Serum S100 Protein Is a Reliable Predictor of Brain Injury After Out-of-Hospital Cardiac Arrest: A Cohort Study

Purpose: To evaluate serum S100 protein at hospital admission and after 48 h in early neuroprognostication of comatose survivors of out-of-hospital cardiac arrest (OHCA). Methods: The study included 48 consecutive patients after OHCA, who survived for at least 72 h after the event. The patients were divided based on their best cerebral performance category (CPC) achieved over a 30 day follow-up period: favorable neurological outcome (CPC 1-2) vs. unfavorable neurological outcome (CPC 3-4). Predictors of an unfavorable neurological outcome were identified by multivariable regression analysis. Analysis of the receiver operating characteristic curve (ROC) was used to determine the cut-off value for S100, having a 0% false-positive prediction rate. Results: Of the 48 patients, 30 (63%) had a favorable and 18 (38%) had an unfavorable neurological outcome. Eleven patients (23%) died over the 30 day follow-up. Increased S100 levels at 48 h after OHCA, but not the baseline S100 levels, were independently associated with unfavorable neurological outcome, with an area under the ROC curve of 0.85 (confidence interval 0.74-0.96). A 48 h S100 value ≥0.37 μg/L had a specificity of 100% and sensitivity of 39% in predicting an unfavorable 30 day neurological outcome. Conclusion: This study showed that S100 values assessed 48 h after an OHCA could independently predict an unfavorable neurological outcome at 30 days.

Prognostic value of serum biomarkers of cerebral injury in classifying neurological outcome after paediatric resuscitation

AIM

To investigate if the serum biomarkers of cerebral injury, neuron-specific enolase and S100b protein, may classify unfavourable neurological outcome after paediatric cardiac arrest.

METHODS

We performed a retrospective study of neuron-specific enolase and S100b measurements from 95 children treated in our paediatric cardiac intensive care unit after cardiac arrest. Neurological outcome at discharge was evaluated using the paediatric cerebral performance category scale, with unfavourable outcome defined as a change of >1 compared to pre-arrest status or death.

RESULTS

Fifty-eight patients (61.1%) survived to discharge with 48 (50.5%) having a favourable neurological outcome. We observed significantly higher levels of both biomarkers in the unfavourable outcome group at designated time points (neuron-specific enolase at 24, 48, and 72h and S100b at 12, 24, and 48h after cardiac arrest, p<0.05). Receiver operating characteristic areas under the curve for neuron-specific enolase were 0.83, 0.80, and 0.73 at time points 24, 48, and 72h and 0.87, 0.81, and 0.82 for S100b at 12, 24, and 48h after cardiac arrest, respectively. Neuron-specific enolase measurement at 24h after cardiac arrest was an independent predictor of unfavourable outcome in a multivariable analysis.

CONCLUSIONS

Neuron-specific enolase and S100b classify unfavourable neurological outcome in this large paediatric cardiac arrest cohort. Further multi-institutional prospective studies to comprehensively evaluate the diagnostic accuracy of these biomarkers under various clinical conditions and to determine reliable cut-off values in children are warranted.

Neurology of cardiopulmonary resuscitation

This chapter aims to provide an up-to-date review of the science and clinical practice pertaining to neurologic injury after successful cardiopulmonary resuscitation. The past two decades have seen a major shift in the science and practice of cardiopulmonary resuscitation, with a major emphasis on postresuscitation neurologic care. This chapter provides a nuanced and thoughtful historic and bench-to-bedside overview of the neurologic aspects of cardiopulmonary resuscitation. A particular emphasis is made on the anatomy and pathophysiology of hypoxic-ischemic encephalopathy, up-to-date management of survivors of cardiopulmonary resuscitation, and a careful discussion on neurologic outcome prediction. Guidance to practice evidence-based clinical care when able and thoughtful, pragmatic suggestions for care where evidence is lacking are also provided. This chapter serves as both a useful clinical guide and an updated, thorough, and state-of-the-art reference on the topic for advanced students and experienced practitioners in the field.

Predicting the outcomes for out-of-hospital cardiac arrest patients using multiple biomarkers and suspension microarray assays

Predicting the prognosis for cardiac arrest is still challenging. Combining biomarkers from diverse pathophysiological pathways may provide reliable indicators for the severity of injury and predictors of long-term outcomes. We investigated the feasibility of using a multimarker strategy with key independent biomarkers to improve the prediction of outcomes in cardiac arrest. Adult out-of-hospital cardiac arrest patients with sustained return of spontaneous circulation were prospectively enrolled in this study. Blood samples were taken at 2 and 24 hours after cardiac arrest. Suspension microarray assays were used to test 21 different biomarkers. A total of 99 patients were enrolled, 45 of whom survived to hospital discharge. We identified 11 biomarkers that, when combined with clinical variables and factors of APACHE II score and history of arrhythmia, were independent determinants for outcome of in-hospital mortality (concordance = 0.9249, standard error = 0.0779). Three biomarkers combined with APACHE II and age were independent determinants for favorable neurological outcome at hospital discharge (area under the receiver-operator characteristic curve, 0.938; 95% confidence interval, 0.854 ~ 1.0). In conclusion, a systemic multiple biomarker approach using suspension microarray assays can identify independent predictors and model the outcomes of cardiac arrest patients during the post-cardiac arrest period.

Predictive value of S100-B and copeptin for outcomes following seizure: the BISTRO International Cohort Study

Objective

To evaluate the performance of S100-B protein and copeptin, in addition to clinical variables, in predicting outcomes of patients attending the emergency department (ED) following a seizure.

Methods

We prospectively included adult patients presented with an acute seizure, in four EDs in France and the United Kingdom. Participants were followed up for 28 days. The primary endpoint was a composite of seizure recurrence, all-cause mortality, hospitalization or rehospitalisation, or return visit in the ED within seven days.

Results

Among the 389 participants included in the analysis, 156 (40%) experienced the primary endpoint within seven days and 195 (54%) at 28 days. Mean levels of both S100-B (0.11 μg/l [95% CI 0.07–0.20] vs 0.09 μg/l [0.07–0.14]) and copeptin (23 pmol/l [9–104] vs 17 pmol/l [8–43]) were higher in participants meeting the primary endpoint. However, both biomarkers were poorly predictive of the primary outcome with a respective area under the receiving operator characteristic curve of 0.57 [0.51–0.64] and 0.59 [0.54–0.64]. Multivariable logistic regression analysis identified higher age (odds ratio [OR] 1.3 per decade [1.1–1.5]), provoked seizure (OR 4.93 [2.5–9.8]), complex partial seizure (OR 4.09 [1.8–9.1]) and first seizure (OR 1.83 [1.1–3.0]) as independent predictors of the primary outcome. A second regression analysis including the biomarkers showed no additional predictive benefit (S100-B OR 3.89 [0.80–18.9] copeptin OR 1 [1.00–1.00]).

Conclusion

The plasma biomarkers S100-B and copeptin did not improve prediction of poor outcome following seizure. Higher age, a first seizure, a provoked seizure and a partial complex seizure are independently associated with adverse outcomes.

Serum S100B protein could help to detect cerebral complications associated with extracorporeal membrane oxygenation (ECMO)

BACKGROUND

To investigate if serum S100B protein levels could early detect cerebral complications under treatment extracorporeal membrane oxygenation (ECMO).

METHODS

Serum S100B levels were measured over 5 days in 32 patients with cardiogenic and septic shock, including 15 patients who treated by ECMO and 17 who did not. Cerebral complications included hemorrhage, stroke, encephalopathy with myoclonus, and brain death. Delirium was identified by the positive Confusion Assessment Method in the ICU.

RESULTS

S100B levels were elevated in 24/32 patients (75 %) at ICU admission. Five patients developed cerebral complications (2 hemorrhages with 1 brain death, 1 encephalopathy with myoclonus in the ECMO group and 2 strokes in the non-ECMO group). At day 5, S100B levels were higher in the 5 patients with cerebral complications than in the 27 without cerebral complications, regardless of ECMO (0.426 [0.421, 0.652] vs. 0.102 [0.085, 0.135] μg/L, p = 0.011). S100B levels were also more elevated in 3 patients with than in 12 without cerebral complications associated with ECMO (0.799 [0.325, 0.965] vs. 0.102 [0.09, 0.607] μg/L, p = 0.033). S100B levels were not associated with delirium after sedation withdrawal.

CONCLUSIONS

Measurement serum S100B could be useful to detect cerebral complications in deeply sedated patients associated with ECMO but not for monitoring delirium after sedation withdrawal.

S100B protein in serum is elevated after global cerebral ischemic injury

BACKGROUND:

S100B protein in patients with cardiac arrest, hemorrhagic shock and other causes of global cerebral ischemic injury will be dramatically increased. Ischemic brain injury may elevate the level of serum S100B protein and the severity of brain damage.

METHODS:

This article is a critical and descriptive review on S100B protein in serum after ischemic brain injury. We searched Pubmed database with key words or terms such as “S100B protein”, “cardiac arrest”, “hemorrhagic shock” and “ischemia reperfusion injury” appeared in the last five years.

RESULTS:

S100B protein in patients with cardiac arrest, hemorrhagic shock and other causes of ischemic brain injury will be dramatically increased. Ischemic brain injury elevated the level of serum S100B protein, and the severity of brain damage.

CONCLUSION:

The level of S100B protein in serum is elevated after ischemic brain injury, but its mechanism is unclear.

Modeling serum level of s100β and bispectral index to predict outcome after cardiac arrest

OBJECTIVES

This study was designed to evaluate multimodal prognostication in patients after cardiac arrest (CA).

BACKGROUND

Accurate methods to predict outcome after CA are lacking.

METHODS

Seventy-five patients with CA treated with therapeutic hypothermia after cardiac resuscitation were enrolled in this prospective observational study. Serum levels of neuron-specific enolase (NSE) and neuron-enriched S100 beta (S100β) were measured 48 h after CA. Bispectral index (BIS) was continuously monitored during the first 48 h after CA. The primary endpoint was neurological outcome, as defined by the cerebral performance category (CPC) at 6-month follow-up: scores 1 or 2 indicated good outcome, and scores 3 to 5, poor outcome. The secondary endpoint was survival.

RESULTS

A total of 46 (61%) patients survived at 6 months and 41 (55%) patients had CPC 1 or 2. Levels of NSE and S100β were higher in patients with poor outcomes compared with patients with good outcomes (4-fold and 10-fold, respectively; p < 0.001). BIS was lower in patients with poor outcomes (10-fold; p < 0.001). NSE, S100β, or BIS alone predicted neurological outcome, with areas under the receiver-operating characteristic curve (AUC) above 0.80. Combined determination of S100β and BIS had an incremental predictive value (AUC: 0.95). S100β improved discriminations based on BIS (p = 0.0008), and BIS improved discriminations based on S100β (p < 10(-5)). Patients with S100β level above 0.03 μg/l and BIS below 5.5 had a 3.6-fold higher risk of poor neurological outcome (p < 0.0001). S100β and BIS predicted 6-month mortality (log-rank statistic: 50.41; p < 0.001).

CONCLUSIONS

Combined determination of serum level of S100β and BIS monitoring accurately predicts outcome after CA.

Outcome of accidental hypothermia with or without circulatory arrest: experience from the Danish Præstø Fjord boating accident

BACKGROUND

Resuscitation guidelines for the treatment of accidental hypothermia are based primarily on isolated cases. Mortality rates are high despite aggressive treatment aimed at restoring spontaneous circulation and normothermia.

METHODS

The present report is based on a boating accident where 15 healthy subjects (median age 16 (range 15-45) years) were immersed in 2 °C salt water. Seven victims were recovered in circulatory arrest with a median temperature of 18.4 °C (range 15.5-20.2 °C). They were all rewarmed with extracorporeal membrane oxygenation (ECMO) and were subsequently evaluated with advanced neuroradiological and functional testing. The remaining 7 had established spontaneous circulation without the use of ECMO. One victim drowned in the accident.

RESULTS

The victims that survived the accident without circulatory arrest were predominantly females with a higher body mass index. Victims with circulatory arrest pH on arrival was a median of 6.61 (range 6.43-6.94), with ECMO being established a median of 226 (178-241)min after the accident. Magnetic resonance spectroscopy showed neuronal dysfunction in five. In five victims initial normal white matter spectra progressed to show evidence of abnormal axonal membranes. Based on the seven-level Functional Independence Measure test functional outcome was good in six circulatory arrest victims and in all without circulatory arrest. Mild to moderate cognitive dysfunction was seen in six and severe dysfunction in one circulatory arrest victim.

CONCLUSION

Seven patients with profound accidental hypothermic circulatory arrest were successfully resuscitated using a management approach that included extracorporeal rewarming, followed by successive periods of therapeutic hypothermia and sedated normothermia and intensive neurorehabilitation. Seven other hypothermic victims (core temperature as low as 23 °C) that did not suffer circulatory arrest also survived the accident.

Serum S100B and neuron-specific enolase levels in normothermic and hypothermic infants after perinatal asphyxia

AIM

Serum S100B and neuron-specific enolase (NSE) levels are elevated after perinatal asphyxia, but the influence of hypothermia on these proteins has not been previously reported. The aim of this study was to evaluate the effect of systemic hypothermia on these protein levels after perinatal asphyxia, time course, and association with perinatal factors and neurodevelopmental outcome at 2 years of age.

METHODS

Serum S100B and NSE levels were measured at fixed time points in asphyxiated infants treated with standard intensive care on hypothermia (HT: n = 13) or normothermia (NT: n = 11).

RESULTS

Serum S100B and NSE levels were grossly elevated in both HT and NT groups. Compared with the values at 6 h of age, S100B values decreased over time in both groups (NT: p = 0.002, HT: p = 0.04). Serum S100B values were lower in HT infants compared with those in NT infants (p = 0.047 at 48 h). Serum S100B and NSE values were significantly higher in infants who died or developed severe neurological impairment (S100B, p < 0.05 at all time points; NSE, p = 0.036 at 24 h of age).

CONCLUSION

Both NSE and S100B levels are highly elevated following asphyxia. Serum S100B levels were lower in the HT group and strongly correlated with the neurodevelopmental outcome.

The significance of protein S-100B testing in cardiac arrest patients

Cardiac arrest often represents the first expression of an underlying cardiac disease. Despite advances in neurocritical care, the neurological assessment of cardiac arrest patients relies on clinical, instrumental and biochemical parameters. The clinical significance of S-100 calcium binding protein B (S-100B) has substantially increased throughout several areas of clinical neuroscience, but reliable evidences attest it can be used as a reliable and early predictor of poor physiological and cognitive neurological outcomes after cardiac arrest.