S-100B and neuron-specific enolase as predictors of neurological outcome in patients after cardiac arrest and return of spontaneous circulation: a systematic review

Kallistatin deficiency exacerbates neuronal damage after cardiac arrest

The purpose of study was to evaluate that kallistatin deficiency causes excessive production of reactive oxygen species and exacerbates neuronal injury after cardiac arrest. For in vitro study, kallistatin knockdown human neuronal cells were given ischemia-reperfusion injury, and the oxidative stress and apoptosis were evaluated. For clinical study, cardiac arrest survivors admitted to the ICU were divided into the good (CPC 1-2) and poor (CPC 3-5) 6-month neurological outcome groups. The serum level of kallistatin, Nox-1, H2O2 were measured. Nox-1 and H2O2 levels were increased in the kallistatin knockdown human neuronal cells with ischemia-reperfusion injury (p < 0.001) and caspase-3 was elevated and apoptosis was promoted (SERPINA4 siRNA: p < 0.01). Among a total of 62 cardiac arrest survivors (16 good, 46 poor), serum kallistatin were lower, and Nox-1 were higher in the poor neurological group at all time points after admission to the ICU (p = 0.013 at admission; p = 0.020 at 24 h; p = 0.011 at 72 h). At 72 h, H2O2 were higher in the poor neurological group (p = 0.038). Kallistatin deficiency exacerbates neuronal ischemia-reperfusion injury and low serum kallistatin levels were associated with poor neurological outcomes in cardiac arrest survivors.

Post Cardiac Arrest Care in the Cardiac Intensive Care Unit

PURPOSE OF REVIEW

Cardiac arrests constitute a leading cause of mortality in the adult population and cardiologists are often tasked with the management of patients following cardiac arrest either as a consultant or primary provider in the cardiac intensive care unit. Familiarity with evidence-based practice for post-cardiac arrest care is a requisite for optimizing outcomes in this highly morbid group. This review will highlight important concepts necessary to managing these patients.

RECENT FINDINGS

Emerging evidence has further elucidated optimal care of post-arrest patients including timing for routine coronary angiography, utility of therapeutic hypothermia, permissive hypercapnia, and empiric aspiration pneumonia treatment. The complicated state of multi-organ failure following cardiac arrest needs to be carefully optimized by the clinician to prevent further neurologic injury and promote systemic recovery. Future studies should be aimed at understanding if these findings extend to specific patient populations, especially those at the highest risk for poor outcomes.

Oxidative Stress and Indicators of Brain Damage Following Pediatric Heart Surgery

Pediatric cardiac surgery induces an increased oxidative stress (OS) response. Increased OS is associated with poor neurologic outcomes in neonatal populations with similar patterns of brain injury. We investigated OS and brain injury in infants undergoing heart surgery. Patients 6 months or younger, undergoing cardiac surgery with or without cardiopulmonary bypass (CPB), were included in this prospective, observational study. Patients were divided into infant (30 days−6 months) and neonatal (<30 days) groups for analysis. Urine OS biomarker 8-iso-prostaglandin F2α (8-iso-PGF2α) was quantified pre-surgery and at 0 and 24 h post-surgery. A serum brain damage biomarker S100B protein was also measured pre-surgery and at 0 and 72 h post-surgery. Amplitude-integrated electroencephalography during surgery was analyzed. Neuropsychological evaluation using the Bayley III or Vineland test was performed in all patients at 24 months of age. Sixty-two patients were included, 44 of whom underwent follow-up neurologic evaluation. 8-iso-PGF2α and S100B levels were increased after surgery. Postoperative levels of S100B were positively correlated with 8-iso-PGF2α levels 24 h after surgery (rho = 0.5224; p = 0.0261). There was also a correlation between immediate post-surgery levels of 8-iso-PGF2α and intra-surgery seizure burden (rho = 0.4285, p = 0.0205). Patients with an abnormal neurological evaluation had increased levels of S100B 72 h after surgery (p = 0.048). 8-iso-PGF2α levels 24 h after surgery were also related to abnormal neurologic outcomes. Levels of 8-iso-PGF2α following pediatric cardiac surgery are associated with several indicators of brain injury including brain damage biomarkers, intra-operative seizures, and abnormal neurological evaluation at follow-up, suggesting the importance of oxidative stress response in the origin of brain damage in this population.

Ubiquinol (reduced coenzyme Q10) as a metabolic resuscitator in post-cardiac arrest: A randomized, double-blind, placebo-controlled trial

INTRODUCTION

Ubiquinol (reduced coenzyme Q10) is essential for adequate aerobic metabolism. The objective of this trial was to determine whether ubiquinol administration in patients resuscitated from cardiac arrest could increase physiological coenzyme Q10 levels, improve oxygen consumption, and reduce neurological biomarkers of injury.

MATERIALS AND METHODS

This was a randomized, double-blind, placebo-controlled trial in patients successfully resuscitated from cardiac arrest. Patients were randomized to receive enteral ubiquinol (300 mg) or placebo every 12 h for up to 7 days. The primary endpoint was total coenzyme Q10 plasma levels at 24 h after enrollment. Secondary endpoints included neuron specific enolase, S100B, lactate, cellular and global oxygen consumption, neurological status, and in-hospital mortality.

RESULTS

Forty-three patients were included in the modified intention-to-treat analysis. Median coenzyme Q10 levels were significantly higher in the ubiquinol group as compared to the placebo group at 24 h (441 [IQR, 215-510] ηg/mL vs. 113 [IQR, 94-208] ηg/mL, P < 0.001). Similar results were observed at 48 and 72 h. There were no differences between the two groups in any of the secondary endpoints. Median neuron specific enolase levels were not different between the two groups at 24 h (16.8 [IQR, 9.5-19.8] ηg/mL vs. 8.2 [IQR, 4.3-19.1] ηg/mL, P = 0.61).

CONCLUSIONS

Administration of enteral ubiquinol increased plasma coenzyme Q10 levels in post-cardiac arrest patients as compared to placebo. There were no differences in neurological biomarkers and oxygen consumption between the two groups.

Biomarkers Facilitate the Assessment of Prognosis in Critically Ill Patients with Primary Brain Injury: A Cohort Study

Primary injuries to the brain are common causes of hospitalization of patients in intensive care units (ICU). The Acute Physiology and Chronic Health Evaluation (APACHE) II scoring system is widely used for prognostication among critically ill subjects. Biomarkers help to monitor the severity of neurological status. This study aimed to identify the best biomarker, along with APACHE II score, in mortality prediction among patients admitted to the ICU with the primary brain injury. This cohort study covered 58 patients. APACHE II scores were assessed 24 h post ICU admission. The concentrations of six biomarkers were determined, including the C-reactive protein (CRP), the S100 calcium-binding protein B (S100B), neuron-specific enolase (NSE), neutrophil gelatinase-associated lipocalin (NGAL), matrix metalloproteinase 9 (MMP-9), and tissue inhibitor of metalloproteinase 1 (TIMP-1), using commercially available ELISA kits. The biomarkers were specifically chosen for this study due to their established connection to the pathophysiology of brain injury. In-hospital mortality was the outcome. Median APACHE II was 18 (IQR 13–22). Mortality reached 40%. Median concentrations of the CRP, NGAL, S100B, and NSE were significantly higher in deceased patients. S100B (AUC = 0.854), NGAL (AUC = 0.833), NSE (AUC = 0.777), and APACHE II (AUC = 0.766) were the best independent predictors of mortality. Combination of APACHE II with S100B, NSE, NGAL, and CRP increased the diagnostic accuracy of mortality prediction. MMP and TIMP-1 were impractical in prognostication, even after adjustment for APACHE II score. S100B protein and NSE seem to be the best predictors of compromised outcome among critically ill patients with primary brain injuries and should be assessed along with the APACHE II calculation after ICU admission.

Diagnostic Value of Serum Biomarkers for Differentiating Central and Peripheral Causes of Acute Vertigo

Background: In patients presenting with acute vertigo or dizziness, distinguishing central from peripheral is a diagnostic challenge. This study investigated potential serum markers for differentiating central and peripheral vertigo in patients with acute-onset vertigo.

Methods: This prospective case–control study recruited consecutive participants from the Emergency Department, including patients with acute-onset vertigo or dizziness within 12 h and control subjects. We used enzyme-linked immunosorbent assays to measure the serum S100β, NSE, BDNF, GFAP, and IL-6 levels during the acute period.

Results: The 114 study subjects included 28 patients with central vertigo (CV), 49 patients with peripheral vertigo (PV), and 37 age- and sex-matched healthy controls. No differences were found in risk factor distribution among the three groups. In patients with CV, the serum NSE and S100β levels were significantly (p < 0.05) elevated compared with the control and PV groups. The ROC analysis gave an AUC of 0.843 (95% CI = 0.753–0.932) for NSE and 0.787 (95% CI = 0.687–0.886) for S100β for predicting CV. However, there were no significant differences in the serum GFAP and BDNF levels among the CV, PV, and control groups.

Conclusions: Serum NSE and S100β levels are significantly higher in patients with CV, such as occurs with posterior circulation ischemic stroke or vertebrobasilar insufficiency. S100β and NSE may serve as serum biomarkers for differentiating between CV and PV in patients with acute-onset vertigo.

Prognostic Abilities of Serial Neuron-Specific Enolase and Lactate and their Combination in Cardiac Arrest Survivors During Targeted Temperature Management

This study aimed to determine the prognostic ability of serial neuron-specific enolase (NSE) and lactate in cardiac arrest survivors treated with targeted temperature management (TTM) and to investigate whether a combination of NSE and lactate could increase prognostic information. This observational, retrospective, cohort study was conducted between January 2013 and December 2018; data were extracted from an out-of-hospital cardiac arrest registry. We collected serial serum NSE and lactate levels during TTM. The primary endpoint was poor neurological outcome at 28 days from cardiac arrest. Of all 160 included patients, 98 (61.3%) had poor neurological outcomes. Areas under the curves (AUCs) for NSE were 0.797, 0.871, and 0.843 at 24, 48, and 72 h, respectively (all p < 0.05). AUCs for lactate were 0.669, 0.578, 0.634, and 0.620 at 0, 24, 48, and 72 h, respectively (all p < 0.05). Although the combination of initial lactate and NSE at 48 h yielded the highest discovered AUC (0.877) it was not statistically different from that for the 48 h NSE alone (p = 0.692). During the TTM, NSE at 48 h from cardiac arrest was the most robust prognostic marker in comatose cardiac arrest survivors. However, a combination of the 48 h NSE with lactate did not increase the prognostic information.

Hypothermia Inhibits Cerebral Necroptosis and NOD-Like Receptor Pyrin Domain Containing 3 Pathway in a Swine Model of Cardiac Arrest

BACKGROUND

Targeted temperature management (TTM) is commonly used in hypothermia after cardiopulmonary resuscitation (CPR), and its mechanism to improve cerebral function is complex. This study aimed to investigate the effects of TTM on necroptosis and the NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasome in the brain tissue of pigs after CPR.

MATERIALS AND METHODS

Ventricular fibrillation was induced, and CPR was performed 10 min later in nine pigs in the normothermia group and nine pigs in the TTM group. The body temperature in the TTM group was dropped to 33°C after CPR and maintained for 24 h, whereas in the normothermia group, it was maintained at 38°C. Before CPR and at 30 h after CPR, serum neuron-specific enolase and S-100β were measured. At 30 h after CPR, pigs were euthanized, and brain tissues were collected for measurement of receptor-interacting protein kinase (RIPIK) 1, RIPK3, mixed lineage kinase domain-like (MLKL), NLRP3, cysteinyl aspartate-specific proteinase (caspase)-1, interleukin (IL)-1β, and IL-18.

RESULTS

Serum neuron-specific enolase and S-100β were increased significantly (P < 0.05) in the two CPR-treated groups compared with the sham group and more obviously in the normothermia group. In addition, the expression of RIPK3, phosphorylated MLKL, and NLRP3 in brain tissues was increased. The expression of RIPK3, phosphorylated MLKL, NLRP3, and caspase-1 as well as the levels of IL-1β and IL-18 were lower (P < 0.05) in the TTM group compared with the normothermia group.

CONCLUSIONS

Necroptosis and the NLRP3 pathway were activated after CPR. TTM may attenuate postresuscitation brain injury through the regulation of necroptosis and the NLRP3 pathway.

Change in neuron specific enolase levels in out-of-hospital cardiopulmonary arrest survivors as a simple and useful tool to predict neurological prognosis

INTRODUCTION AND OBJECTIVES

Neuron-specific enolase (NSE) is a prognostic marker in out-of-hospital cardiopulmonary arrest (OHCA) survivors treated with mild therapeutic hypothermia (MTH). The objectives were to analyze the correlation between dynamic changes in NSE and outcomes and to determine the measurement timing that best predicts neurological status.

METHODS

Multicenter cohort study including patients admitted after shockable rhythm OHCA and treated with MTH. Serum NSE was sampled at 2 different times and Δ-NSE (%) was calculated as 100 x (NSE2-NSE1)/NSE1. In-hospital mortality and neurological outcome, as assessed by the Cerebral Performance Category (CPC) scale, were evaluated during admission and after a 6-month follow-up.

RESULTS

We included 166 patients admitted to 4 hospitals. In-hospital mortality was 31.9%. Almost 60% of patients had a good neurological recovery (CPC 1-2). On univariate and multivariate logistic regression analyses, an increase in NSE levels was associated with higher in-hospital mortality and worse CPC on discharge and after 6-months (P<.001). Positive Δ-NSE showed an OR=9.28 (95% CI 4.40-19.57) for mortality, OR=11.23 (95% CI 5.24-24.11) for CPC 3-5 at discharge and OR=11.14 (95% CI 5.05-24.55) for CPC 3-5 after 6-months' follow-up (P<.001). The first NSE measurement, conducted at 18 to 24hours, and the second measurement at 69 to 77hours after OHCA showed a high area under the curve in predicting CPC at discharge (0.9389 and 0.9909, respectively; 0.8096 for the whole cohort).

CONCLUSIONS

Dynamic changes in NSE serum levels are good markers of hard clinical outcomes after an OHCA due to shockable rhythm in an MTH-treated cohort. NSE measurements at specific intervals after OHCA may predict events even more precisely.

Combination of S100B and procalcitonin improves prognostic performance compared to either alone in patients with cardiac arrest: A prospective observational study

This study aimed to determine whether the combination of procalcitonin (PCT) and S100B improves prognostic performance compared to either alone in cardiac arrest (CA) patients treated with targeted temperature management (TTM).We performed a prospective cohort study of CA patients treated with TTM. PCT and S100B levels were obtained at 0, 24, 48, and 72 hours after return of spontaneous circulation. The prognostic performance was analyzed using each marker and the combination of the 2 markers for predicting poor neurological outcome at 3 months and mortality at 14 days and 3 months.A total of 97 patients were enrolled, of which 67 (69.1%) had poor neurological outcome. S100B showed a better prognostic performance (area under the curve [AUC], 0.934; sensitivity, 77.6%; and specificity, 100%) than PCT (AUC, 0.861; sensitivity, 70.2%; and specificity, 83.3%) with the highest prognostic value at 24 hours. The combination of 24-hour PCT and S100B values (S100B ≥0.2 μg/L or PCT ≥6.6 ng/mL) improved sensitivity (85.07%) compared with S100B alone. In multivariate analysis, PCT was associated with mortality at 14 days (odds ratio [OR]: 1.064, 95% confidence interval [CI]: 1.014-1.118), whereas S100B was associated with neurological outcomes at 3 months (OR: 9.849, 95% CI: 2.089-46.431).The combination of PCT and S100B improved prognostic performance compared to the use of either biomarker alone in CA patient treated with TTM. Further studies that will identify the optimal cutoff values for these biomarkers must be conducted.

[In-hospital outcomes of carotid endarterectomy depending on severity of contralateral lesion]

AIM

To compare in-hospital outcomes of carotid endarterectomy (CEE) in patients with different lesion of contralateral internal carotid artery (ICA).

MATERIAL AND METHODS

There were 730 CEE procedures in patients with bilateral ICA lesion for the period 2011-2016. All patients were divided into 4 groups depending on contralateral ICA stenosis grade: group 1 - stenosis up to 60% (42.6%, n=311); group 2 - 60-90% (18.7%, n=137); group 3 - 90-99% (25.9%, n=189); group 4 - occlusion (12.7%, n=93). Endpoints were unfavorable cardiovascular events including death, myocardial infarction (MI), stroke/TIA, significant hemorrhage by BARC scale (Bleeding Academic Research Consortium).

RESULTS

In-hospital mortality and incidence of MI, stroke/TIA were similar in all groups. However, there were no cardiovascular complications in patients with critical contralateral stenosis or occlusion. Bleeding followed by redo surgery was the most frequent complication. Overall incidence of adverse cardiovascular events did not exceed 1.23%.

CONCLUSION

There was no correlation between contralateral ICA stenosis and incidence of in-hospital adverse events including death, MI, stroke/TIA. Currently, technique of CEE is well developed that is associated with low incidence of postoperative complications.

Targeting two different levels of both arterial carbon dioxide and arterial oxygen after cardiac arrest and resuscitation: a randomised pilot trial

Purpose

We assessed the effects of targeting low-normal or high-normal arterial carbon dioxide tension (PaCO₂) and normoxia or moderate hyperoxia after out-of-hospital cardiac arrest (OHCA) on markers of cerebral and cardiac injury.

Methods

Using a 2³ factorial design, we randomly assigned 123 patients resuscitated from OHCA to low-normal (4.5–4.7 kPa) or high-normal (5.8–6.0 kPa) PaCO₂ and to normoxia (arterial oxygen tension [PaO₂] 10–15 kPa) or moderate hyperoxia (PaO₂ 20–25 kPa) and to low-normal or high-normal mean arterial pressure during the first 36 h in the intensive care unit. Here we report the results of the low-normal vs. high-normal PaCO₂ and normoxia vs. moderate hyperoxia comparisons. The primary endpoint was the serum concentration of neuron-specific enolase (NSE) 48 h after cardiac arrest. Secondary endpoints included S100B protein and cardiac troponin concentrations, continuous electroencephalography (EEG) and near-infrared spectroscopy (NIRS) results and neurologic outcome at 6 months.

Results

In total 120 patients were included in the analyses. There was a clear separation in PaCO₂ (p < 0.001) and PaO₂ (p < 0.001) between the groups. The median (interquartile range) NSE concentration at 48 h was 18.8 µg/l (13.9–28.3 µg/l) in the low-normal PaCO₂ group and 22.5 µg/l (14.2–34.9 µg/l) in the high-normal PaCO₂ group, p = 0.400; and 22.3 µg/l (14.8–27.8 µg/l) in the normoxia group and 20.6 µg/l (14.2–34.9 µg/l) in the moderate hyperoxia group, p = 0.594). High-normal PaCO₂ and moderate hyperoxia increased NIRS values. There were no differences in other secondary outcomes.

Conclusions

Both high-normal PaCO₂ and moderate hyperoxia increased NIRS values, but the NSE concentration was unaffected.

Registration

ClinicalTrials.gov, NCT02698917. Registered on January 26, 2016.

Electronic supplementary material

The online version of this article (10.1007/s00134-018-5453-9) contains supplementary material, which is available to authorized users.

Neurologic and cognitive outcomes associated with the clinical use of xenon: a systematic review and meta-analysis of randomized-controlled trials

BACKGROUND

Xenon has been shown to have positive neurologic effects in various pre-clinical models. This study systematically reviewed the randomized-controlled trials (RCTs) investigating neurologic and cognitive outcomes associated with the clinical use of xenon.

METHODS

We searched PubMed, CENTRAL, EMBASE, CINAHL, elibrary.ru (for Russian studies), Google Scholar (for Russian studies), and Wanfang (for Chinese studies) for appropriate RCTs comparing neurologic or cognitive outcomes after clinical use of xenon with control treatment or with other anesthetic agents.

RESULTS

Seventeen RCTs met the inclusion criteria. Two studies investigated the effects of xenon plus therapeutic hypothermia to treat neonatal asphyxia or out-of-hospital cardiac arrest. Compared with therapeutic hypothermia alone, xenon and therapeutic hypothermia reduced cerebral white matter abnormalities after cardiac arrest but had no effect on neurocognitive outcome and mortality. Xenon had no added value when used to treat neonatal asphyxia. Thirteen RCTs compared neurocognitive effects of xenon with other anesthetic agents in surgical patients. While xenon may be associated with improved short-term (< three hours) cognitive outcome, no medium-term (six hours to three months) advantage was observed, and longer-term data are lacking. No differences in biochemical (S-100β, neuron-specific enolase) and neuropsychologic (attentional performance) outcomes were found with xenon compared with other anesthetic drugs. Finally, two studies suggest that brief, intermittent administration of sub-anesthetic doses of xenon to patients during the acute phase of substance withdrawal may improve neurocognitive outcomes.

CONCLUSIONS

Despite promising pre-clinical results, the evidence for positive clinical neurologic and cognitive outcomes associated with xenon administration is modest. Nevertheless, there is some evidence to suggest that xenon may be associated with better neurologic outcomes compared with the standard of care therapy in certain specific clinical situations. More clinical trials are needed to determine any potential benefit linked to xenon administration.

Combining early post-resuscitation EEG and HRV features improves the prognostic performance in cardiac arrest model of rats

OBJECTIVE

Early and reliable prediction of neurological outcome remains a challenge for comatose survivors of cardiac arrest (CA). The purpose of this study was to evaluate the predictive ability of EEG, heart rate variability (HRV) features and the combination of them for outcome prognostication in CA model of rats.

METHODS

Forty-eight male Sprague-Dawley rats were randomized into 6 groups (n=8 each) with different cause and duration of untreated arrest. Cardiopulmonary resuscitation was initiated after 5, 6 and 7min of ventricular fibrillation or 4, 6 and 8min of asphyxia. EEG and ECG were continuously recorded for 4h under normothermia after resuscitation. The relationships between features of early post-resuscitation EEG, HRV and 96-hour outcome were investigated. Prognostic performances were evaluated using the area under receiver operating characteristic curve (AUC).

RESULTS

All of the animals were successfully resuscitated and 27 of them survived to 96h. Weighted-permutation entropy (WPE) and normalized high frequency (nHF) outperformed other EEG and HRV features for the prediction of survival. The AUC of WPE was markedly higher than that of nHF (0.892 vs. 0.759, p<0.001). The AUC was 0.954 when WPE and nHF were combined using a logistic regression model, which was significantly higher than the individual EEG (p=0.018) and HRV (p<0.001) features.

CONCLUSIONS

Earlier post-resuscitation HRV provided prognostic information complementary to quantitative EEG in the CA model of rats. The combination of EEG and HRV features leads to improving performance of outcome prognostication compared to either EEG or HRV based features alone.

Prognostic Value of S-100β Protein for Prediction of Post-Concussion Symptoms after a Mild Traumatic Brain Injury: Systematic Review and Meta-Analysis

This systematic review and meta-analysis aimed to determine the prognostic value of S-100β protein to identify patients with post-concussion symptoms after a mild traumatic brain injury (mTBI). A search strategy was submitted to seven databases from their inception to October 2016. Individual patient data were requested. Cohort studies evaluating the association between S-100β protein level and post-concussion symptoms assessed at least seven days after the mTBI were considered. Outcomes were dichotomized as persistent (≥3 months) or early (≥7 days <3 months). Our search strategy yielded 23,298 citations of which 29 studies including between seven and 223 patients (n = 2505) were included. Post-concussion syndrome (PCS) (16 studies) and neuropsychological symptoms (9 studies) were the most frequently assessed outcomes. The odds of having persistent PCS (odds ratio [OR] 0.62, 95% confidence interval [CI]: 0.34-1.12, p = 0.11, I² 0% [n = five studies]) in patients with an elevated S-100β protein serum level were not significantly different from those of patients with normal values while the odds of having early PCS (OR 1.67, 95% CI: 0.98-2.85, p = 0.06, I² 38% [n = five studies]) were close to statistical significance. Similarly, having an elevated S-100β protein serum level was not associated with the odds of returning to work at six months (OR 2.31, 95% CI: 0.50-10.64, p = 0.28, I² 22% [n = two studies]). Overall risk of bias was considered moderate. Results suggest that the prognostic biomarker S-100β protein has a low clinical value to identify patients at risk of persistent post-concussion symptoms. Variability in injury to S-100ß protein sample time, mTBI populations, and outcomes assessed could potentially explain the lack of association and needs further evaluation.

Targeting low- or high-normal Carbon dioxide, Oxygen, and Mean arterial pressure After Cardiac Arrest and REsuscitation: study protocol for a randomized pilot trial

Background

Arterial carbon dioxide tension (PaCO₂), oxygen tension (PaO₂), and mean arterial pressure (MAP) are modifiable factors that affect cerebral blood flow (CBF), cerebral oxygen delivery, and potentially the course of brain injury after cardiac arrest. No evidence regarding optimal treatment targets exists.

Methods

The Carbon dioxide, Oxygen, and Mean arterial pressure After Cardiac Arrest and REsuscitation (COMACARE) trial is a pilot multi-center randomized controlled trial (RCT) assessing the feasibility of targeting low- or high-normal PaCO₂, PaO₂, and MAP in comatose, mechanically ventilated patients after out-of-hospital cardiac arrest (OHCA), as well as its effect on brain injury markers. Using a 2³ factorial design, participants are randomized upon admission to an intensive care unit into one of eight groups with various combinations of PaCO₂, PaO₂, and MAP target levels for 36 h after admission.

The primary outcome is neuron-specific enolase (NSE) serum concentration at 48 h after cardiac arrest. The main feasibility outcome is the between-group differences in PaCO2, PaO2, and MAP during the 36 h after ICU admission. Secondary outcomes include serum concentrations of NSE, S100 protein, and cardiac troponin at 24, 48, and 72 h after cardiac arrest; cerebral oxygenation, measured with near-infrared spectroscopy (NIRS); potential differences in epileptic activity, monitored via continuous electroencephalogram (EEG); and neurological outcomes at six months after cardiac arrest.

Discussion

The trial began in March 2016 and participant recruitment has begun in all seven study sites as of March 2017. Currently, 115 of the total of 120 patients have been included. When completed, the results of this trial will provide preliminary clinical evidence regarding the feasibility of targeting low- or high-normal PaCO₂, PaO₂, and MAP values and its effect on developing brain injury, brain oxygenation, and epileptic seizures after cardiac arrest. The results of this trial will be used to evaluate whether a larger RCT on this subject is justified.

Trial registration

ClinicalTrials.gov, NCT02698917. Registered on 26 January 2016.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-017-2257-0) contains supplementary material, which is available to authorized users.

Four-year experience of providing mobile extracorporeal life support to out-of-center patients within a suprainstitutional network-Outcome of 160 consecutively treated patients

AIM

Mobile extracorporeal life support (ECLS) may soon be on the verge to become a fundamental part of emergency medicine. Here, we report on our four-year experience of providing advanced mechanical circulatory support for out-of-center patients within the Düsseldorf ECLS Network (DELSN).

METHODS

This retrospective cohort study analyses the outcome of 160 patients with refractory circulatory failure consecutively treated with mobile veno-arterial extracorporeal membrane oxygenation (vaECMO) between July 2011 and October 2015 within the DELSN.

RESULTS

Out of the 160 patients (56±16years, vaECMO initiation under CPR 68%), 59 patients (36%) survived to primary discharge, with 50 patients (31%) still alive after a median follow-up of 1.74 years. Time-discrete mortality was highest during the first 24h. There was no difference between survivors and non-survivors regarding age, etiology of circulatory failure, presence of CPR during implantation or distance to implantation site. Incidence of kidney injury requiring dialysis (61% vs. 24%, p<0.0001), shock liver (27% vs. 12%, p=0.031) and visceral ischemia (19% vs. 3%, p=0.013) were the only complications increased in non-survivors. Subgroup analysis showed no significant outcome difference for ECPR vs. non-ECPR patients. Outcome was significantly impaired with initial neuron-specific enolase ≥45.4μg/L (AUC 0.75, p<0.0001) and lactate ≥5.5mmol/L (AUC 0.70, p<0.0001). Program-year-dependent in-center mortality showed an increasing trend, while program-year-dependent follow-up mortality decreased over time.

CONCLUSIONS

This study illustrates that regional mobile ECLS rescue therapy can be provided with encouraging outcomes, although patient selection criteria and early outcome parameters reflecting on therapy success or futility still need to be refined.

The role of stump pressure and cerebral oximetry in predicting ischaemic brain damage during carotid endarterectomy

Objective is to compare the predictive value of stump pressure (SP) and cerebral oximetry (rSO2) levels in the evaluation of ischaemic injury of the cerebrum during clamping of the carotid artery (CCA) without temporary shunt (TS). Methods We included 84 patients with an asymptomatic stenosis (>70%) of the internal carotid artery (ICA) who underwent carotid endarterectomy (CEA) under GA. Cerebral ischaemic tolerance (CIT) was determined on the basis of SP, rSO2 and ∆rSO2 (↓rSO2 from baseline) during CCA. The levels of S100 protein (S100) and neuron-specific enolase (NSE) were measured on each stage of the study. MRI was performed for all patients. Results There were no perioperative strokes and myocardial infarctions during the study. Temporary shutdown of blood flow in CAs during CEA is accompanied by a significant elevation of S100, NSE concentration with their subsequent restoration (three days after surgery). ROC analysis showed that none of the methods for CIT assessment (SP, rSO2 and ∆rSO2) was a valuable predictor of cerebral damage during CEA. Conclusion SP with a threshold value of ≤40 mmHg has an average quality of prediction (AUC = 63). ∆rSO2 of ≥20% and a threshold value of rSO2 ≤ 40% have an unsatisfactory quality of prediction (AUC < 60).

Association of neuron-specific enolase values with outcomes in cardiac arrest survivors is dependent on the time of sample collection

Background

Despite marked advances in intensive cardiology care, current options for outcome prediction in cardiac arrest survivors remain significantly limited. The aim of our study was, therefore, to compare the day-specific association of neuron-specific enolase (NSE) with outcomes in out-of-hospital cardiac arrest (OHCA) survivors treated with hypothermia.

Methods

Eligible patients were OHCA survivors treated with targeted temperature management at 33 °C for 24 h using an endovascular device. Blood samples for NSE levels measurement were drawn on days 1, 2, 3, and 4 after hospital admission. Thirty-day neurological outcomes according to the Cerebral Performance Category (CPC) scale and 12-month mortality were evaluated as clinical end points.

Results

A total of 153 cardiac arrest survivors (mean age 64.2 years) were enrolled in the present study. Using ROC analysis, optimal cutoff values of NSE for prediction of CPC 3–5 score on specific days were determined as: day 1 > 20.4 mcg/L (sensitivity 63.3%; specificity 82.1%; P = 0.002); day 2 > 29.0 mcg/L (72.5%; 94.4%; P < 0.001); and day 3 > 20.7 mcg/L (94.4%; 86.7%; P < 0.001). The highest predictive value, however, was observed on day 4 > 19.4 mcg/L (93.5%; 91.0%; P < 0.001); NSE value >50.2 mcg/L at day 4 was associated with poor outcome with 100% specificity and 42% sensitivity. Moreover, NSE levels measured on all individual days also predicted 12-month mortality (P < 0.001); the highest predictive value for death was observed on day 3 > 18.1 mcg/L (85.3%; 72.0%; P < 0.001). Significant association with prognosis was found also for changes in NSE at different time points. An NSE level on day 4 > 20.0 mcg/L, together with a change > 0.0 mcg/L from day 3 to day 4, predicted poor outcome (CPC 3–5) with 100% specificity and 73% sensitivity.

Conclusions

Our results suggest that NSE levels are a useful tool for predicting 30-day neurological outcome and long-term mortality in OHCA survivors treated with targeted temperature management at 33 °C. The highest associations of NSE with outcomes were observed on day 4 and day 3 after cardiac arrest.

Serial Sampling of Serum Protein Biomarkers for Monitoring Human Traumatic Brain Injury Dynamics: A Systematic Review

BACKGROUND

The proteins S100B, neuron-specific enolase (NSE), glial fibrillary acidic protein (GFAP), ubiquitin carboxy-terminal hydrolase L1 (UCH-L1), and neurofilament light (NF-L) have been serially sampled in serum of patients suffering from traumatic brain injury (TBI) in order to assess injury severity and tissue fate. We review the current literature of serum level dynamics of these proteins following TBI and used the term "effective half-life" (t1/2) in order to describe the "fall" rate in serum.

MATERIALS AND METHODS

Through searches on EMBASE, Medline, and Scopus, we looked for articles where these proteins had been serially sampled in serum in human TBI. We excluded animal studies, studies with only one presented sample and studies without neuroradiological examinations.

RESULTS

Following screening (10,389 papers), n = 122 papers were included. The proteins S100B (n = 66) and NSE (n = 27) were the two most frequent biomarkers that were serially sampled. For S100B in severe TBI, a majority of studies indicate a t1/2 of about 24 h, even if very early sampling in these patients reveals rapid decreases (1-2 h) though possibly of non-cerebral origin. In contrast, the t1/2 for NSE is comparably longer, ranging from 48 to 72 h in severe TBI cases. The protein GFAP (n = 18) appears to have t1/2 of about 24-48 h in severe TBI. The protein UCH-L1 (n = 9) presents a t1/2 around 7 h in mild TBI and about 10 h in severe. Frequent sampling of these proteins revealed different trajectories with persisting high serum levels, or secondary peaks, in patients with unfavorable outcome or in patients developing secondary detrimental events. Finally, NF-L (n = 2) only increased in the few studies available, suggesting a serum availability of >10 days. To date, automated assays are available for S100B and NSE making them faster and more practical to use.

CONCLUSION

Serial sampling of brain-specific proteins in serum reveals different temporal trajectories that should be acknowledged. Proteins with shorter serum availability, like S100B, may be superior to proteins such as NF-L in detection of secondary harmful events when monitoring patients with TBI.

Prognostic utility of neuroinjury biomarkers in post out-of-hospital cardiac arrest (OHCA) patient management

Despite aggressive intervention, patients who survive an out-of-hospital cardiac arrest (OHCA) generally have very poor prognoses, with nationwide survival rates of approximately 10-20%. Approximately 90% of survivors will have moderate to severe neurological injury ranging from moderate cognitive impairment to brain death. Currently, few early prognostic indicators are considered reliable enough to support patients' families and clinicians' in their decisions regarding medical futility. Blood biomarkers of neurological injury after OHCA may be of prognostic value in these cases. When most bodily tissues are oxygen-deprived, cellular metabolism switches from aerobic to anaerobic respiration. Neurons are a notable exception, however, being dependent solely upon aerobic respiration. Thus, after several minutes without circulating oxygen, neurons sustain irreversible damage, and certain measurable biomarkers are released into the circulation. Prior studies have demonstrated value in blood biomarkers in prediction of survival and neurologic impairment after OHCA. We hypothesize that understanding peptide biomarker kinetics in the early return of spontaneous circulation (ROSC) period, especially in the setting of refractory cardiac arrest, may assist clinicians in determining prognosis earlier in acute resuscitation. Specifically, during and after immediate resuscitation and return of ROSC, clinicians and families face a series of important questions regarding patient prognosis, futility of care and allocation of scarce resources such as the early initiation of extracorporeal cardiopulmonary resuscitation (ECPR). The ability to provide early prognostic information in this setting is highly valuable. Currently available, as well as potential biomarkers that could be good candidates in prognostication of neurological outcomes after OHCA or in the setting of refractory cardiac arrest will be reviewed and discussed.

Predictive value of neuron-specific enolase for prognosis in patients with moderate or severe traumatic brain injury: a systematic review and meta-analysis

BACKGROUND

Prognosis is difficult to establish early after moderate or severe traumatic brain injury despite representing an important concern for patients, families and medical teams. Biomarkers, such as neuron-specific enolase, have been proposed as potential early prognostic indicators. Our objective was to determine the association between neuron-specific enolase and clinical outcomes, and the prognostic value of neuron-specific enolase after a moderate or severe traumatic brain injury.

METHODS

We searched MEDLINE, Embase, The Cochrane Library and Biosis Previews, and reviewed reference lists of eligible articles to identify studies. We included cohort studies and randomized controlled trials that evaluated the prognostic value of neuron-specific enolase to predict mortality or Glasgow Outcome Scale score in patients with moderate or severe traumatic brain injury. Two reviewers independently collected data. The pooled mean differences were analyzed using random-effects models. We assessed risk of bias using a customized Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. Subgroup and sensitivity analyses were performed based on a priori hypotheses.

RESULTS

We screened 5026 citations from which 30 studies (involving 1321 participants) met our eligibility criteria. We found a significant positive association between neuron-specific enolase serum levels and mortality (10 studies, n = 474; mean difference [MD] 18.46 µg/L, 95% confidence interval [CI] 10.81 to 26.11 µg/L; I2 = 83%) and a Glasgow Outcome Scale ≤ 3 (14 studies, n = 603; MD 17.25 µg/L, 95% CI 11.42 to 23.07 µg/L; I2 = 82%). We were unable to determine a clinical threshold value using the available patient data.

INTERPRETATION

In patients with moderate or severe traumatic brain injury, increased neuron-specific enolase serum levels are associated with unfavourable outcomes. The optimal neuron-specific enolase threshold value to predict unfavourable prognosis remains unknown and clinical decision-making is currently not recommended until additional studies are made available.

Use of S-100B, NSE, CRP and ESR to predict neurological outcomes in patients with return of spontaneous circulation and treated with hypothermia

BACKGROUND

With the introduction of therapeutic hypothermia (TH), the prediction of neurological outcomes in cardiac arrest (CA) survivors is challenging. Early, accurate determination of prognosis by emergency physicians is important to avoid unnecessarily prolonged critical care with a likely poor neurological outcome.

METHODS

This prospective observational study included patients with non-traumatic CA and return of spontaneous circulation (ROSC) between March 2009 and May 2012 at a tertiary academic hospital. Unconscious patients with ROSC were treated with mild TH (32°C-34°C) for 24 hours. Blood samples were collected for S-100B, neuron-specific enolase (NSE), C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) at 0, 24 and 48 hours post-ROSC. Neurological outcomes were evaluated at hospital discharge and dichotomised as good (cerebral performance category (CPC) 1 or 2) or poor (CPC 3, 4 or 5).

RESULTS

Of the 119 patients (68.1% male, 53±15.6 years old) who underwent TH, 46 patients had a good outcome (38.9%). Poor neurological outcomes were predicted using receiver operating characteristic analyses at cut-off values of 0.12 g/L for S-100B at 24 hours post-ROSC (sensitivity, 95.0%; specificity, 75.6%; area under the curve (AUC) 0.916; 95% CI of AUC: 0.846 to 0.961), 31.03 ng/mL for NSE at 48 hours post-ROSC (sensitivity, 83.9%; specificity, 96.9%; AUC 0.929; 95% CI of AUC: 0.836 to 0.979) and 11.2 mg/dL for CRP at 48 hours post-ROSC (sensitivity, 69.4%; specificity, 75.0%; AUC 0.731; 95% CI of AUC: 0.617 to 0.827). ESR was not significant.

CONCLUSIONS

Among the biomarkers, S-100B at 24 hours and NSE at 48 hours post-ROSC were highly predictive of neurological outcomes in patients treated with TH after CA.

Serum proteomics as a strategy to identify novel biomarkers of neurologic recovery after cardiac arrest: a feasibility study

BACKGROUND

Serum biomarkers may play a role in prognostication after cardiac arrest. This study was designed to assess the feasibility of using two-dimensional gel electrophoresis (2D-GE) coupled with mass spectrometry (MS) as a proteomic strategy to identify novel biomarkers that may predict neurological recovery.

METHODS

Adult comatose survivors of ventricular fibrillation or pulseless ventricular tachycardia were considered eligible. Blood was collected and serum separated within 6 h of hospital admission and then at 24 h afterwards. Neurological outcome was assessed at 3 months with the Cerebral Performance Category (CPC) score. Serum was assessed with 2D-GE with and without prior depletion of high abundance proteins. Protein differences between patients with good (CPC 1,2) vs. poor (CPC 3-5) neurological recovery were subsequently identified with MS.

RESULTS

From August 2010 to June 2014, 11 patients meeting eligibility criteria were recruited, from which serum was available from 9 (5 with good neurological outcome). On non-depleted serum, only high abundance acute phase proteins such as haptoglobin, cell-free hemoglobin, albumin, and amyloid were detected in both patients with good and poor neurological recovery. Following depletion of high abundance proteins, proteins identified by MS in both patient populations were the acute phase reactants c-reactive protein and retinol binding protein-4. Proteins uniquely identified in the serum of patients with poor neurological recovery included 14-3-3 (epsilon and zeta isoforms) and muskelin.

CONCLUSIONS

Two-D-GE coupled with MS is a feasible strategy to facilitate the identification of novel predictive biomarkers. The presence of muskelin and 14-3-3 in the serum of patients with poor neurological prognosis warrants further investigation.

Serum S100B Protein as an Outcome Prediction Tool in Emergency Department Patients with Traumatic Brain Injury

OBJECTIVES

Traumatic brain injury is a common cause of death and disability worldwide. Early recognition of patients with brain cellular damage allows for early rehabilitation and patient outcome improvement.

METHODS

In this prospective study, the clinical conditions of patients with mild to moderate traumatic brain injury (TBI) were assessed, and patient serum S100B levels were measured. Patients were followed up one month later and evaluated for level of consciousness, presence or absence of post-traumatic headache, and daily activity performance (using the Barthel scale). Student's t-test and the chi-square test were used for data analysis, which was performed using SPSS software.

RESULTS

The mean serum S100B value was significantly lower for patients with minor TBI than for patients with moderate TBI (23.1±14.2 ng/dl and 134.0±245.0 ng/dl, respectively). Patients with normal CT scans also had statistically significantly lower serum S100B levels than patients with abnormal CT findings. The mean S100B value was statistically significantly higher for patients with suspected diffused axonal injury (632.18±516.1 ng/dl) than for patients with other abnormal CT findings (p=0.000): 24.97±22.9 ng/dl in patients with normal CT results; 41.56±25.7 ng/dl in patients with skull bone fracture; 57.38 ±28.9 ng/dl in patients with intracranial hemorrhage; and 76.23±38.3 ng/dl in patients with fracture plus intracranial hemorrhage).

CONCLUSIONS

Serum S100B levels increase in patients with minor to moderate TBIs, especially in those with diffused axonal injury. However, serum S100B values cannot accurately predict one-month neuropsychological outcomes and performance.

Serum neuron specific enolase could predict subclinical brain damage and the subsequent occurrence of brain related vascular events during follow up in essential hypertension

The object of this work was to explore if blood based biomarkers of brain damage could predict subclinical brain lesions and clinical outcome during follow-up in asymptomatic hypertensive patients. This was a cross-sectional study including 101 patients with essential hypertension and no clinical evidence of neurological disease and 53 healthy controls, followed by a longitudinal study of 62 hypertensive patients for an average of 33 months. Serum concentrations of two brain specific proteins (S100B and neuron specific enolase - NSE) were determined at inclusion. Fundoscopic exploration, brain MRI and echocardiographic studies were also performed. Clinical outcome at follow-up was registered: transient ischemic attack (TIA), stroke, vascular headache or migraine, cardiovascular events and death. Higher serum NSE and S100B concentrations were observed in hypertensive patients; and multiple regression analysis revealed independent associations of clinical variables and more severe white matter lesions only with NSE concentration. A panel combining two clinical variables (blood pressure>140/90 and years of hypertension>10) and serum NSE>13 μg/L predicted more severe white matter lesions with 80% sensitivity and 94.4% specificity. Higher NSE levels at inclusion were associated not only with the occurrence of vascular events related with the CNS (stroke, TIA and vascular headache), but also with an earlier presentation of these events during the follow-up period. Serum NSE concentration could be a useful biomarker to predict subclinical brain damage and future vascular events related with the CNS in hypertension. Blood based biomarkers could aid in filtering hypertensive patients with a higher risk of cerebrovascular disease for brain MRI scanning.

A pilot feasibility, safety and biological efficacy multicentre trial of therapeutic hypercapnia after cardiac arrest: study protocol for a randomized controlled trial

BACKGROUND

Cardiac arrest causes ischaemic brain injury. Arterial carbon dioxide tension (PaCO2) is a major determinant of cerebral blood flow. Thus, mild hypercapnia in the 24 h following cardiac arrest may increase cerebral blood flow and attenuate such injury. We describe the Carbon Control and Cardiac Arrest (CCC) trial.

METHODS/DESIGN

The CCC trial is a pilot multicentre feasibility, safety and biological efficacy randomized controlled trial recruiting adult cardiac arrest patients admitted to the intensive care unit after return of spontaneous circulation. At admission, using concealed allocation, participants are randomized to 24 h of either normocapnia (PaCO2 35 to 45 mmHg) or mild hypercapnia (PaCO2 50 to 55 mmHg). Key feasibility outcomes are recruitment rate and protocol compliance rate. The primary biological efficacy and biological safety measures are the between-groups difference in serum neuron-specific enolase and S100b protein levels at 24 h, 48 h and 72 h. Secondary outcome measure include adverse events, in-hospital mortality, and neurological assessment at 6 months.

DISCUSSION

The trial commenced in December 2012 and, when completed, will provide clinical evidence as to whether targeting mild hypercapnia for 24 h following intensive care unit admission for cardiac arrest patients is feasible and safe and whether it results in decreased concentrations of neurological injury biomarkers compared with normocapnia. Trial results will also be used to determine whether a phase IIb study powered for survival at 90 days is feasible and justified.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry ACTRN12612000690853 .

Biomarkers in septic encephalopathy: a systematic review of clinical studies

Objective

The aim of this study was to systematically review the importance of neuron-specific enolase and S100 beta for diagnosing and monitoring septic encephalopathy.

Methods

A PubMed database search was performed to identify studies that evaluated S100 beta and neuron-specific enolase serum levels in patients with sepsis and that were published between January 2000 and April 2012. Only human studies that employed an additional method of neurological assessment were selected.

Results

Nine studies were identified, seven of which associated high concentrations of S100 beta and neuron-specific enolase with the development of septic encephalopathy. Four studies also associated these concentrations with increased mortality. However, two studies did not find such an association when they evaluated S100 beta levels, and one of these studies did not observe a correlation between neuron-specific enolase and septic encephalopathy.

Conclusion

S100 beta and neuron-specific enolase are promising biomarkers for diagnosing and monitoring patients with septic encephalopathy, but more research is necessary.

MicroRNAs: new biomarkers and therapeutic targets after cardiac arrest?

Despite advances in resuscitation medicine, including target temperature management as part of post-cardiac arrest care, many patients will have a poor neurological outcome, most often resulting in death. It is a commonly held belief that the ability to prognosticate outcome at an early stage after cardiac arrest would allow subsequent health care delivery to be tailored to individual patients. However, currently available predictive methods and biomarkers lack sufficient accuracy and therefore cannot be generally recommended in clinical practice. MicroRNAs have recently emerged as potential biomarkers of cardiovascular diseases. While the biomarker value of microRNAs for myocardial infarction or heart failure has been extensively studied, less attention has been devoted to their prognostic value after cardiac arrest. This review highlights the recent discoveries suggesting that microRNAs may be useful both to predict outcome and to treat patients after cardiac arrest.

The Value of Serum NR2 Antibody in Prediction of Post-Cardiopulmonary Resuscitation Survival

INTRODUCTION

N-methyl-D-aspartate receptor subunits antibody (NR2-ab) is a sensitive marker of ischemic brain damage in clinical circumstances, such as cerebrovascular accidents. We aimed to assess the value of serum NR2-ab in predicting the post-cardiopulmonary resuscitation (CPR) survival.

METHODS

In this cohort study, we examined serum NR2-ab levels 1 hour after the return of spontaneous circulation (ROSC) in 49 successfully resuscitated patients. Patients with traumatic or asphyxic arrests, prior neurological insults, or major medical illnesses were excluded. Participants were followed until death or hospital discharge. Demographic data, coronary artery disease risk factors, time before initiation of CPR, and CPR duration were documented. In addition, Glasgow coma scale (GCS), blood pressure, and survival status of patients were recorded at 1, 6, 24, and 72 hour(s) after ROSC. Descriptive analyses were performed, and the Cox proportional hazard model was applied to assess if NR2-ab level is an independent predictive factor of survival.

RESULTS

49 successfully resuscitated patients were evaluated; 27 (55%) survived to hospital discharge, 4 (8.1%) were in vegetative state, 10 (20.4%) were physically disabled, and 13 (26.5%) were physically functional. Within 72 hours of ROSC all of the 12 NR2-ab positive patients died. In contrast, 31 (84%) of the NR2-ab negative patients survived. Sensitivity, specificity, positive and negative likelihood ratios of NR2-ab in prediction of survival were 54.5% (95%CI=32.7%-74.9%), 100% (95%CI=84.5%-100%), infinite, and 45.5% (95%CI=28.8%-71.8%), respectively. Subsequent analysis showed that both NR2-ab status and GCS were independent risk factors of death.

CONCLUSIONS

A positive NR2-ab serum test 1 hour after ROSC correlated with lower 72-hour survival. Further studies are required to validate this finding and demonstrate the value of a quantitative NR2-ab assay and its optimal time of measurement.

Continuous electroencephalogram patterns are suggestive of eventual neurologic outcomes in post-cardiac arrest patients treated with therapeutic hypothermia

INTRODUCTION

Therapeutic hypothermia (TH) after cardiac arrest (CA) resuscitation is the first therapy proven to increase survival to discharge and neurologic recovery. Methods for neurologic and mortality prognostication after CA resuscitation have been called into question because they were developed based on evidence that was developed prior to the advent of TH. This study examines the relationship between electroencephalogram (EEG) patterns and mortality and neurologic outcomes in post-CA patients undergoing TH.

METHODS

Eighty-three of 732 patients who had continuous EEG (cEEG) monitoring during TH were included. Continuous EEG tracings were classified as isoelectric, low voltage, burst suppression, epileptic form, and diffuse slowing. Primary outcomes are survival to discharge and Cerebral Performance Categories (CPCs) at hospital discharge.

RESULTS

Among patients with favorable neurologic outcomes (CPC1 and CPC2), the duration cardiopulmonary resuscitation and time until return of spontaneous circulation were shorter than observed in patients with poorer neurologic outcomes (CPC3, CPC4, and CPC5). The time to target temperature was equivalent among neurologic outcome groups (499.5 minutes vs 431.0 minutes, P = .09). Favorable neurologic outcome was associated with initial presentation with ventricular tachycardia or ventricular fibrillation and had cEEG patterns suggestive of diffuse slowing and epileptiform waves.

DISCUSSION

The use of cEEG can provide prognostication information otherwise not obtainable by clinical examination. Specific cEEG patterns predicted probability of mortality for patients according to their initial rhythm of CA as a function of cardiopulmonary resuscitation time.

Hypothermia after cardiac arrest does not affect serum levels of neuron-specific enolase and protein S-100b

BACKGROUND

We investigated the brain-derived proteins neuron-specific enolase (NSE) and protein S-100b (S-100b) in survivors of cardiac arrest who had either received therapeutic hypothermia (TH) or had not.

METHODS

In a retrospective cohort study, we analysed serum levels of these two proteins over 5 days in 201 adult cardiac arrest survivors admitted to our intensive care unit between 2003 and 2010. These were all survivors that remained comatose and survived at least 48 h. Of these, 140 received therapeutic hypothermia (hypothermia group). The remainder received only standard therapy without hypothermia (normothermia group).

RESULTS

There was no difference in survival between the hypothermia and normothermia groups. At 4 weeks after arrest, 61 (43.6%) patients of the hypothermia group and 26 (42.6%) patients of the normothermia group were still alive with favourable to moderate neurological outcome (Cerebral Performance Category Scale 1-3). We observed no change in the mean serum levels of either protein between the two groups. Within each group, we found significantly higher serum levels of NSE and S-100b in patients with unfavourable neurological outcome (Cerebral Performance Category Scale 4 and 5) than in those with moderate to favourable outcome. Cut-off levels 3 days after cardiac arrest predicting an unfavourable outcome were >40 ng/ml for NSE [specificity 95.2%, Sensitivity 74.1%, areas under the curve (AUC):0.889], false positive rate 4 [confidence interval (CI): 0.0131-0.1175] and >1.03 μg/1 for S-100b (specificity 95.6%, Sensitivity 57.8%, AUC: 0.875) false positive rate 3 (CI: 0.0091-01218).

CONCLUSIONS

Additional application of TH was not associated with significant changes in serum levels of NSE and S-100b in comatose survivors of cardiac arrest, compared to those treated without TH.

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.

The predictive value of soluble urokinase plasminogen activator receptor (SuPAR) regarding 90-day mortality and 12-month neurological outcome in critically ill patients after out-of-hospital cardiac arrest. Data from the prospective FINNRESUSCI study

AIM

The whole body ischaemia-reperfusion after cardiac arrest (CA) induces a systemic inflammation-reperfusion response. The expression of urokinase plasminogen activator receptor (uPAR) is known to be induced after hypoxia and increased levels of soluble form suPAR have been measured after hypoxia and ischaemia. Our aim was to evaluate, whether ischaemia/reperfusion injury after out-of-hospital cardiac arrest (OHCA) increases suPAR concentrations in serum and to evaluate the prognostic value of suPAR regarding 90-day mortality and 12-month neurological outcome.

METHODS

This is a pre-determined substudy of prospective FINNRESUSCI study. Total of 287 patients treated in the intensive care units after OHCA and with consent from the next-of-kin and serum samples between baseline and day 4 were included. Outcome and neurological outcome were evaluated according the Pittsburgh Cerebral Performance Categories (CPC). Kaplan-Meier survival curves, areas under receiver operational characteristics curves and positive likelihood ratios for mortality and poor neurological outcome were calculated.

RESULTS

Non-survivors had higher levels of suPAR after OHCA. Kaplan-Meier survival curves indicated high 90-day mortality in the highest concentration quintiles. LR+ for 1-year CPC 3-5 was 1.8-2.7 for the whole patient cohort and in shockable rhythms 2.0-2.4. In therapeutic hypothermia prognostic value remained.

CONCLUSIONS

We found that high SuPAR concentrations were associated with poor outcome in patients with OHCA admitted to critical care. However, suPAR alone had inadequate predictive value for poor outcome and did not associate with 12-month neurological outcome.

Complement activation and its prognostic role in post-cardiac arrest patients

Cardiac arrest causes generalized ischaemia/hypoxia, and subsequent resuscitation inflicts reperfusion injury, the pathology of which is not fully understood. Moreover, predicting the prognosis of comatose, post-cardiac arrest patients is a complex clinical challenge. We hypothesized that the extent of complement activation might be a reliable predictor of mortality in this population. Forty-six comatose cardiac arrest patients were enrolled into our prospective cohort study, conducted in a tertiary care university clinic. All subjects were cooled to 32-34 °C body temperature for 24 h and then allowed to rewarm to normothermia. All patients underwent diagnostic coronary angiography. On admission, at 6 and 24 h, blood samples were taken from the arterial catheter. In these, complement products (C3a, C3, C4d, C4, SC5b9 and Bb) were measured by ELISA in blood samples. Patients were followed up for 30 days; 22 patients (47.8%) died by the end of this period. We observed that complement activation (determined as the C3a to C3 ratio) was higher in non-survivors than in survivors at each time point. In the multivariate Cox regression analysis, the C3a/C3 ratio determined 24 h after the initiation of therapeutic hypothermia predicted 30-day mortality regardless of age, sex and the APACHE II score. Complement activation occurs in post-cardiac arrest patients, and its extent correlates with 30-day survival. The C3a/C3 ratio might prove useful for estimating the prognosis of comatose post-cardiac arrest patients.

Cortisol is an associated-risk factor of brain dysfunction in patients with severe sepsis and septic shock

Objectives. To investigate cortisol levels in brain dysfunction in patients with severe sepsis and septic shock. Methods. In 128 septic and sedated patients, we studied brain dysfunction including delirium and coma by the evaluation of Richmond Agitation Sedation Scale (RASS), the Confusion Method Assessment in the ICU (CAM-ICU) after sedation withdrawal and the measurement of serum S100B biomarker of brain injury. Serum cortisol and S100B were measured within 12 hours after ICU admission and daily over the next four days. Results. Brain dysfunction was observed in 50% (64/128) before but in 84% (107/128) of patients after sedation withdrawal, and was more common in the patients older than 57 years (P = 0.009). Both cortisol (P = 0.007) and S100B levels (P = 0.028) were higher in patients with than patients without brain dysfunction. Cortisol levels were associated with ICU mortality (hazard ratio = 1.17, P = 0.024). Multivariate logistic regression showed that cortisol (odds ratio (OR): 2.34, 95% CI (2.01, 3.22), P = 0.02) and the combination effect of cortisol with age (OR: 1.004, 95% CI (1.002, 1.93), P = 0.038) but not S100B were associated with brain dysfunction. Conclusions. Cortisol was an associated-risk factor of brain dysfunction in patients with severe sepsis and septic shock.

Biomarkers and acute brain injuries: interest and limits

For patients presenting with acute brain injury (such as traumatic brain injury, subarachnoid haemorrhage and stroke), the diagnosis and identification of intracerebral lesions and evaluation of the severity, prognosis and treatment efficacy can be challenging. The complexity and heterogeneity of lesions after brain injury are most probably responsible for this difficulty. Patients with apparently comparable brain lesions on imaging may have different neurological outcomes or responses to therapy. In recent years, plasmatic and cerebrospinal fluid biomarkers have emerged as possible tools to distinguish between the different pathophysiological processes. This review aims to summarise the plasmatic and cerebrospinal fluid biomarkers evaluated in subarachnoid haemorrhage, traumatic brain injury and stroke, and to clarify their related interests and limits for diagnosis and prognosis. For subarachnoid haemorrhage, particular interest has been focused on the biomarkers used to predict vasospasm and cerebral ischaemia. The efficacy of biomarkers in predicting the severity and outcome of traumatic brain injury has been stressed. The very early diagnostic performance of biomarkers and their ability to discriminate ischaemic from haemorrhagic stroke were studied.