S-100beta and neuron-specific enolase levels in carbon monoxide-related brain injury

A pilot study of neuroprotective effect of granulocyte colony-stimulating factor (G-CSF) in patients with carbon monoxide poisoning: a double-blind, randomized, placebo-controlled trial

Although neuroprotective effects of granulocyte colony-stimulating factor (G-CSF) have been shown in rats exposed to carbon monoxide (CO), this pilot clinical trial was performed to assess the feasibility of treatment with G-CSF in patients with acute CO poisoning. A double-blind, randomized, placebo-controlled pilot clinical trial was conducted on twenty-six patients with acute CO poisoning. G-CSF (90 μg/kg) was administered intravenously for 72 h. Demographic data, routine laboratory tests, differential blood counts, venous blood gas, and adverse reactions were recorded. The primary endpoint was brain ischemia improvement based on CT findings and the secondary endpoints examined improvements in the modified Rankin Scale (mRS), National Institutes of Health Stroke Scale (NIHSS), and Barthel Index as well as S-100β concentrations. Fourteen patients received G-CSF, and 12 received a placebo. Twenty-six were followed for 30 days and no one in both groups died during follow-up. Neurological complications, brain ischemic changes, Barthel, and mRS were compared between the two groups on determined days after the onset of therapeutic intervention, and no significant differences were observed between the two groups. Favorable results were achieved for treated patients by different measures; NIHSS was decreased 72 h after treatment (p = 0.046), and S-100β levels were significantly higher in the G-CSF group than in the control group, 12 h and 72 h after the treatment. G-CSF appears to have potential effects on several clinical parameters in patients with acute CO poisoning. The trial was registered at the Iranian Registry of Clinical Trials with the ID: (IRCT201607232083N7).

S2k guideline diagnosis and treatment of carbon monoxide poisoning

Carbon monoxide (CO) can occur in numerous situations and ambient conditions, such as fire smoke, indoor fireplaces, silos containing large quantities of wood pellets, engine exhaust fumes, and when using hookahs. Symptoms of CO poisoning are nonspecific and can range from dizziness, headache, and angina pectoris to unconsciousness and death. This guideline presents the current state of knowledge and national recommendations on the diagnosis and treatment of patients with CO poisoning. The diagnosis of CO poisoning is based on clinical symptoms and proven or probable exposure to CO. Negative carboxyhemoglobin (COHb) levels should not rule out CO poisoning if the history and symptoms are consistent with this phenomenon. Reduced oxygen-carrying capacity, impairment of the cellular respiratory chain, and immunomodulatory processes may result in myocardial and central nervous tissue damage even after a reduction in COHb. If CO poisoning is suspected, 100% oxygen breathing should be immediately initiated in the prehospital setting. Clinical symptoms do not correlate with COHb elimination from the blood; therefore, COHb monitoring alone is unsuitable for treatment management. Especially in the absence of improvement despite treatment, a reevaluation for other possible differential diagnoses ought to be performed. Evidence regarding the benefit of hyperbaric oxygen therapy (HBOT) is scant and the subject of controversy due to the heterogeneity of studies. If required, HBOT should be initiated within 6 h. All patients with CO poisoning should be informed about the risk of delayed neurological sequelae (DNS).

Serum NSE and S100B protein levels for evaluating the impaired consciousness in patients with acute carbon monoxide poisoning

The aim of this study was to investigate the associations between the levels of neuron-specific enolase (NSE) and S100B protein and coma duration, and evaluate the optimal cut-off values for prediction coma duration ≥ 72 hours in patients with acute carbon monoxide poisoning (ACOP).A total of 60 patients with ACOP were divided into 3 following groups according to their status of consciousness and coma duration at admission: Awake group [Glasgow Coma Scale score (GCS score) ≥ 13 points], Coma < 72 hours group (GCS score < 13 points and coma duration < 72 h), and Coma ≥ 72 hours group (GCS score < 13 points and coma duration ≥ 72 h). The levels of serum NSE and S100B protein were measured after admission.There were significant differences in GCS score, carbon monoxide (CO) exposure time, NSE, and S100B levels between the Coma ≥ 72 h group and the Awake group, and between the Coma < 72 h group and the Awake group. Significant differences in GCS score, NSE, and S100B levels were also found between Coma ≥ 72 h group and Coma < 72 h group. Correlation analysis showed that NSE and S100B were positively correlated (rs = 0.590, P < .01); NSE and S100B were negatively correlated with GCS score (rs = -0.583, rs = -0.590, respectively, both P < .01). The areas under the curve (AUCs) of NSE, S100B, and GCS score to predict the coma duration ≥ 72 hours were 0.754, 0.791, and 0.785, respectively. Pairwise comparisons did not show differences among the 3 groups (all P > .05). The sensitivity and specificity of NSE prediction with a cut-off value of 13 μg/L were 80% and 64%, respectively, and those of S100B prediction with a cut-off value of 0.43 μg/L were 70% and 88%, respectively.The NSE and S100B protein levels were significantly correlated with the degree of impaired consciousness and had the same clinical value in predicting coma duration of ≥ 72 hours in patients with ACOP.

Neuropsychiatric sequelae of acute carbon monoxide poisoning: The predictive role of neuron specific enolase and glial fibrillary acidic protein

BACKGROUND

Acute carbon monoxide (CO) poisoning is one of the most common poisons worldwide and neuropsychiatric sequelae (NS) are the most frequent form of its morbidity.

OBJECTIVES

This study aimed to measure the percentage of patients liable to NS, to evaluate the cognitive profile of patients with NS and to assess the role of neuron specific enolase (NSE) and glial fibrillary acidic protein (GFAP) in predicting the development of NS after acute CO poisoning.

METHODS

This prospective study included 50 patients with acute CO poisoning presented to the Poison Control Center, Ain Shams University Hospitals during the period from beginning of November 2015 till the end of January 2017. Patients' demographic characteristics, clinical manifestations and blood carboxyhemoglobin levels were recorded. Serum levels of NSE and GFAP were determined on admission. Every patient was invited to participate in a follow-up visit at a dedicated outpatient clinic one month after CO exposure. During the visit, a complete neurological examination, as well as a psychiatric evaluation using the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders version 4 Axis-I were performed for detection of neurological and psychiatric disorders. Wechsler memory scale test was administrated for detection of cognitive deficits. The patients were divided into two groups based on the presence or absence of NS.

RESULTS

Cognitive impairment was found in 38 % of patients in the NS group. The serum levels of NSE and GFAP were significantly high in the NS group in comparison to the non-NS group. Receiver operating characteristic curves (ROC) determined the cut-off level of NSE at 39 ng/mL achieved 100 % sensitivity with 88.64 % specificity to predict the development of NS after acute CO poisoning while GFAP had 95.24 % sensitivity and 69.23 % specificity at a cut-off value of 2.8 ng/mL.

CONCLUSION

NSE and GFAP could be useful in the early identification of patients at risk of developing NS after CO poisoning helping in treatment plans and thus improving quality of care.

Potential Role of Serum S-100β Protein as a Predictor of Cardiotoxicity and Clinical Poor Outcome in Acute Amphetamine Intoxication

Cardio- and neurotoxicity of amphetamines play an important role in worsening morbidity, making the initial evaluation of the patient's status a potentially lifesaving action. The current study hypothesized that the S-100β serum level could predict the severity of acute amphetamine toxicity and the in-hospital outcome. The current study is a prospective cohort study conducted on 77 patients diagnosed with acute amphetamine exposure and referred to Aseer Poison Control Center, Saudi Arabia. The patients admitted to ICU showed significantly higher serum levels of S-100β in comparison to those not admitted (p < 0.05). Moreover, the S-100β level was significantly elevated among patients with prolonged QTc intervals. Receiver-operating characteristic curve of S-100β serum level as an in-hospital outcome predictor showed that at a cutoff value > 0.430 ug/L, the sensitivity of S-100β serum level as severity predictor was 100%, and the specificity was 74.1%. In conclusion, the current study revealed that the S-100β serum level could be used as an outcome predictor in hospital admission cases due to toxic amphetamine exposure and offers an idea about the cardiac and neuronal involvement. This can help select patients who will benefit most from ICU admission and early management and assess the severity of cases in settings where GC-MS is not available.

Association between Neuron-Specific Enolase Gene Polymorphism and Delayed Encephalopathy after Acute Carbon Monoxide Poisoning

Objective

The aim of this study is to explore the relationship between neuron-specific enolase (NSE) gene polymorphism and delayed encephalopathy after acute carbon monoxide poisoning (DEACMP) and provide a theoretical basis for DEACMP pathogenesis, diagnosis, and prognosis.

Methods

To investigate this relationship, we screened 6 NSE single nucleotide polymorphisms (SNPs), based on the results of the previous genome-wide association studies (GWAS). A total of 1,201 patients, including 416 in the DEACMP group and 785 in the acute carbon monoxide poisoning (ACMP) group, were detected by the Sequenom MassARRAY® method. The genotype frequencies and alleles of the 6 NSE SNPs (rs2071074, rs2071417, rs2071419, rs11064464, rs11064465, and rs3213434) were compared using different genetic models.

Results

In the SNPs rs2071419 and rs3213434, we found that the genotypes and allele frequencies in the two groups significantly correlated with the grouping of patients (χ ² = 6.596, p = 0.037; χ ² = 8.769, p = 0.012). The haplotypes GGTTTC and CCTTTC of ACMP and DEACMP were different (χ ² = 6.563, p = 0.010; χ ² = 4.151, p = 0.042). We also observed that rs2071419 and rs3213434 significantly correlated with DEACMP-increased risk in the dominant, codominant, and overdominant genetic models. In addition, we speculated that the C allele of the rs2071419 polymorphism and the T allele of the rs3213434 polymorphism in NSE may increase the DEACMP risk (p = 0.011, p = 0.006).

Conclusions

The results show that rs2071419 and rs3213434 are susceptible sites of DEACMP. The NSE C allele of rs2071419 and T allele of rs3213434 and the haplotypes GGTTTC and CCTTTC may be risk factors for DEACMP.

Carbon monoxide intoxication in geriatric patients: How important are lactate values at admission?

PURPOSE

The aim of this study was to investigate the demographic and clinical characteristics and treatment modalities of elderly patients with carbon monoxide (CO) intoxication. The secondary aim was to evaluate the importance of plasma lactate values in the diagnosis of acute CO intoxication in geriatric patients.

METHODS

Data on geriatric patients who were admitted to the emergency department of Atatürk University Medical Faculty between January 2013 and April 2016 were analyzed retrospectively.

RESULTS

Of the 197 cases included in the study, 97 were in the intoxication group and 100 were in the control group; 82.5% of the intoxication cases had mild neurological symptoms and 17.5% had severe neurological symptoms. Carboxyhemoglobin levels were significantly higher in patients with severe neurological symptoms (p = 0.031). All patients with severe neurological symptoms received hyperbaric-oxygen therapy (p < 0.001). In the intoxication group, lactate levels were significantly higher than in the control group (p = 0.001). The specificity for lactate 4 mmol/L and above was found as 98.0% with a positive predictive value and negative predictive value of 84.5% and 53.3%, respectively.

CONCLUSION

High initial lactate levels may be a guide for cases with nonspecific symptoms in geriatric patients with suspected CO intoxication.

S-100β in predicting the need of hyperbaric oxygen in CO-induced delayed neurological sequels

BACKGROUND

Delayed neurological sequels (DNS) have been described after carbon monoxide (CO) poisoning. There is a need to find a new prognostic marker to guide the use of hyperbaric oxygen (HBO) therapy.

AIM

To evaluate serum S-100β level in patients presenting with acute CO poisoning as an indicator of poisoning severity and predictor of DNS occurrence and HBO need in those patients.

METHODS

This prospective cohort study included patients with acute CO poisoning. On admission, carboxyhemoglobin (COHb) and S-100β levels were measured. Patients were followed up for 6 months for signs of DNS.

RESULTS

Out of 50 patients, 6 only developed DNS. The mean of S-100β levels was significantly higher in patients with severe poisoning and those with DNS. Receiver operating characteristic curve analysis revealed that S-100β had an area under the curve 0. 871; at a cutoff value ≥ 0.67 µg/L, its sensitivity and specificity were 100% and 77.3%, respectively. The sensitivity of S-100β was significantly higher than that of COHb, while its specificity and overall accuracy were significantly higher than those of HBO criteria.

CONCLUSION

Serum S-100β level on admission could be a marker of poisoning severity and a predictor of CO-induced DNS development that guides the use of HBO therapy.

Serum neuron-specific enolase levels at presentation and long-term neurological sequelae after acute charcoal burning-induced carbon monoxide poisoning

OBJECTIVE

This study aimed to investigate whether clinical parameters and serum neuron-specific enolase (NSE) levels measured at emergency department (ED) presentation help stratify the risk of acute or delayed persistent severe neurological sequelae after acute carbon monoxide (CO) poisoning induced by charcoal burning.

METHODS

This retrospective study included 236 patients who suffered from CO poisoning. Demographic information, serum NSE levels measured in the ED, treatment, clinical course, and long-term neurological outcomes were recorded.

RESULTS

The median serum NSE level at presentation was 15.5 (10.9-22.7) ng/mL. No differences were observed in the duration of CO exposure; the initial Glasgow Coma Scale (GCS) score; the levels of arterial HCO₃^-, white blood cells (WBCs), C-reactive protein (CRP) or troponin I; or the frequency of abnormal diffusion-weighted imaging finding at presentation among the groups with different serum NSE levels at presentation. The incidences of acute and delayed persistent neurologic sequelae assessed at 22.3 months after acute charcoal CO poisoning were 5.1% and 8.5%, respectively. No difference in the NSE level was observed between patients stratified according to long-term neurological status. According to the multinomial logistic regression analysis, age, serum CRP levels and the initial GCS score were risk factors for the two types of persistent severe neurological sequelae, whereas troponin I levels were associated only with the acute persistent severe neurological sequelae. However, the adjusted NSE level was not a risk factor for any persistent neurological sequelae.

CONCLUSIONS

Serum NSE levels at presentation were not correlated with the risk of acute or delayed persistent neurological sequelae. Further studies with blood sampling at optimal time points and serial measurements should be conducted. Age, initial GCS score, and CRP levels may be risk factors for persistent severe neurological sequelae.

Serum neuron-specific enolase as an early predictor of delayed neuropsychiatric sequelae in patients with acute carbon monoxide poisoning

Delayed onset of neuropsychiatric symptoms after apparent recovery from acute carbon monoxide (CO) poisoning has been described as delayed neuropsychiatric sequelae (DNS). To date, there have been no studies on the utility of serum neuron-specific enolase (NSE), a marker of neuronal cell damage, as a predictive marker of DNS in acute CO poisoning. This retrospective observational study was performed on adult patients with acute CO poisoning consecutively treated over a 9-month period. Serum NSE was measured after emergency department arrival, and patients were divided into two groups. The DNS group comprised patients with delayed sequelae, while the non-DNS group included patients with none of these sequelae. A total of 98 patients with acute CO poisoning were enrolled in this study. DNS developed in eight patients. The median NSE value was significantly higher in the DNS group than in the non-DNS group. There was a statistical difference between the non-DNS group and the DNS group in terms of CO exposure time, Glasgow Coma Scale (GCS), loss of consciousness, creatinine kinase, and troponin I. GCS and NSE were the early predictors of development of DNS. The area under the curve according to the receiver operating characteristic curves of GCS, serum NSE, and GCS combined with serum NSE were 0.922, 0.836, and 0.969, respectively. In conclusion, initial GCS and NSE served as early predictors of development of DNS. Also, NSE might be a useful additional parameter that could improve the prediction accuracy of initial GCS.

Utility of serum concentration of protein S100 at admission to the medical intensive care unit in prediction of permanent neurological injury

Introduction

Admission to the intensive care unit (ICU) may be preceded by dramatic events leading to permanent neurological injury. Plasma S100 protein levels are proved to be clinically useful in predicting neurological outcome following cardiac arrest. It is unclear, however, whether this may be extrapolated to a broader population of ICU patients.

Aim

To assess the utility of plasma S100 protein in predicting death, permanent neurological damage, or unfavourable outcome at admission to the intensive care unit.

Material and methods

The concentration of plasma S100 protein was established in 102 patients on admission to the ICU, regardless of their neurological status and the reason for admission. The majority of patients were admitted with various cardiac diseases, excluding trauma patients. The patients were classified into three groups with the following binary outcomes: permanent neurological deficit or restoration of consciousness; unfavourable outcome (death or survival with permanent neurological deficit) or favourable outcome; and death or survival.

Results

Plasma S100 protein levels at admission facilitated the identification of patients who later developed a permanent neurological deficit or regained consciousness (p < 0.0001). All patients with plasma S100 protein over 0.532 μg/l at ICU admission either developed a permanent neurological deficit or had an unfavourable outcome (death or survival with permanent neurological deficit). However, sensitivity for this cut-off value was only 48% and 40%, respectively.

Conclusions

Plasma S100 protein levels over 0.532 μg/l are specific but not sensitive for both permanent neurological deficit and unfavourable outcome when assessed in a heterogeneous population at admission to the ICU.

Neuropsychological Evaluation of Children and Adolescents With Acute Carbon Monoxide Poisoning

OBJECTIVES

Carbon monoxide (CO) poisoning is a worldwide health problem. We have limited information regarding psychological adversities of CO poisoning in children and adolescents. The aim of this study was (1) to investigate the effects of severe CO poisoning on cognitive functions, mood, and behaviors in children and adolescents and (2) to identify factors related to occurrence of neuropsychological symptoms.

METHODS

This study included pediatric patients, who were evaluated after CO poisoning at the Department of Child and Adolescent Psychiatry between January 2012 and April 2013. The patients were evaluated at 2 time points. The first evaluation was done when they were discharged from emergency department, and the second evaluation was done 1 month after CO poisoning. Turkish versions of internationally recognized tests were used to evaluate anxiety, depressive symptoms, attention, visual-spatial skills, memory, and behaviors of patients.

RESULTS

Twenty-seven patients were analyzed. The mean age of the patients was 11.8 ± 2.7 years (range, 6-18 years). The mean carboxyhemoglobin level was 31.5% ± 7.8% (range, 19%-51%) dir. Delayed neurological sequel was observed in only 1 patient, who had headache and tinnitus. We found that carboxyhemoglobin level was not correlated with later neuropsychiatric test scores. However, we found a correlation between history of loss of consciousness and anxiety symptom level, hyperbaric oxygen (HBO) therapy session and behavioral problems, and time to HBO therapy and attention problems.

CONCLUSIONS

We suggest that CO exposure duration, history of loss of consciousness, time to HBO therapy, and the number of HBO therapy session affect neuropsychological symptom levels and occurrence of attention and behavioral problems.

Serum bilirubin value predicts hospital admission in carbon monoxide-poisoned patients. Active player or simple bystander?

OBJECTIVES

Although carbon monoxide poisoning is a major medical emergency, the armamentarium of recognized prognostic biomarkers displays unsatisfactory diagnostic performance for predicting cumulative endpoints.

METHODS

We performed a retrospective and observational study to identify all patients admitted for carbon monoxide poisoning during a 2-year period. Complete demographical and clinical information, along with the laboratory data regarding arterial carboxyhemoglobin, hemoglobin, blood lactate and total serum bilirubin, was retrieved.

RESULTS

The study population consisted of 38 poisoned patients (23 females and 15 males; mean age 39 ± 21 years). Compared with discharged subjects, hospitalized patients displayed significantly higher values for blood lactate and total serum bilirubin, whereas arterial carboxyhemoglobin and hemoglobin did not differ. In a univariate analysis, hospitalization was significantly associated with blood lactate and total serum bilirubin, but not with age, sex, hemoglobin or carboxyhemoglobin. The diagnostic performance obtained after combining the blood lactate and total serum bilirubin results (area under the curve, 0.90; 95% CI, 0.81-0.99; p<0.001) was better than that obtained for either parameter alone.

CONCLUSION

Although it remains unclear whether total serum bilirubin acts as an active player or a bystander, we conclude that the systematic assessment of bilirubin may, alongside lactate levels, provide useful information for clinical decision making regarding carbon monoxide poisoning.

Serum S100B level may be correlated with carbon monoxide poisoning

OBJECTIVE

To investigate the correlation between serum S100B level and carbon monoxide (CO) poisoning by meta-analysis.

METHODS

By searching both English and Chinese language-based electronic databases (PubMed, EBSCO, Ovid, Springerlink, Wiley, Web of Science, Wanfang databases, China national knowledge infrastructure (CNKI), VIP database, etc.) thoroughly, we tabulated and analyzed the collected data with the use of Comprehensive Meta-analysis 2.0 (CMA 2.0).

RESULTS

Totally 108 studies have been searched initially (92 studies in Chinese, 16 studies in English). Nine case-control studies (4 studies in English, 5 in Chinese) were chosen for an updated meta-analysis including 542 patients with CO poising and 236 healthy controls. Results identified that the serum S100B level were obviously higher than that in healthy controls (SMD=1.600, 95% CI=1.055-2.145, P<0.001). A subgroup based on the ethnicities revealed that the serum S100B level in Caucasian and Asian subgroups was clearly higher than serum S100B level in healthy controls (Asians: SMD=2.0624, 95% CI=1.736-3.511, P<0.001; Caucasians: SMD=0.447, 95% CI=0.197-0.697, P<0.001).

CONCLUSION

Serum S100B level may be correlated with the CO poisoning and could be effective biomarker for early diagnosis and treatment monitoring in CO poisoning.

The role of S100B protein, neuron-specific enolase, and glial fibrillary acidic protein in the evaluation of hypoxic brain injury in acute carbon monoxide poisoning

The main purpose of this study was to assess the role of S100B protein, neuron-specific enolase (NSE), and glial fibrillary acidic protein (GFAP) in the evaluation of hypoxic brain injury in acute carbon monoxide (CO)-poisoned patients. This cross-sectional study was conducted among the patients with acute CO poisoning who referred to the emergency department in a 1-year period. Serum levels of S100B protein, NSE, and GFAP were determined on admission. A total of 55 CO-poisoned patients (mean age ± standard deviation, 45 ± 20.3 years; 60% women) were included in the study. The control group consisted of 25 healthy adults. The patients were divided into two groups according to whether they were conscious or unconscious. The serum levels of S100B, NSE, and GFAP were higher in patients than that in the control group. There was no significant difference between unconscious and conscious patients with respect to these markers. There was a statistically significant difference between the conscious and unconscious patients and the control group in terms of S100B and NSE levels. There was also a statistically significant difference between the unconscious patients and the control group in terms of GFAP levels. Increased serum S100B, NSE, and GFAP levels are associated with acute CO poisoning. These biomarkers can be useful in assessing the clinical status of patients with CO poisoning.

Carbon monoxide poisoning in the 21st century

The world has experienced some very large shifts in the epidemiology of carbon monoxide poisoning, but it remains one of the most important toxicological global causes of morbidity and mortality. The diagnosis can be quickly confirmed with blood gases (pulse oximeters lack both sensitivity and specificity). Several strong predictors for serious neurological sequelae (prolonged loss of consciousness and elevated S100B) and reduced life expectancy (elevated troponin) are now reasonably well established. Despite this clearly defined high-risk group and extensive research into the pathophysiology, there has been little translation into better treatment. Much of the pathophysiological research has focused on hyperbaric oxygen. Yet it is apparent that clinical trials show little evidence for benefit from hyperbaric oxygen, and the most recent even raises the possibility of harm for repeated courses. More logical and promising potential antidotes have been under-researched, although recently both animal and small human studies suggest that erythropoietin may reduce S100B and prevent neurological sequelae. Major breakthroughs are likely to require further research on this and other treatments that may inhibit post-hypoxic inflammatory responses and apoptosis.

Potential use of hyperoxygenated solution as a treatment strategy for carbon monoxide poisoning

Aim

Carbon monoxide (CO) poisoning can cause permanent damage in tissues that are sensitive to hypoxia. We explored the feasibility and efficacy of using a hyperoxygenated solution (HOS) to treat severe acute CO poisoning in an animal model.

Methods

Male Sprague-Dawley rats were subjected to CO poisoning. The HOS was administered into the femoral vein of these rats through a catheter (10 ml/kg). Carboxyhemoglobin (COHb) and blood gases were used to assess the early damage caused by CO poisoning. S100β was measured to predict the development of late cognitive sequelae of CO. The Morris water maze test was performed to assess cognitive function, and Nissl staining was performed to observe histologic change.

Results

The COHb concentrations rapidly decreased at 5 min after the HOS administration; however, the PaO₂ and SaO₂ in rats treated with HOS increased significantly 5 min after the HOS administration. The S100β concentrations, which increased significantly after CO poisoning, increased at a much slower rate in the rats treated with HOS (HOS group) compared with the rats treated with O₂ inhalation (O₂ group). The escape latency in the place navigation test was shortened after CO poisoning on days 11-15 and days 26-30, and the swimming time in quadrant 4 in the spatial probe test on days 15 and 30 after CO poisoning was prolonged in the rats treated with HOS injection compared with the rats treated with oxygen inhalation or normal saline injection. The neuronal degeneration in the HOS group was alleviated than that in the CO or O₂ group.

Conclusion

HOS efficiently alleviates the brain damage in acute CO-poisoned rats and thus may serve as a new way to treat human patients with CO poisoning in clinical practice.

The role of serum cholinesterase activity and S100B protein in the evaluation of organophosphate poisoning

The aim of this study was to investigate the role of serum cholinesterase (SChE) activity and S100B protein in the evaluation of patients with acute organophosphate (OP) poisoning. Patients with acute OP poisoning admitted to the emergency department were included in this cross-sectional study. Twenty healthy volunteers served as controls. The SChE activity and serum S100B were determined on admission. Patients were divided into two groups (low severity and high severity). Thirty-six patients diagnosed with acute OP poisoning were enrolled. Serum S100B concentrations were higher in patients than in the control group ( p < 0.05). In the high-severity group, the SChE levels were lower and the S100Bs levels were higher than in the low-severity group. The SChE level was not different between survivors and nonsurvivors. S100B levels were higher in nonsurvivors than in survivors. According to receiver–operating characteristic curve analysis, the optimal cutoff value of serum S100B level to predict mortality was 236.5 pg/mL, with 71.4% sensitivity and 89.7% specificity. Our data suggest that initial SChE level is related to the clinical severity but not with mortality. S100B may be a useful marker in the assessment of clinical severity and prediction of mortality in acute OP poisoning.

The usefulness of the serum s100b protein for predicting delayed neurological sequelae in acute carbon monoxide poisoning

CONTEXT

Some patients with acute carbon monoxide poisoning will experience delayed neurological sequelae. Several factors associated with delayed neurological sequelae have been reported, but these factors are unsatisfactory for the assessment of unconscious patients.

OBJECTIVE

The aim of this study was to assess the usefulness of the serum S100B protein as a biochemical marker for predicting delayed neurological sequelae.

MATERIALS AND METHODS

In this retrospective study, we evaluated the data for patients who visited an emergency medical center once during a period of 7 months. The enrollment criteria were the diagnosis of acute carbon monoxide poisoning and the measurement of the serum S100B level. A standardized extraction using medical records was performed.

RESULT

A total of 71 patients were enrolled, and 10 patients (14.1%) presented delayed neurological sequelae. The delayed neurological sequelae group had a longer duration of carbon monoxide exposure, a longer duration of loss of consciousness, and a worse mental status (p-value < 0.001). In addition, the S100B protein levels were higher in the delayed neurological sequelae group (0.891 vs. 0.063, p-value < 0.001). Multiple logistic regression analysis showed that only the serum S100B protein level was independently associated with the development of delayed neurological sequelae (OR, 120.594; 95% CI, 4.194-3467.220), and a serum S100B protein level of more than 0.165 μg/L predicted the development of delayed neurological sequelae (sensitivity 90%, specificity 87%).

DISCUSSION AND CONCLUSION

In the present study, the level of serum S100B protein was found to be useful for evaluating acute CO poisoning patients and was found to be an independent predictor of the development of DNS after acute CO poisoning.

Neurological biomarkers in the perioperative period

The rapid detection and evaluation of patients presenting with perioperative neurological dysfunction is of great clinical relevance. Biomarkers have been defined as biological molecules that can be used as an indicator of new onset or progression of a biological process or effect of treatment. Biomarkers have become increasingly important in this setting to supplement other modalities of diagnosis such as EEG, sensory- or motor-evoked potential, transcranial Doppler, near-infrared spectroscopy, or imaging methods. A number of neuro-proteins have been identified and are currently under investigation for potential to provide insights into injury severity, outcome, and the ability to monitor cellular damage and molecular events that occur during neurological injury. S100B is a protein released by glial cells and is considered a marker of blood-brain barrier dysfunction. Clinical studies in patients undergoing cardiac and non-cardiac surgery indicate that serum levels of S100B are increased intraoperatively and after operation. The neurone-specific enolase has also been extensively investigated as a potential marker of neuronal injury in the context of cardiac and non-cardiac surgery. A third biomarker of interest is the Tau protein, which has been linked to neurodegenerative disorders. Tau appears to be more specific than the previous two biomarkers since it is only found in the central nervous system. The metalloproteinase and ubiquitin C terminal hydroxylase-L1 (UCH-L1) are the most recently researched markers; however, their usefulness is still unclear. This review presents a comprehensive overview of S100B, neuronal-specific enolase, metalloproteinases, and UCH-L1 in the perioperative period.

Neuropsychiatric disorders and risk factors in carbon monoxide intoxication

Neuropsychiatric sequelae may be observed in the late phases of carbon monoxide (CO) intoxication. Establishing a link between CO-related neuropsychiatric disorders and associated risk factors may decrease morbidity and mortality by means of appropriate treatment and counseling. The aim of the present study was to determine the relationship between neuropsychiatric outcomes of CO intoxication and demographic and clinical variables. Thirty patients who presented with CO intoxication and had no known neuropsychiatric disease, and 30 healthy controls were included. Physical examinations and laboratory tests were performed. Following the 1st therapy, they underwent mental and psychiatric tests 5 times (the time of discharge, during the 1st week, and during the 1st, 3rd, and 6th months). They underwent cerebral magnetic resonance imaging (MRI) at the end of the 1st month. They were evaluated by cognitive function tests at the 6th month. Lesions relevant to CO intoxication were detected in 46.7% of the patients via cranial computed tomography and in 13.3% via MRI. Evaluation of psychiatric tests revealed a clear decrease in cognitive functions, such as immediate memory, learning, reaching the criterion, spontaneous recall, attention, visual memory, and logical memory. It was found that the patients had anxiety within the 1st month, and the frequency of anxiety reached to the value of the control group by the end of the 6th month. In conclusion, we suggested that CO intoxication might lead to neuropsychiatric disorders. Our results emphasized that in addition to standard treatment, neuropsychiatric evaluation should also be performed in patients with CO intoxication.