The agreement between jugular bulb and cerebrospinal fluid lactate levels in patients with out-of-hospital cardiac arrest.

We investigated the agreement between the jugular bulb (JB) and cerebrospinal fluid (CSF) lactate levels. The study was conducted from July 2021 to June 2023 as a prospective observational cohort study at a single center. The right jugular vein was accessed, and the placement of JB catheter tip was confirmed using lateral cervical spine X-ray. A lumbar catheter was inserted between the 3rd and 4th lumbar spine of the patient. Lactate levels were measured immediately, 24 h, 48 h, and 72 h after ROSC. In patients with a good neurological prognosis, kappa between JB and CSF lactate levels measured immediately, at 24 h, 48 h, and 72 h after ROSC were 0.08, 0.36, 0.14, - 0.05 (p = 0.65, 0.06, 0.48, and 0.75, respectively). However, in patients with a poor neurological prognosis, kappa between JB and CSF lactate levels measured immediately, at 24 h, 48 h, and 72 h after ROSC were 0.38, 0.21, 0.22, 0.12 (p = 0.001, 0.04, 0.04, and 0.27, respectively). This study demonstrated that JB lactate levels exhibited significant agreement with arterial lactate levels, compared to CSF lactate levels. Therefore, this should be considered when using JB lactate to monitor cerebral metabolism.

Cerebrospinal Fluid Dynamics and Partial Pressure of Carbon Dioxide as Prognostic Indicators in Hypoxic-Ischemic Brain Injury Following Cardiac Arrest.

Changes in cerebrospinal fluid (CSF) dynamics can have adverse effects on neuronal function. We hypothesized that patients with hypoxic-ischemic brain injury (HIBI) showing poor neurological outcomes after cardiac arrest (CA) would exhibit changes in CSF dynamics, leading to abnormalities in gas diffusion within the CSF. Therefore, we investigated the prognostic value of the CSF partial pressure of carbon dioxide (PcsfCO2) in CA survivors who underwent targeted temperature management (TTM). We retrospectively analyzed the 6-month neurological outcomes, CSF, and arterial blood gas parameters of 67 CA survivors. Patients were divided into good and poor neurological outcome groups, and the predictive value of PcsfCO2 for poor neurological outcomes was assessed using receiver operating characteristic curve analysis. Among all patients, 39 (58.2%) had poor neurological outcomes. Significant differences in PcsfCO2 levels between the groups were observed, with lower PcsfCO2 levels on Day 1 showing the highest predictive value at a cutoff of 30 mmHg (area under the curve, sensitivity, and specificity were 0.823, 77.8%, and 79.0%, respectively). These results suggest that PcsfCO2 might serve not only as a unique marker for the severity of hypoxic-ischemic brain injury (HIBI), independent of extracorporeal CO2 levels, but also as an objective indicator of changes in CSF dynamics. This study highlights the potential prognostic and diagnostic utility of PcsfCO2 during TTM in CA survivors, emphasizing its importance in evaluating CSF dynamics and neurological recovery post CA. However, larger multicenter studies are warranted to address potential limitations associated with sample size and outcome assessment methods.

Blood-brain barrier permeability for the first 24 hours in hypoxic-ischemic brain injury following cardiac arrest.

BACKGROUND: This study aimed to explore the changes in blood-brain barrier (BBB) permeability and intracranial pressure (ICP) for the first 24 h after the return of spontaneous circulation (ROSC) and their association with injury severity of cardiac arrest. METHODS: This prospective study analysed the BBB permeability assessed using the albumin quotient (Qa) and ICP every 2 h for the first 24 h after ROSC. The injury severity of cardiac arrest was assessed using Pittsburgh Cardiac Arrest Category (PCAC) scores. The primary outcome was the time course of changes in the BBB permeability and ICP for the first 24 h after ROSC and their association with injury severity (PCAC scores of 1-4). RESULTS: Qa and ICP were measured 274 and 197 times, respectively, in 32 enrolled patients. Overall, the BBB permeability increased progressively over time after ROSC, and then it increased significantly at 18 h after ROSC compared with the baseline. In contrast, the ICP revealed non-significant changes for the first 24 h after ROSC. The Qa in the PCAC 2 group was < 0.01, indicating normal or mild BBB disruption at all time points, whereas the PCAC 3 and 4 groups showed a significant increase in BBB permeability at 14 and 22 h, and 12 and 14 h after ROSC, respectively. CONCLUSION: BBB permeability increased progressively over time for the first 24 h after ROSC despite post-resuscitation care, whereas ICP did not change over time. BBB permeability has an individual pattern when stratified by injury severity.

Sex differences in in-hospital management in patients with sepsis and septic shock: a prospective multicenter observational study.

Sex differences in the in-hospital management of sepsis exist. Previous studies either included patients with sepsis that was defined using previous definitions of sepsis or evaluated the 3-h bundle therapy. Therefore, this study sought to assess sex differences in 1-h bundle therapy and in-hospital management among patients with sepsis and septic shock, defined according to the Sepsis-3 definitions. This observational study used data from Korean Shock Society (KoSS) registry, a prospective multicenter sepsis registry. Adult patients with sepsis between June 2018 and December 2021 were included in this study. The primary outcome was adherence to 1-h bundle therapy. Propensity score matching (PSM) and multivariable logistic regression analyses were performed. Among 3264 patients with sepsis, 3129 were analyzed. PSM yielded 2380 matched patients (1190 men and 1190 women). After PSM, 1-h bundle therapy was performed less frequently in women than in men (13.0% vs. 19.2%; p < 0.001). Among the bundle therapy components, broad-spectrum antibiotics were administered less frequently in women than in men (25.4% vs. 31.6%, p < 0.001), whereas adequate fluid resuscitation was performed more frequently in women than in men (96.8% vs. 95.0%, p = 0.029). In multivariable logistic regression analysis, 1-h bundle therapy was performed less frequently in women than in men [adjusted odds ratio (aOR) 1.559; 95% confidence interval (CI) 1.245-1.951; p < 0.001] after adjustment. Among the bundle therapy components, broad-spectrum antibiotics were administered less frequently to women than men (aOR 1.339, 95% CI 1.118-1.605; p = 0.002), whereas adequate fluid resuscitation was performed more frequently for women than for men (aOR 0.629, 95% CI 0.413-0.959; p = 0.031). Invasive arterial blood pressure monitoring was performed less frequently in women than in men. Resuscitation fluid, vasopressor, steroid, central-line insertion, ICU admission, length of stay in the emergency department, mechanical ventilator use, and renal replacement therapy use were comparable for both the sexes. Among patients with sepsis and septic shock, 1-h bundle therapy was performed less frequently in women than in men. Continuous efforts are required to increase adherence to the 1-h bundle therapy and to decrease sex differences in the in-hospital management of patients with sepsis and septic shock.

Distribution and elimination kinetics of midazolam and metabolites after post-resuscitation care: a prospective observational study.

Administration of sedatives for post-resuscitation care can complicate the determination of the optimal timing to avoid inappropriate, pessimistic prognostications. This prospective study aimed to investigate the distribution and elimination kinetics of midazolam (MDZ) and its metabolites, and their association with awakening time. The concentrations of MDZ and its seven metabolites were measured immediately and at 4, 8, 12, and 24 h after the discontinuation of MDZ infusion, using liquid chromatography-tandem mass spectrometry. The area under the time-plasma concentration curve from 0 to 24 h after MDZ discontinuation (AUClast) was calculated based on the trapezoidal rule. Of the 15 enrolled patients, seven awakened after the discontinuation of MDZ infusion. MDZ and three of its metabolites were major compounds and their elimination kinetics followed a first-order elimination profile. In the multivariable analysis, only MDZ was associated with awakening time (AUClast: R2 = 0.59, p = 0.03; AUCinf: R2 = 0.96, p < 0.001). Specifically, a 0.001% increase in MDZ AUC was associated with a 1% increase in awakening time. In the individual regression analysis between MDZ concentration and awakening time, the mean MDZ concentration at awakening time was 16.8 ng/mL. The AUC of MDZ is the only significant factor associated with the awakening time.

Comparison of modified quick sequential organ failure assessment models as triage tools for febrile patients.

Object: Effective triage of febrile patients in the emergency department is crucial during times of overcrowding to prioritize care and allocate resources, especially during pandemics. However, available triage tools often require laboratory data and lack accuracy. We aimed to develop a simple and accurate triage tool for febrile patients by modifying the qSOFA score. Methods: We retrospectively analyzed data from 7,303 febrile patients and created modified versions of qSOFA using factors identified through multivariable analysis. The performance of these modified qSOFAs in predicting in hospital mortality and intensive care unit (ICU) admission was compared using the area under the receiver operating characteristic curve (AUROC). Results: Through multivariable analysis, the identified factors were age (A), male sex (M), SpO2 (S), and lactate levels (L). The AUROCs of ASqSOFA (for in-hospital mortality: 0.812; 95% CI: 0.789-0.835, for ICU admission: 0.794; 95% CI: 0.771-0.817), which included age and SpO2 with qSOFA, were simple and not inferior to other more complex models (e.g., ASMqSOFA, ASLqSOFA, and ASMLqSOFA). ASqSOFA also displayed significantly higher AUROC than other triage scales, such as the modified early warning score and Korean triage and acuity scale. The optimal cut-off score of ASqSOFA for the outcome was 2 and the score for redistribution to a lower-level emergency department was 0. Conclusion: We demonstrated that ASqSOFA can be employed as a simple and efficient triage tool for emergency febrile patients to aid in resource distribution during overcrowding. It may also be applicable in pre-hospital settings for febrile patient triage.

Combination strategy for prognostication in patients undergoing post-resuscitation care after cardiac arrest.

This study investigated the prognostic performance of combination strategies using a multimodal approach in patients treated after cardiac arrest. Prospectively collected registry data were used for this retrospective analysis. Poor outcome was defined as a cerebral performance category of 3-5 at 6 months. Predictors of poor outcome were absence of ocular reflexes (PR/CR) without confounding factors, a highly malignant pattern on the most recent electroencephalography, defined as suppressed background with or without periodic discharges and burst-suppression, high neuron-specific enolase (NSE) after 48 h, and diffuse injury on imaging studies (computed tomography or diffusion-weighted imaging [DWI]) at 72-96 h. The prognostic performances for poor outcomes were analyzed for sensitivity and specificity. A total of 130 patients were included in the analysis. Of these, 68 (52.3%) patients had poor outcomes. The best prognostic performance was observed with the combination of absent PR/CR, high NSE, and diffuse injury on DWI [91.2%, 95% confidence interval (CI) 80.7-97.1], whereas the combination strategy of all available predictors did not improve prognostic performance (87.8%, 95% CI 73.8-95.9). Combining three of the predictors may improve prognostic performance and be more efficient than adding all tests indiscriminately, given limited medical resources.

Quantitative analysis of early apparent diffusion coefficient values from MRIs for predicting neurological prognosis in survivors of out-of-hospital cardiac arrest: an observational study.

BACKGROUND: This study aimed to quantitatively analyse ultra-early brain diffusion-weighted magnetic resonance imaging (DW-MRI) findings to determine the apparent diffusion coefficient (ADC) threshold associated with neurological outcomes in comatose survivors of out-of-hospital cardiac arrest (OHCA). METHODS: This retrospective study included adult survivors of comatose OHCA who underwent DW-MRI imaging scans using a 3-T MRI scanner within 6 h of the return of spontaneous circulation (ROSC). We investigated the association between neurological outcomes and ADC values obtained through voxel-based analysis on DW-MRI. Additionally, we constructed multivariable logistic regression models with pupillary light reflex (PLR), serum neuron-specific enolase (NSE), and ADC values as independent variables to predict poor neurological outcomes. The primary outcome was poor neurological outcome 6 months after ROSC, determined by the Cerebral Performance Category 3-5. RESULTS: Overall, 131 patients (26% female) were analysed, of whom 74 (57%) showed poor neurological outcomes. The group with a poor neurological outcome had lower mean whole brain ADC values (739.1 vs. 787.1 × 10-6 mm/s) and higher percentages of voxels with ADC below threshold in all ranges (250-1150) (all P < 0.001). The mean whole brain ADC values (area under the receiver operating characteristic curve [AUC] 0.83) and the percentage of voxels with ADC below 600 (AUC 0.81) had the highest sensitivity of 51% (95% confidence interval [CI] 39.4-63.1; cut-off value ≤ 739.2 × 10-6 mm2/s and > 17.2%, respectively) when the false positive rate (FPR) was 0%. In the multivariable model, which also included PLR, NSE, and mean whole brain ADC values, poor neurological outcome was predicted with the highest accuracy (AUC 0.91; 51% sensitivity). This model showed more accurate prediction and sensitivity at an FPR of 0% than did the combination of PLR and NSE (AUC 0.86; 30% sensitivity; P = 0.03). CONCLUSIONS: In this cohort study, early voxel-based quantitative ADC analysis after ROSC was associated with poor neurological outcomes 6 months after cardiac arrest. The mean whole brain ADC value demonstrated the highest sensitivity when the FPR was 0%, and including it in the multivariable model improved the prediction of poor neurological outcomes.

Differences in Cerebral Metabolism between Moderate- and High-Severity Groups of Patients with Out-of-Hospital Cardiac Arrest Undergoing Target Temperature Management.

The aim of this study was to investigate the differences in cerebral metabolism and the prognostic value of cerebrospinal fluid (CSF) lactate 24 h after the return of spontaneous circulation (ROSC) in patients with out-of-hospital cardiac arrest (OHCA). CSF lactate and pyruvate levels were measured immediately and every 2 h for 24 h after the ROSC. The distribution of cerebral mitochondrial dysfunction (MD) and cerebral ischemia was also evaluated. In the moderate-severity group, the absence of cerebral MD or ischemia was observed in six patients (40.0%) immediately after ROSC and in nine patients (60.0%) 24 h after the ROSC. In the high-severity group, the absence of cerebral MD or ischemia was observed in four patients (30.8%) immediately after ROSC and in three patients (23.1%) 24 h after the ROSC. The distribution of cerebral metabolism over time varied depending on the severity of the OHCA. The predictive value of CSF lactate levels for a poor neurological prognosis was better for patients in the moderate-severity group than for the overall patient cohort. Therefore, the severity in the patients with OHCA should be considered when studying cerebral metabolism or using CSF lactate as a prognostic tool.

Preliminary Prognostication for Good Neurological Outcomes in the Early Stage of Post-Cardiac Arrest Care.

We investigated prognostic strategies for predicting good outcomes in the early stage of post-cardiac-arrest care using multiple prognostic tests that are available until 24 h after the return of spontaneous circulation (ROSC). A retrospective analysis was conducted on 138 out-of-hospital cardiac-arrest patients who underwent prognostic tests, including the gray-white-matter ratio (GWR-BG), the Glasgow Coma Scale motor (GCS-M) score before sedative administration, and the neuron-specific enolase (NSE) level measured at 24 h after the ROSC. We investigated the prognostic performances of the tests as single predictors and in various combination strategies. Classification and regression-tree analysis were used to provide a reliable model for the risk stratification. Out of all the patients, 55 (44.0%) had good outcomes. The NSE level showed the highest prognostic performance as a single prognostic test and provided improved specificities (>70%) and sensitivities (>98%) when used in combination strategies. Low NSE levels (≤32.1 ng/mL) and high GCS-M (≥4) scores identified good outcomes without misclassification. The overall accuracy for good outcomes was 81.8%. In comatose patients with low NSE levels or high GCS-M scores, the premature withdrawal of life-sustaining therapy should be avoided, thereby complying with the formal prognostication-strategy algorithm after at least 72 h from the ROSC.

Time-course relationship between cerebrospinal fluid and serum concentrations of midazolam and albumin in patients with cardiac arrest undergoing targeted temperature management.

AIM: To understand the serum and cerebrospinal fluid (CSF) distribution of midazolam is important for proper timing of neurological prognostication of targeted temperature management(TTM) patients. Midazolam binds extensively to albumin in serum although non protein bound form exist in CSF. We investigated the time-course of CSF, serum concentrations of midazolam and albumin in patients with cardiac arrest who underwent TTM. METHODS: This prospective, single-center, observational study was conducted between May 2020 and April 2022. Midazolam and albumin concentrations in CSF and serum were quantified 0, 24, 48, and 72 h after the return of spontaneous circulation for comparison between the good (Cerebral Performance Category (CPC) 1 and 2) and poor (CPC 3, 4, and 5) neurologic outcome groups. The CSF/serum (C/S) ratios of midazolam and albumin concentrations were determined, along with their correlation coefficients. RESULTS: Of the 19 enrolled patients, 13 experienced poor outcomes. At 0 h, serum midazolam concentrations were the lowest, whereas serum albumin levels were the highest; in the CSF, the concentrations of both peaked at 24 h. There were no significant inter-group differences in midazolam concentrations in CSF or serum. The C/S ratios of midazolam and albumin significantly differed between the groups. Moderate to strong positive correlations were observed between the midazolam and albumin C/S ratios. CONCLUSION: In CSF, midazolam and albumin concentrations peaked 24 h post-cardiac arrest. Midazolam and albumin C/S ratios were significantly higher in the poor outcome group and positively correlated with each other, suggesting blood-brain barrier disruption 24 h post-cardiac arrest.

Tailored versus conventional surgical debridement in complex facial lacerations in emergency department: A retrospective study.

Surgical debridement is an essential step in treating complex facial lacerations (CFL). As the CFL severity increases, conventional surgical debridement (CSD) of wound edges becomes difficult and may be insufficient. Because the severity and shape of each CFL vary, it is necessary to tailor the customized pre-excisional design, that is, tailored surgical debridement (TSD), for each case before performing surgical debridement. The use of TSD can enable effective debridement of CFL with higher severity. This study aimed to compare the cosmetic outcomes and complication incidence of CSD versus TSD according to CFL severity. In this retrospective observational study, eligible patients with CFL who visited the emergency department between August 2020 and December 2021 were examined. CFL severity was graded as Grades I and II. The outcomes of CSD and TSD were compared using the scar cosmesis assessment and rating (SCAR) scale, wherein a good cosmetic outcome was defined as a SCAR score of ≤ 2. The percentage of good cosmetic outcomes between the 2 groups was compared. The SCAR score and percentage of good cosmetic outcomes between the 2 groups were compared overall and by severity. For analyzing complication incidence, asymmetry, infection, and dehiscence incidence were compared. In total, 252 patients were enrolled [121 (48.0%) CSD and 131 (52.0%) TSD]. The median SCAR scores were 3 (1-5) and 1 (0-2) in all enrolled patients (P < .001), 2 (0-4), and 1 (0-1) in Grade I patients (P < .01), and 5 (4-6) and 1 (1-2) in Grade II patients (P < .001) in the CSD and TSD groups, respectively. The percentage of good cosmetic outcomes was 46.3% and 84.0% overall (P < .001), 59.6% and 85.0% in Grade I patients (P < .01), and 9.4% and 83.5% in Grade II patients (P < .001) in the CSD and TSD groups, respectively. The incidence of complications was significantly higher in the CSD group than in the TSD group, but this was limited to asymmetry. No significant difference was noted in infection or dehiscence. Compared with CSD, TSD can lead to an objectively good cosmetic prognosis at higher CFL severity and can reduce facial asymmetry occurrence.

Association of ultra-early diffusion-weighted magnetic resonance imaging with neurological outcomes after out-of-hospital cardiac arrest.

BACKGROUND: This study aimed to investigate the association between ultra-early (within 6 h after return of spontaneous circulation [ROSC]) brain diffusion-weighted magnetic resonance imaging (DW-MRI) and neurological outcomes in comatose survivors after out-of-hospital cardiac arrest. METHODS: We conducted a registry-based observational study from May 2018 to February 2022 at a Chungnam national university hospital in Daejeon, Korea. Presence of high-signal intensity (HSI) (PHSI) was defined as a HSI on DW-MRI with corresponding hypoattenuation on the apparent diffusion coefficient map irrespective of volume after hypoxic ischemic brain injury; absence of HSI was defined as AHSI. The primary outcome was the dichotomized cerebral performance category (CPC) at 6 months, defined as good (CPC 1-2) or poor (CPC 3-5). RESULTS: Of the 110 patients (30 women [27.3%]; median (interquartile range [IQR]) age, 58 [38-69] years), 48 (43.6%) had a good neurological outcome, time from ROSC to MRI scan was 2.8 h (IQR 2.0-4.0 h), and the PHSI on DW-MRI was observed in 46 (41.8%) patients. No patients in the PHSI group had a good neurological outcome compared with 48 (75%) patients in the AHSI group. In the AHSI group, cerebrospinal fluid (CSF) neuron-specific enolase (NSE) levels were significantly lower in the group with good neurological outcome compared to the group with poor neurological outcome (20.1 [14.4-30.7] ng/mL vs. 84.3 [32.4-167.0] ng/mL, P < 0.001). The area under the curve for PHSI on DW-MRI was 0.87 (95% confidence interval [CI] 0.80-0.93), and the specificity and sensitivity for predicting a poor neurological outcome were 100% (95% CI 91.2%-100%) and 74.2% (95% CI 62.0-83.5%), respectively. A higher sensitivity was observed when CSF NSE levels were combined (88.7% [95% CI 77.1-95.1%]; 100% specificity). CONCLUSIONS: In this cohort study, PHSI findings on ultra-early DW-MRI were associated with poor neurological outcomes 6 months following the cardiac arrest. The combined CSF NSE levels showed higher sensitivity at 100% specificity than on DW-MRI alone. Prospective multicenter studies are required to confirm these results.

Acute contralateral reexpansion pulmonary edema within a few hours of pleural drainage.

We report a case of an 83-year-old male patient with massive tuberculous pleural effusion. Percutaneous drainage was performed following a diagnosis of tuberculous pleurisy. Fifteen minutes into the procedure, the patient's condition deteriorated suddenly, necessitating mechanical ventilatory support. A chest radiograph performed after intubation showed partial collapse of the affected lung with pneumothorax. Despite sufficient air drainage and lung expansion, the patient's oxygen demand remained high. A repeat chest radiograph performed 30 minutes after chest tube insertion revealed partial expansion of the affected lung and severe infiltrative patterns in the unaffected lung, suggesting contralateral reexpansion pulmonary edema.

Serum total cholesterol level as a potential predictive biomarker for neurological outcomes in cardiac arrest survivors who underwent target temperature management.

Cholesterol is an essential substance to maintain cell membranes. Low levels of total cholesterol (TC) are associated with poor prognosis in critically ill patients. Cardiac arrest-induced whole-body ischemia and reperfusion injury cause a sepsis-like syndrome. The Cholesterol level in post-cardiac arrest patients may indicate the degree of endotoxemia or inflammation caused by ischemic and reperfusion injury. We aimed to investigate the association of TC levels with neurologic outcome of out-of-hospital cardiac arrest (OHCA) survivors who underwent target temperature management (TTM). This was a retrospective single-center observational study from May 2018 to April 2021 on a cohort of 106 patients. TC levels were determined in samples obtained immediately and at 24, 48, and 72 hours after the return of spontaneous circulation (ROSC). The primary outcome was poor neurologic outcome at 3 months after ROSC. Poor neurologic outcome was defined by cerebral performance categories 3 to 5. Sixty patients had a poor neurologic outcome. TC levels were significantly lower in the poor neurologic outcome group at each time point. The TC levels for predicting poor neurologic outcome had a sensitivity of 80.8%, with 67.6% specificity at 48 hours (TC48) after ROSC. The areas under the curve value of TC48 was 0.771 (0.670-0.853), with a cutoff value of 114 mg/dL. TC level at 48 hours after ROSC was a helpful marker for the 3-month poor neurologic outcome. This might be an easily accessible predictive marker of neurologic outcome in OHCA survivors treated with TTM.

Development of a strategy for assessing blood-brain barrier disruption using serum S100 calcium-binding protein B and neuron-specific enolase in early stage of neuroemergencies: A preliminary study.

BACKGROUND: Rapid disease progression in neuroemergencies is associated with blood-brain barrier (BBB) disruption. We investigated a less invasive strategy for assessing BBB status by evaluating S100 calcium-binding protein B (S100B) and neuron-specific enolase (NSE) at early stages of the hypoxic-ischemic brain injury (HIBI) cascade. METHODS: This retrospective study used prospectively collected data from patients with out-of-hospital cardiac arrest (August 2019-July 2021). Albumin specimens obtained from serum and cerebrospinal fluid via arterial catheter and lumbar puncture were used to measure the albumin quotient (Qa), which is widely accepted as the gold standard method for detecting BBB disruption. Serum S100B and NSE levels were measured simultaneously following the return of spontaneous circulation. We conducted linear regression to evaluate the relationship between S100B and Qa and the predictive performance of S100B for abnormal Qa. The primary study outcome was abnormal Qa (>0.007). RESULTS: Forty-one patients were enrolled; 30 showed an abnormal Qa suggestive of BBB disruption. S100B levels were significantly higher than in those with a normal Qa (0.244 µg/L [interquartile range [IQR], 0.146-0.823 vs 0.754 µg/L [IQR, 0.317-2.228], P = .03). We report a positive correlation between serum S100B and Qa (R2 = 0.110; P = .04). The area under the receiver operating characteristics curve (AUROC) evaluating the predictive performance of S100B with respect to abnormal Qa was 0.718 (95% confidence interval, 0.556-0.847). The cutoff value for S100B (with respect to BBB disruption) in the total cohort was 0.283 µg/L (sensitivity, 80.0%; specificity, 72.7%). Subgroup analyses in patients with serum neuron-specific enolase (NSE) levels of <40.8 ng/mL (excluding those with established neuronal cell injury) showed an improved correlation coefficient (R2 = 0.382; P < .01) and predictive performance (AUROC, 0.836 [95% confidence interval, 0.629-0.954]) compared with the total cohort. CONCLUSIONS: Serum S100B obtained at an early stage of the HIBI cascade is associated with abnormal Qa, suggesting BBB disruption. The predictive performance of S100B and the correlation between serum S100B and Qa can be improved using a complementary strategy (i.e., evaluations of S100B and NSE levels) that combines considerations of cell damage in astrocytes and neurons.