Cerebral ischemia is caused by perturbations in blood flow to the brain that trigger sequential and complex metabolic and cellular pathologies. This leads to brain tissue damage, including neuronal cell death and cerebral infarction, manifesting clinically as ischemic stroke, which is the cause of considerable morbidity and mortality worldwide. To analyze the underlying biological mechanisms and identify potential biomarkers of ischemic stroke, various in vitro and in vivo experimental models have been established investigating different molecular aspects, such as genes, microRNAs, and proteins. Yet, the metabolic and cellular pathologies of ischemic brain injury remain not fully elucidated, and the relationships among various pathological mechanisms are difficult to establish due to the heterogeneity and complexity of the disease. Metabolome-based techniques can provide clues about the cellular pathologic status of a condition as metabolic disturbances can represent an endpoint in biological phenomena. A number of investigations have analyzed metabolic changes in samples from cerebral ischemia patients and from various in vivo and in vitro models. We previously analyzed levels of amino acids and organic acids, as well as polyamine distribution in an in vivo rat model, and identified relationships between metabolic changes and cellular functions through bioinformatics tools. This review focuses on the metabolic and cellular changes in cerebral ischemia that offer a deeper understanding of the pathology underlying ischemic strokes and contribute to the development of new diagnostic and therapeutic approaches.

Objective. The aim of this study was to validate and compare the performance of serum paraquat level, severity index of paraquat poisoning (SIPP), Acute Physiology And Chronic Health Evaluation II (APACHE II), modified Simplified Acute Physiology Score II (MSAPS II), and modified Expanded Simplified Acute Physiology Score II (MSAPS IIe) calculated immediately after arrival on emergency department (ED) for assessing the mortality of acute paraquat poisoning. Methods. A retrospective study design was employed with the main outcome measure being mortality from year 2001 to 2010. MSAPS II and MSAPS IIe were employed in that assessment of the 24-hour urine output were not included. The performance of APACHE II, MSAPS II, MSAPS IIe, serum paraquat level and SIPP for prediction of mortality in acute paraquat poisoning were compared. Results. A total of 102 patients were enrolled in the study. The area under the ROC curve for APACHE II (0.800) was statistically lower than those for MSAPS II, MSAPS IIe, SIPP and serum paraquat (0.879, 0.893, 0.924,and 0.951, respectively). The Hosmer-Lemeshow goodness-of-fit test C statistic revealed that APACHE II, MSAPS II, MSAPS IIe and serum paraquat level showed good calibrations (chi-square 8.477 and p = 0.388, chi-square 4.614 and p = 0.798, chi-squared 5.301 and p = 0.725, chi-squared 1.009 and p = 0.985 respectively), but poor calibration for SIPP (chi-square 21.293 and p = 0.006). Conclusion. Serum paraquat level is still the most reliable prognosis factor in acute paraquat poisoning. But MSAPS II or MSAPS IIe calculated immediately after arrival on ED may be helpful to predict mortality in acute paraquat poisoning especially when hospital has no facility to measure serum paraquat level.

This study was conducted to evaluate a problem-oriented focused torso bedside ultrasound protocol termed “Sonographic Evaluation of Aetiology for Respiratory difficulty, Chest pain, and/or Hypotension” (SEARCH 8Es) for its ability to narrow differential diagnoses and increase physicians’ diagnostic confidence, and its diagnostic accuracy, for patients presenting with dyspnea, chest pain, or symptomatic hypotension. This single-center prospective observational study was conducted over 12 months in an emergency department and included 308 patients (184 men and 124 women; mean age, 67.7 ± 19.1 years) with emergent cardiopulmonary symptoms. The paired t-test was used to compare the number of differential diagnoses and physician’s level of confidence before and after SEARCH 8Es. The overall accuracy of the SEARCH 8Es protocol in differentiating 13 diagnostic entities was evaluated based on concordance (kappa coefficient) with the diagnosis made by the inpatient specialists. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated. SEARCH 8Es narrows the number of differential diagnoses (2.5 ± 1.5 vs. 1.4 ± 0.7; p < 0.001) and improves physicians’ diagnostic confidence (2.8 ± 0.8 vs. 4.3 ± 0.9; p < 0.001) significantly. The overall kappa coefficient value was 0.870 (p < 0.001), with the overall sensitivity, specificity, positive predictive value, and negative predictive value at 90.9%, 99.0%, 89.7%, and 99.0%, respectively. The SEARCH 8Es protocol helps emergency physicians to narrow the differential diagnoses, increase diagnostic confidence and provide accurate assessment of patients with dyspnea, chest pain, or symptomatic hypotension.

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.

Real-time ultrasound-guided infraclavicular proximal axillary venous catheterization is used in many clinical situations and provides the advantages of catheter stabilization, a reduced risk of catheter-related infection, and comfort for the patient without limitation of movement. However, unintended catheter tip dislocation and accidental arterial puncture occur occasionally. This study was designed to investigate the influence of arm position on catheter placement and complications. Patients were randomized to either the neutral group (n=240) or the abduction group (n=241). In the neutral group, patients were positioned with the head and shoulders placed in an anatomically neutral position and the arms kept by the side during catheterization. In the abduction group, the right upper arm was abducted at 90° from the trunk during catheterization. After real-time ultrasound-guided catheterization was carried out in the right infraclavicular proximal axillary vein, misplacement of the catheter and all complications were evaluated with ultrasound and chest radiography. The success rate of complete catheterization before evaluating the placement of the catheter was high in both groups (97.1 vs 98.8%, P=not significant). The incidence of accidental arterial puncture was not different (1.7 vs 0%, P=not significant). The incidence of misplacement of the catheter was higher in the neutral group than in the abduction group (3.9 vs 0.4%, P=0.01). There were no complications, such as haemothorax, pneumothorax, or injury to the brachial plexus and phrenic nerve, in either group. Upper arm abduction may minimize the risk of misplacement of the catheter during real-time ultrasound-guided infraclavicular proximal axillary venous catheterization. The trial was registered with the Clinical Trial Registry of Korea: https://cris.nih.go.kr/cris/index.jsp. Identifier: KCT0001417.