Introduction: Various methods and devices have been described for cooling after cardiac arrest, but the ideal cooling method remains unclear. The aim of this study was to compare the neurological outcomes, efficacies and adverse events of surface and endovascular cooling techniques in cardiac arrest patients. Methods: We performed a multicenter, retrospective, registry-based study of adult cardiac arrest patients treated with therapeutic hypothermia presenting to 24 hospitals across South Korea from 2007 to 2012. We included patients who received therapeutic hypothermia using overall surface or endovascular cooling devices and compared the neurological outcomes, efficacies and adverse events of both cooling techniques. To adjust for differences in the baseline characteristics of each cooling method, we performed one-to-one matching by the propensity score. Results: In total, 803 patients were included in the analysis. Of these patients, 559 underwent surface cooling, and the remaining 244 patients underwent endovascular cooling. In the unmatched cohort, a greater number of adverse events occurred in the surface cooling group. Surface cooling was significantly associated with a poor neurological outcome (cerebral performance category 3–5) at hospital discharge (p = 0.01). After propensity score matching, surface cooling was not associated with poor neurological outcome and hospital mortality [odds ratio (OR): 1.26, 95% confidence interval (CI): 0.81-1.96, p = 0.31 and OR: 0.85, 95% CI: 0.55-1.30, p = 0.44, respectively]. Although surface cooling was associated with an increased incidence of adverse events (such as overcooling, rebound hyperthermia, rewarming related hypoglycemia and hypotension) compared with endovascular cooling, these complications were not associated with surface cooling using hydrogel pads. Conclusions: In the overall matched cohort, no significant difference in neurological outcomes and hospital morality was observed between the surface and endovascular cooling methods.

Therapeutic hypothermia (TH) has become the standard strategy for reducing brain damage in the postresuscitation period. The aim of this study was to investigate current TH performance and outcomes in out-of-hospital cardiac arrest (OHCA) survivors using data from the Korean Hypothermia Network (KORHN) registry. We used the KORHN registry, a web-based multicenter registry that includes 24 participating hospitals throughout the Republic of Korea. Adult comatose OHCA survivors treated with TH between 2007 and 2012 were included. The primary outcomes were neurological outcome at hospital discharge and in-hospital mortality. The secondary outcomes were TH performance and adverse events during TH. A total of 930 patients were included, of whom 556 (59.8%) survived to discharge and 249 (26.8%) were discharged with good neurologic outcomes. The median time from return of spontaneous circulation (ROSC) to the start of TH was 101 minutes (interquartile range [IQR], 46 to 200 minutes). The induction, maintenance, and rewarming durations were 150 minutes (IQR, 80 to 267 minutes), 1,440 minutes (IQR, 1,290 to 1,440 minutes), and 708 minutes (IQR, 420 to 900 minutes), respectively. The time from the ROSC to coronary angiography was 1,045 hours (IQR, 121 to 12,051 hours). Hyperglycemia (46.3%) was the most frequent adverse event. More than one-quarter of the OHCA survivors (26.8%) were discharged with good neurologic outcomes. TH performance was appropriately managed in terms of the factors related to its timing, including cooling start time and rewarming duration.

Carbon monoxide (CO) is well-known as toxic gas and intrinsic signaling molecule such as neurotransmitter and blood vessel relaxant. Recently, it has been reported that low concentration of CO exerts therapeutic actions under various pathological conditions including liver failure, heart failure, gastric cancer, and cardiac arrest. However, little has been known about the effect of CO in neurodegenerative diseases like Parkinson's disease (PD). To test whether CO could exert a beneficial action during oxidative cell death in PD, we examined the effects of CO on 6-hydroxydopamine (6-OHDA)-induced cell death in C6 glioma cells. Treatment of CO-releasing molecule-2 (CORM-2) significantly attenuated 6-OHDA-induced apoptotic cell death in a dose-dependent manner. CORM-2 treatment decreased Bax/Bcl2 ratio and caspase-3 activity, which had been increased by 6-OHDA. CORM-2 increased phosphorylation of NF-E2-related factor 2 (Nrf2) which is a transcription factor regulating antioxidant proteins. Subsequently, CORM-2 also increased the expression of heme oxygenase-1 and superoxide dismutases (CuZnSOD and MnSOD), which were antioxidant enzymes regulated by Nrf2. These results suggest that CO released by CORM-2 treatment may have protective effects against oxidative cell death in PD through the potentiation of cellular adaptive survival responses via activation of Nrf2 and upregulation of heme oxygenase-1, leading to increasing antioxidant defense capacity.

Background: To prepare for future work stoppages in the medical industry, this study aimed to identify the effects of healthcare worker strikes on the mortality rate of patients visiting the emergency department (ED) at six training hospitals in Daegu, Korea. Methods: We used a retrospective, cross-sectional, multicenter design to analyze the medical records of patients who visited six training hospitals in Daegu (August 21–September 8, 2020). For comparison, control period 1 was set as the same period in the previous year (August 21–September 8, 2019) and control period 2 was set as July 1–19, 2020. Patient characteristics including age, sex, and time of ED visit were investigated along with mode of arrival, length of ED stay, and in-hospital mortality. The experimental and control groups were compared using t-tests, and Mann-Whitney U-test, chi-square test, and Fisher exact tests, as appropriate. Univariate logistic regression was performed to identify significant factors, followed by multivariate logistic regression analysis. Results: During the study period, 31,357 patients visited the ED, of which 7,749 belonged to the experimental group. Control periods 1 and 2 included 13,100 and 10,243 patients, respectively. No significant in-hospital mortality differences were found between study periods; however, the results showed statistically significant differences in the length of ED stay. Conclusion: The ED resident strike did not influence the mortality rate of patients who visited the EDs of six training hospitals in Daegu. Furthermore, the number of patients admitted and the length of ED stay decreased during the strike period.

The purpose of this study was to investigate the molecular mechanism underlying oxidative and inflammatory neuronal cell death induced by endosulfan, a pesticide belonging to the chemical family of organochlorines. The cortical and hippocampal tissues derived from Sprague-Dawley (SD) rats treated with endosulfan exhibited increased intracellular accumulation of reactive oxygen species and oxidative damages to cellular macromolecules such as depletion of glutathione, lipid peroxidation, and protein carbonylation. Conversely, the expression of antioxidant enzymes including γ-glutamylcysteine ligase (GCL), superoxide dismutase (SOD), and heme oxygenase-1 (HO-1) was markedly reduced in the brain tissues exposed to endosulfan. Moreover, during endosulfan-induced neuronal cell death, mRNA expression of pro-inflammatory cytokines such as tumour necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) was elevated, which seemed to be mediated by the activation of nuclear factor-kappa B (NF-κB) by phosphorylation of p65 subunit. These results suggest a new molecular mechanism underlying the endosulfan-induced acute neurotoxicity via induction of oxidative stress and pro-inflammatory responses.

Background: Fatigue and rotation time are key factors affecting the quality of cardiopulmonary resuscitation (CPR). This study aimed to investigate the effects of rotation time on CPR duration, and sex on chest compression quality. Methods: In this randomized crossover simulation study, we enrolled 100 paramedic students stratified by sex and randomly grouped into 28 male and 22 female pairs. In the 2- and 1-minute scenarios, 2 participants performed CPR for 20 minutes with a rotation cycle of 2 minutes and 1 minute, respectively. After taking a break, they changed over and performed CPR again for 20 minutes. The switching of roles was performed with the students positioned on opposite sides of the mannequin. For chest compression quality, a set was defined as CPR performed by 1 pair in a 2-minute scenario for 4 minutes. The quality of CPR in each set was compared between the 2 groups. Results: The 1-minute group showed significantly higher chest compression depth than the 2-minute group (54.0 [51.5–57.0] vs 52.5 [48.5–56.5] mm, P = .001, respectively). The female 2-minute group showed decreased chest compression depth over time, and the 1-minute group showed significantly increased chest compression depth during all sets except the 2nd set (54.0 [51.9–55.1] vs 50.5 [48.5–53.8] mm [P = .030], 52.3 [49.4–54.5] vs 50.8 [47.0–53.1] mm [P = .080], 52.8 [49.8–54.5] vs 48.8 [45.4–51.6] mm [P = .002], 51.5 [48.5–53.3] vs 48.3 [44.5–50.6] mm [P = .004], and 50.8 [48.9–54.1] vs 47.5 [44.6–50.1] mm [P = .001], respectively). The fatigue scores in the 2-minute group were significantly higher during sets 4 and 5 than those in the 1-minute group. Conclusion: When rescuer fatigue increases during prolonged CPR owing to their physical strength and skill levels, the rotation of rescuers every minute would be helpful in maintaining high-quality CPR.