Association between Conversion to Shockable Rhythms and Survival with Favorable Neurological Outcomes for Out-of-Hospital Cardiac Arrests.

BACKGROUND: The initial cardiac rhythm in out-of-hospital cardiac arrest (OHCA) portends different prognoses and affects treatment decisions. Initial shockable rhythms are associated with good survival and neurological outcomes but there is conflicting evidence for those who initially present with non-shockable rhythms. The aim of this study is to evaluate if OHCA with conversion from non-shockable (i.e., asystole and pulseless electrical activity) rhythms to shockable rhythms compared to OHCA remaining in non-shockable rhythms is associated with better survival and neurological outcomes. METHOD: OHCA cases from the Pan-Asian Resuscitation Outcomes Study registry in 13 countries between January 2009 and February 2018 were retrospectively analyzed. Cases with missing initial rhythms, age <18 years, presumed non-medical cause of arrest, and not conveyed by emergency medical services were excluded. Multivariable logistic regression analysis was performed to evaluate the relationship between initial and subsequent shockable rhythm, survival to discharge, and survival with favorable neurological outcomes (cerebral performance category 1 or 2). RESULTS: Of the 116,387 cases included. 11,153 (9.6%) had initial shockable rhythms and 9,765 (8.4%) subsequently converted to shockable rhythms. Japan had the lowest proportion of OHCA patients with initial shockable rhythms (7.3%). For OHCA with initial shockable rhythm, the adjusted odds ratios (aOR) for survival and good neurological outcomes were 8.11 (95% confidence interval [CI] 7.62-8.63) and 15.4 (95%CI 14.1-16.8) respectively. For OHCA that converted from initial non-shockable to shockable rhythms, the aORs for survival and good neurological outcomes were 1.23 (95%CI 1.10-1.37) and 1.61 (95%CI 1.35-1.91) respectively. The aORs for survival and good neurological outcomes were 1.48 (95%CI 1.22-1.79) and 1.92 (95%CI 1.3 - 2.84) respectively for initial asystole, while the aOR for survival in initial pulseless electrical activity patients was 0.83 (95%CI 0.71-0.98). Prehospital adrenaline administration had the highest aOR (2.05, 95%CI 1.93-2.18) for conversion to shockable rhythm. CONCLUSION: In this ambidirectional cohort study, conversion from non-shockable to shockable rhythm was associated with improved survival and neurologic outcomes compared to rhythms that continued to be non-shockable. Continued advanced resuscitation may be beneficial for OHCA with subsequent conversion to shockable rhythms.

Quality between mechanical compression on reducible stretcher versus manual compression on standard stretcher in small elevator.

OBJECTIVES: Manual cardiopulmonary resuscitation (CPR) during vertical transport in small elevators using standard stretcher for out-of-hospital cardiac arrest can raise concerns with diminishing quality. Mechanical CPR on a reducible stretcher (RS-CPR) that can be shortened in the length was tested to compare the CPR quality with manual CPR on a standard stretcher (SS-CPR). METHODS: A randomized crossover manikin simulation was designed. Three teams of emergency medical technicians were recruited to perform serial CPR simulations using two different protocols (RS-CPR and SS-CPR) according to a randomization; the first 6 minutes of manual CPR at the scene was identical for both scenarios and two different protocols during vertical transport in a small elevator followed on a basis of cross-over assignment. The LUCAS-2 Chest Compression System (Zolife AB, Lund, Sweden) was used for RS-CPR. CPR quality was measured using a resuscitation manikin (Resusci Anne QCPR, Laerdal Medical, Stavanger, Norway) in terms of no flow fraction, compression depth, and rate (median and IQR). RESULTS: A total of 42 simulations were analyzed. CPR quality did not differ significantly at the scene. No flow fraction (%) was significantly lower when the stretcher was moving in RS-CPR then SS-CPR (36.0 (33.8-38.7) vs 44.0 (36.8-54.4), P< .01). RS-CPR showed significantly better quality than SS-CPR; 93.2 (50.6-95.6) vs 14.8 (0-20.8) for adequate depth (P< 0.01), and 97.5 (96.6-98.2) vs 68.9(43.4-78.5) for adequate rate (P< .01). CONCLUSION: Mechanical CPR on a reducible stretcher during vertical transport showed significant improvement in CPR quality in terms of no-flow fraction, compression depth, and rate compared with manual CPR on a standard stretcher.

Pediatric Age-Adjusted Shock Index as a Predictor of Mortality by Sex Disparity in Pediatric Trauma: A Pan-Asian Trauma Outcome Study

Purpose@#There has been no report of sex-specific, pediatric age-adjusted shock index (PASI) for pediatric trauma patients in previous studies. We aimed to determine the association between the PASI and in-hospital mortality of pediatric trauma patients and whether this association differs depending on sex. @*Materials and Methods@#This is a prospective, multinational, and multicenter cohort study using the Pan-Asian Trauma Outcome Study (PATOS) registry in the Asia-Pacific region, conducted in pediatric patients who visited the participating hospitals. The main exposure of our study was abnormal (elevated) PASI measured in an emergency department. The main outcome was in-hospital mortality. We performed a multivariable logistic regression analysis to estimate the association between abnormal PASI and study outcomes after adjusting for potential confounders. An interaction analysis between PASI and sex was also conducted. @*Results@#Of 6280 pediatric trauma patients, 10.9% (686) of the patients had abnormal PASI. In multivariable logistic regression analysis, abnormal PASI was significantly associated with increased in-hospital mortality [adjusted odds ratios (aOR), 1.74; 95% confidence interval (CI), 1.13–2.47]. Abnormal PASI had interaction effects with sex for in-hospital mortality (aOR, 1.86; 95% CI, 1.19–2.91 and aOR, 1.38; 95% CI, 0.58–2.99 for male and female, respectively) (p<0.01). @*Conclusion@#Abnormal PASI is associated with increased in-hospital mortality in pediatric trauma patients. The prediction power of PASI for in-hospital mortality was maintained only in male patients.

Impact of Awareness Time Interval on the Effect of Bystander Cardiopulmonary Resuscitation on Out-of-Hospital Cardiac Arrest: A Nationwide Study

Purpose@#The awareness time interval (ATI), the time from the witnessed event to emergency medical service (EMS) activation, is an important factor influencing out-of-hospital cardiac arrest (OHCA) outcomes. Since bystander cardiopulmonary resuscitation (BCPR) is provided after cardiac arrest is recognized, the effect of BCPR may vary depending on ATI delay. We aimed to investigate whether ATI modifies the effect of BCPR on OHCA outcomes. @*Materials and Methods@#A population-based observational study was conducted with EMS-treated witnessed adult (≥18 years) OHCAs between 2013 and 2018. The exposure variable was provision of BCPR. The primary outcome was a good neurological outcome defined as cerebral performance category scale 1or 2 (good CPC). Multivariable logistic regression analysis was conducted using the ATI group (–1, 1–5, 5– min) as the interaction term. @*Results@#Of 34366 eligible OHCAs, 65.5% received BCPR. EMS was activated within 1 min in 45.9%, within 1–5 min in 29.2%, and after 5 min in 24.9% cases. In the adjusted interaction model, compared with no BCPR, a longer ATI resulted in smaller adjusted odds ratios for good CPC in the BCPR group [5.33 (4.17–6.82) for ATI ≤1 min, 5.14 (4.00–6.60) for 1–5 min, and 2.14 (1.63–2.81) for ATI >5 min]. @*Conclusion@#The effect of BCPR on improving the chances for a good neurological outcome decreased as time from collapse to EMS activation increased. The importance of early recognition of OHCA and EMS activation should be emphasized in BCPR training.

Interactions between Sleep Apnea and Coronary Artery Disease on the Incidence of Sudden Cardiac Arrest: A Multi-Center Case-Control Study

Purpose@#Sleep apnea (SA) is a risk factor for coronary artery disease (CAD), and SA and CAD increase the incidence of sudden cardiac arrest (SCA). This study aimed to investigate the effect of SA on the incidence of SCA and explore the effect of varying degrees of SA with or without CAD on the incidence of SCA. @*Materials and Methods@#This prospective multi-center, case-control study was performed using the phase II Cardiac Arrest Pursuit Trial with Unique Registry and Epidemiologic Surveillance (CAPTURES-II) database for SCA cases and community-based controls in Korea. The matching ratio of cases to controls was 1:1, and they were randomly matched within demographics, including age, sex, and residence. The primary variable was a history of SA, and the second variable was a history of CAD. We conducted a conditional logistic regression analysis to estimate the effect of SA and CAD on the SCA risk, and an interaction analysis between SA and CAD. @*Results@#SA was associated with an increased risk of SCA [adjusted odds ratio (AOR) (95% confidence interval, CI): 1.54 (1.16–2.03)], and CAD was associated with an increased risk of SCA [AOR (95% CI): 3.94 (2.50–6.18)]. SA was a risk factor for SCA in patients without CAD [AOR (95% CI): 1.62 (1.21–2.17)], but not in patients with CAD [AOR (95% CI): 0.56 (0.20–1.53)]. @*Conclusion@#In the general population, SA is risk factor for SCA only in patients without CAD. Early medical intervention for SA, especially in populations without pre-existing CAD, may reduce the SCA risk.ClinicalTrials.gov (NCT03700203)

Prehospital intravenous catheter insertion, scene time interval, and their association with fatality in severe trauma patients with hypotension

Objective@#To investigate the association between prehospital intravenous (IV) catheter insertion, scene time interval (STI), and fatality in severe trauma patients with hypotension. @*Methods@#This study used a 2018 nationwide emergency medical services (EMS)-based trauma database. Adult severe trauma patients whose injury severity score was above or equal to 16 and whose initial systolic blood pressure was under 90 mmHg were included. Patients were divided into four groups based on whether a prehospital IV catheter was inserted and STI was within 10 minutes-group 1, IV catheter (+) and STI <10 minutes; group 2, IV catheter (+) and STI ≥10 minutes; group 3, IV catheter (-) and STI <10 minutes; and group 4, IV catheter (-) and STI ≥10 minutes. W-score (additional survivor expected for every 100 patients) was used as the outcome index. @*Results@#Among the 30,034 EMS-treated severe trauma patients, 550 patients were analyzed. Group 1 comprised 289 patients (53%), group 2, 159 (29%), group 3, 65 (12%), and group 4, 37 (6.7%). The case fatality rate was 104 (36%) in group 1, 38 (25%) in group 2, 23 (35%) in group 3, and 11 (30%) in group 4. The W-score (95% confidence interval) was 2.42 (2.38 to 2.99) in group 1, 1.89 (1.83 to 2.90) in group 2, -4.62 (-4.70 to -2.94) in group 3, and -5.41 (-5.52 to -3.03) in group 4. @*Conclusion@#Prehospital IV catheter insertion in severe trauma patients with hypotension is beneficial for survival, and the positive effect was prominent when STI was short.

Changes and their prognostic implications of the National Early Warning Score (NEWS) in interhospital transferred critically ill patients

Objective@#This study aimed to investigate the association between the change in the National Early Warning Score (NEWS) before and after interhospital transport and the survival of critically ill patients transported by critical care transport. @*Methods@#A retrospective analysis of SMICU (Seoul Mobile Intensive Care Unit) transfer records and the National Emergency Department Information System (NEDIS) was conducted. Adult patients who used SMICU from 2016 to 2018 were included. Trauma patients and post-cardiac arrest patients were excluded. The NEWS before departure from the transferring hospital and the NEWS before the arrival at the receiving hospital were extracted, and the difference between both NEWS (△ NEWS) was calculated. The △ NEWS was categorized into three groups: -2 or less, -1 to 1, and 2 or more. The primary outcome was 24-hour post-transport mortality. Multivariable logistic regression was applied to calculate the adjusted odds ratio (AOR) and 95% confidence interval (CI) for the outcomes. @*Results@#Of the total number of 1,837 patients, 1,065 patients were included. △ NEWS were -2 or less in 131 (12.3%), -1 to 1 in 805 (75.6%), and 2 or more in 129 (12.1%) of the patients. The 24-hour mortality rate was 3.1%, 2.9%, and 7.0% in the △ NEWS≤-2, -1≤△ NEWS≤1, and △ NEWS≥2 groups, respectively. Relative to -1≤△ NEWS≤1, the AORs for the 24-hour mortality were 1.11 (95% CI, 0.38-3.29) in △ NEWS≤-2 and 2.56 (95% CI, 1.15-5.70) in △ NEWS≥2. @*Conclusion@#The changes in NEWS in critical care interhospital transport are associated with patient prognosis.

Risk Factors for the Prescription of Ineffective Antiviral Candidates for COVID-19 During the Early Pandemic Period in Korea

Background@#Although the evidence of treatment for coronavirus disease 2019 (COVID-19) changed rapidly, little is known about the patterns of potential pharmacological treatment during the early period of the COVID-19 pandemic in Korea and the risk factors for ineffective prescription. @*Methods@#Using claims data from the Korean National Health Insurance System, this retrospective cohort study included admission episodes for COVID-19 from February to December 2020. Ineffective antiviral prescriptions for COVID-19 were defined as lopinavir/ ritonavir (LPN/r) and hydroxychloroquine (HCQ) prescribed after July 2020, according to the revised National Institute of Health COVID-19 treatment guidelines. Factors associated with ineffective prescriptions, including patient and hospital factors, were identified by multivariate logistic regression analysis. @*Results@#Of the 15,723 COVID-19 admission episodes from February to June 2020, 4,183 (26.6%) included prescriptions of LPN/r, and 3,312 (21.1%) included prescriptions of HCQ.Of the 48,843 admission episodes from July to December 2020, after the guidelines were revised, 2,258 (4.6%) and 182 (0.4%) included prescriptions of ineffective LPN/r and HCQ, respectively. Patient factors independently associated with ineffective antiviral prescription were older age (adjusted odds ratio [aOR] per 10-year increase, 1.17; 95% confidence interval [CI], 1.14–1.20) and severe condition with an oxygen requirement (aOR, 2.49; 95% CI, 2.24–2.77). The prescription of ineffective antiviral drugs was highly prevalent in primary and nursing hospitals (aOR, 40.58; 95% CI, 31.97–51.50), public sector hospitals (aOR, 15.61; 95% CI, 12.76–19.09), and regions in which these drugs were highly prescribed before July 2020 (aOR, 10.65; 95% CI, 8.26–13.74). @*Conclusion@#Ineffective antiviral agents were prescribed to a substantial number of patients during the first year of the COVID-19 pandemic in Korea. Treatment with these ineffective drugs tended to be prolonged in severely ill patients and in primary and public hospitals.

Circulating Vitamin D Level and Risk of Sudden Cardiac Death and Cardiovascular Mortality:A Dose-Response Meta-Analysis of Prospective Studies

Background@#We conducted a comprehensive meta-analysis of prospective cohort studies to analyze the effect of circulating vitamin D level on the risk of sudden cardiac death (SCD) and cardiovascular disease (CVD) mortality. @*Methods@#Prospective cohort studies evaluating the association between circulating vitamin D and risk of SCD and CVD mortality were systematically searched in the PubMed and Embase. Extracted data were analyzed using a random effects model and results were expressed in terms of hazard ratio (HR) and 95% confidence interval (CI). Restricted cubic spline analysis was used to estimate the dose-response relationships. @*Results@#Of the 1,321 records identified using the search strategy, a total of 19 cohort studies were included in the final meta-analysis. The pooled estimate of HR (95% CI) for low vs. high circulating vitamin D level was 1.75 (1.49–2.06) with I 2 value of 30.4%. In subgroup analysis, strong effects of circulating vitamin D were observed in healthy general population (pooled HR, 1.84; 95% CI, 1.43–2.38) and the clinical endpoint of SCD (pooled HRs, 2.68; 95% CI, 1.48– 4.83). The dose-response analysis at the reference level of < 50 nmol/L showed a significant negative association between circulating vitamin D and risk of SCD and CVD mortality. @*Conclusion@#Our meta-analysis of prospective cohort studies showed that lower circulating vitamin D level significantly increased the risk of SCD and CVD mortality.

National Implementation of Emergency Department-Based Followup Program for Suicidal Attempts

Background@#Death by suicide is a major public health problem. To provide multidisciplinary support to patients who attempted suicide, emergency department (ED)-based psychiatric screening and intervention programs were offered. We traced the long-term survival outcome of patients visiting the ED after suicide attempts using the national death certificate registration database. @*Methods@#A retrospective observational study was conducted using a database of patients from “Psychiatric Crisis Response Centers” (PCRC) of 27 EDs between January 2013 and August 2015. Patients who visited the ED after attempting suicide were screened and interviewed by social workers from the PCRC. The database was merged with the national death certificate database to trace the death and cause of death of the patients until December 2018. The characteristics and outcomes were compared based on the patient’s compliance with the follow-up case management program. @*Results@#Of the 12,544 interviewed patients, the data of 9,587 patients were successfully matched with data from the death certificate database. Death by suicide was higher in the noncompliance group (4.5% vs. 12.4%, P < 0.001); however, death caused by factors other than suicide did not differ between groups (4.8% vs. 4.9%, P = 0.906). @*Conclusion@#Suicide resulted in a lower long-term mortality rate among patients who complied with the follow-up case management session in the ED-based brief psychiatric intervention and follow-up program.

Association of transport time interval with neurologic outcome in out-of-hospital cardiac arrest patients without return of spontaneous circulation on scene and the interaction effect according to prehospital airway management

Objective@#This study analyzed the association of transport time interval (TTI) with survival rate and neurologic outcome in out-of-hospital cardiac arrest (OHCA) patients without return of spontaneous circulation (ROSC) and the interaction effect of TTI according to prehospital airway management. @*Methods@#A retrospective observational study based on the nationwide OHCA database from January 2013 to December 2017 was designed. Emergency medical service (EMS)-treated OHCA patients aged ≥18 years were included. TTI was categorized into four groups of quartiles (≤4, 5–7, 8–11, ≥12 minutes). The primary outcome was favorable neurologic outcome at discharge. The secondary outcome was survival to discharge from the hospital. Multivariable logistic regression was used to analyze outcomes according to TTI. A different effect of TTI according to the administration of prehospital EMS advanced airway was evaluated. @*Results@#In total, 83,470 patients were analyzed. Good neurologic recovery decreased as TTI increased (1.0% for TTI ≤4 minutes, 0.9% for TTI 5–7 minutes, 0.6% for TTI 8–11 minutes, and 0.5% for TTI ≥12 minutes; P for trend <0.05). The adjusted odds ratio of prolonged TTI (≥12 minutes) was 0.73 (95% confidence interval, 0.57–0.93; P<0.01) for good neurologic recovery. However, the negative effect of prolonged TTI on neurological outcome was insignificant when advanced airway or entotracheal intubation were performed by EMS providers (adjusted odds ratio, 1.17; 95% confidence interval, 0.42–3.29; P=0.76). @*Conclusion@#EMS TTI was negatively associated with the neurologic outcome of OHCA without ROSC on scene. When advanced airway was performed on scene, TTI was insignificantly associated with the outcome.

Interaction Effects between COVID-19 Outbreak and Community Income Levels on Excess Mortality among Patients Visiting Emergency Departments

Background@#The objective of this study was to examine the effect of the coronavirus disease 2019 (COVID-19) outbreak on excess in-hospital mortality among patients who visited emergency departments (EDs) and to assess whether the excess mortality during the COVID-19 pandemic varies by community income level. @*Methods@#This is a cross-sectional study using the National Emergency Department Information System (NEDIS) database in Korea. The study population was defined as patients who visited all 402 EDs with medical conditions other than injuries between January 27 and May 31, 2020 (after-COVID) and for the corresponding time period in 2019 (before-COVID). The primary outcome was in-hospital mortality. The main exposure was the COVID-19 outbreak, and the interaction variable was county per capita income tax. We calculated the risk-adjusted in-hospital mortality rates by COVID-19 outbreak, as well as the difference-in-difference of risk-adjusted rates between the before-COVID and after-COVID groups according to the county income tax using a multilevel linear regression model with the interaction term. @*Results@#A total of 11,662,167 patients (6,765,717 in before-COVID and 4,896,450 in afterCOVID) were included in the study with a 1.6% crude in-hospital mortality rate. The riskadjusted mortality rate in the after-COVID group was higher than that in the before-COVID group (1.82% vs. 1.50%, difference: 0.31% [0.30 to 0.33]; adjusted odds ratio: 1.22 [1.18 to 1.25]). The excess in-hospital mortality rate of the after-COVID in the lowest quartile group of county income tax was significantly higher than that in the highest quartile group (difference-in-difference: 0.18% (0.14 to 0.23); P-for-interaction: < 0.01). @*Conclusion@#During the COVID-19 pandemic, there was excess in-hospital mortality among patients who visited EDs, and there were disparities in excess mortality depending on community socioeconomic positions.

Interaction Effects between COVID-19 Outbreak and Community Income Levels on Excess Mortality among Patients Visiting Emergency Departments

Background@#The objective of this study was to examine the effect of the coronavirus disease 2019 (COVID-19) outbreak on excess in-hospital mortality among patients who visited emergency departments (EDs) and to assess whether the excess mortality during the COVID-19 pandemic varies by community income level. @*Methods@#This is a cross-sectional study using the National Emergency Department Information System (NEDIS) database in Korea. The study population was defined as patients who visited all 402 EDs with medical conditions other than injuries between January 27 and May 31, 2020 (after-COVID) and for the corresponding time period in 2019 (before-COVID). The primary outcome was in-hospital mortality. The main exposure was the COVID-19 outbreak, and the interaction variable was county per capita income tax. We calculated the risk-adjusted in-hospital mortality rates by COVID-19 outbreak, as well as the difference-in-difference of risk-adjusted rates between the before-COVID and after-COVID groups according to the county income tax using a multilevel linear regression model with the interaction term. @*Results@#A total of 11,662,167 patients (6,765,717 in before-COVID and 4,896,450 in afterCOVID) were included in the study with a 1.6% crude in-hospital mortality rate. The riskadjusted mortality rate in the after-COVID group was higher than that in the before-COVID group (1.82% vs. 1.50%, difference: 0.31% [0.30 to 0.33]; adjusted odds ratio: 1.22 [1.18 to 1.25]). The excess in-hospital mortality rate of the after-COVID in the lowest quartile group of county income tax was significantly higher than that in the highest quartile group (difference-in-difference: 0.18% (0.14 to 0.23); P-for-interaction: < 0.01). @*Conclusion@#During the COVID-19 pandemic, there was excess in-hospital mortality among patients who visited EDs, and there were disparities in excess mortality depending on community socioeconomic positions.

Heat, heat waves, and out-of-hospital cardiac arrest.

OBJECTIVE: Cardiac arrest is one of the common presentations of cardiovascular disorders and a leading cause of death. There are limited data on the relationship between out-of-hospital cardiac arrest (OHCA) and ambient temperatures, specifically extreme heat. This study investigated how heat and heat waves affect the occurrence of OHCA. METHODS: Seven major cities in Korea with more than 1 million residents were included in this study. A heat wave was defined as a daily mean temperature above the 98th percentile of the yearly distribution for at least two consecutive days. RESULTS: A total of 50,318 OHCAs of presumed cardiac origin were identified from the nationwide emergency medical service database between 2006 and 2013. Ambient temperature and OHCA had a J-shaped relationship with a trough at 28°C. Heat waves were shown to be associated with a 14-% increase in the risk of OHCA. Adverse effects were apparent from the beginning of each heat wave period and slightly increased during its continuation. Excess OHCA events during heat waves occurred between 3PM and 5PM. Subgroup analysis showed that those 65years or older were significantly more susceptible to heat waves. CONCLUSIONS: Ambient temperature and OHCA had a J-shaped relationship. The risk of OHCA was significantly increased with heat waves. Excess OHCA events primarily occurred during the afternoon when the temperature was high. We found that the elderly were more susceptible to the deleterious effects of heat waves.

Association between the number of prehospital defibrillation attempts and neurologic outcomes in out-of-hospital cardiac arrest patients without on-scene return of spontaneous circulation

Objective@#Delivery of prehospital defibrillation for shockable rhythms by emergency medical service providers is crucial for successful resuscitation in out-of-hospital cardiac arrest (OHCA) patients. The optimal range of prehospital defibrillation attempts for refractory shockable rhythms is unknown. This study evaluated the association between the number of prehospital defibrillation attempts and neurologic outcomes in OHCA patients. @*Methods@#A retrospective observational study was conducted using the nationwide OHCA registry. Adult OHCA patients who were treated by emergency medical service providers due to presumed cardiac origin with initial shockable rhythm were enrolled from 2013 to 2016. The final analysis was performed on patients without on-scene return of spontaneous circulation. The number of prehospital defibrillation attempts was categorized as follows: 2–3, 4–5, and ≥6 attempts. The primary outcome was a good neurologic recovery at hospital discharge. Multivariate logistic regression analysis was performed to evaluate the association between neurologic outcomes and the number of prehospital defibrillation attempts. @*Results@#A total of 4,513 patients were included in the final analysis. The numbers of patients for whom 2–3, 4–5, and ≥6 defibrillation attempts were made were 2,720 (60.3%), 1,090 (24.2%), and 703 (15.5%), respectively. Poorer outcomes were associated with ≥6 defibrillation attempts: survival to hospital discharge (adjusted odds ratio, 0.38; 95% confidence interval, 0.21–0.65) and good neurologic recovery (adjusted odds ratio, 0.42; 95% confidence interval, 0.21–0.84). @*Conclusion@#Six or more prehospital defibrillation attempts were associated with poorer neurologic outcomes in OHCA patients with an initial shockable rhythm who were unresponsive to on-scene defibrillation and resuscitation.

Association between the number of prehospital defibrillation attempts and neurologic outcomes in out-of-hospital cardiac arrest patients without on-scene return of spontaneous circulation

Objective@#Delivery of prehospital defibrillation for shockable rhythms by emergency medical service providers is crucial for successful resuscitation in out-of-hospital cardiac arrest (OHCA) patients. The optimal range of prehospital defibrillation attempts for refractory shockable rhythms is unknown. This study evaluated the association between the number of prehospital defibrillation attempts and neurologic outcomes in OHCA patients. @*Methods@#A retrospective observational study was conducted using the nationwide OHCA registry. Adult OHCA patients who were treated by emergency medical service providers due to presumed cardiac origin with initial shockable rhythm were enrolled from 2013 to 2016. The final analysis was performed on patients without on-scene return of spontaneous circulation. The number of prehospital defibrillation attempts was categorized as follows: 2–3, 4–5, and ≥6 attempts. The primary outcome was a good neurologic recovery at hospital discharge. Multivariate logistic regression analysis was performed to evaluate the association between neurologic outcomes and the number of prehospital defibrillation attempts. @*Results@#A total of 4,513 patients were included in the final analysis. The numbers of patients for whom 2–3, 4–5, and ≥6 defibrillation attempts were made were 2,720 (60.3%), 1,090 (24.2%), and 703 (15.5%), respectively. Poorer outcomes were associated with ≥6 defibrillation attempts: survival to hospital discharge (adjusted odds ratio, 0.38; 95% confidence interval, 0.21–0.65) and good neurologic recovery (adjusted odds ratio, 0.42; 95% confidence interval, 0.21–0.84). @*Conclusion@#Six or more prehospital defibrillation attempts were associated with poorer neurologic outcomes in OHCA patients with an initial shockable rhythm who were unresponsive to on-scene defibrillation and resuscitation.

Modification and Validation of a Complaint-Oriented Emergency Department Triage System:A Multicenter Observational Study

Purpose@#The objective of this study was to modify and validate an emergency department (ED) triage system with improved prediction performance on hospital outcomes by modifying the Korean Triage and Acuity Scale (KTAS). @*Materials and Methods@#We performed a retrospective observational study at three academic universities in South Korea. The KTAS code, determined by the chief complaint and the selected modifier of a patient, was used to derive the Modified KTAS (MKTAS). We calculated the area under the receiver operating characteristics curve (AUC) and the test characteristics to evaluate the performance of MKTAS to predict hospital mortality, critical outcome, and admission. @*Results@#A total of 272402 and 128831 ED visits were used for the derivation and validation of MKTAS, respectively. Compared to KTAS, MKTAS had significantly higher AUC values for the prediction of hospital mortality [MKTAS 0.826 (0.818–0.835) vs. KTAS 0.794 (0.784–0.803)], critical outcome [MKTAS 0.836 (0.830–0.841) vs. 0.798 (0.792–0.804)], and admission [MKTAS 0.725 (0.723– 0.728) vs. KTAS 0.685 (0.682–0.688)]. The sensitivity for predicting hospital mortality and critical outcome, as well as the specificity for predicting admission, were significantly improved. @*Conclusion@#MKTAS was derived by modifying the KTAS, and then validated. Compared with KTAS, MKTAS showed better discriminating ability to predict hospital outcomes. Continuous efforts to evaluate and modify widely used triage systems are required to improve their performance.

Low serum cholesterol level as a risk factor for out-of-hospital cardiac arrest: a case-control study

Objective@#We aimed to identify the association between low serum total cholesterol levels and the risk of out-of-hospital cardiac arrest (OHCA). @*Methods@#This case-control study was performed using datasets from the Cardiac Arrest Pursuit Trial with Unique Registration and Epidemiologic Surveillance (CAPTURES) project and the Korea National Health and Nutrition Examination Survey (KNHANES). Cases were defined as emergency medical service-treated adult patients who experienced OHCA with a presumed cardiac etiology from the CAPTURES project dataset. Four controls from the KNHANES dataset were matched to each case based on age, sex, and county. Multivariable conditional logistic regression analysis was conducted to evaluate the effect of total cholesterol levels on OHCA. @*Results@#A total of 607 matched case-control pairs were analyzed. We classified total cholesterol levels into six categories (<148, 148-166.9, 167-189.9, 190-215.9, 216.237.9, and ≥238 mg/dL) according to the distribution of total cholesterol levels in the KNHANES dataset. Subjects with a total cholesterol level of 167-189.9 mg/dL (25th.49th percentile of the KNHANES dataset) were used as the reference group. In both the adjusted models and sensitivity analysis, a total cholesterol level of <148 mg/dL was significantly associated with OHCA (adjusted odds ratio [95% confidence interval], 6.53 [4.47.9.56]). @*Conclusion@#We identified an association between very-low total cholesterol levels and an increased risk of OHCA in a large, community-based population. Future prospective studies are needed to better understand how a low lipid profile is associated with OHCA.

Development of a modified trauma and injury severity score to predict disability in acute trauma patients

Objective@#The Trauma and Injury Severity Score (TRISS) has been used to predict trauma patient mortality and to assess the quality of trauma care systems. The goal of this investigation was to develop a modified trauma-related injury severity score (termed the TRISS-D) for predicting disability in acute trauma patients. @*Methods@#We used data collected by emergency medical services and entered into the Korea Centers for Disease Control and Prevention severe trauma database. The TRISS-D was based on age category (0–14, 15–54, ≥55 years), the Revised Trauma Score, and the Injury Severity Score. The outcome measures were severe disability and worsening disability. Worsening disability was defined as a lower Glasgow Outcome Scale score at hospital discharge than before the traumatic incident. Two types of cases were examined: those with penetrating or blunt injuries (group 1) and those with severe head injuries (group 2). We assessed the discriminatory power of the TRISS-D by calculating the area under a receiver operating characteristic curve (AUROC). @*Results@#The database comprised 14,791 patients; overall, 3,757 (25%) had severe disability and 6,018 (41%) had worsening disability. For severe disability, the AUROC (95% confidence interval) for the TRISS-D was 0.948 (0.944–0.952) in group 1 and 0.950 (0.946–0.954) in group 2. The corresponding values for worsening disability were 0.810 (0.803–0.817) and 0.816 (0.809–0.823), respectively. @*Conclusion@#The TRISS-D showed excellent discriminatory power for severe disability and very good discriminatory power for worsening disability.

Development of a modified trauma and injury severity score to predict disability in acute trauma patients

Objective@#The Trauma and Injury Severity Score (TRISS) has been used to predict trauma patient mortality and to assess the quality of trauma care systems. The goal of this investigation was to develop a modified trauma-related injury severity score (termed the TRISS-D) for predicting disability in acute trauma patients. @*Methods@#We used data collected by emergency medical services and entered into the Korea Centers for Disease Control and Prevention severe trauma database. The TRISS-D was based on age category (0–14, 15–54, ≥55 years), the Revised Trauma Score, and the Injury Severity Score. The outcome measures were severe disability and worsening disability. Worsening disability was defined as a lower Glasgow Outcome Scale score at hospital discharge than before the traumatic incident. Two types of cases were examined: those with penetrating or blunt injuries (group 1) and those with severe head injuries (group 2). We assessed the discriminatory power of the TRISS-D by calculating the area under a receiver operating characteristic curve (AUROC). @*Results@#The database comprised 14,791 patients; overall, 3,757 (25%) had severe disability and 6,018 (41%) had worsening disability. For severe disability, the AUROC (95% confidence interval) for the TRISS-D was 0.948 (0.944–0.952) in group 1 and 0.950 (0.946–0.954) in group 2. The corresponding values for worsening disability were 0.810 (0.803–0.817) and 0.816 (0.809–0.823), respectively. @*Conclusion@#The TRISS-D showed excellent discriminatory power for severe disability and very good discriminatory power for worsening disability.