Association between out-of-hospital cardiac arrest quality indicator and prehospital management and clinical outcomes for major trauma.

INTRODUCTION: It is unclear whether emergency medical service (EMS) agencies with good out-of-hospital cardiac arrest (OHCA) quality indicators also perform well in treating other emergency conditions. We aimed to evaluate the association of an EMS agency's non-traumatic OHCA quality indicators with prehospital management processes and clinical outcomes of major trauma. METHODS: This retrospective cross-sectional study analyzed data from registers of nationwide, population-based OHCA (adult EMS-treated non-traumatic OHCA patients from 2017 to 2018) and major trauma (adult, EMS-treated, and injury severity score ≥16 trauma patients in 2018) in South Korea. We developed a prehospital ROSC prediction model to categorize EMS agencies into quartiles (Q1-Q4) based on the observed-to-expected (O/E) ROSC ratio for each EMS agency. We evaluated the national EMS protocol compliance of on-scene management according to O/E ROSC ratio quartile. The association between O/E ROSC ratio quartiles and trauma-related early mortality was determined in a multi-level logistic regression model by adjusted odds ratios (OR) and 95 % confidence intervals (95 % CI). RESULTS: Among 30,034 severe trauma patients, 4,836 were analyzed. Patients in Q4 showed the lowest early mortality rate (5.6 %, 5.5 %, 4.8 %, and 3.4 % in Q1, Q2, Q3, and Q4, respectively). In groups Q1 to Q4, increasing compliance with the national EMS on-scene management protocol (trauma center transport, basic airway management for patients with altered mentality, spinal motion restriction for patients with spinal injury, and intravenous access for patients with hypotension) was observed (p for trend <0.05). Multivariable multi-level logistic regression analysis showed significantly lower early mortality in Q4 than in Q1 (adjusted OR [95 % CI] 0.56 [0.35-0.91]). CONCLUSION: Major trauma patients managed by EMS agencies with high success rates in achieving prehospital ROSC in non-traumatic OHCA were more likely to receive protocol-based care and exhibited lower early mortality.

Seat belt use and cardiac arrest immediately after motor vehicle collision: Nationwide observational study.

Objective: Motor vehicle collisions (MVCs) are known to cause traumatic cardiac arrest; it is unclear whether seat belts prevent this. This study aimed to evaluate the association between seat belt use and immediate cardiac arrest in cases of MVCs. Method: This cross-sectional observational study used data from a nationwide EMS-based severe trauma registry in South Korea. The sample comprised adult patients with EMS-assessed severe trauma due to MVCs between 2018 and 2019. The primary, secondary, and tertiary outcomes were immediate cardiac arrest, in-hospital mortality, and death or severe disability, respectively. We calculated the adjusted odds ratios (AORs) of immediate cardiac arrest with seat belt use after adjusting for potential confounders. Results: Among the 8178 eligible patients, 6314 (77.2 %) and 1864 (29.5 %) were wearing and not wearing seat belts, respectively. Immediate cardiac arrest, mortality, and death/severe disability rates were higher in the "no seat belt use" group than in the "seat belt use" group (9.4 % vs. 4.0 %, 12.4 % vs. 6.2 %, 17.7 % vs. 9.9 %, respectively; p < 0.001). The former group was more likely to experience immediate cardiac arrest (AOR [95 %CI]: 3.29 [2.65-4.08]), in-hospital mortality (AOR [95 %CI]: 2.72 [2.26-3.27]), and death or severe disability (AOR [95 %CI]: 2.40 [2.05-2.80]). Conclusion: There was an association between wearing seat belts during MVCs and a reduced risk of immediate cardiac arrest.

Effects of Transport to Trauma Centers on Survival Outcomes Among Severe Trauma Patients in Korea: Nationwide Age-Stratified Analysis.

BACKGROUND: Previous studies showed that the prognosis for severe trauma patients is better after transport to trauma centers compared to non-trauma centers. However, the benefit from transport to trauma centers may differ according to age group. The aim of this study was to compare the effects of transport to trauma centers on survival outcomes in different age groups among severe trauma patients in Korea. METHODS: Cross-sectional study using Korean national emergency medical service (EMS) based severe trauma registry in 2018-2019 was conducted. EMS-treated trauma patients whose injury severity score was above or equal to 16, and who were not out-of-hospital cardiac arrest or death on arrival were included. Patients were classified into 3 groups: pediatrics (age < 19), working age (age 19-65), and elderly (age > 65). The primary outcome was in-hospital mortality. Multivariable logistic regression analysis was conducted to evaluate the effect of trauma center transport on outcome after adjusting of age, sex, comorbidity, mechanism of injury, Revised Trauma Score, and Injury Severity Score. All analysis was stratified according to the age group, and subgroup analysis for traumatic brain injury was also conducted. RESULTS: Overall, total of 10,511 patients were included in the study, and the number of patients in each age group were 488 in pediatrics, 6,812 in working age, and 3,211 in elderly, respectively. The adjusted odds ratio (95% confidence interval [CI]) of trauma center transport on in-hospital mortality from were 0.76 (95% CI, 0.43-1.32) in pediatrics, 0.78 (95% CI, 0.68-0.90) in working age, 0.71(95% CI, 0.60-0.85) in elderly, respectively. In subgroup analysis of traumatic brain injury, the benefit from trauma center transport was observed only in elderly group. CONCLUSION: We found out trauma centers showed better clinical outcomes for adult and elderly groups, excluding the pediatric group than non-trauma centers. Further research is warranted to evaluate and develop the response system for pediatric severe trauma patients in Korea.

Automatic Mechanical Ventilation vs Manual Bag Ventilation During CPR: A Pilot Randomized Controlled Trial.

BACKGROUND: There is insufficient evidence supporting the theory that mechanical ventilation can replace the manual ventilation method during CPR. RESEARCH QUESTION: Is using automatic mechanical ventilation feasible and comparable to the manual ventilation method during CPR? STUDY DESIGN AND METHODS: This pilot randomized controlled trial compared automatic mechanical ventilation (MV) and manual bag ventilation (BV) during CPR of out-of-hospital cardiac arrest (OHCA). Patients with medical OHCA arriving at the ED were randomly assigned to two groups: an MV group using a mechanical ventilator and a BV group using Ambu-bag. Primary outcome was any return-of-spontaneous circulation (ROSC). Secondary outcomes were changes of arterial blood gas analysis results during CPR. Tidal volume, minute volume, and peak airway pressure were also analyzed. RESULTS: A total of 60 patients were enrolled, and 30 patients were randomly assigned to each group. There were no statistically significant differences in basic characteristics of OHCA patients between the two groups. The rate of any ROSC was 56.7% in the MV group and 43.3% in the BV group, indicating no significant (P = .439) difference between the two groups. There were also no statistically significant differences in changes of PH, Pco2, Po2, HCO3, or lactate levels during CPR between the two groups (P values = .798, 0.249, .515, .876, and .878, respectively). Significantly lower VT (P < .001) and minute volume (P = .009) were observed in the MV group. INTERPRETATION: In this pilot trial, the use of MV instead of BV during CPR was feasible and could serve as a viable alternative. A multicenter randomized controlled trial is needed to create sufficient evidence for ventilation guideline during CPR. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov; No.: NCT05550454; URL: www. CLINICALTRIALS: gov.

Establishing the Korean Out-of-Hospital cardiac arrest registry (KOHCAR).

Background: The Korean out-of-hospital cardiac arrest registry (KOHCAR) serves as the basis for a chain of survival monitoring and quality improvement programs for out-of-hospital cardiac arrest (OHCA). This study describes the development history and current status of KOHCAR. Methods/design: The KOHCAR, initiated in 2008, is a population-based OHCA registry that captures all emergency medical service (EMS)-assessed OHCA cases, regardless of etiology. The KOHCAR represents complete nationwide data and aligns with South Korea's comprehensive plan for cardiovascular disease, which has a legal basis. The KOHCAR is a collaboration between the National Fire Agency (NFA) and the Korea Disease Control and Prevention Agency (KDCA). The NFA identifies OHCA patients and provides prehospital information after integrating various EMS records, whereas the KDCA collects hospital information and clinical outcomes through a medical record review. Comprehensive Utstein variables, including patient and arrest characteristics, prehospital and hospital management, and survival outcomes, were collected. Discussion: The KOHCAR has significantly contributed to improving OHCA survival rates in South Korea; however, the COVID-19 pandemic has posed challenge. To address the post-pandemic survival rate decline, there is a need to enhance data utilization, expand data sources, and tailor communication with diverse stakeholders.

Association between Case Volumes of Extracorporeal Life Support and Clinical Outcome in Out-of-Hospital Cardiac Arrest.

AIM: Extracorporeal life support (ECLS) for out-of-hospital cardiac arrest (OHCA) is increasing. There is little evidence identifying the association between hospital ECLS case volumes and outcomes in different populations receiving ECLS or conventional cardiopulmonary resuscitation (CPR). The goal of this investigation was to identify the association between ECLS case volumes and clinical outcomes of OHCA patients. METHODS: This cross-sectional observational study used the National OHCA Registry for adult OHCA cases in Seoul, Korea between January 2015 and December 2019. If the ECLS volume during the study period was >20, the institution was defined as a high-volume ECLS center. Others were defined as low-volume ECLS centers. Outcomes were good neurologic recovery (cerebral performance category 1 or 2) and survival to discharge. We performed multivariate logistic regression and interaction analyses to assess the association between case volume and clinical outcome. RESULTS: Of the 17,248 OHCA cases, 3,731 were transported to high-volume centers. Among the patients who underwent ECLS, those at high-volume centers had a higher neurologic recovery rate than those at low-volume centers (17.0% vs. 12.0%), and the adjusted OR for good neurologic recovery was 2.22 (95% confidence interval (CI): 1.15-4.28) in high-volume centers compared to low-volume centers. For patients who received conventional CPR, high-volume centers also showed higher survival-to-discharge rates (adjusted OR of 1.16, 95%CI: 1.01-1.34). CONCLUSIONS: High-volume ECLS centers showed better neurological recovery in patients who underwent ECLS. High-volume centers also had better survival-to-discharge rates than low-volume centers for patients not receiving ECLS.

Effect of first epinephrine administration time on cerebral perfusion pressure and cortical cerebral blood flow in a porcine cardiac arrest model.

OBJECTIVE: The optimal time for epinephrine administration and its effects on cerebral blood flow (CBF) and microcirculation remain controversial. This study aimed to assess the effect of the first administration of epinephrine on cerebral perfusion pressure (CePP) and cortical CBF in porcine cardiac arrest model. METHODS: After 4 min of untreated ventricular fibrillation, eight of 24 swine were randomly assigned to the early, intermediate, and late groups. In each group, epinephrine was administered intravenously at 5, 10, and 15 min after cardiac arrest induction. CePP was calculated as the difference between the mean arterial pressure and intracranial pressure. Cortical CBF was measured using a laser Doppler flow probe. The outcomes were CePP and cortical CBF measured continuously during cardiopulmonary resuscitation (CPR). Mean CePP and cortical CBF were compared using analysis of variance and a linear mixed model. RESULTS: The mean CePP was significantly different between the groups at 6-11 min after cardiac arrest induction. The mean CePP in the early group was significantly higher than that in the intermediate group at 8-10 min and that in the late group at 6-9 min and 10-11 min. The mean cortical CBF was significantly different between the groups at 9-11 min. The mean cortical CBF was significantly higher in the early group than in the intermediate and late group at 9-10 min. CONCLUSION: Early administration of epinephrine was associated with improved CePP and cortical CBF compared to intermediate or late administration during the early period of CPR.

Mask R-CNN based multiclass segmentation model for endotracheal intubation using video laryngoscope.

Objective: Endotracheal intubation (ETI) is critical to secure the airway in emergent situations. Although artificial intelligence algorithms are frequently used to analyze medical images, their application to evaluating intraoral structures based on images captured during emergent ETI remains limited. The aim of this study is to develop an artificial intelligence model for segmenting structures in the oral cavity using video laryngoscope (VL) images. Methods: From 54 VL videos, clinicians manually labeled images that include motion blur, foggy vision, blood, mucus, and vomitus. Anatomical structures of interest included the tongue, epiglottis, vocal cord, and corniculate cartilage. EfficientNet-B5 with DeepLabv3+, EffecientNet-B5 with U-Net, and Configured Mask R-Convolution Neural Network (CNN) were used; EffecientNet-B5 was pretrained on ImageNet. Dice similarity coefficient (DSC) was used to measure the segmentation performance of the model. Accuracy, recall, specificity, and F1 score were used to evaluate the model's performance in targeting the structure from the value of the intersection over union between the ground truth and prediction mask. Results: The DSC of tongue, epiglottis, vocal cord, and corniculate cartilage obtained from the EfficientNet-B5 with DeepLabv3+, EfficientNet-B5 with U-Net, and Configured Mask R-CNN model were 0.3351/0.7675/0.766/0.6539, 0.0/0.7581/0.7395/0.6906, and 0.1167/0.7677/0.7207/0.57, respectively. Furthermore, the processing speeds (frames per second) of the three models stood at 3, 24, and 32, respectively. Conclusions: The algorithm developed in this study can assist medical providers performing ETI in emergent situations.

The Impact of the COVID-19 Outbreak on Emergency Medical Service: An Analysis of Patient Transportations and Time Intervals.

BACKGROUND: This study aimed to investigate the impact of the coronavirus disease 2019 (COVID-19) outbreak on the Emergency Medical Service (EMS) system in South Korea. The study focused on the differences in EMS time intervals following the COVID-19 outbreak, particularly for patients with fever. METHODS: A retrospective analysis of EMS patient transportation data from 2017 to 2022 was conducted using the national EMS database. RESULTS: Starting from the year 2020, coinciding with the COVID-19 outbreak, all EMS time intervals experienced an increase. For the years 2017 to 2022, the mean response time interval values were 8.6, 8.6, 8.6, 10.2, 12.8, and 11.4 minutes, and the mean scene time interval values were 7.1, 7.2, 7.4, 9.0, 9.8, and 10.9 minutes. The mean transport time interval (TTI) values were 12.1, 12.3, 12.4, 14.2, 16.9, and 16.2 minutes, and the mean turnaround time interval values were 27.6, 27.9, 28.7, 35.2, 42.0, and 43.1 minutes. Fever (≥ 37.5°C) patients experienced more pronounced prolongations in EMS time intervals compared to non-fever patients and had a higher probability of being non-transported. The mean differences in TTI between fever and non-fever patients were 0.8, 0.8, 0.8, 4.3, 4.8, and 3.2 minutes, respectively, from 2017 to 2022. Furthermore, the odds ratios for fever patients being transported to the emergency department were 2.7, 2.9, 2.8, 1.1, 0.8, and 0.7, respectively, from 2017 to 2022. CONCLUSION: The study findings highlight the significant impact of the COVID-19 outbreak on the EMS system and emphasize the importance of ongoing monitoring to evaluate the burden on the EMS system.

Measurement of level of consciousness by AVPU scale assessment system based on automated video and speech recognition technology.

OBJECTIVE: To develop an alert/verbal/painful/unresponsive (AVPU) scale assessment system based on automated video and speech recognition technology (AVPU-AVSR) that can automatically assess a patient's level of consciousness and evaluate its performance through clinical simulation. METHODS: We developed an AVPU-AVSR system with a whole-body camera, face camera, and microphone. The AVPU-AVSR system automatically extracted essential audiovisual features to assess the AVPU score from the recorded video files. Arm movement, pain stimulus, and eyes-open state were extracted using a rule-based approach using landmarks estimated from pre-trained pose and face estimation models. Verbal stimuli were extracted using a pre-trained speech-recognition model. Simulations of a physician examining the consciousness of 12 simulated patients for 16 simulation scenarios (4 for each of "Alert", "Verbal", "Painful", and "Unresponsive") were conducted under the AVPU-AVSR system. The accuracy, sensitivity, and specificity of the AVPU-AVSR system were assessed. RESULTS: A total of 192 cases with 12 simulated patients were assessed using the AVPU-AVSR system with a multi-class accuracy of 0.95 (95% confidence interval [CI] (0.92-0.98). The sensitivity and specificity (95% CIs) for detecting impaired consciousness were 1.00 (0.97-1.00) and 0.88 (0.75-0.95), respectively. The sensitivity and specificity of each extracted feature ranged from 0.88 to 1.00 and 0.98 to 1.00. CONCLUSIONS: The AVPU-AVSR system showed good accuracy in assessing consciousness levels in a clinical simulation and has the potential to be implemented in clinical practice to automatically assess mental status.

Prehospital National Early Warning Score as a predictor of massive transfusion in adult trauma patients.

BACKGROUND: Previous studies have shown that an elevated prehospital National Early Warning Score (preNEWS) is associated with increased levels of adverse outcomes in patients with trauma. However, whether preNEWS is a predictor of massive transfusion (MT) in patients with trauma is currently unknown. This study investigated the accuracy of preNEWS in predicting MT and hospital mortality among trauma patients. METHODS: We analyzed adult trauma patients who were treated and transported by emergency medical services (EMS) between January 2018 and December 2019. The main exposure was the preNEWS calculated for the scene. The primary outcome was the predictive ability for MT, and the secondary outcome was 24 h mortality. We compared the prognostic performance of preNEWS with the shock index, modified shock index, and reverse shock index, and reverse shock index multiplied by Glasgow Coma Scale in the prehospital setting. RESULTS: In total, 41,852 patients were included, and 1456 (3.5%) received MT. preNEWS showed the highest area under the receiver operating characteristic (AUROC) curve for predicting MT (0.8504; 95% confidence interval [CI], 0.840-0.860) and 24 h mortality (AUROC 0.873; 95% CI, 0.863-0.883). The sensitivity of preNEWS for MT was 0.755, and the specificity of preNEWS for MT was 0.793. All indicies had a high negative predictive value and low positive predictive value. CONCLUSION: preNEWS is a useful, rapid predictor for MT and 24 h mortality. Calculation of preNEWS would be helpful for making the decision at the scene such as transfer straightforward to trauma center and advanced treatment.

Interaction effects between insomnia and depression on risk of out-of-hospital cardiac arrest: Multi-center study.

BACKGROUND: Insomnia and depression have been known to be risk factors of several diseases, including coronary heart disease. We hypothesized that insomnia affects the out-of-hospital cardiac arrest (OHCA) incidence, and these effects may vary depending on whether it is accompanied by depression. This study aimed to determine the association between insomnia and OHCA incidence and whether the effect of insomnia is influenced by depression. METHODS: This prospective multicenter case-control study was performed using Phase II Cardiac Arrest Pursuit Trial with Unique Registration and Epidemiology Surveillance (CAPTURES-II) project database for OHCA cases and community-based controls in Korea. The main exposure was history of insomnia. We conducted conditional logistic regression analysis to estimate the effect of insomnia on the risk of OHCA incidence and performed interaction analysis between insomnia and depression. Finally, subgroup analysis was conducted in the patients with insomnia. RESULTS: Insomnia was not associated with increased OHCA risk (0.95 [0.64-1.40]). In the interaction analysis, insomnia interacted with depression on OHCA incidence in the young population. Insomnia was associated with significantly higher odds of OHCA incidence (3.65 [1.29-10.33]) in patients with depression than in those without depression (0.84 [0.59-1.17]). In the subgroup analysis, depression increased OHCA incidence only in patients who were not taking insomnia medication (3.66 [1.15-11.66]). CONCLUSION: Insomnia with depression is a risk factor for OHCA in the young population. This trend was maintained only in the population not consuming insomnia medication. Early and active medical intervention for patients with insomnia may contribute to lowering the risk of OHCA.

Analysis of Trauma Characteristics Between the Older and Younger Adult Patient from the Pan Asian Trauma Outcome Study Registry (PATOS).

OBJECTIVE: Asia is experiencing a demographic shift toward an aging population at an unrivaled rate. This can influence the characteristics and outcomes of trauma. We aim to examine different characteristics of older adult trauma patients compared to younger adult trauma patients and describe factors that affect the outcomes in Asian countries. METHODS: This is a retrospective, international, multicenter study of trauma across participating centers in the Pan Asian Trauma Outcome Study (PATOS) registry, which included trauma cases aged ≥18 years, brought to the emergency department (ED) by emergency medical services (EMS) from October 2015 to November 2018. Data of older adults (≥65 years) and younger adults (<65 years) were analyzed and compared. The primary outcome measure was in-hospital mortality, and secondary outcomes were disability at discharge and hospital and intensive care unit (ICU) length of stays. RESULTS: Of 39,804 trauma patients, 10,770 (27.1%) were older adults. Trauma occurred more among older adult women (54.7% vs 33.2%, p < 0.001). Falls were more frequent in older adults (66.3% vs 24.9%, p < 0.001) who also had higher mean Injury Severity Score (ISS) compared to the younger adult trauma patient (5.4 ± 6.78 vs 4.76 ± 8.60, p < 0.001). Older adult trauma patients had a greater incidence of poor Glasgow Outcome Scale (GOS) (13.4% vs 4.1%, p < 0.001), higher hospital mortality (1.5% vs 0.9%, p < 0.001) and longer median hospital length of stay (12.8 vs 9.8, p < 0.001). Multiple logistic regression revealed age (adjusted odds ratio [AOR] 1.06, 95%CI 1.02-1.04, p < 0.001), male sex (AOR 1.60, 95%CI 1.04-2.46, p = 0.032), head and face injuries (AOR 3.25, 95%CI 2.06-5.11, p < 0.001), abdominal and pelvic injuries (AOR 2.78, 95%CI 1.48-5.23, p = 0.002), cardiovascular (AOR 2.71, 95%CI 1.40-5.22, p = 0.003), pulmonary (AOR 3.13, 95%CI 1.30-7.53, p = 0.011) and cancer (AOR 2.03, 95%CI 1.02-4.06, p = 0.045) comorbidities, severe ISS (AOR 2.06, 95%CI 1.23-3.45, p = 0.006), and Glasgow Coma Scale (GCS) ≤8 (AOR 12.50, 95%CI 6.95-22.48, p < 0.001) were significant predictors of hospital mortality. CONCLUSIONS: Older trauma patients in the Asian region have a higher mortality rate than their younger counterparts, with many significant predictors. These findings illustrate the different characteristics of older trauma patients and their potential to influence the outcome. Preventive measures for elderly trauma should be targeted based on these factors.

Evaluation of Socioeconomic Position and Survival After Out-of-Hospital Cardiac Arrest in Korea Using Structural Equation Modeling.

Importance: The association between low socioeconomic position (SEP) and poor survival after out-of-hospital cardiac arrest (OHCA) has not been thoroughly investigated. Objectives: To evaluate the association between individual SEP and survival after OHCA and to identify any mediating pathways using structural equation modeling (SEM). Design, Setting, and Participants: This is a retrospective cohort study that used data collected from January 2013 to December 2019. Participants were adults with OHCA with a presumed cardiac etiology. The study was conducted in Korea, which has a universal health insurance system. Data were analyzed from January 2022 to February 2023. Exposures: Individual SEP was measured by insurance type (National Health Insurance [NHI] and medical aid [MA]) and premiums. SEP was categorized into 5 groups, in which NHI beneficiaries were divided into quartiles (Q1, highest quartile; Q4, lowest quartile), and MA was the lowest SEP group. Main Outcomes and Measures: The primary outcome was survival to discharge. The association between SEP and OHCA survival was examined using multivariable logistic regression, and mediating factors were identified using SEM. Results: A total of 121 516 patients (median [IQR] age, 73 [60-81] years; 43 912 [36.1%] female patients) were included. Compared with the NHI Q1 group, individuals with lower SEP had lower odds of survival to discharge. The adjusted odds ratios of survival to discharge were 0.97 (95% CI, 0.94-1.00), 0.88 (95% CI, 0.85-0.91), 0.91 (95% CI, 0.88-0.94), and 0.53 (95% CI, 0.50-0.56) for the NHI Q2, NHI Q3, NHI Q4, and MA groups, respectively. Several factors were found to mediate the association of SEP and survival in the total study population, with mediating proportions of 15.1% (95% CI, 11.8%-18.4%) for witnessed status, 4.8% (95% CI, 3.5%-6.0%) for bystander cardiopulmonary resuscitation provision, 41.8% (95% CI, 35.4%-48.1%) for initial rhythm, and 9.4% (95% CI, 7.4%-11.4%) for emergency department level. Among patients who survived to hospital admission, the mediation proportions were 11.8% (95% CI, 6.7%-16.9%) for witnessed status, 3.7% (95% CI, 1.3%-6.1%) for bystander cardiopulmonary resuscitation provision, 56.2% (95% CI, 41.0%-71.4%) for initial rhythm, 10.7% (95% CI, 6.1%-15.3%) for emergency department level, 20.2% (95% CI, 14.0%-26.5%) for coronary angiography, and 4.2% (95% CI, 2.2%-6.1%) for targeted temperature management. Conclusions and Relevance: In this cohort study of patients with OHCA, lower individual SEP was significantly associated with lower survival to discharge. Potentially modifiable mediators can be targeted for public health interventions to reduce disparities in survival among patients with OHCA of different SEP.

Association between the relationship of bystander and neurologic recovery in pediatric out-of-hospital cardiac arrest.

AIM: This study aimed to evaluate whether the relationship between bystanders and victims is associated with neurological outcomes in paediatric out-of-hospital cardiac arrest (OHCA). METHODS: This cross-sectional, retrospective, observational study included patients with non-traumatic paediatric OHCA undergoing emergency medical service treatment between 2014 and 2021. The relationship between bystanders and patients was categorized into first responder, family, and layperson groups. The primary outcome was good neurological recovery. Further sensitivity analyses were conducted subcategorizing the cohort into four groups: first responder, family, friends or colleagues, and layperson, or two groups: family and non-family. RESULTS: We analysed 1,451 patients. OHCAs in the family group showed lower rate of good neurological outcomes regardless of witness status: 29.4%, 12.3%, and 38.6% in the first responder, family, and layperson groups in the witnessed and 6.7%, 2.0%, and 7.3% in the unwitnessed cohort. Multivariable logistic regression yielded no significant differences between the three groups: the adjusted odds ratios (AOR) and 95% confidence interval (CI) were 0.57 (0.28-1.15) in the family and 1.18 (0.61-2.29) in the layperson compared to the first responder group. The sensitivity analysis yielded a higher probability of good neurologic recovery in the non-family compared to the family member bystander group in witnessed cohort (AOR, 1.96; 95% CI, 1.17-3.30). CONCLUSION: Paediatric OHCAs had no significant difference between good neurological recovery and the relationship of bystander.

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.

Interaction between bystander sex and patient sex in bystander cardiopulmonary resuscitation for Out-of-Hospital cardiac arrests.

BACKGROUND: Bystander cardiopulmonary resuscitation (CPR) is a critical factor in improving out-of-hospital cardiac arrest (OHCA) survival. The aim of this study was to investigate the interaction effect of bystander sex and patient sex on the provision of bystander CPR. METHODS: This was a retrospective cohort study using national OHCA registry in Korea. The inclusion criteria were adult bystander-witnessed OHCA patients with presumed cardiac etiology from January 2016 to December 2020. The primary outcome was the provision of bystander CPR. Multivariable logistic regression and interaction analysis were conducted to evaluate the impact of bystander sex on bystander CPR provision based on patient sex. RESULTS: The study included 24,919 patients with OHCA, 58.2% with male-bystanders and 41.8% with female-bystanders. Female bystanders were less likely to perform bystander CPR than male bystanders (68.0% vs. 78.8%, adjusted OR (95% CI): 0.62 (0.58-0.66)). Among patients with CPR-trained bystanders, female bystanders had lower odds of bystander CPR (0.85 (0.73-0.97)). In the interaction analysis between bystander and patient sex, a significant difference was observed in the likelihood of bystander CPR according to the patient sex. Female bystanders had lower odds of bystander CPR than male bystanders for male patients (0.47 (0.43-0.50)). However, there were no significant differences between male and female bystanders for female patients (0.91 (0.88-1.07)). CONCLUSION: Female bystanders have a lower likelihood of providing bystander CPR than male bystanders. Additionally, an interaction was observed between bystander sex and patient sex in the providing bystander CPR, with the association being more pronounced in male OHCA patients.

Extracorporeal cardiopulmonary resuscitation for adult out-of-hospital cardiac arrest patients: time-dependent propensity score-sequential matching analysis from a nationwide population-based registry.

BACKGROUND: There is inconclusive evidence regarding the effectiveness of extracorporeal cardiopulmonary resuscitation (ECPR) for out-of-hospital cardiac arrest (OHCA) patients. We aimed to evaluate the association between ECPR and neurologic recovery in OHCA patients using time-dependent propensity score matching analysis. METHODS: Using a nationwide OHCA registry, adult medical OHCA patients who underwent CPR at the emergency department between 2013 and 2020 were included. The primary outcome was a good neurological recovery at discharge. Time-dependent propensity score matching was used to match patients who received ECPR to those at risk for ECPR within the same time interval. Risk ratios (RRs) and 95% confidence intervals (CIs) were estimated, and stratified analysis by the timing of ECPR was also performed. RESULTS: Among 118,391 eligible patients, 484 received ECPR. After 1:4 time-dependent propensity score matching, 458 patients in the ECPR group and 1832 patients in the no ECPR group were included in the matched cohort. In the matched cohort, ECPR was not associated with good neurological recovery (10.3% in ECPR and 6.9% in no ECPR; RR [95% CI] 1.28 [0.85-1.93]). In the stratified analyses according to the timing of matching, ECPR with a pump-on within 45 min after emergency department arrival was associated with favourable neurological outcomes (RR [95% CI] 2.51 [1.33-4.75] in 1-30 min, 1.81 [1.11-2.93] in 31-45 min, 1.07 (0.56-2.04) in 46-60 min, and 0.45 (0.11-1.91) in over 60 min). CONCLUSIONS: ECPR itself was not associated with good neurological recovery, but early ECPR was positively associated with good neurological recovery. Research on how to perform ECPR at an early stage and clinical trials to evaluate the effect of ECPR is warranted.

Bystander cardiopulmonary resuscitation, automated external defibrillator use, and survival after out-of-hospital cardiac arrest.

INTRODUCTION: We aimed to investigate the association between bystander cardiopulmonary resuscitation (CPR) with and without automated external defibrillator (AED) use and neurological outcomes after out-of-hospital cardiac arrest (OHCA) in Korea. METHODS: This cross-sectional study used a nationwide Korean OHCA registry between 2015 and 2019. Patients were categorised into no bystander CPR and bystander CPR with and without AED use groups. The primary outcome was good neurological recovery at discharge. We also analysed the interaction effects of place of arrest, response time, and whether the OHCA was witnessed. RESULTS: In total, 93,623 patients were included. Among them, 35,486 (37.9%) were in the no bystander CPR group, 56,187 (60.0%) were in the bystander CPR without AED use group, and 1950 (2.1%) were in the bystander CPR with AED use group. Good neurological recovery was demonstrated in 1286 (3.6%), 3877 (6.9%), and 208 (10.7%) patients in the no CPR, bystander CPR without AED use, and bystander CPR with AED use groups, respectively. Compared to the no bystander CPR group, the adjusted odds ratio (95% confidence intervals) for good neurological recovery was 1.54 (1.45-1.65) and 1.37 (1.15-1.63) in the bystander CPR without and with AED use groups, respectively. The effect of bystander CPR with AED use was more apparent in OHCAs with witnessed arrest and prolonged response time (≥8 min). CONCLUSION: Bystander CPR was associated with better neurological recovery compared to no bystander CPR; however, the benefits of AED use were not significant. Efforts to disseminate bystander AED availability and ensure proper utilisation are warranted.