OBJECTIVES:To evaluate the cost-effectiveness of implementing an extracorporeal cardiopulmonary resuscitation (ECPR) strategy for refractory out-of-hospital cardiac arrest (OHCA) compared with current practice in Singapore, where it is not routinely used. DESIGN:We performed a simulation-based cost-effectiveness analysis using a decision tree to model acute phase and a Markov model for long-term outcomes over a lifetime horizon, from a healthcare provider perspective. SETTING:Singapore healthcare system. PATIENTS:Nontraumatic adult OHCA patients from Singapore with initial shockable rhythm and no prehospital return of spontaneous circulation were analyzed. INTERVENTIONS:We modeled the implementation of an ECPR strategy and compared it with current practice using only conventional cardiopulmonary resuscitation. Transition probabilities of existing practice were derived from the nationwide Singapore OHCA registry (Pan-Asian Resuscitation Outcomes Study: PAROS), (2010-2016), while ECPR outcomes were based on the Comprehensive Registry of Intensive Care for OHCA Survival in Osaka (Osaka CRITICAL study) (2012-2019). Costs and quality-adjusted life-years (QALYs) were compared between strategies, with scenario analyses conducted to assess the impact of lower age eligibility thresholds and increased transport time to extracorporeal membrane oxygenation-capable hospitals. Incremental cost-effectiveness ratios (ICERs) were estimated using a willingness-to-pay threshold of S$45,000 per QALY. MEASUREMENTS AND MAIN RESULTS:A total of 1462 OHCA cases from Singapore were analyzed; the mean age of patients was 57 years (sd, 11 yr), and 87% were male. In base-case analysis, ICER was estimated at $34,320/QALY, with a positive net monetary benefit of $8,532. Scenario analyses demonstrated that an age-restricted ECPR strategy (< 65 yr) yielded a similar ICER ($33,469/QALY) to the base case. In contrast, incorporating a 10-minute transport extension slightly exceeded the willingness-to-pay threshold ($47,158/QALY). CONCLUSIONS:In this modeling study, adopting an ECPR strategy for OHCA in Singapore was likely to be cost-effective across different age-based eligibility thresholds; however, it was sensitive to delays in transport time. Further implementation research is important to guide scale-up and policy decisions.

OBJECTIVES:To evaluate temporal trends in clinical outcomes among nontraumatic out-of-hospital cardiac arrest (OHCA) patients transported to critical care medical centers (CCMCs) in Japan. DESIGN:Retrospective cohort study. SETTING:Nationwide multicenter registry involving CCMCs in Japan, which are government-designated advanced emergency care institutions specializing in intensive resuscitation and post-cardiac arrest management. Data were obtained from the Japanese Association for Acute Medicine OHCA (JAAM-OHCA) registry from June 1, 2014, to December 31, 2022. PATIENTS:Adult patients (≥ 18 yr old) with nontraumatic OHCA who were transported to CCMCs and had Utstein-style prehospital data available. Patients were categorized into three calendar periods (2014-2016, 2017-2019, and 2020-2022) for temporal comparison. INTERVENTIONS:None. MEASUREMENTS AND MAIN RESULTS:Among 61,725 eligible patients, the proportion with favorable neurologic outcomes decreased from 3.6% (2014-2016) to 3.3% (2017-2019) and further to 2.5% (2020-2022). Using multivariable logistic regression, the adjusted odds ratios (aORs) for favorable neurologic outcome were 1.01 (95% CI, 0.89-1.15) in 2017-2019 and 0.83 (95% CI, 0.72-0.94) in 2020-2022, compared with 2014-2016. Similarly, 30-day survival declined during the same period, from 6.9% to 6.8% and 5.4%. In most predefined subgroups, similar trends were observed. In contrast, neurologic outcomes improved among candidates for extracorporeal cardiopulmonary resuscitation (ECPR), with an aOR of 1.43 (95% CI, 1.06-1.93) in 2020-2022 compared with 2014-2016. CONCLUSIONS:Outcomes among OHCA patients transported to CCMCs remained stable until 2019 but declined during the COVID-19 pandemic period. However, improved outcomes among patients eligible for ECPR suggest that timely and targeted post-arrest interventions may improve outcomes in selected populations.

BACKGROUND:Although current international guidelines strongly recommend uniform early epinephrine administration in out-of-hospital cardiac arrest (OHCA) patients with non-shockable rhythms, how the association between epinephrine and ROSC differs according to the initial rhythm remains unclear. The aim of this study was to investigate whether the association between epinephrine and return of spontaneous circulation (ROSC) differs between patients with asystole and those with pulseless electrical activity (PEA) and how this difference changes over time. METHODS:We analysed adult OHCA patients with non-shockable rhythms registered between June 2014 and December 2021 in the Japanese Association for Acute Medicine's Out-of-Hospital Cardiac Arrest registry. Risk-set matching was performed using time-dependent propensity scores. We evaluated how the time-varying association between epinephrine and ROSC differed according to initial rhythm. RESULTS:Among 58,977 patients, 42,161 had asystole and 16,816 had PEA. The association between epinephrine and ROSC differed by initial rhythm (interaction odds ratio [OR], 0.60; 95% confidence interval [CI], 0.51-0.68) at 5 min after emergency medical service contact, and this difference diminished over time. At the same time point, the OR of epinephrine for ROSC was 1.81 (95% CI, 1.57-2.07) in asystole and 1.43 (95% CI, 1.14-1.58) in PEA in subgroup analyses. A similar trend was observed for 30-day survival, whereas no significant difference was found regarding favourable neurological outcomes at 30 days. CONCLUSIONS:The association between epinephrine and ROSC was greater in patients with asystole than in those with PEA, although a statistically significant association was observed in both groups.

Background The Prehospital Return of Spontaneous Circulation (P-ROSC) score was developed using the Pan-Asian Resuscitation Outcomes Study registry to predict prehospital ROSC. Although external validation studies have been conducted in other Asian countries, their results have been inconsistent. This study aimed to externally validate the P-ROSC score using a nationwide Japanese registry and assess its performance across geographic regions. Methods We analysed out-of-hospital cardiac arrest (OHCA) cases of medical origin registered in the All-Japan Utstein Registry between 2015 and 2020. The primary outcome was prehospital ROSC, defined as ROSC at the scene or during transport. Model discrimination was evaluated using the area under the receiver operating characteristic curve (AUC), and calibration was assessed using calibration plots. Subgroup analyses were conducted across eight regions of Japan. Results A total of 493,695 OHCA cases were included, with a median age of 81 years, and 56.5% were men. Overall, 46,760 patients (9.5%) achieved prehospital ROSC. The AUC of the P-ROSC score based on the predefined model was 0.794 (95% confidence interval [CI]: 0.792–0.796). The calibration plot showed moderate agreement between predicted and observed outcomes. The region-specific AUCs varied across Japan, with the highest AUC in Tohoku (0.822, 95% CI: 0.816–0.828) and the lowest in Hokkaido (0.772, 95% CI: 0.764–0.780). Conclusions The P-ROSC score demonstrated fair discrimination and moderate calibration for predicting prehospital ROSC in Japanese patients with OHCA. Its application should consider regional variations in patient characteristics and emergency medical service structures that may influence transportation and generalisability.

Background: The associations between symptom characteristics and patients' interpretations and sources of knowledge about acute coronary syndrome (ACS) remains unclear. Methods and Results: We enrolled 81 patients with ACS. Patients who misinterpreted their symptoms more frequently reported atypical features such as tenderness (13.3% vs 0%; P=0.028) and syncope (11.8% vs 0%; P=0.011). Common knowledge sources among patients who correctly interpreted their symptoms included television, healthcare professionals, and the internet without social media. Conclusions: Patients experiencing atypical symptoms often misinterpret them. Most knowledge sources for those who interpreted correctly were traditional.

Background:The current landscape of emergency care (EC) is marked by high demand, leading to issues such as emergency department boarding, overcrowding, and subsequent delays that impact the quality and safety of patient care. Integrating data science into EC can enhance decision-making with predictive, preventative, personalized, and participatory approaches. However, gaps in adherence to fairness, accountability, interpretability, and responsibility are evident, particularly due to barriers to data-sharing, which often result in a lack of transparency and robust oversight in these applications. Objective:The FAIR-EC (Fair, Accountable, Interpretable, and Responsible-Emergency Care) collaboration adapts the existing Fair, Accountable, Interpretable, and Responsible principles to address emerging challenges as data science integrates with EC. This initiative aims to transform EC by establishing ethical artificial intelligence standards specifically tailored for this integration. By bridging the gap between EC professionals, data scientists, and other stakeholders, the collaboration promotes international cooperation that leverages advanced data science techniques to enhance EC outcomes across different care settings. Methods:We propose a federated research design to analyze extensive datasets from various global institutions without compromising patient privacy. This approach transforms epidemiological research with advanced data science techniques, emphasizing the harmonization of data for comprehensive analyses across different health care systems. Results:The FAIR-EC initiative has facilitated the identification and harmonization of datasets from diverse geographical regions, enabling the examination of regional variations in EC practices. As of paper submission, participating sites have identified retrospective EC datasets totaling >2 million records (eg, Duke Health >400,000 and Singapore General Hospital >1.7 million records). Initial projects have demonstrated feasibility and operational readiness, including implementation of federated workflows and ongoing development of a federated scoring system, cross-site evaluation, and adaptation of association studies and predictive models across various regions. Cross-site harmonization and pilot analyses are underway (with local ethics approvals in progress), and first multisite results are expected to be submitted in mid-late 2026, with additional project-level publications anticipated in 2027. These efforts highlight the feasibility of leveraging advanced data science techniques to address the complexities of EC while preserving patient privacy without centralizing individual-level data. This project was funded from September 1, 2022, to August 31, 2023. Conclusions:FAIR-EC integrates data science ethically and effectively into EC, addressing challenges such as fragmented data, real-time handoffs, and public health crises. Its federated design harmonizes diverse data streams while preserving privacy, and its emphasis on ethical artificial intelligence aligns with the dynamic nature of EC. Despite challenges in data variability and system complexity, FAIR-EC establishes a strong foundation for innovation in global EC.

OBJECTIVE:Metoclopramide is widely used to treat nausea, vomiting, and headache. However, it may cause extrapyramidal symptoms (EPS) such as akathisia. Continuous intravenous (IV) infusion has been proposed as a safer alternative to bolus injection. This study aimed to compare the risk of EPS and effectiveness between continuous and bolus IV metoclopramide administration. METHODS:We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) comparing continuous vs. bolus IV administration of metoclopramide. Databases searched included CENTRAL, MEDLINE, Embase, CINAHL, ClinicalTrials.gov, and ICTRP (inception to January 2025). The primary analysis was restricted to trials conducted in the emergency department (ED), with secondary analyses including all clinical settings. Primary outcome was the occurrence of EPS. Secondary outcomes included nausea severity; headache severity; occurrence of akathisia. Pooled estimates were calculated using random-effects models (standardized mean differences [SMDs], risk ratios [RRs]). RESULTS:Among 5878 randomized controlled trials screened, seven trials (924 patients) were included in the meta-analysis. Across five ED trials, continuous infusion was associated with a lower risk of EPS (RR: 0.34; 95% CI: 0.15 to 0.79; I2 = 75.1%), with EPS outcomes in ED trials being defined as akathisia. Two trials assessed nausea severity (SMD: 0.10; 95% CI: -0.13 to 0.32; I2 = 0%). One trial assessed headache severity (SMD 0.17; 95% CI: -0.18 to 0.53). CONCLUSION:In the emergency department, continuous intravenous metoclopramide was associated with a lower risk of EPS without clear differences in symptom control, suggesting that continuous infusion may be a reasonable approach in clinical practice.

Background: Insomnia symptoms associated with late chronotypes are prevalent among young adults, and frequently lead to sleep deprivation, morning-awakening difficulties, and excessive daytime sleepiness. These conditions are associated with psychological distress, impaired academic functioning, and reduced self-esteem. Although chronobiological behavioral interventions are effective, their accessibility remains limited. To bridge this gap, we developed a smartphone application delivering digital brief behavioral treatment for insomnia (BBT-I). We also designed a four-week program integrating the app with light therapy (LT) via wearable glasses named "Digital BBT-I + LT". This randomized controlled trial will evaluate the efficacy of digital BBT-I with LT and digital BBT-I alone compared with a waitlist control group. Methods: This three-arm parallel-group randomized controlled trial will target young adults with insomnia symptoms and late chronotypes. Participants will be randomized to receive digital BBT-I with adjunctive LT, digital BBT-I alone, or a waitlist control condition. The primary outcome will be insomnia symptom severity, assessed using the Insomnia Severity Index. Evaluations will be conducted at baseline, weekly during the four-week intervention period (days 8, 15, 22, and 29), and at the 3-month follow-up. Discussion: Late chronotypes and insomnia significantly impair sleep and mental health in young adults. Despite the recognized importance of chronobiology-based treatments, they are rarely adopted as standard care. This highlights the need for scalable digital interventions, such as digital BBT-I. By rigorously assessing these strategies, this trial aims to provide clinical evidence regarding accessible interventions to improve sleep and mental health outcomes in this population.

ABSTRACTBackground: Despite the growing evidence for intermittent fasting (IF) as a weight management strategy, most trials compare IF against passive controls, precluding isolation of IF-specific effects, and few have evaluated pragmatic, fully web-based programs that could be disseminated at scale.Objective: To evaluate the effectiveness of a Brief Online Intermittent Fasting Program (BOIF) combining once-weekly replacement meal fasting, home-based exercise, and app-based messaging on weight loss versus an active control over 12 weeks in adults with overweight and obesity in Japan.Methods: Two-arm, parallel-group randomized controlled trial enrolling 82 adults with BMI ≥23 kg/m², aged 20 to <65 years, at Kyoto University and The University of Tokyo, Japan. Participants are randomized 1:1 to BOIF (Component A: once-weekly ~400 kcal replacement meal fasting with online support from a registered dietitian; Component B: weekly app-based messaging; Component C: three-times-weekly home-based exercise) or active control (Components B and C only). The primary outcome is the proportion of participants achieving ≥3% body weight reduction at 12 weeks, analyzed using Fisher’s exact test under the intention-to-treat principle. Secondary outcomes include changes in body weight, fat mass, muscle mass, physical activity, and dietary intake.Conclusion: This trial provides evidence on a pragmatic, low-cost IF program scalable via digital platforms. Findings may inform population-level approaches to obesity prevention.​Trial Registration: UMIN-CTR UMIN000058429; https://tinyurl.com/3wj6ebyw

Predicting postpartum hemorrhage risk can be useful in clinical settings. We aimed to develop and validate a clinical prediction model for postpartum hemorrhage in patients who undergo elective cesarean section. This retrospective observational study included patients who underwent elective cesarean section between January 2008 and September 2021. The primary outcome to be predicted was postpartum hemorrhage, defined as blood loss of ≥ 1500 mL during surgery. We used data prior to January 2018 for the development cohort and after for the validation cohort. We then constructed a multivariate logistic regression model. The model performance, including discrimination and calibration, was evaluated and its diagnostic ability was assessed. Of the 4070 patients, 860 (21.0

BackgroundIntermittent fasting emerges as a promising dietary approach against obesity, offering a cost-effective strategy for implementation via web-based platforms. We developed a Brief Online Intermittent Fasting Program (OIF), featuring a self-administered, weekly 1-day fasting regimen with replacement meals delivery, online guidance, and app messaging to support adherence. ObjectiveThis pilot study aimed to assess the preliminary effectiveness, feasibility, and safety of the OIF on weight loss in adults with overweight and obesity in Japan. Secondary objectives were to assess its effects on body composition and metabolic markers. MethodsThis 12-week, 1:1 randomized controlled trial recruited adults with overweight and obesity (BMI from 23 to <35) in 1 university, 1 hospital, and 2 company offices. Participants were randomized into 2 groups stratified by sex and age (<40 or ≥40 years). The intervention group received very low-calorie (407 kcal) meal replacements for weekly intermittent fasting, online guidance via Zoom (Zoom Video Communications, Inc), and app messages encouraging fasting and healthy lifestyles. The control group received app messages promoting healthy lifestyles only. Interventions were administered by a nonblinded researcher. The primary outcome was the change in body weight after 12 weeks, analyzed using intention-to-treat principles and adjusted for sex, age, and baseline weight. Secondary outcomes encompassed body composition, blood pressure, biomarkers (eg, hemoglobin A1c, triglycerides, and cholesterol), quality of life, physical activity, intervention adherence, and adverse events. ResultsA total of 57 individuals were enrolled (28 in the intervention group and 29 in the control group). At 12 weeks, 25 participants in the intervention group and 27 participants in the control group completed follow-up. The baseline median weight was 75.8 (IQR 68.3-80.6) kg for the intervention group and 74.8 (IQR 69.8-81.8) kg for the control group. The mean weight change was –0.9 (SD 1.9) kg in the intervention group and +0.6 (SD 1.4) kg in the control group. The adjusted between-group difference in weight change was statistically significant at –1.6 (95% CI –2.5 to –0.8) kg. Fat mass change was not statistically significant (–0.1, 95% CI –1.3 to 1.4 kg), but muscle mass reduction was implied (–1.3, 95% CI –2.5 to –0.2 kg). Intervention adherence was 79% (22/28) in the intervention group. No serious adverse events were reported, and there were no significant changes in key biomarkers, such as hemoglobin A1c or quality of life. ConclusionsThe OIF demonstrated effectiveness in promoting modest weight loss among adults with overweight and obesity over 12 weeks, with high feasibility and safety indicated by low dropout rates and absence of serious adverse events. However, the observed reduction in muscle mass indicates a need for program refinement, such as incorporating exercise guidance, to optimize health outcomes. Trial RegistrationUMIN-CTR UMIN000050437; https://tinyurl.com/4x5h2t2x

BACKGROUND: Weaning from cardiopulmonary bypass (CPB) is a critical step in cardiovascular surgery. Although ionized calcium (iCa) plays a crucial role in myocardial contractility, and hypocalcemia commonly occurs during CPB, only a few studies have examined the association between iCa levels and clinical outcomes following CPB. This study aimed to evaluate whether iCa levels during CPB weaning were associated with clinical outcomes. METHODS: This multicenter retrospective study was conducted in three Japanese hospitals. Adult patients (aged ≥ 18 years) who underwent cardiovascular surgery with CPB were included. Exposure was defined as iCa concentration during CPB weaning. The primary outcome was low cardiac output syndrome (LCOS) on ICU admission, which was determined when at least one of the following three criteria was met: (i) postoperative MCS use, (ii) cardiac index <2.0 L min -1 m -2 , (iii) use of two or more inotropes (dopamine, dobutamine, adrenaline, and milrinone) at 1 hour following the end of the surgery. The patients were divided into four groups based on iCa quartile: low iCa group (iCa ≤ 1.05 mmol L -1 ), standard iCa group (1.05 < iCa ≤ 1.13 mmol L -1 ), moderate-high iCa group (1.13 < iCa ≤1.24 mmol L -1 ), and high iCa group (iCa > 1.24 mmol L -1 ). Multivariate logistic regression analyses were performed to calculate adjusted odds ratios (ORs) with 95% confidence intervals (CIs). RESULTS: In total, 2,382 patients were included between September 2012 and December 2022. The median age was 70 years (IQR: 60–76 years), and 1,464 patients (61%) were men. The overall LCOS incidence was 501 cases (21%). Compared to the standard iCa group, the adjusted ORs for LCOS were 1.45 (95% CI, 1.06 to 1.99, P = .020) in the low iCa group, 1.42 (95% CI, 1.01 to 2.00, P = .046) in the moderate-high iCa group, and 1.36 (95% CI, 0.95 to 1.94, P = .094) in the high iCa group. CONCLUSIONS: Both low and high iCa levels at CPB weaning were associated with an increased risk of postoperative LCOS in patients undergoing cardiovascular surgery.

Background: In Japan, approximately 90,000 individuals die annually from sudden cardiac death (SCD). Predicting SCD using electronic health records (EHRs) from hospitals remains difficult. The growing use of wearable devices enables the continuous collection of personal health records (PHRs) and offers an opportunity to develop robust databases by integrating PHRs with EHRs. Applying artificial intelligence (AI) to these combined datasets may enable the early detection of SCD precursors. Objective: To develop an AI-based predictive model for SCD and related cardiovascular events by integrating PHRs with EHRs. Methods: We are prospectively enrolling high-risk patients—those with prior heart failure (HF), acute coronary syndrome (ACS), or out-of-hospital cardiac arrest—from seven Japanese centers. Participants use wearable devices (e.g., Fitbit, Apple Watch, or VINSTA ring) and home monitors to collect body weight and blood pressure. These data is integrated with EHRs, including clinical outcomes, laboratory tests, electrocardiograms, and echocardiograms. The primary endpoint is SCD, and the secondary endpoints include ACS, lethal arrhythmias, and hospitalization for HF. AI-based analysis was utilized to identify physiological changes preceding cardiovascular events. Results: From April 2024 to October 2025, 212 patients (mean age 58 ± 13 years; 77% male) were enrolled, yielding 167 person-years of follow-up. There were 12 cardiovascular events (3 HF, 3 ACS, 6 lethal arrhythmias) and no SCD. Temporary analysis revealed: 1. In HF, pulse rate increased from baseline 14 days prior, followed by weight gain seven days prior, and increased subjective symptoms three days before hospitalization. (Fig. 1) 2. In ACS, ST-segment depression detected by VINSTA ring appeared two days before the onset and resolved after treatment. (Fig. 2) 3. Event-positive participants showed higher mean pulse rate (81 ± 11 bpm vs. 70 ± 11 bpm; n = 4 vs. 66), greater orthostatic systolic drop (-2.3 ± 14.1 mmHg vs. -0.5 ± 7.2 mmHg; n = 2 vs. 19), and more frequent reports of subjective symptoms (1.9 ± 1.4 items vs. 0.7 ± 1.4 items; n = 4 vs. 57) seven days prior to the events. (Fig.3) Discussion: Integrating PHRs with EHRs enables continuous, personalized monitoring and early detection of cardiovascular deterioration. AI-driven analysis of these multimodal data may substantially enhance SCD risk prediction and support timely interventions to prevent adverse events.

Aim: We aimed to assess the association between base excess (BE) levels and neurological outcomes in patients with out-of-hospital cardiac arrest (OHCA), accounting for the time from cardiac arrest onset to blood sampling. Methods: This multicentre study was conducted in Osaka, Japan, and enrolled consecutive patients with OHCA who were transported to 16 medical centres between 2012 and 2021. Patients aged ≥ 18 years with witnessed OHCA and available BE measurements upon hospital arrival were examined. Patients were stratified into Q1 (BE ≤ −21.1 mmol/L), Q2 (−21.1 < BE ≤ −15.7 mmol/L), Q3 (−15.7 < BE ≤ −10.4 mmol/L) and Q4 (BE > −10.4 mmol/L) groups based on BE levels. The primary outcome was 1-month survival with a favourable neurological outcome (Cerebral Performance Category scale score: 1 or 2). Results: Among the 23,854 patients with OHCA, only 6066 were included in the final analysis. Approximately 3.2 %, 4.7 %, 9.9 % and 23.7 % of patients in the Q1, Q2, Q3 and Q4 groups, respectively, achieved favourable neurological outcomes at 1 month. Compared with Q4, the adjusted odds ratio for a favourable neurological outcome in Q1 was 0.13. Subgroup analysis revealed a significant interaction between prehospital return of spontaneous circulation (ROSC) and neurological outcomes; neurological outcomes worsened as BE decreased in patients with ROSC but not in those without ROSC. Conclusion: Lower BE levels upon hospital arrival are associated with poorer neurological outcomes and may serve as prognostic indicators in patients with OHCA who achieved prehospital ROSC.

BACKGROUND:Acute coronary syndrome (ACS) requires prompt diagnosis and treatment. Although "OPQRST" (Onset, Provocation, Quality, Region/Radiation, Symptoms, and Time) is commonly used, the evidence linking emergency department (ED) chest pain characteristics to ACS remains inconclusive. This study evaluated detailed symptoms in ED patients with and without ACS using a broad chest pain registry with symptom data. METHODS AND RESULTS:This single-center prospective study was conducted at Rakuwakai-Otowa Hospital in Kyoto, Japan, as a pilot study for a multicenter registry. We enrolled 420 consecutive adult patients presenting with chest pain at the ED from June 2022 to May 2023. Baseline characteristics (including symptoms) and outcomes were recorded. Of the 420 patients, 65 (15.5%) were diagnosed with ACS. Patients with and without ACS differed in the proportion with sudden onset (58.5% vs. 27.6%, respectively), radiation to the tooth (9.2% vs. 0.6%, respectively), and cold sweat (diaphoresis; 44.6% vs. 16.9%, respectively). In the overall population, positive likelihood ratios were 2.12 (95% confidence interval [CI] 1.63-2.76) for sudden onset, 16.38 (95% CI 3.38-79.41) for radiation to the tooth, and 2.64 (95% CI 1.85-3.77) for diaphoresis. CONCLUSIONS:This study in a suburban area of Japan (one of the most super-aged societies) identified key chest pain characteristics in a broad chest pain cohort (i.e., sudden onset, radiation to the tooth, and diaphoresis) that may help with the rapid triage and diagnosis of ACS.

Background The causes underlying out‐of‐hospital cardiac arrest (OHCA) are rarely investigated. This study aimed to investigate causes of OHCA in CRITICAL (Comprehensive Registry of In‐Hospital Intensive Care for OHCA Survival), a multicenter OHCA registry in Osaka, Japan. Methods Nontraumatic patients with OHCA (by CARES [Cardiac Arrest Registry to Enhance Survival] criteria) aged 18 to 90 years between July 1, 2012 and December 31, 2020 were included. By Japanese law, all patients with OHCA (resuscitated or not) must be transported to the emergency department where death is declared if resuscitation is unsuccessful; this latter group was considered presumed sudden cardiac deaths whereas those surviving to hospitalization were considered resuscitated OHCA. We compared underlying causes of OHCA in presumed sudden cardiac deaths, survivors of OHCA (alive 30 days after the event), and nonsurvivors of OHCA (died during hospitalization). Causes were confirmed when autopsy or postresuscitation hospital workup was performed and probable when determined by attending physician impression (partial workup). Results Of 12 252 total OHCAs, 8005 (65.3%) were. presumed sudden cardiac deaths, 4247 (34.7%) were resuscitated, and 1293 (10.6%) were survivors. Resuscitated OHCA cardiac causes comprised 73.2% (n=3110) and noncardiac causes 26.8% (n=1137). Cardiac cause, most commonly acute coronary syndrome, was more prevalent in survivors of OHCA than nonsurvivors (85.7% [n=1137] versus 67.8% [n=2002]; P<0.001). Although 40.4% of the survived at 30 days cases were acute coronary syndrome, cerebrovascular disease accounted for 9.8% of nonsurvivors of OHCA and nearly one fifth (n=144, 17.8%) of middle‐aged cases. Conclusions Cardiac cause was more common in survivors than cases dying in the emergency room (sudden deaths) or in hospital after initial resuscitation (nonsurvivors of OHCA). Causes in nonsurvivors of OHCA who died in hospital were more heterogeneous than those of survivors of OHCA, especially cerebrovascular emergencies.

Extracorporeal cardiopulmonary resuscitation (ECPR) requires advanced skills for induction and management. This study evaluated whether the outcomes of ECPR differ by institutional volume. Using the Japanese Association for Acute Medicine–Out-of-Hospital Cardiac Arrest (JAAM-OHCA) registry, we analyzed adult patients (aged ≥18 years) who received ECPR between 2014 and 2020, focusing on 30 day in-hospital survival and favorable neurologic prognosis at 30 days defined as Cerebral Performance Category (CPC) 1–2. Facilities were categorized into tertiles by annual ECPR volume. Multivariable logistic regression examined outcomes across low (≤4.7 cases/year), medium (4.8–7.8 cases/year), and high (≥7.9 cases/year) volume groups. A total of 1,759 patients from 83 centers were included, with an overall 30 day survival of 21.1% and CPC 1–2 rate of 10.1%. We observed no statistically significant differences in the respective rates of 30 day survival and neurologic outcomes in the medium ECPR volume group (adjusted odds ratios 1.09 [95% confidence interval {CI}, 0.82–1.47] and 0.85 [0.56–1.26]) and higher ECPR volume group (adjusted odds ratios 1.27 [95% CI, 0.95–1.70] and 1.11 [0.75–1.63]) compared with the lower ECPR volume group. These findings suggest that ECPR outcomes for out-of-hospital cardiac arrest are not significantly affected by institutional ECPR volume.

INTRODUCTION:Temperature control is a fundamental intervention for neuroprotection following resuscitation from cardiac arrest. However, evidence regarding the efficacy of hypothermia in post-cardiac arrest syndrome (PCAS) remains unclear. Retrospective studies suggest that the clinical effectiveness of hypothermia may depend on the severity of PCAS. The R-CAST OHCA trial aims to compare the efficacy of hypothermia versus normothermia in improving 30-day neurological outcomes in patients with moderately severe PCAS following out-of-hospital cardiac arrest. METHODS AND ANALYSIS:The multicentre, single-blind, parallel-group, superiority, randomised controlled trial (RCT) is conducted with the participation of 35 emergency and critical care centres and/or intensive care units at academic and non-academic hospitals. The study enrols moderately severe PCAS patients, defined as those with a revised post-Cardiac Arrest Syndrome for induced Therapeutic Hypothermia score of 5.5-15.5. A target number of 380 participants will be enrolled. Participants are randomised to undergo either hypothermia or normothermia within 3 hours after return of spontaneous circulation. Patients in the hypothermia group are cooled and maintained at 34°C until 28 hours post-randomisation, followed by rewarming to 37°C at a rate of 0.25°C/hour. Patients in the normothermia group are maintained at normothermia (36.5°C-37.7°C). Total periods of intervention, including the cooling, maintenance and rewarming phases, will occur 40 hours after randomisation. Other treatments for PCAS can be determined by the treating physicians. The primary outcome is a favourable neurological outcome, defined as Cerebral Performance Category 1 or 2 at 30 days after randomisation and compared using an intention-to-treat analysis. ETHICS AND DISSEMINATION:This study has been approved by the Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital, Ethics Committee (approval number: R2201-001). Written informed consent is obtained from all participants or their authorised surrogates. Results will be disseminated via publications and presentations. TRIAL REGISTRATION NUMBER:jRCT1062220035.