Cardiac Arrest Registry Research Articles

Performance of the medical priority dispatch system in correctly classifying out-of-hospital cardiac arrests as appropriate for resuscitation

BackgroundEmergency dispatch centres receive emergency calls and assign resources. Out-of-hospital cardiac arrests (OHCA) can be classified as appropriate (requiring emergent response) or inappropriate (requiring non-emergent response) for resuscitation. We sought to determine system accuracy in emergency medical services (EMS) OHCA response allocation. MethodsWe analyzed EMS-assessed non-traumatic OHCA records from the British Columbia (BC) Cardiac Arrest registry (January 1, 2019-June 1, 2021), excluding EMS-witnessed cases. In BC the “Medical Priority Dispatch System” is used. We classified EMS dispatch as “emergent” or “non-emergent” and compared to the gold standard of whether EMS personnel decided treatment was appropriate upon scene arrival. We calculated sensitivity, specificity, and positive and negative predictive values (PPV, NPV), with 95% CI’s. ResultsOf 15,371 non-traumatic OHCAs, the median age was 65 (inter quartile range 51–78), and 4834 (31%) were women; 7152 (47%) were EMS-treated, of whom 651 (9.1%) survived). Among EMS-treated cases 6923/7152 had an emergent response (sensitivity = 97%, 95% CI 96–97) and among EMS-untreated cases 3951/8219 had a non-emergent response (specificity = 48%, 95% CI, 47 to 49). Among cases with emergent dispatch, 6923/11191 were EMS-treated (PPV = 62%, 95% CI 61–62), and among those with non-emergent dispatch, 3951/4180 were EMS-untreated (NPV = 95%, 95% CI 94–95); 229/4180 (5.5%) with a non-emergent dispatch were treated by EMS. ConclusionThe dispatch system in BC has a high sensitivity and moderate specificity in sending the appropriate responses for OHCAs deemed appropriate for treatment by paramedics. Future research may address strategies to increase system specificity, and decrease the incidence of non-emergent dispatch to EMS-treated cases.

Abstract 281: External Validation Of The Tips65 Score For Predicting Good Neurological Outcome In Out-of-hospital Cardiac Arrest Patients Treated With Extracorporeal Cardiopulmonary Resuscitation

Introduction: Estimating prognosis after out-of-hospital cardiac arrest (OHCA) at early timing during resuscitation efforts is important to select appropriate candidates for extracorporeal cardiopulmonary resuscitation (ECPR). The TiPS65 scoring system is a prediction model that can be used for predicting favorable neurological outcome of adult OHCA patients treated with ECPR using the following four variables: time from call to hospital arrival, initial cardiac rhythm on hospital arrival, initial pH value, and age. However, it is not yet externally validated. We aimed to perform the external validation of the TiPS65 score. Methods: This prognostic study used data from the Japanese Association for Acute Medicine Out-of-Hospital Cardiac Arrest registry, a nationwide, multicenter, prospectively registered database including 83 emergency departments in Japan from January 2018 to December 2019. All adult OHCA patients with shockable rhythm who were treated with ECPR were included. The primary outcome was 30-day survival with favorable neurological outcome defined as Cerebral Performance Category 1 or 2. The predicted probability of outcomes in this cohort was calculated according to the formula developed in the original study. The discrimination and calibration performances were investigated with c-statistic and calibration plots, respectively. Results: A total of 590 patients (men: 517 [81.6%], median age [interquartile range]: 60 [50-69] years) were included, and favorable neurological outcome were reported in 64 (10.8%). The c-statistic of the prediction model was 0.752 (95% CI: 0.694-0.81). The mean predicted probabilities were 1.6% (range: 1.6%-1.6%), 4.5% (3.1%-5.9%), 12% (10.1%-13.9%), 26.2% (22.7%-29.7%), and 48.8% (48.8%-48.8%) for a TiPS65 score of 0, 1, 2, 3, and 4, respectively. These scores were generally well-calibrated to the observed outcomes. Conclusions: In our external validation study of the TiPS65 score for OHCA patients treated with ECPR, the score showed good discrimination and calibration performances. This score would be helpful in the decision-making process for patient selection for ECPR after OHCA.

Abstract 11: Community Interventions To Improve Out-of-hospital Cardiac Arrest Survival: Targeting Public Housing Could Be A Solution

Background: Identifying well-suited areas for community-targeted interventions to improve bystander interventions and OHCA survival, particularly in deprived communities, has been warranted by the AHA. Public housing projects are publicly subsidized, geographically well-defined, have local leadership, and residents typically have a high prevalence of OHCA predictors. To assess the potential reach of community interventions in public housing, we investigated the incidence of OHCA in public housing projects in Vienna (Austria) and Copenhagen (Denmark) and compared it with remaining residential areas. Methods: Non-EMS witnessed OHCAs occurring in residential areas in Vienna (2017-2021) and Copenhagen (2016-2020) were included from the Viennese and Danish Cardiac Arrest Registry, respectively. Population density and residential areas were obtained from Urban Atlas; public housing data from City of Vienna, and the Danish National Building Foundation. We compared OHCA/km 2 and OHCA/100,000 inhabitants between public housing projects and other residential areas using Poisson regression of rates. We calculated the proportion of OHCAs occurring within 100 meters of public housing projects. Results: In Vienna vs. Copenhagen, 32% (1,391/4,313) vs. 35% (817/2,335) of residential OHCAs occur in public housing areas. The relative ratio of OHCA/km 2 and OHCA/100,000 inhabitants is 3-fold and 1.5-fold higher in public housing than in other housing areas, respectively (Figure 1). Including the immediate surroundings, public housing covered 64.8% vs. 56.1% of all residential OHCAs in Vienna and Copenhagen. Conclusion: Public housing projects in Vienna and Copenhagen had a substantially higher incidence of OHCA than other residential areas covering 1/3 of all OHCAs in residential areas and ~60% when including nearby neighborhoods. Community initiatives targeting these areas may be an efficient strategy to improve bystander interventions and survival.

Abstract 242: Association Of The Nearest Static AED With Treatment And Outcome Of OHCA In Forsyth County, North Carolina

Introduction: Over the last two decades, publicly accessible AEDs have become available in communities across the US, allowing bystanders to rapidly intervene during OHCA. The impact of static AEDs on rates of bystander AED application and OHCA outcomes is poorly understood. Methods: We created a static AED registry for Forsyth County, NC (mixed rural-urban county with population ~ 380,000 ) primarily through phone-based surveys of businesses. These data were linked to the Cardiac Arrest Registry to Enhance Survival and geocoded to calculate proximity between OHCA and nearest static AED. The AHA recommends that publicly accessible AEDs be placed to achieve bystander retrieval within 100 meters (m) of OHCA. Multivariable logistic regression modeling examined the relationship between AED proximity and survival to hospital discharge. Results: Included were 2078 patients >18 years old with OHCA between 2013-2019 and 573 businesses with at least one AED. There were 219 (10.5%), 190 (9.1%), 1669 (80.3%) OHCAs with an AED within <100m, 100-200m, and >200m, respectively. OHCA incidence was highest where static AEDs were closest. Static AEDs within 100m of OHCA were primarily at residential facilities (41.1%), health care clinics (26.5%), churches (9.1%), and schools (6.8%). Among OHCAs with nearest AED >200m, AEDs were primarily owned by schools (32.2%), healthcare facilities (15%), industrial facilities (10.6%), and churches (10.4%). Bystander CPR was highest for OHCAs in closest proximity to an AED (<100m: 61.2%; 100-200m: 51.6%; >200m: 39.5%, p<0.001). Bystander AED application was highest where static AEDs were closest to OHCA (28.3%, 14.2%, and 3.8% at <100m, 100-200m, and >200m, respectively, p<0.001). Among patients who were defibrillated, bystander defibrillation was 18.1%, 20%, and 3.9% (p<0.001). There was no difference for survival to hospital discharge (<100m: 15.1%; 100-200m: 15.3%; >200m: 13.1%, p=0.54), even after adjustment (aOR 1.002, 95% CI 0.995-1.008 per 10m decrease). Conclusion: Only 10% of OHCAs in Forsyth County were within 100 meters of a static AED. Bystander CPR and AED application were highest where static AEDs were <100m from OHCA. Despite this, there was no association between AED proximity and survival to hospital discharge.

Abstract 119: Resuscitation Outcomes In Covid-19-associated Out-of-hospital Cardiac Arrest

BACKGROUND: Since the beginning of the pandemic, there have been numerous reports of increased mortality in the setting of both in-hospital (IHCA) and out-of-hospital cardiac arrest (OHCA) in patients with novel coronavirus-19 (COVID-19) infection. Due to these alarming mortality rates, it has been proposed that resuscitation may represent futility when COVID-19 is suspected or confirmed in patients with cardiac arrest. However, it continues to remain unclear whether the currently available data is sufficient to be broadly applied to all patients and hospitals. HYPOTHESIS: In COVID-positive patients presenting after OHCA, resuscitation should be pursued and is not futile as has previously been suggested. METHODS: 264 consecutive patients presenting to the University of Minnesota Medical Center were obtained from the Cardiac Arrest Registry to Enhance Survival (CARES) database from March 2020 through April 2022. Patient data was obtained retrospectively for COVID19 infection status, initial documented arrest rhythm, and survival to hospital discharge. RESULTS: 264 patients were collected for analysis with 2 being excluded due to incomplete data. Of the remaining 262, 16 were found to be COVID-positive. Of these patients, 2 (12.5%) survived to hospital discharge compared to 72 (29.2%) in the group without COVID. In COVID-positive patients presenting with initially shockable rhythm (11 patients), survival was 18.2% compared with no survival noted in those with initially non-shockable rhythm. 9 patients with COVID were cannulated for ECMO, with 1 (11.1%) surviving to hospital discharge. CONCLUSIONS: This study provides insight into resuscitation in the setting of OHCA when COVID is suspected or confirmed. Though small in overall number of patients, our study indicates that resuscitation efforts in COVID-positive patients are not futile, as has previously been suggested.

Abstract 270: Eligibility Of Out-of-hospital Cardiac Arrest Patients For Extracorporeal Cardiopulmonary Resuscitation In The United States: A Geographic Information System Model

Introduction: Recent evidence suggest that ECPR may improve survival rates for nontraumatic out-of-hospital cardiac arrest (OHCA). Eligibility criteria for ECPR are often based on patient age, clinical variables, and facility capabilities. Expanding access to ECPR across the U.S. requires a better understanding of how these factors interact with transport time to ECPR centers. Methods: We constructed a Geographic Information System (GIS) model to estimate the number of ECPR candidates in the U.S. We utilized a Resuscitation Outcome Consortium (ROC) database to model time-dependent rates of ECPR eligibility and the Cardiac Arrest Registry to Enhance Survival (CARES) registry to determine the total number of OHCA patients who meet pre-specified ECPR criteria within designated transportation times. Potential ECPR centers were categorized as Extracorporeal Membrane Oxygenation (ECMO)-ready, ECMO-capable, or percutaneous coronary intervention (PCI)-capable centers using data from the Extracorporeal Life Support Organization and the American Hospital Directory. The combined model was used to estimate the total ECPR candidates and the effects of patient and hospital factors on ECPR eligibility. Results: There were 588,203 OHCA patients in the CARES registry from 2013 to 2020. After applying clinical eligibility criteria, 22,104 (3.76%) OHCA patients were eligible for ECPR. The rate of ROSC increased with longer resuscitation time, which resulted in fewer ECPR candidates. The proportion of OHCA patients eligible for ECPR increased with older age cutoffs. Only 1.68% (9,889/588,203) of OHCA patients in the U.S. were eligible for ECPR based on a 45-minute transportation time to an ECMO-ready center model, representing the current state of ECPR in the U.S. The proportion of OHCA patients eligible for ECPR ranged from 0.68% (4,027 patients in the 15-minute transportation time to ECMO-ready center model) to 2.81% (16,558 patients in the 45-minute transportation time to PCI-capable center model). Conclusions: Less than 2% of OHCA patients are eligible for ECPR in the U.S. GIS models can identify the impact of clinical criteria, transportation time, and hospital capabilities on ECPR eligibility to inform future implementation strategies.

Abstract 12: Identifying Emergency Medical Service Agencies In Black And Hispanic Communities With High Cardiac Arrest Survival Rates

Background: Black and Hispanic individuals have lower survival rates for out-of-hospital cardiac arrest (OHCA). Whether there are Emergency Medical Service (EMS) agencies in Black and Hispanic communities with high survival rates for OHCA is unknown but critical to identifying strategies to reduce racial and ethnic disparities in OHCA survival. Methods: Within the Cardiac Arrest Registry to Enhance Survival, we identified adults with non-traumatic OHCA during 2015-2019. EMS agencies were categorized as working in Black/Hispanic communities if >50% of residents in their catchment area were Black or Hispanic. Using hierarchical logistic regression, we calculated risk-standardized survival rates (RSSR) to hospital admission for OHCA in each EMS agency, adjusted for patients’ age, sex, witnessed arrest status, presumed arrest etiology, initial cardiac arrest rhythm, and arrest location. We then examined the distribution of EMS agencies that work in Black/Hispanic communities across quartiles of OHCA survival. Results: Among 764 EMS agencies (258,342 OHCAs), the median RSSR was 27.4% with an absolute difference of >10% across quartiles (median 22.4% in the lowest vs. 32.9% in the highest quartile; 191 EMS agencies in each quartile). There were 82 EMS agencies working in Black/Hispanic communities overall, with 26 (31.7%) in the lowest RSSR quartile and 15 (18.3%) in the highest. After further adjustment for agency-level rates of bystander CPR, EMS response time and termination of resuscitation practices, there remained 29 (35.4%) EMS agencies in the lowest RSSR quartile and 16 (19.5%) in the highest. Conclusion: EMS agencies working in Black and Hispanic communities have lower prehospital survival for OHCA, although high-performing agencies exist. Identifying best practices at EMS agencies with the highest prehospital survival rates, particularly among agencies serving Black and Hispanic communities, has the potential to improve overall OHCA survival and reduce existing survival disparities.

Abstract 10908: The Association of Duration of Resuscitation and Long-Term Survival and Functional Outcomes After Out-of-Hospital Cardiac Arrest

Introduction: Longer emergency medical system (EMS) CPR-to-ROSC interval has been shown to be linearly associated with worse hospital discharge outcomes for out-of-hospital cardiac arrest (OHCA). We hypothesized that this association extends post-discharge in hospital survivors. We investigated whether pre-arrest co-morbidities influence the duration of resuscitation. Methods: We included EMS-treated adult OHCA (Jan 2009 - Dec 2016) from British Columbia Cardiac Arrest Registry and provincial databases. Pre-OHCA characteristics were compared by ≤ 10, 10-20, and >20 min CPR-to-ROSC interval categories. Outcomes included survival and functional outcomes at hospital discharge and 1-year, as well as 3-year post-discharge survival. We examined the relationship between CPR-to-ROSC interval categories and 1 and 3-year survival using Kaplan-Meier (KM). We examined the relationship between the CPR-to-ROSC interval (continuous variable) with all outcomes using regression models. Results: Among 10,241 OHCA, 4604 (45%) achieved ROSC, with a median CPR-to-ROSC interval of 15.5 (IQR 9.0- 22.9) min. Diabetes, chronic kidney disease, and prior MI were associated with longer CPR-to-ROSC intervals. 1245 (12.2%) survived to hospital discharge. Among hospital survivors, KM survival at 1- and 3- years were 92% [95% CI 90-93%] and 84% [95% CI 82-86%] respectively; survival curves stratified by CPR-to-ROSC intervals were not statistically different (Figure). Longer CPR-to-ROSC interval was non-linearly associated with lower survival and functional outcomes at hospital discharge but not with post-discharge outcomes. Conclusion: Longer CPR-to-ROSC interval was associated with lower survival at hospital discharge and is influenced by pre-arrest co-morbidities. However, these intervals were not associated with long-term survival or functional outcome among hospital survivors, suggesting that the early risk of longer CPR-to-ROSC intervals does not persist.

Abstract 257: Epidemiological Trends In Mean Age At Cardiac Arrest

Background: Nearly 1000 cardiac arrest cases are reported in the US every day, and 70-90% of the cases die before reaching the hospital. In this study, we aimed to describe trends in mean age of cardiac arrest in Chicago. Method: We analyzed adult out-of-hospital cardiac arrest (OHCA) cases reported to Cardiac Arrest Registry to Enhance Survival (CARES) database and served by Chicago Emergency Medical Services from 2014-2021. We excluded pediatric cases, and cases with missing age. The annual data were combined to create two-year cycles. The trends in the mean age of cardiac arrest cases were calculated using linear regression models. Results: 21,532 OHCA cases occurred during 2014-2021, and 61% were males, 57% Black, 26% White, 12% Hispanic/Latino and 5% Others. The mean age of OHCA was 62.9 years. The mean age decreased from 64.7 (in 2014-2015) to 61.5 (in 2020-2021) with a biennial change of -1.1 (p<0.01). The median age followed the same pattern with a decrease from 65 (in 2014-2015) to 62 years (in 2020-2021). Similar trends were noticed by gender. The mean age decreased in males (biennial change of -1.2; p<0.01) and in females (biennial change=-0.6; p<0.01) but was less pronounced in females. The mean age decreased significantly in White, Black, and Hispanic/Latino cases. However, in Asian cases, even though a decrease was noticed, it was not statistically significant. The largest decrease in mean age was in Black cases (biennial change of -1.2; p<0.01), followed by Hispanic/Latino cases (-0.7; p=0.03). When examined by race/ethnicity and gender, Black male cases had the largest decrease in mean age at cardiac arrest (-1.4; p<0.01). Conclusion: This analysis presents a concerning trend and speaks to the need for additional research and surveillance mechanisms to identify people at risk for OHCA. Early age at cardiac arrest could mean more years of potential life lost (YPLL). Changes in YPLL and disability-adjusted life years should also be explored in future studies.

Abstract 182: The Incidence And Indication For Palliative Care Consultation In A Cohort Of Out Of Hospital Cardiac Arrest Patients

Introduction: The indications for palliative care consultation are varied and integration of palliative care is often left to physician discretion. We sought to describe the population of post-arrest patients who receive a palliative care consultation and identify common indications for the consultation. Methods: Our study is a single center retrospective chart review from the Colorado Cardiac Arrest Registry (CCAR) including 541 patients admitted to the ICU after OHCA. Data abstracted included race, sex, preferred language, age, placement of a palliative care consult and number of palliative care meetings. A chi-squared test was used to determine statistical significance with a cutoff p value <0.05. Each palliative care consultation was reviewed and the indication for palliative care consultation was coded using thematic analysis. Results: Of the 541 patients in the study sample, a palliative care consult order was placed for 73 (13.5%) patients and 55 (10.2%) patients had at least one documented palliative care meeting. Code status changed after the first palliative care meeting in 4 patients. When comparing men to women, 15% of men and 11% of women received a consult. A consult was placed in 18.7% of patients identifying as Hispanic, compared to 13.9% in white patients and 12.6% in black patients. In patients whose preferred language was not English or Spanish, 28.6% received a consult compared to 13.5% of patients preferring English or Spanish. None of these differences were statistically significant. The most common themes identified as the indication for the palliative care consultation were 1.) conflict between the physician and family; 2.) low health literacy; 3.) within family discordance on goals of care and; 4.) the need for specialty social work such as assistance with hospice planning. Conclusions: Our study found a low incidence of palliative care consultation and more frequent consultation for non-English or Spanish speaking patients, with four major prevailing themes. Further study is needed to better understand and optimize the utilization of palliative care consultation in post-cardiac arrest patients.

Abstract 122: The Impact Of The Covid-19 Pandemic On The Incidence Of Ems Treated Out-of-hospital Cardiac Arrest Patients And The Incidence Of Bystander Cardiopulmonary Resuscitation (cpr); A World-wide Perspective

Introduction: Survival after OHCA is dependent on early recognition, early cardiopulmonary resuscitation (CPR) and early defibrillation. The purpose of CPR is to maintain some blood flow until the arrival of the emergency medical services (EMS). Our concern was that the Covid-19 pandemic would have a negative effect on the number of patients who got CPR before EMS arrival. The aim of this study is to compare the incidence of EMS treated patients and the incidence of bystander CPR during the pandemic with data from before the pandemic. Method: This is a retrospective cohort study using data from existing cardiac arrest registries. The participants are from 24 countries, where Australia and USA have four regions each, resulting in 30 individual participants. All participating registries share aggregated data from 2017 to 2020, and results from before and after lockdown is compared. Poisson regression was used to look at differences. Results: Preliminary results from 14 registries show that the incidence of EMS treated patients per 100.000 inhabitants was statistically increased in five registries, decreased in three registries, and had no statistical difference in six registries. The incidence of bystander CPR was statistically higher after lockdown in five registries, decreased in one registry and was unchanged in eight registries. Four regions had an increase in both incidence of EMS treated patients and the incidence of bystander CPR. Conclusion: Bystanders willingness to perform CPR seems unchanged by the Covid-19 pandemic.

Abstract 123: Bystander Cpr Usage In Out-of-hospital Cardiac Arrest During The Covid-19 Pandemic: Results From The Northeast Georgia Cardiac Arrest Registry

Background: During the COVID-19 pandemic, a higher incidence of out-of-hospital cardiac arrest (OHCA) has been reported but rates of bystander CPR usage have not been studied. Due to the COVID-19 pandemic, bystanders may be reluctant to perform CPR due to risk of infection and due to social isolation measures, there may be less bystanders present to perform CPR.Objective: The purpose of the study was to study rates of bystander CPR usage in out-of hospital cardiac arrest (OHCA) during the COVID-19 pandemic and to evaluate for any association between bystander CPR usage and increasing COVID-19 infection during 2020 and 2021. Methods: We performed a retrospective study of the Northeast Georgia Cardiac Arrest Registry to compare bystander CPR usage for all patients presenting to Northeast Georgia Medical Center in Gainesville, Georgia with OHCA from 14 surrounding counties of northeast Georgia from March 2019 to December 2021. Results: A total of 18,421 and 18,678 COVID-19 infections were reported in Hall County between Mar-Dec 2020 and Jan-Dec 2021, respectively. A total of 228 cardiac arrests occurred in 2019, 273 in 2020, and 268 in 2021. Overall bystander CPR usage was 44% in 2019, 43% in 2020, and 47% in 2021, p = .64. Before COVID-19 the bystander CPR usage was 43% and 46% during, p = 0.44. There was no significant correlation between bystander CPR usage and COVID-19 infections in Hall County (r = 0.06, p = 0.79). Multivariable logistic regression model demonstrated that initial shockable rhythm (p < 0. 001) was the strongest predicator of bystander CPR (table 1). Conclusions: Bystander CPR usage in OHCA in the northeast Georgia region remained constant despite the COVID-19 pandemic. There were no significant differences in bystander CPR usage in OHCA prior to or during COVID-19 pandemic. Additional studies are needed to evaluate for possible variables which may be contributing to initial shockable rhythm as the strongest predicator of bystander CPR.

Abstract 295: Availability Of Automatic Defibrillators And Volunteer Responders For Out-of-hospital Cardiac Arrest In Denmark

Introduction: Public automatic defibrillators (AEDs) and bystander resuscitation (CPR) are critical for cardiac arrest survival. We examined how availability of AEDs and volunteer responders that can be summoned with an app have developed following many national initiatives to improve survival. Methods: All OHCA (Out-of-Hospital Cardiac Arrest) registered with coordinates within the Danish Cardiac Arrest Registry (2016-2020) were included. This study assessed coverage of 1) AEDs and 2) volunteer responders at 12 noon for home and public OHCAs. Coverage was defined as ≥ 1 AED and ≥ 4 volunteer responders within 200, 500, or 1,800 meters using straight line distance from the OHCA. Results: A total of 22,330 OHCAs were included. At 12 noon, 33,180 volunteer responders (572/100,000 inhabitants) and 22,418 AEDs (387/100,000 inhabitants) were available. More OHCA were covered with AEDs compared to volunteer responders for all distances. A significant difference was found in AED coverage in public compared to home arrests for all distances (p for difference at all distances <0.05). Opposite, no difference was found in volunteer responder coverage for home compared to public arrests at 1,800 and 500 meters (p for difference >0.05). Figure 1 illustrates AED and volunteer responder coverage for home and public arrest. Conclusion: Following the implementation of a national volunteer responder program and strategic placement of AEDs in Denmark, most historical OHCAs were covered by AEDs and volunteer responders within 1,800 meters. Although we have more volunteer responders per 100,000 inhabitants compared to AEDs, we found more than half (53%) of all OHCA were covered with AEDs within 200 meters whereas only 16% of all OHCAs were covered by volunteer responders within 200 meters. These findings indicate strategic AED placement in Denmark, but further efforts regarding volunteer responder recruitment are needed to increase coverage of the historical OHCA in Denmark.

Alignment of targeted temperature management treatment with patients’ mortality risk for out-of-hospital cardiac arrest

ObjectiveTo examine whether TTM treatment was aligned with predicted mortality risk in patients with resuscitated OHCA during a period when it was a class I guideline-recommended therapy. MethodsWithin the Cardiac Arrest Registry to Enhance Survival for OHCA, we identified adult patients with OHCA who survived to hospital admission and were presumed eligible for TTM. Multivariable models were constructed using pre-hospital variables to predict in-hospital death in patients with shockable and non-shockable rhythms. Within each rhythm category, we divided patients into deciles of predicted mortality risk and examined TTM treatment rates across deciles. ResultsFrom 2013-2019, there were 25,882 successfully resuscitated patients with shockable rhythms and 43,414 patients with non-shockable rhythms presumed eligible for TTM. Of patients with shockable rhythms, predicted in-hospital mortality ranged from 16%–78% in deciles 1–10. TTM treatment increased from 44% in decile 1 to 59% in decile 10 (P for trend < 0.001), but over a third of patients in deciles 4–9 were not treated with TTM. Of patients with non-shockable rhythms, predicted mortality ranged from 48%-95% in deciles 1–10. Although TTM treatment rates increased from 36% in decile 1 to 43% in decile 10 (P for trend 0.003), TTM treatment rates were agnostic to mortality risk (44% to 47%) from decile 2–9. ConclusionTTM treatment patterns were not well-aligned with patients’ mortality risk during a period when it was a guideline-recommended treatment for OHCA. Identifying strategies to better align guideline-recommended treatments with patients’ mortality risk is critical for efforts to improve OHCA survival.

Symptoms reported in calls to emergency medical services within 24 hours prior to out-of-hospital cardiac arrest

AimThere is limited evidence regarding prodromal symptoms of out-of-hospital cardiac arrest (OHCA). We aimed to describe patient characteristics, prodromal symptoms, and prognosis of patients contacting emergency medical services (EMS) within 24 hours before OHCA. MethodsWe identified all OHCA treated by Copenhagen EMS from 2016 through 2018 using the Danish Cardiac Arrest Registry and linked them to emergency calls. We included all pre-arrest calls by patients or bystanders if they were performed 1) within 24 hours before the OHCA call or 2) during the OHCA event for EMS-witnessed OHCA. Calls were reviewed by healthcare professionals using a survey guide. ResultsAmong 4,071 patients, 481 patients (12 %) had 539 calls within 24 hours prior to OHCA (60 % male, median age 74 years of age). The patient spoke on the phone in 25 % of calls. The most common symptoms were breathing problems (59 %), confusion (23 %), unconsciousness (20 %), chest pain (20 %), and paleness (19 %). Patients with breathing problems compared to chest pain were more likely to be ≤ 75 years of age (55 % versus 35 %), less likely to be male (52 % versus 73 %), have shockable rhythm (10 % versus 38 %), receive bystander defibrillation (6 % versus 19 %) or EMS defibrillation (15 % versus 65 %), achieve return of spontaneous circulation (37 % versus 68 %) and survive 30 days following OHCA (10 % versus 50 %). ConclusionMore than 10% of patients with OHCA had a call to EMS within 24 hours before OHCA. The most common symptom was breathing problems which compared to chest pain had lower 30-day survival.

Long-term Mortality, Readmission, and Resource Utilization Among Hospital Survivors of Out-of-Hospital Cardiac Arrest.

Among patients with out-of-hospital cardiac arrest (OHCA), the influence of pre- and in-hospital factors on long-term survival, readmission, and resource utilization is ill-defined, mainly related to challenges combining disparate data sources. Adult nontraumatic OHCA from the British Columbia Cardiac Arrest Registry (January 2009 to December 2016) were linked to provincial datasets comprising comorbidities, medications, cardiac procedures, mortality, and hospital admission and discharge. Among hospital-discharge survivors, the 3-year end point of mortality or mortality and all-cause readmission was examined with the use of the Kaplan-Meier method and multivariable Cox regression model for predictors. The use of publicly funded home care and community services within 1 year after discharge also was evaluated. Of the 10,674 linked, emergency medical services-treated adult OHCAs, 3230 were admitted to hospital and 1325 survived to hospital discharge. At 3 years after discharge, the estimated Kaplan-Meier survival rate was 84.1% (95% CI 81.7%-86.1%) and freedom from death or all-cause readmission was 31.8% (29.0%-34.7%). After exclusions, 26.6% (n= 315/1186) accessed residential or home care services within 1 year. Independent predictors of long-term outcomes included age and comorbidities, but also favourable arrest characteristics and in-hospital factors such as revascularization or receipt of an intracardiac defibrillator before discharge. Among OHCA hospital survivors, the long-term death or readmission risk persists and is modulated by both pre- and in-hospital factors. However, only 1 in 4 survivors required residential or home care after discharge. These results support efforts to improve care processes to increase survival to hospital discharge.

The impact of COVID-19 pandemic on out-of-hospital cardiac arrest system-of-care: Which survival chain factor contributed the most?

ObjectivesIn many communities, out-of-hospital cardiac arrest (OHCA) survival outcomes decreased after the coronavirus disease 2019 (COVID-19) pandemic. This study aimed to identify and compare the impacts of each survival chain factor on the change of survival outcomes after COVID-19. MethodsUsing a Korean out-of-hospital cardiac arrest registry, we analyzed OHCA patients whose arrest was not witnessed by emergency medical service (EMS) providers between 2017 and 2021. Because lack of hospital and survival information in 2021, the 2021 data were used only to identify the expected trend. We developed a prediction model for survival to discharge using patients from 2017 to 2019 (Pre-COVID-19 set) and validated it using patients from 2020 (post-COVID-19 set). Using Utstein elements, a stepwise logistic regression model was constructed, and discrimination and calibration were evaluated by c-statistics and scaled Brier score. Using the distribution change of predictors from one year before the pandemic (2019) to post-COVDI-19, we calculated the magnitude of survival difference according to each predictor's distribution change using the marginal standardization method. ResultsAmong 83,273 patients (mean age 67.2 years and 64.3% males), 61,180 and 22,092 patients belonged to pre-COVOD-19 and post-COVID-19 sets. Survival to discharge was 5019 (8.2%) in pre-COVID-19 set and 1457 (6.6%) in post-COVID-19 set. The proportion of bystander cardiopulmonary resuscitation was 59.0% in the pre-COVID-19 set and 61.0% in the post-COVID-19 set. The median (interquartile range) response time was 7 (5–9) minutes in the pre-COVID-19 set and 8 (6–10) minutes in the post-COVID-19 set. The area under the receiver operating characteristic (AUROC) curve (95% confidence interval) was 0.907 (0.902–0.912) in the pre-COVID-19 set, and 0.924 (0.916–0.931) in the post-COVID-19 set, and scaled Brier score were 0.39 in pre-COVID-19 sets, and 0.40 in the post-COVID-19 set. Among various predictors, EMS factors showed the highest impact. Response time and on-scene management of EMS showed the highest impact on decreased survival. A similar trend was also expected in the 2021. ConclusionThe effort to create a rapid response system for OHCA patients could have priority for the recovery of survival outcomes in OHCA patients in the post-COVID-19 period. Further studies to recover survival outcomes of OHCA are warranted.

Machine learning analysis to identify data entry errors in prehospital patient care reports: a case study of a national out-of-hospital cardiac arrest registry

Background: To develop and validate machine learning models for data entry error detection in a national out-of-hospital cardiac arrest (OHCA) prehospital patient care report database. Methods: Adult OHCAs of presumed cardiac etiology were included. Data entry errors were defined as discrepancies between the coded data and the free-text note documenting the intervention or event; for example, information that was recorded as “absent” in the coded data but “present” in the free-text note. Machine learning models using the extreme gradient boosting, logistic regression, extreme gradient boosting outlier detection, and K-nearest neighbor outlier detection algorithms for error detection within nine core variables were developed and then validated for each variable. Results: Among 12,100 OHCAs, the proportion of cases with at least one error type was 16.2%. The area under the receiver operating characteristic curve (AUC) of the best-performing model (model with the highest AUC for each outcome variable) was 0.71–0.95. Machine learning models detected errors most efficiently for outcome place and initial rhythm errors; 82.6% of place errors and 93.8% of initial rhythm errors could be detected while checking 11% and 35% of data, respectively, compared to the strategy of checking all data. Conclusion: Machine learning models can detect data entry errors in care reports of EMS clincians with acceptable performance and likely can improve the efficiency of the process of data quality control. EMS organizations that provide more prehospital interventions for OHCA patients could have higher error rates and may benefit from the adoption of error-detection models.

European Registry of Cardiac Arrest – Study-THREE (EuReCa THREE) – An international, prospective, multi-centre, three-month survey of epidemiology, treatment and outcome of patients with out-of-hospital cardiac arrest in Europe – The study protocol

BackgroundThe aim of the European Registry of Cardiac Arrest (EuReCa) network is to provide high quality evidence on epidemiology of out-of-hospital cardiac arrest (OHCA) in Europe by supporting and developing cardiac arrest registries and performing European-wide studies. To date, the EuReCa ONE and EuReCa TWO studies have involved around 28 countries, with population covered increasing from the first to the second study. The aim of the EuReCa THREE study is to build on previous work and to support the promotion of quality data collection on OHCA throughout Europe. Methods/designEuReCa THREE will be the third prospective cohort study on epidemiology of OHCA and will involve around 30 European countries. The study will be conducted between 1st September and 30th November 2022. Data will be collected on cardiac arrest cases attended, resuscitation attempted, patient and cardiac arrest event characteristics and outcomes (including return of spontaneous circulation, status on hospital arrival and discharge). A particular focus for EuReCa THREE will be to describe key time intervals in OHCA management; time from call to EMS arrival on scene, time from cardiac arrest to start CPR, time from EMS arrival to delivery of patient to hospital.EuReCa THREE was registered with the German Registry of Clinical Trials Registration Number: DRKS00028591 searchable via WHO meta-registry (https://apps.who.int/trialsearch/). DiscussionThe EuReCa THREE study will increase our knowledge on longitudinal OHCA epidemiology and provide new knowledge on crucial time intervals in OHCA management in Europe. However, the primary aim of building a network to support quality data on OHCA, remains the central tenant of the EuReCa project.

High dose of epinephrine does not improve survival of children with out-of-hospital cardiac arrest: Results from the French National Cardiac Arrest Registry.

ObjectivesThe pediatric resuscitation guidelines recommend the use of 0. 01 mg kg−1 epinephrine during a cardiac arrest; an epinephrine dose higher than that is not recommended. The first aim of this study was to determine the administration rate of high epinephrine dose during pediatric out-of-hospital cardiac arrest. The second aim was to compare the survival status in patients who received high or standard doses of epinephrine.MethodsThis was a multicenter comparative post-hoc study conducted between January 2011 and July 2021 based on the French National Cardiac Arrest Registry data. All prepubescent (boys < 12 years old, girls < 10 years old) victims of an out-of-hospital cardiac arrest were included. To compare survival status and control bias, patients who received a high epinephrine dose were matched with those who received a standard epinephrine dose using propensity score matching.ResultsThe analysis included 755 patients; 400 (53%) received a high dose and 355 (47%) received a standard dose of epinephrine. The median dose (mg kg−1) per bolus was higher in the high-dose group than that in the standard dose group (0.04 vs. 0.01 mg kg−1, P < 0.001). Before matching, there was no between-group difference in the 30-day survival rate or survival status at hospital discharge. Matching yielded 288 pairs; there was no between-group difference in the 30-day survival rate or survival at hospital discharge (High dose, n = 5; standard dose, n = 12; Odds ratios: 2.40, 95% confidence interval: 0.85–6.81). Only 2 patients in the standard dose group had a good neurological outcome.ConclusionMore than 50% of the patients did not receive the recommended epinephrine dose during resuscitation. There was no association between patients receiving a high dose or standard dose of epinephrine with the 30-day survival or survival status at hospital discharge. Collaboration across multiple cardiac arrest registries is needed to study the application of pediatric guidelines.