Emergency Medical Services Response Time Research Articles

Socioeconomic disadvantage and long-term survival duration in out-of-hospital cardiac arrest patients: A population-based cohort study

BackgroundSocioeconomic status (SES) is a well-established determinant of cardiovascular health. However, the relationship between SES and clinical outcomes in long-term out-of-hospital cardiac arrest (OHCA) is less well-understood. The Singapore Housing Index (SHI) is a validated building-level SES indicator. We investigated whether SES as measured by SHI is associated with long-term OHCA survival in Singapore. MethodsWe conducted an open cohort study with linked data from the Singapore Pan-Asian Resuscitation Outcomes Study (PAROS), and the Singapore Registry of Births and Deaths (SRBD) from 2010 to 2020. We fitted generalized structural equation models, calculating hazard ratios (HRs) using a Weibull model. We constructed Kaplan–Meier survival curves and calculated the predicted marginal probability for each SHI category. ResultsWe included 659 cases. In both univariable and multivariable analyses, SHI did not have a significant association with survival. Indirect pathways of SHI mediated through covariates such as Emergency Medical Services (EMS) response time (HR of low-medium, high-medium and high SHI when compared to low SHI: 0.98 (0.88–1.10), 1.01 (0.93–1.11), 1.02 (0.93–1.12) respectively), and age of arrest (HR of low-medium, high-medium and high SHI when compared to low SHI: 1.02 (0.75–1.38), 1.08 (0.84–1.38), 1.18 (0.91–1.54) respectively) had no significant association with OHCA survival. There was no clear trend in the predicted marginal probability of survival among the different SHI categories. ConclusionsWe did not find a significant association between SES and OHCA survival outcomes in residential areas in Singapore. Among other reasons, this could be due to affordable healthcare across different socioeconomic classes.

Prehospital Ground and Helicopter-Based Extracorporeal Cardiopulmonary Resuscitation (ECPR) Reduce Barriers to ECPR: A GIS Model

ABSTRACT Introduction Evidence suggests that Extracorporeal Cardiopulmonary Resuscitation (ECPR) can improve survival rates for nontraumatic out-of-hospital cardiac arrest (OHCA). However, when ECPR is indicated over 50% of potential candidates are unable to qualify in the current hospital-based system due to geographic limitations. This study employs a Geographic Information System (GIS) model to estimate the number of ECPR eligible patients within the United States in the current hospital-based system, a prehospital ECPR ground-based system, and a prehospital ECPR Helicopter Emergency Medical Services (HEMS)-based system. Methods We constructed a GIS model to estimate ground and helicopter transport times. Time-dependent rates of ECPR eligibility were derived from the Resuscitation Outcome Consortium (ROC) database, while the Cardiac Arrest Registry to Enhance Survival (CARES) registry determined the number of OHCA patients meeting ECPR criteria within designated transportation times. Emergency Medical Services (EMS) response time, ECPR candidacy determination time, and on-scene time were modeled based on data from the EROCA trial. The combined model was used to estimate the total ECPR eligibility in each system. Results The CARES registry recorded 736,066 OHCA patients from 2013 to 2021. After applying clinical criteria, 24,661 (3.4%) ECPR-indicated OHCA were identified. When considering overall ECPR eligibility within 45 minutes from OHCA to initiation, only 11.76% of OHCA where ECPR was indicated were eligible in the current hospital-based system. The prehospital ECPR HEMS-based system exhibited a four-fold increase in ECPR eligibility (49.3%), while the prehospital ground-based system showed a more than two-fold increase (28.4%). Conclusions The study demonstrates a two-fold increase in ECPR eligibility for a field-deployable ground-based system and a four-fold increase for a prehospital ECPR HEMS-based system compared to the current hospital-based OHCA system. This novel GIS model can inform future ECPR implementation strategies, optimizing systems of care.

Exploring paramedic perspectives on emergency medical service (EMS) delivery in Alberta: a qualitative study.

Emergency Medical Services (EMS) in Alberta are facing critical challenges. This qualitative study aims to describe and understand the frontline perspective regarding system level issues and propose provider-informed policy recommendations. 19 semi-structured one-on- one interviews were conducted with Primary or Advanced Care Paramedics (PCP/ACP) across Alberta. Participants were asked to share their perspectives, experiences and recommendations in relation to EMS response times and the working environment. Interviews were analyzed using thematic analysis to identify themes and subthemes. Two core themes were identified as areas of concern: poor response times and the EMS working environment, which each influence and impact the other. Within response times, paramedics highlighted specific difficulties with ED offloading, a lack of resources, low-acuity calls, and rural challenges. In terms of the EMS working environment, four subthemes were apparent including attrition, unhealthy culture, organizational barriers and the need for paramedic empowerment. Providers made many recommendations including creating and expanding emergency mobile integrated health (MIH) branches, sharing 811 and 911 responses, and enforcing ED target offload times amongst other suggestions. While response times are a key and highly visible problem, there are many critical factors like the EMS working environment that degrade patient care and cause concern amongst frontline practitioners. Multifaceted policy changes are to be explored to reduce disfunction within EMS services, enhance the well-being of the workforce and deliver improved patient care. Specific EMS-oriented policies are important for moving forward to reduce transfers to EDs, but the broader health system which is over capacity is causing downstream effects into EMS must be addressed by government and health administrators.

The prediction of the survival in patients with severe trauma during prehospital care: Analyses based on NTDB database.

Traumas cause great casualties, accompanied by heavy economic burdens every year. The study aimed to use ML (machine learning) survival algorithms for predicting the 8-and 24-hour survival of severe traumas. A retrospective study using data from National Trauma Data Bank (NTDB) was conducted. Four ML survival algorithms including survival tree (ST), random forest for survival (RFS) and gradient boosting machine (GBM), together with a Cox proportional hazard model (Cox), were utilized to develop the survival prediction models. Following this, model performance was determined by the comparison of the C-index, integrated Brier score (IBS) and calibration curves in the test datasets. A total of 191,240 individuals diagnosed with severe trauma between 2015 and 2018 were identified. Glasgow Coma Scale (GCS), trauma type, age, SaO2, respiratory rate (RR), systolic blood pressure (SBP), EMS transport time, EMS on-scene time, pulse, and EMS response time were identified as the main predictors. For predicting the 8-hour survival with the complete cases, the C-indexes in the test sets were 0.853 (0.845, 0.861), 0.823 (0.812, 0.834), 0.871 (0.862, 0.879) and 0.857 (0.849, 0.865) for Cox, ST, RFS and GBM, respectively. Similar results were observed in the 24-hour survival prediction models. The prediction error curves based on IBS also showed a similar pattern for these models. Additionally, a free web-based calculator was developed for potential clinical use. The RFS survival algorithms provide non-parametric alternatives to other regression models to be of clinical use for estimating the survival probability of severe trauma patients.

Promoting Emergency Medical Service Infrastructure Equality to Reduce Road Crash Fatalities

Timely emergency medical service (EMS) is critical to mitigate outcomes of severe traffic crashes, especially in rural areas. The urban–rural inequality of the EMS infrastructure has been one of the factors contributing to a higher death rate for patients in rural road crashes. To address the spatial imbalance of EMS infrastructure, this study aimed to provide a methodological framework for evaluating the existing EMS infrastructure by taking South Korea’s EMS infrastructure expansion plans as the case study. Specifically, this study developed a road crash data-driven methodology to promote spatial balance and economical expansion of EMS infrastructure of all types, including EMS stations, hospitals, the helicopter fleet, and landing spots. Geographically weighted binary logit regression and spatial analysis identified strategic locations for prioritizing the EMS infrastructure expansion using crash victim data and road networks to close the gap between urban and rural areas. The analysis of access to existing EMS infrastructure showed that the 16 to 20 min EMS response time, including on-scene time and transport time ranging from 11 to 15 min, are significantly associated with higher crash fatalities. The results also suggested that EMS stations and heliports are inadequate to meet the EMS time thresholds in the central province of Korea. The findings of this research could inform policymakers as they are working toward expanding the EMS infrastructure and creating a more equitable EMS response when it comes to transporting rural road crash patients.

Association between prehospital time and in-hospital outcomes in out-of-hospital cardiac arrests according to resuscitation outcomes consortium epidemiologic registry

IntroductionFor out-of-hospital cardiac arrests (OHCAs), time is of the essence. While the relationship between EMS response time (ERT) and OHCA outcomes is well studied, a more comprehensive assessment of the effects of other intervention time is needed, which is essential to guide clinical practice. ObjectivesEvaluating how a longer total pre-hospital time (TPT), ERT, advance life support response time (ART) and EMS cardiopulmonary resuscitation time (ECT) increase the mortality rates, unfavorable neurological outcomes, and severe complications at discharge of OHCAs. Methods31,926 OHCAs from the USA and Canada were identified in Resuscitation Outcomes Consortium Epidemiologic Registry. Twelve adjusted models were used to analyze the relationship between the prehospital time (TPT, ERT, ART and ECT) and three outcomes (in hospital mortality, unfavorable neurological outcomes, and severe complications for surviving OHCAs). ResultsEvery 10-min increase in TPT was associated with a 0.14-fold increase in the risk of death (adjusted odds ratio [OR] = 1.14, 95 % confidence interval [CI] = 1.10–1.17) and a 0.13-fold increase of adverse neurological outcomes (OR = 1.13, CI =1.08–1.18). The risk of patient mortality markedly increased with every 5 min increase in ERT (OR = 1.36, CI = 1.26–1.47), ART (OR =1.10, CI = 1.06–1.15), and ECT (OR = 1.46, CI = 1.37–1.56). Adverse neurological outcome was associated with ERT and ECT, and severe complications with ERT and ART. ConclusionProlonged prehospital time, particularly ERT and ECT, are closely associated with in-hospital mortality, unfavorable neurological functions, and severe complications at discharge in OHCAs.

Impact of the COVID-19 pandemic on prehospital and in-hospital treatment and outcomes of patients after out-of-hospital cardiac arrest: a Japanese multicenter cohort study

BackgroundIn the chain of survival for Out-of-hospital cardiac arrest (OHCA), each component of care contributes to improve the prognosis of the patient with OHCA. The SARS-CoV-2 (COVID-19) pandemic potentially affected each part of care in the chain of survival. The aim of this study was to compare prehospital care, in-hospital treatment, and outcomes among OHCA patients before and after the COVID-19 pandemic.MethodsWe analyzed data from a multicenter prospective study in Kanto area, Japan, named SOS-KANTO 2017. We enrolled patients who registered during the pre-pandemic period (September 2019 to December 2019) and the post-pandemic period (June 2020 to March 2021). The main outcome measures were 30-day mortality and the proportion of favorable outcomes at 1 month, and secondary outcome measures were changes in prehospital and in-hospital treatments between the pre- and post-pandemic periods.ResultsThere were 2015 patients in the pre-pandemic group, and 5023 in the post-pandemic group. The proportion of advanced airway management by emergency medical service (EMS) increased (p < 0.01), and EMS call-to-hospital time was prolonged (p < 0.01) in the post- versus pre-pandemic group. There were no differences between the groups in defibrillation, extracorporeal membrane oxygenation, or temperature control therapy (p = 0.43, p = 0.14, and p = 0.16, respectively). Survival rate at 1 month and favorable outcome rate at 1 month were lower (p = 0.01 and p < 0.01, respectively) in the post- versus pre-pandemic group.ConclusionSurvival rate and favorable outcome rate 1 month after return of spontaneous circulation of OHCA worsened, EMS response time was prolonged, and advanced airway management by EMS increased in the post- versus pre-pandemic group; however, most prehospital and in-hospital management did not change between pre- and post-COVID-19 pandemic.

AgroGuardian: An All-Terrain Vehicle Crash Detection and Notification System

Highlights Off-road ATV incidents can be problematic due to long EMS alert times. An ATV crash-detection-and-report system is expected to reduce EMS response time. The developed system can accurately detect ATV rollovers. The alert time of our system is 10 times faster than the national U.S. average. Any rider using our system is 3 times more likely to survive an off-road crash. Abstract. All-Terrain Vehicle (ATV) incidents are a common cause of injury and death in the agricultural industry in the United States. Many ATV off-road crashes on farms and ranches may result in trauma requiring immediate care, but the injured rider is unable to seek help due to their injuries. Moreover, many of these crashes occur in isolated areas that may be difficult to access and have unreliable cellular phone service, making contact with emergency medical services (EMS) challenging. This study aimed at developing and testing a low-cost ATV crash detection device (AgroGuardian) that immediately alerts EMS and emergency contacts, even when the rider is unable to take action and/or there is no cellular phone service available. AgroGuardian includes an embedded data logging system, a smartphone application, and a remote database. The embedded system includes an Inertial Measurement Unit (IMU) for attitude estimation, a Global Positioning System (GPS) for location estimation, and a Rock7 modem for off-board communication. A smartphone application was developed for the users to input information about their vehicle (e.g., make and model) and emergency contacts. Also, it allows them to interact with their ATV data. An emergency signal along with the ATV’s coordinates is transmitted through the Rock7 modem and received in the remote database when a rollover is detected by the system. This emergency signal is then processed and sent to EMS and emergency contacts. Our results indicated that the device: (1) is unlikely to miss an ATV rollover; (2) has a fast EMS notification time (40.7 s); and (3) the ATV localization system presented an average error of 2.34 m. Keywords: ATV, EMS alert time, Farm, Off-road incidents, Quadbike, Rollover.

Characteristics, survival and neurological outcome in out-of-hospital cardiac arrest in young adults in Sweden: A nationwide study

AimThe aim of this study was to present a comprehensive overview of out-of-hospital cardiac arrests (OHCA) in young adults. MethodsThe data set analyzed included all cases of OHCA from 1990 to 2020 in the age-range 16–49 years in the Swedish Registry of Cardiopulmonary Resuscitation (SRCR). OHCA between 2010 and 2020 were analyzed in more detail. Clinical characteristics, survival, neurological outcomes, and long-time trends in survival were studied. Logistic regression was used to study 30-days survival, neurological outcomes and Utstein determinants of survival. ResultsTrends were assessed in 11,180 cases. The annual increase in 30-days survival during 1990–2020 was 5.9% with no decline in neurological function among survivors. Odds ratio (OR) for heart disease as the cause was 0.55 (95% CI 0.44 to 0.67) in 2017–2020 compared to 1990–1993. Corresponding ORs for overdoses and suicide attempts were 1.61 (95% CI 1.23–2.13) and 2.06 (95% CI 1.48–2.94), respectively. Exercise related OHCA was noted in roughly 5%. OR for bystander CPR in 2017–2020 vs 1990–1993 was 3.11 (95% CI 2.57 to 3.78); in 2020 88 % received bystander CPR. EMS response time increased from 6 to 10 minutes. ConclusionSurvival has increased 6% annually, resulting in a three-fold increase over 30 years, with stable neurological outcome. EMS response time increased with 66% but the majority now receive bystander CPR. Cardiac arrest due to overdoses and suicide attempts are increasing.

Bystander defibrillation increases 30-day survival even with short emergency medical service response time

Abstract Background Rates of bystander initiated defibrillation are increasing in many areas of the world (1-4), but the effect of defibrillation at different time points after recognition of out-of-hospital cardiac arrest (OHCA) remains largely unknown. Purpose To assess the effect on 30-day survival of bystander defibrillation at different intervals of emergency medical service (EMS) response time. Methods We included OHCAs from 2016 through 2020 from the Danish Cardiac Arrest Registry. Cases were included if they were ≥18 years of age, bystander witnessed, received bystander cardiopulmonary resuscitation (CPR), had EMS response time of 25 minutes or less and only the first OHCA for each subject was considered. We excluded cases witnessed by EMS or if they had missing values of OHCA-related variables. Crude survival proportions were calculated for each minute of EMS response time. Relative risks (RR) and corresponding 95 % confidence intervals (95 % CI) of the outcome (30-day survival) for eight different intervals of EMS response time were estimated using a causal inference framework utilizing Targeted Maximum Likelihood Estimation (TMLE) with ensemble Super Learning, adjusting for age, sex, place of arrest (public/private), initial cardiac rhythm (shockable/not shockable), and comorbidities (prior acute myocardial infarction, ischemic heart disease, heart failure, chronic obstructive pulmonary disease, stroke, cancer). Results We included 7,471 cases of bystander witnessed OHCA receiving CPR before EMS arrival. Of these, 14.7 % (1,098/7,471) received bystander defibrillation before arrival of EMS. Overall, 44.5 % (489/1,098) survived to 30 days when bystander defibrillation was performed versus 18.8 % (1,200/6,373) when no bystander defibrillation was performed. When examining the crude survival proportion for each minute of EMS response time, we found that 30-day survival was consistently higher in the group receiving bystander defibrillation for the first 20 minutes after which the survival was approximately the same for the two groups (Figure 1). When adjusting for confounders, we found statistically significantly increased relative risks of 30-day survival for patients receiving bystander defibrillation, compared to patients not bystander defibrillated, for all intervals of EMS response time, except for response times of 0-2 min., where the increase did not reach statistical significance (0-2 min: RR; 1.34 [95 % CI: 0.88-2.05], 2-4 min: RR; 1.37 [95 % CI: 1.10-1.70], 4-6 min: RR; 1.55 [95 % CI: 1.33-1.80], 6-8 min: RR; 2.23 [95 % CI: 1.86-2.67], 8-10 min: RR; 1.99 [95 % CI: 1.55-2.55], 10-12 min: RR; 1.89 [95 % CI: 1.34-2.68], 12-15 min: RR; 1.86 [95 CI: 1.22-2.84], &amp;gt;15 min: RR; 1.98 [95 % CI: 1.16-3.38]) (Figure 2). Conclusion For all intervals of EMS response time, bystander defibrillation increased 30-day survival of OHCA. The effect was significant for EMS response times as short as 2-4 minutes.

Exploring underlying reasons for the difference in sex-specific survival following out-of-hospital cardiac arrest - a mediation analysis

Abstract Background Previous studies have indicated a poorer survival among women following out-of-hospital cardiac arrest (OHCA), but the mechanisms explaining this difference remains largely uncertain. This study aimed to assess the survival after OHCA among women men and explore the role of potential mediators, such as resuscitation characteristics, prior comorbidity, and socioeconomic factors. Methods This was a population-based cohort study including all emergency medical service-treated OHCA reported to the Swedish Registry for Cardiopulmonary Resuscitation in 2010-2020, linked to nationwide Swedish healthcare registries. The relative risks (RR) of 30-day survival were compared among women (exposure) and men (comparison) using modified Poisson regression and third variable effect analysis to investigate the importance of potential mediators in a stepwise approach. Results A total of 43,226 OHCAs were included, of which 14,249 (33.0%) were women. The crude 30-day survival among women was 6.2% compared to 10.6% for men (RR 0.58, 95% CI=0.54-0.62). Stepwise adjustment for shockable initial rhythm attenuated the association to RR 0.85 (95% CI=0.80-0.92), and further adjustments for age and resuscitation factors (witness status, emergency medical service response time, and location) attenuated the survival difference between sexes to null (RR 0.98; 95% CI=0.92-1.05). Third variable effect analysis showed that shockable initial rhythm explained approximately 50% of the negative association of female sex on survival. Older age and lower disposable income were the second and third most important variables. Previously known comorbidities explained only a very small portion of the sex difference in survival. Conclusion Women have a lower 30-day survival following OHCA compared to men. The poor prognosis is largely explained by the absence of shockable initial rhythm, older age at presentation and lower disposable income.Results from regression analyses

Abstract 421: Automated External Defibrillator Implementation Gaps in Three Non-Urban U.S. Communities

Introduction: Automated external defibrillators (AEDs) represent a crucial component of bystander response to out-of-hospital cardiac arrest (OHCA), yet epidemiologic evidence suggests that AEDs are deployed by laypersons in less than 5% of OHCA events in the US. The reasons for low utilization remain poorly characterized, especially in rural/suburban environments. We hypothesized that in these non-urban environments, layperson AED use is mostly in commercial or public locations despite most arrests occuring in private residences. Methods: We conducted an analysis of EMS-treated atraumatic OHCA events from 3 non-urban US regions (Cumberland County, PA; Jackson, TN; Forsyth County, GA), abstracted from EMS patient care reports. Data included Utstein reporting elements, arrest location type, and response intervals as calculated by dispatch and EMS arrival times. We excluded events in skilled nursing facilities and prisons. CPR and AED delivery by laypersons was measured. Results: Between 12/8/17-12/31/21, we identified 1542 adult OHCA patients with median age 66.5 y (IQR 22.5), 37% female, 18% had initial shockable rhythms, and 75% occurred in private residences. Return of spontaneous circulation was obtained in 19% of cases. Bystander CPR was performed in 23% and AEDs were deployed by laypersons in 3%. Laypersons applied AEDs in 12% of OHCA in commercial locations, 6% of OHCA in public, and 3% of OHCA in private residences. EMS response times were 4% less than 4 min, 48% 4-9 min, and 48% &gt;9 min; prevalence of AED use was indistinguishable between time intervals of EMS response. 16% OHCA victims still had initial shockable rhythms even among the &gt;9 min EMS response cases; of these, 1% received AED use from laypersons. Conclusion: In three non-urban US regions, most arrests occurred in private residences while AED use was much more likely in public or commercial locales, suggesting an important gap in AED deployment. Even in cases with prolonged response times, many patients had shockable rhythms, suggesting an important opportunity for earlier AED deployment. Future work will test whether placement of AEDs in residential areas using trained volunteer responders in these same communities will improve OHCA response and survival outcomes.

Abstract 336: Bystander CPR Maintains Shockable Rhythm in Sudden Cardiac Arrest Across EMS Response Times

Introduction: Presentation with shockable rhythm markedly improves survival from out-of-hospital sudden cardiac arrest (SCA). Shockable rhythms (ventricular fibrillation/tachycardia; VF/VT) are known to deteriorate to asystole or pulseless electrical activity (PEA) over time, but little population-based data is available regarding this phenomenon. Also, bystander CPR (BCPR) improves survival from SCA but its association with maintenance of shockable rhythms is unclear. Hypothesis: With longer EMS response time, the proportion of EMS-assessed shockable initial rhythms will decrease. BCPR may influence this association. Methods: We analyzed EMS-assessed initial rhythm of SCA cases from the Oregon SUDS study in the Portland, OR metro area (pop ~1 million). For this analysis, we included bystander-witnessed SCA cases (2002-2018) aged ≥18 with resuscitation attempted by EMS. SCA was defined as a sudden, unexpected pulseless condition of likely cardiac origin. We assessed initial rhythm proportions across EMS response times using Cochran-Armitage trend tests. Results: Among 3,309 SCA cases, 1,748 (53%) were bystander-witnessed, and of these, 706 (40%) received BCPR. Response time was 7.3 ± 3.4 minutes for cases with BCPR and 6.8 ± 3.1 minutes without BCPR (p=0.01). In the group receiving BCPR, the proportion with shockable rhythm remained near 60% across response times from &lt;3 to ≥12 minutes (Figure, solid line; p=0.88), and proportions of PEA and asystole remained stable. In the group without BCPR, shockable rhythm declined from 70% at &lt;3 minutes to 44% at ≥12 minutes response time (Figure, dashed line; p&lt;0.001), while non-shockable rhythms increased. Conclusions: Among community-based SCA cases who received bystander CPR, there was no significant decrease in shockable rhythm as response time increased. In contrast, among SCA cases without bystander CPR, longer response times were associated with a lower proportion of shockable rhythms.

Abstract 380: Prehospital Ground and Helicopter-Based Extracorporeal Cardiopulmonary Resuscitation (ECPR) Reduce Barriers to ECPR: A GIS Model

Introduction: Evidence suggests that ECPR can improve survival rates for nontraumatic out-of-hospital cardiac arrest (OHCA). However, over 50% of potential ECPR candidates are unable to qualify in the current hospital-based system due to geographic limitations. This study employs a Geographic Information System (GIS) model to estimate the number of ECPR eligible patients within the U.S. in the current hospital-based system, a prehospital ECPR ground-based system, and a prehospital ECPR HEMS-based system (Figure 1). Methods: We constructed a GIS model to estimate ground and helicopter transport times. Time-dependent rates of ECPR eligibility were derived from the Resuscitation Outcome Consortium (ROC) database, while the Cardiac Arrest Registry to Enhance Survival (CARES) registry determined the number of OHCA patients meeting ECPR criteria within designated transportation times. EMS response time, ECPR candidacy determination time, and on-scene time were modeled based on data from the EROCA trial (Figure 1). The combined model was used to estimate the total ECPR candidates in each system. Results: The CARES registry recorded 736,066 OHCA patients from 2013 to 2021. After applying clinical eligibility criteria, 24,661 (3.4%) patients were eligible for ECPR. When considering overall ECPR eligibility within 45 minutes from OHCA to initiation, only 11.76% of clinically eligible patients qualified in the current hospital-based system. The prehospital ECPR HEMS-based system exhibited a four-fold increase in ECPR eligibility (49.3%), while the prehospital ground-based system showed a more than two-fold increase (28.4%). Conclusions: The study demonstrates a two-fold increase in ECPR eligibility for a field-deployable ground-based system and a four-fold increase for a prehospital ECPR HEMS-based system compared to the current hospital-based OHCA system. This novel GIS model can inform future ECPR implementation strategies, optimizing systems of care.

Abstract 231: Assessing the Effectiveness of Food Delivery Service Integration for Automated External Defibrillator Delivery in Out-of-Hospital Cardiac Arrest Response Through Computer Simulation

Background: The number of food delivery (FD) motorcycle riders in Taipei has rapidly increased. These riders often wait near popular restaurants during rush hours and could potentially act as first responders to retrieve automated external defibrillators (AED) for out-of-hospital cardiac arrests (OHCA). Objectives: This study aimed to assess the feasibility of integrating FD riders into the emergency medical service (EMS) system as OHCA responders. Methods: We enrolled OHCAs from the Taipei registry between 2017 and 2019. Using the Uber Eats website, a prominent FD service platform, we obtained data on FD hotspots to establish a reference point. Assumptions were made in our simulation to develop an integrated system where FD riders could participate in a crowdsourcing program. In the simulation, FD riders were assigned to respond to an OHCA within a 2-km distance by retrieving an AED or directly responding to the OHCA if bystander CPR was unavailable. We tested response rates from 10 to 100% and compared simulated AED arrival time with documented EMS response time in the registry. Results: During the study periods, 8,952 of 11,660 OHCA cases were accessible by FD riders. There were 418 restaurants clustered around 24 hotspots, and 2,050 AEDs were found within range of these restaurants (Image1). For FD-accessible OHCA cases, with simulating response rates ranging from 10 to 100%, the AED arrival time was reduced by 2.99 to 3.67 minutes. The effect was more pronounced during peak hour (Image 2). Conclusion: The results indicate that incorporating FD riders as OHCA responders into the EMS system is practical and beneficial in reducing the defibrillation waiting time for OHCA patients.

Substance use and pre-hospital crash injury severity among U.S. older adults: A five-year national cross-sectional study.

Alcohol and drug use (substance use) is a risk factor for crash involvement. To assess the association between substance use and crash injury severity among older adults and how the relationship differs by rurality/urbanicity. We pooled 2017-2021 cross-sectional data from the United States National Emergency Medical Service (EMS) Information System. We measured injury severity (low acuity, emergent, critical, and fatal) predicted by substance use, defined as self-reported or officer-reported alcohol and/or drug use. We controlled for age, sex, race/ethnicity, road user type, anatomical injured region, roadway crash, rurality/urbanicity, time of the day, and EMS response time. We performed a partial proportional ordinal logistic regression and reported the odds of worse injury outcomes (emergent, critical, and fatal injuries) compared to low acuity injuries, and the predicted probabilities by rurality/urbanicity. Our sample consisted of 252,790 older adults (65 years and older) road users. Approximately 67%, 25%, 6%, and 1% sustained low acuity, emergent, critical, and fatal injuries, respectively. Substance use was reported in approximately 3% of the population, and this proportion did not significantly differ by rurality/urbanicity. After controlling for patient, crash, and injury characteristics, substance use was associated with 36% increased odds of worse injury severity. Compared to urban areas, the predicted probabilities of emergent, critical, and fatal injuries were higher in rural and suburban areas. Substance use is associated with worse older adult crash injury severity and the injury severity is higher in rural and suburban areas compared to urban areas.

Improving EMS response times for out-of-hospital cardiac arrest in urban areas using drone-like vertical take-off and landing air ambulances: An international, simulation-based cohort study

BackgroundAdvances in vertical take-off and landing (VTOL) technologies may enable drone-like crewed air ambulances to rapidly respond to out-of-hospital cardiac arrest (OHCA) in urban areas. We estimated the impact of incorporating VTOL air ambulances on OHCA response intervals in two large urban centres in France and Canada. MethodsWe included adult OHCAs occurring between Jan. 2017–Dec. 2018 within Greater Paris in France and Metro Vancouver in Canada. Both regions utilize tiered OHCA response with basic (BLS)- and advanced life support (ALS)-capable units. We simulated incorporating 1–2 ALS-capable VTOL air ambulances dedicated to OHCA response in each study region, and computed time intervals from call reception by emergency medical services (EMS) to arrival of the: (1) first ALS unit (“call-to-ALS arrival interval”); and (2) first EMS unit (“call-to-first EMS arrival interval”). ResultsThere were 6,217 OHCAs included during the study period (3,760 in Greater Paris and 2,457 in Metro Vancouver). Historical median call-to-ALS arrival intervals were 21 min [IQR 16–29] in Greater Paris and 12 min [IQR 9–17] in Metro Vancouver, while median call-to-first EMS arrival intervals were 11 min [IQR 8–14] and 7 min [IQR 5–8] respectively. Incorporating 1–2 VTOL air ambulances improved median call-to-ALS arrival intervals to 7–9 min and call-to-first EMS arrival intervals to 6–8 min in both study regions (all P < 0.001). ConclusionVTOL air ambulances dedicated to OHCA response may improve EMS response intervals, with substantial improvements in ALS response metrics.

Effect of snow on the emergency medical service response times of out-of-hospital cardiac arrest in Japan, 2009-2019 (JCS-ReSS)

Effect of snow on the emergency medical service response times of out-of-hospital cardiac arrest in Japan, 2009-2019 (JCS-ReSS)

Incidence, process of care, and outcomes of out-of-hospital cardiac arrest in China: a prospective study of the BASIC-OHCA registry

Out-of-hospital cardiac arrest (OHCA) is an important global public health issue, but its epidemiology and outcomes in low-income and middle-income countries remain largely unknown. We aim to comprehensively describe the incidence, process of care, and outcomes of OHCA in China. In the prospective, multicentre, population-based Baseline Investigation of Out-of-hospital Cardiac Arrest (BASIC-OHCA) registry study, participating sites were selected from both urban and rural areas in all seven geographical regions across China. All patients with OHCA assessed by emergency medical service (EMS) staff were consecutively enrolled from Aug 1, 2019, to Dec 31, 2020. Patients with suspected cardiac arrest assessed by bystanders whose return of spontaneous circulation was achieved without the need for defibrillation or EMS personnel cardiopulmonary resuscitation were excluded. Patients with all key variables missing were excluded, including resuscitation attempt, age, sex, witnessed status, cause, all process of care indicators, and all outcome measures. In this analysis, we included data for EMS agencies serving 25 monitoring sites (20 urban and five rural) that included the entire serving population, data for the whole of 2020, and at least 50 OHCA patients in 2020. Data were collected and reported using the Utstein template. We calculated the crude incidence of EMS-assessed OHCA in 2020. We also report data on baseline characteristics (including sex, cause, location of OHCA, and presence of shockable rhythm), process of care (including EMS response time, cardiopulmonary resuscitation, defibrillation, and advanced life support), and outcomes of non-traumatic OHCA between Aug 1, 2019, and Dec 31, 2020, including survival and survival with favourable neurological outcomes at discharge or 30 days, and at 6 and 12 months. Of 115·1 million people served by the 25 participating sites, 132 262 EMS-assessed patients with OHCA were enrolled, and resuscitation was attempted for 42 054 (31·8%) patients between Aug 1, 2019, and Dec 31, 2020. The crude incidence of EMS-assessed OHCA was 95·7 per 100 000 population (95% CI 95·6-95·8) in 2020. Among 38 227 individuals with non-traumatic OHCA, 25 958 (67·9%) were male, 30 282 (79·2%) had a cardiac arrest at home, 32 523 (85·1%) had a presumed cardiac cause, and 2297 (6·0%) presented with an initial shockable rhythm. 4049 (11·5%) of 35 090 patients with an unwitnessed or bystander-witnessed OHCA received dispatcher-assisted cardiopulmonary resuscitation and 7121 (20·3%) received bystander cardiopulmonary resuscitation; only 14 (<0·1%) patients were assessed by bystanders with an automated external defibrillator. The median EMS response time was 12 min (IQR 9-16). At hospital discharge or 30 days, 441 (1·2%) of 38 227 survived, 304 (0·8%) survived up to 6 months, and 269 (0·7%) up to 12 months. At hospital discharge or 30 days, 309 (0·8%) survived with favourable neurological outcomes, 257 (0·7%) had favourable neurological outcomes at 6 months, and 236 (0·6%) at 12 months. Our findings revealed a high burden of EMS-assessed OHCA with a low proportion of resuscitation attempts. The suboptimal implementation of chain of survival and unsatisfactory prognosis call for national efforts to improve the care and outcomes of patients with OHCA in China. The National Science & Technology Fundamental Resources Investigation Program of China, the State Key Program of the National Natural Science Foundation of China, Taishan Pandeng Scholar Program of Shandong Province, the Key Research & Development Program of Shandong Province, the Interdisciplinary Young Researcher Groups Program of Shandong University, the Clinical Research Center of Shandong University, the ECCM Program of Clinical Research Center of Shandong University, and the Natural Science Foundation of Shandong Province.

Optimizing a Drone Network to Respond to Opioid Overdoses.

Introduction:Effective out-of-hospital administration of naloxone in opioid overdoses is dependent on timely arrival of naloxone. Delays in emergency medical services (EMS) response time could potentially be overcome with drones to deliver naloxone efficiently to the scene for bystander use. Our objective was to evaluate a mathematical optimization simulation for geographical placement of drone bases in reducing response time to opioid overdose. Methods: Using retrospective data from a single EMS system from January 2016-February 2019, we created a geospatial drone-network model based on current technological specifications and potential base locations. Genetic optimization was then used to maximize county coverage by drones and the number of overdoses covered per drone base. From this model, we identified base locations that minimize response time and the number of drone bases required. Results: In a drone network model with 2,327 opioid overdoses, as the number of modeled drone bases increased the calculated response time decreased. In a geospatially optimized drone network with four drone bases, response time compared to ambulance arrival was reduced by 4 minutes 38 seconds and covered 64.2% of the county. Conclusion: In our analysis we found that in a mathematical model for geospatial optimization, implementing four drone bases could reduce response time of 9-1-1 calls for opioid overdoses. Therefore, drones could theoretically improve time to naloxone delivery.