Emergency Medical Services Response Time Research Articles

356EMF Coagulation Abnormalities Resulting from Cardiac Arrest

Cessation of cardiac output during out-of-hospital cardiac arrest (OHCA) results in microvascular thrombosis that contributes to protracted hypo-perfusion and damage to vital organs. We seek to examine the association of ischemic clot burden following return of spontaneous circulation (ROSC) with post-arrest organ dysfunction and functional outcome. We screened consecutive adult, non-traumatic, OHCA patients with ROSC on arrival to emergency department (ED) and eligible for targeted temperature management (TTM) from July 1, 2016 to present. Those subjects with DNR order, pre-existing neurocognitive impairment, coagulopathy, following commands, or whose treatment included systemic heparin or fibriniolysis were excluded. Structured data were collected in the Utstein style including demographic variables, EMS response times, pre-morbid conditions, intra-arrest conditions (initial cardiac rhythm, low/no-flow time, etc), post-arrest care including TTM, neurological assessments, laboratory values, assessments of organ injury, survival, and functional status. Blood (20cc) was collected at five clinically relevant intervals: ED arrival, at 33°C (∼4hrs), rewarming (∼28hrs), normothermia (∼44hrs), and ICU day 3. Samples were processed for PT/PTT/INR, lactate, d-dimer, thromboelatography (TEG), platelet impedance aggregometry, activated protein C (aPC), Factors V, VIII, Xa, plasminogen activator inhibitor 1 (PAI-1), fibrinogen, Thrombin-antithrombin complex (TAT), Syndecan-1, and Heparan Sulfate. The time-dependent nature of aPC, TEG, and platelet aggregometry required IRB approval of a unique 24-hour delayed consent from a legally authorized representative (LAR). We screened 28 patients of which 10 were eligible, 2 refused, and 2 no LAR could be identified. Characteristics of six patients enrolled were median age 45.5 years (IQR 37-60), 50% African-American, 66% male. 66% witnessed arrest, 66% shockable initial rhythm, 83% received bystander CPR, median ischemic time 35m (IQR 15-60), median initial d-dimer 8954 ng/mL (IQR 2710-18548), median initial lactate 8.0 mMol/L (IQR 3.2-11.4), median initial TEG measure of clot formation (K) 0.9 (0.9-1.2). All subjects died prior to discharge with 4 completing entire protocol. Planned multivariate analysis is impossible due to small sample size; however, in interim analysis d-dimer correlates with ischemic insult (R2=0.6563; figure). Interim analysis suggests that intra- and post-arrest microvascular thrombosis, as measured by d-dimer, shows promise as a surrogate for ischemic insult. Agents to temper or reverse this thrombotic state could represent a novel therapeutic target to improve illness severity and favorable functional survival.

EMS Response Times Are Double in Rural vs. Urban Areas

To define the difference in rural versus urban emergency medical services (EMS) response times, investigators reviewed records from 485 EMS agencies in

P4934Impact of emergency medical services response time on benefits of bystander-initiated cardiopulmonary resuscitation in patients with out-of-hospital cardiac arrest

P4934Impact of emergency medical services response time on benefits of bystander-initiated cardiopulmonary resuscitation in patients with out-of-hospital cardiac arrest

Emergency Medical Services Response Times in Rural, Suburban, and Urban Areas

This study describes the interval between receipt of a 911 call and the arrival of the first emergency medical service unit on the scene of a reported emergency in the United States.

Direct Transport to a Percutaneous Cardiac Intervention Center and Outcomes in Patients With Out-of-Hospital Cardiac Arrest.

Practice guidelines recommend regional systems of care for out-of-hospital cardiac arrest. However, whether emergency medical services should bypass nonpercutaneous cardiac intervention (non-PCI) facilities and transport out-of-hospital cardiac arrest patients directly to PCI centers despite longer transport time remains unknown. Using the Cardiac Arrest Registry to Enhance Survival with geocoding of arrest location, we identified out-of-hospital cardiac arrest patients with prehospital return of spontaneous circulation and evaluated the association between direct transport to a PCI center and outcomes in North Carolina during 2012 to 2014. Destination hospital was classified according to PCI center status (catheterization laboratory immediately accessible 24/7). Inverse probability-weighted logistic regression accounting for age, sex, emergency medical services response time, clustering of county, transport time to nearest PCI center, initial heart rhythm, and prehospital ECG information was performed. Of 1507 patients with prehospital return of spontaneous circulation, 1359 (90.2%) were transported to PCI centers, of whom 873 (57.9%) bypassed the nearest non-PCI hospital and 148 (9.8%) were transported to non-PCI hospitals. Discharge survival was higher among those transported to PCI centers (33.5% versus 14.6%; adjusted odds ratio, 2.47; 95% confidence interval, 2.08-2.92). Compared with patients taken to non-PCI hospitals, odds of survival were higher for patients taken to the nearest hospital with PCI center status (odds ratio, 3.07; 95% confidence interval, 1.90-4.97) and for patients bypassing closer hospitals to PCI centers (odds ratio, 3.02; 95% confidence interval, 2.01-4.53). Adjusted survival remained significantly better across transport times of 1 to 5, 6 to 10, 11 to 20, 21 to 30, and >30 minutes. Direct transport to a PCI center is associated with better outcomes for out-of-hospital cardiac arrest patients, even when bypassing nearest hospital and regardless of transport time.

A System-Based Intervention to Improve Access to Hyperacute Stroke Care.

Hyperacute stroke is a time-sensitive emergency for which outcomes improve with faster treatment. When stroke systems are accessed via emergency medical services (EMS), patients are routed to hyperacute stroke centres and are treated faster. But over a third of patients with strokes do not come to the hospital by EMS, and may inadvertently arrive at centres that do not provide acute stroke services. We developed and studied the impact of protocols to quickly identify and move "walk-in" patients from non-hyperacute hospitals to regional stroke centres (RSCs). Protocols were developed by a multi-disciplinary and multi-institutional working group and implemented across 14 acute hospital sites within the Greater Toronto Area in December of 2012. Key metrics were recorded 18 months pre- and post-implementation. The teams regularly reviewed incident reports of protocol non-adherence and patient flow data. Transports increased by 80% from 103 to 185. The number of patients receiving tissue plasminogen activator (tPA) increased by 68% from 34 to 57. Total EMS transport time decreased 17 minutes (mean time of 54.46 to 37.86 minutes, p<0.0001). Calls responded to within 9 minutes increased from 34 to 59%. A systems-based approach that included a multi-organizational collaboration and consensus-based protocols to move patients from non-hyperacute hospitals to RSCs resulted in more patients receiving hyperacute stroke interventions and improvements in EMS response and transport times. As hyperacute stroke care becomes more centralized and endovascular therapy becomes more broadly implemented, the protocols developed here can be employed by other regions organizing patient flow across systems of stroke care.

LO08: Effect of an intact “chain of survival” sequence on survival to discharge from out-of-hospital cardiac arrest

Introduction: The “chain of survival” is a 5-link theoretical construct that has been central to cardiac arrest resuscitation for over 40 years. Although the role of each link has been extensively studied, little is known about the impact of performing the chain of survival in sequence. The purpose of this study was to estimate the proportion of out-of-hospital cardiac arrest (OHCA) responses by Emergency Medical Services (EMS) that had an intact chain of survival sequence response, and the effect of this on survival to hospital discharge. Methods: We conducted a prospective cohort study of adult (&amp;gt;age 20 years) OHCA patients using data collected between 2005-2007 by the Resuscitation Outcomes Consortium (ROC). ROC is a research network involving 10 research sites and 264 EMS agencies across North America. Using routinely collected data, we coded cases as receiving an intact or non-intact chain of survival sequence based on EMS cardio pulmonary resuscitation (CPR), rhythm analysis or defibrillation, epinephrine administration or endotracheal intubation, and transport to a hospital with an electrophysiology lab or percutaneous coronary intervention capability, contingent on the patient’s condition when EMS arrived. Multiple variable logistic regression was performed, adjusting for known (Utstein) survival predictors, to estimate the independent effect of intact chain of survival sequence on survival to hospital discharge. REB approval was obtained. Results: We enrolled12,821 OHCA cases, of which, 29.4% (n=3,773) had an intact chain of survival and 7.6% (n=972) survived to hospital discharge. Cases with an intact chain of survival were younger, and more likely to arrest in public, receive bystander CPR, occur in the USA and specific ROC sites, and had faster EMS response times. The adjusted odds ratio of survival to hospital discharge with an intact chain of survival sequence was 2.4 (95% CI: 2.1-2.8). A sensitivity analysis of 4,056 cases with known timing of endotracheal intubation found a similar adjusted odds ratio of 2.1 (95% CI: 1.6-2.8). Conclusion: Our results indicate that OCHA resuscitation with an intact chain of survival occurs in approximately 1/3 of cases, and results in over a two-fold increase in the odds of surviving to hospital discharge. Initiatives to improve EMS teamwork and increase the proportion of OHCA resuscitation with an intact chain of survival appear to be warranted.

Out-of-hospital cardiac arrest survival in drug-related versus cardiac causes in Ontario: A retrospective cohort study

BackgroundDrug overdose causes approximately 183,000 deaths worldwide annually and 50,000 deaths in Canada and the United States combined. Drug-related deaths are concentrated among young people, leading to a substantial burden of disease and loss of potential life years. Understanding the epidemiology, patterns of care, and prognosis of drug-related prehospital emergencies may lead to improved outcomes.MethodsWe conducted a retrospective cohort study of out-of-hospital cardiac arrests with drug-related and presumed cardiac causes between 2007 and 2013 using the Toronto Regional RescuNet Epistry database. The primary outcome was survival to hospital discharge. We computed standardized case fatality rates, and odds ratios of survival to hospital discharge for cardiac arrests with drug-related versus presumed cardiac causes, adjusting for confounders using logistic regression.ResultsThe analysis involved 21,497 cardiac arrests, including 378 (1.8%) drug-related and 21,119 (98.2%) presumed cardiac. Compared with the presumed cardiac group, drug-related arrest patients were younger and less likely to receive bystander resuscitation, have initial shockable cardiac rhythms, or be transported to hospital. There were no significant differences in emergency medical service response times, return of spontaneous circulation, or survival to discharge. Standardized case fatality rates confirmed that these effects were not due to age or sex differences. Adjusting for known predictors of survival, drug-related cardiac arrest was associated with increased odds of survival to hospital discharge (OR1.44, 95%CI 1.15–1.81).InterpretationIn out-of-hospital cardiac arrest, patients with drug-related causes are less likely than those with presumed cardiac causes to receive bystander resuscitation or have an initial shockable rhythm, but are more likely to survive after accounting for predictors of survival. The demographics and outcomes among drug-related cardiac arrest patients offers unique opportunities for prehospital intervention.

Improvements in Out-of-Hospital Cardiac Arrest Survival from 1998 to 2013

Objectives: Out-of-hospital cardiac arrest (OHCA) remains a major public health burden. Aggregate OHCA survival to hospital discharge has reportedly remained unchanged at 7.6% for almost 30 years from 1970 to 2008. We examined the trends in adult OHCA survival over a 16-year period from 1998 to 2013 within a single EMS agency. Methods: Observational cohort study of adult OHCA patients treated by Tualatin Valley Fire & Rescue (TVF&R) from 1998 to 2013. This is an ALS first response fire agency that maintains an active Utstein style cardiac arrest registry and serves a population of approximately 450,000 in 9 incorporated cities in Oregon. Primary outcomes were survival to hospital discharge in all patients and in the subgroup with witnessed ventricular fibrillation/pulseless ventricular tachycardia (VF/VT). The impact of key covariates on survival was assessed using univariate logistic regression. These included patient factors (age and sex), event factors (location of arrest, witnessed status, and first recorded cardiac arrest rhythm), and EMS system factors (response time interval, bystander CPR, and non-EMS AED shock). We used multivariate logistic regression to examine the impact of year increment on survival after multiple imputation for missing data. Sensitivity analysis was performed with complete cases. Results: During the study period, 2,528 adult OHCA had attempted field resuscitation. The survival rate for treated cases increased from 6.7% to 18.2%, with witnessed VF/VT cases increasing from 14.3% to 31.4% from 1998 to 2013. Univariate analysis showed that younger age, male sex, public location of arrest, bystander or EMS witnessed event, initial rhythm of pulseless electrical activity (PEA) or VF/VT, bystander CPR, non-EMS AED shock, and a shorter EMS response time were independently associated with survival. After adjustment for covariates, the odds of survival increased by 9% (OR 1.09, 95%CI: 1.05–1.12) per year in all treated cases, and by 6% (OR 1.06, 95% 1.01–1.10) per year in witnessed VF/VT subgroups. Findings remained consistent on sensitivity analysis. Conclusions: Overall survival from treated OHCA has increased over the last 16 years in this community. These survival increases demonstrate that OHCA is a treatable condition that warrants further investigation and investment of resources.

Features of hospital and emergency medical service in out-of-hospital cardiac arrest patients with shockable rhythm

ObjectivePredicting the outcome of out-of-hospital cardiac arrest (OHCA) patients is crucial. We examined hospital characteristics and parameters of emergency medical service (including scene time interval and direct ambulance delivery to intensive heart hospitals) as survival or outcome predictors. Study designData from 546 consecutive OHCA shockable patients treated between January 2012 and December 2015 in Taoyuan City (Taiwan, ROC) were collected. In addition to demographic data, location of arrest, initial rhythm, availability of a hospital with or without 24/7 percutaneous coronary intervention (PCI), emergency medical service (EMS) time, provision of cardiopulmonary resuscitation by a bystander, presence of a witness at collapse, and level of life support were analysed. ResultsMultivariate analysis showed that hospitalisation with immediate PCI availability was an independent predictor (OR: 4.32; 95% CI: 1.27–14.70) solely for the outcome of survival until discharge. The presence of a witness while collapsing (OR: 3.52; 95% CI: 1.03–11.98), EMS response time (OR: 0.83; 95% CI: 0.70–0.98), and scene time interval (STI; OR: 0.89; 95% CI: 0.81–0.99) were valuable for predicting the neurological outcome. ConclusionsDirect ambulance delivery to intensive heart hospitals that had 24/7 PCI availability was associated with a higher probability of surviving until discharge in OHCA patients with shockable rhythms. Similarly, a witnessed collapse was correlated with being discharged alive from hospital and recovering with good cerebral performance. In addition, longer response time and scene time interval indicated poorer survival and neurological outcome.

Evaluating the Potential Benefits of Advanced Automatic Crash Notification.

Advanced Automatic Collision Notification (AACN) services in passenger vehicles capture crash data during collisions that could be transferred to Emergency Medical Services (EMS) providers. This study explored how EMS response times and other crash factors impacted the odds of fatality. The goal was to determine if information transmitted by AACN could help decrease mortality by allowing EMS providers to be better prepared upon arrival at the scene of a collision. The Crash Injury Research and Engineering Network (CIREN) database of the US Department of Transportation/National Highway Traffic Safety Administration (USDOT/NHTSA; Washington DC, USA) was searched for all fatal crashes between 1996 and 2012. The CIREN database also was searched for illustrative cases. The NHTSA's Fatal Analysis Reporting System (FARS) and National Automotive Sampling System Crashworthiness Data System (NASS CDS) databases were queried for all fatal crashes between 2000 and 2011 that involved a passenger vehicle. Detailed EMS time data were divided into prehospital time segments and analyzed descriptively as well as via multiple logistic regression models. The CIREN data showed that longer times from the collision to notification of EMS providers were associated with more frequent invasive interventions within the first three hours of hospital admission and more transfers from a regional hospital to a trauma center. The NASS CDS and FARS data showed that rural collisions with crash-notification times >30 minutes were more likely to be fatal than collisions with similar crash-notification times occurring in urban environments. The majority of a patient's prehospital time occurred between the arrival of EMS providers on-scene and arrival at a hospital. The need for extrication increased the on-scene time segment as well as total prehospital time. An AACN may help decrease mortality following a motor vehicle collision (MVC) by alerting EMS providers earlier and helping them discern when specialized equipment will be necessary in order to quickly extricate patients from the collision site and facilitate expeditious transfer to an appropriate hospital or trauma center. Plevin RE , Kaufman R , Fraade-Blanar L , Bulger EM . Evaluating the potential benefits of advanced automatic crash notification. Prehosp Disaster Med. 2017;32(2):156-164.

Emergency Medical Services Utilization in EMS Priority Conditions in Beirut, Lebanon.

Early activation and use of Emergency Medical Services (EMS) are associated with improved patient outcomes in EMS priority conditions in developed EMS systems. This study describes patterns of EMS use and identifies predictors of EMS utilization in EMS priority conditions in Lebanon METHODS: This was a cross-sectional study of a random sample of adult patients presenting to the emergency department (ED) of a tertiary care center in Beirut with the following EMS priority conditions: chest pain, major trauma, respiratory distress, cardiac arrest, respiratory arrest, and airway obstruction. Patient/proxy survey (20 questions) and chart review were completed. The responses to survey questions were "disagree," "neutral," or "agree" and were scored as one, two, or three with three corresponding to higher likelihood of EMS use. A total scale score ranging from 20 to 60 was created and transformed from 0% to 100%. Data were analyzed based on mode of presentation (EMS vs other). Among the 481 patients enrolled, only 112 (23.3%) used EMS. Mean age for study population was 63.7 years (SD=18.8 years) with 56.5% males. Mean clinical severity score (Emergency Severity Index [ESI]) was 2.5 (SD=0.7) and mean pain score was 3.1 (SD=3.5) at ED presentation. Over one-half (58.8%) needed admission to hospital with 21.8% to an intensive care unit care level and with a mortality rate of 7.3%. Significant associations were found between EMS use and the following variables: severity of illness, degree of pain, familiarity with EMS activation, previous EMS use, perceived EMS benefit, availability of EMS services, trust in EMS response times and treatment, advice from family, and unavailability of immediate private mode of transport (P≤.05). Functional screening, or requiring full assistance (OR=4.77; 95% CI, 1.85-12.29); acute symptoms onset ≤ one hour (OR=2.14; 95% CI, 1.08-4.26); and higher scale scores (OR=2.99; 95% CI, 2.20-4.07) were significant predictors of EMS use. Patients with lower clinical severity (OR=0.53; 95% CI, 0.35-0.81) and those with chest pain (OR=0.05; 95% CI, 0.02-0.12) or respiratory distress (OR=0.15; 95% CI, 0.07-0.31) using cardiac arrest as a reference were less likely to use EMS. Emergency Medical Services use in EMS priority conditions in Lebanon is low. Several predictors of EMS use were identified. Emergency Medical Services initiatives addressing underutilization should result from this proposed assessment of the perspective of the EMS system's end user. El Sayed M , Tamim H , Al-Hajj Chehadeh A , Kazzi AA . Emergency Medical Services utilization in EMS priority conditions in Beirut, Lebanon. Prehosp Disaster Med. 2016;31(6):621-627.

Continuous Quality Improvement Efforts Increase Survival with Favorable Neurologic Outcome after Out-of-hospital Cardiac Arrest

Objective: To assess system-wide implementation of specific therapies focused on perfusion during cardiopulmonary resuscitation (CPR) and cerebral recovery after Return of Spontaneous Circulation (ROSC). Methods: Before and after retrospective analysis of an out-of-hospital cardiac arrest database. Implementation trial in the urban/suburban community of Alameda County, California, USA, population 1.6 million, from November 2009–December 2012. Adult patients with non-traumatic out-of-hospital cardiac arrest (OHCA) who received CPR and/or defibrillation. The impedance threshold device was used throughout this study and there was an increased use of mechanical CPR (mCPR) and in-hospital therapeutic hypothermia (HTH). Results: Rates of ROSC, survival to hospital discharge and Cerebral Performance Category (CPC) scores were compared using univariate and multivariable analyses. A total of 2,926 adult non-traumatic patients with OHCA received CPR during the study period. From 2009–2011 to 2012, there was an increase in ROSC from 29.0% to 34.4% (p = 0.003) and a non-significant increase in hospital discharge from 10.2% to 12.0% (p = 0.16). There was a 76% relative increase in survival with favorable neurologic function between the two periods, as determined by CPC ≤ 2, from 4.5% to 7.9% (unadjusted OR = 1.80; CI = 1.31, 2.48; p < 0.001). After adjusting for witnessed arrest, bystander CPR, initial rhythm (VT/VF vs. others), placement of an advanced airway, EMS response time, drugs administered, and age, the OR was 1.61 (1.10, 2.36; p = 0.015). Using a stepwise multivariable logistic regression model, the independent predictors of CPC ≤ 2 were 2012 (vs. 2009–2011; p = 0.022), witnessed arrest (p < 0.001), initial rhythm VT/VF (p < 0.001), and advanced airway (inverse association p < 0.001). Additional analyses of the three prescribed therapies, separately and in combination, demonstrated that for those patients admitted to the hospital, mCPR with HTH had the biggest impact on survival to hospital discharge with CPC ≤ 2. Conclusions: Specific therapies within a system of care (mCPR, HTH), developed to enhance circulation during CPR and cerebral recovery after ROSC, significantly improved survival by 74% with favorable neurologic function following OHCA.

Factors Influencing the Timeliness of Emergency Medical Service Response to Time Critical Emergencies

Objective: While emergency medical service (EMS) response times (ERT) remain a leading measure of system performance in many developed countries, relatively few studies have explored the factors associated with meeting benchmark performance for potentially time critical incidents. The purpose of this study was to identify system-level and patient-level factors associated with ERT, which are readily available at the time of ambulance dispatch. Methods: Between July 2009 and June 2014, we included data from 1,000,458 EMS responses to time critical “lights and sirens” incidents in Melbourne, Australia. The primary outcome measure was ERT, defined as the time from emergency call to the arrival of the first EMS team on scene. Quantile regression models were used to identify system-level and patient-level factors associated with 10-percentile intervals of ERT. Results: The median ERT was 10.6 minutes (IQR: 8.1–14.0), increasing from 9.6 minutes (IQR: 7.6–12.5) in 2009/10 to 11.0 minutes (IQR: 8.4–14.7) in 2013/14 (p < 0.001). System-level factors independently associated with the 90th percentile ERT were distance to scene, activation time, turnout time, case upgrade, hour of day, day of week, workload in the previous hour, ambulance skill set, priority zero case (e.g., suspected cardiac or respiratory arrest), and average hospital delay time in the previous hour. Patient-level factors such as age, gender, chief medical complaint, and severity of complaint were also significantly associated with ERT. Conclusions: System-level and patient-level factors available at the time of ambulance dispatch are useful predictors of ERT performance, which could be used to improve the timeliness of EMS response.

Ethnic differences in sudden cardiac arrest resuscitation

ObjectiveEthnic differences in sudden cardiac arrest resuscitation have not been fully explored and studies have yielded inconsistent results. We examined the association of ethnicity with factors affecting sudden cardiac arrest...

Contemporary Prehospital Emergency Medical Services Response Times for Suspected Stroke in the United States

Background and Purpose: There are no contemporary national-level data on Emergency Medical Services (EMS) response times for suspected stroke in the United States (US). Because effective stroke treatment is time-dependent, we characterized response times for suspected stroke, and examined whether they met guideline recommendations. Methods: Using the National EMS Information System dataset, we included 911 calls for patients ≥ 18 years with an EMS provider impression of stroke. We examined variation in the total EMS response time by dispatch notification of stroke, age, sex, race, region, time of day, day of the week, as well as the proportion of EMS responses that met guideline recommended response times. Total EMS response time included call center dispatch time (receipt of call by dispatch to EMS being notified), EMS dispatch time (dispatch informing EMS to EMS starts moving), time to scene (EMS starts moving to EMS arrival on scene), time on scene (EMS arrival on scene to EMS leaving scene), and transport time (EMS leaving scene to reaching treatment facility). Results: We identified 184,179 events with primary impressions of stroke (mean age 70.4 ± 16.4 years, 55% male). Median total EMS response time was 36 (IQR 28.7–48.0) minutes. Longer response times were observed for patients aged 65–74 years, of white race, females, and from non-urban areas. Dispatch identification of stroke versus “other” was associated with marginally faster response times (36.0 versus 36.7 minutes, p < 0.01). When compared to recommended guidelines, 78% of EMS responses met dispatch delay of <1 minute, 72% met time to scene of <8 minutes, and 46% met on-scene time of <15 minutes. Conclusions: In the United States, time from receipt of 9-1-1 calls to treatment center arrival takes a median of 36 minutes for stroke patients, an improvement upon previously published times. The fact that 22%–46% of EMS responses did not meet stroke guidelines highlights an opportunity for improvement. Future studies should examine EMS diagnostic accuracy nationally or regionally using outcomes based approaches, as accurate recognition of prehospital strokes is vital in order to improve response times, adhere to guidelines, and ultimately provide timely and effective stroke treatment.

Locating AED Enabled Medical Drones to Enhance Cardiac Arrest Response Times

Background: Out-of-hospital cardiac arrest (OOHCA) is prevalent in the United States. Each year between 180,000 and 400,000 people die due to cardiac arrest. The automated external defibrillator (AED) has greatly enhanced survival rates for OOHCA. However, one of the important components of successful cardiac arrest treatment is emergency medical services (EMS) response time (i.e., the time from EMS “wheels rolling” until arrival at the OOHCA scene). Unmanned Aerial Vehicles (UAV) have regularly been used for remote sensing and aerial imagery collection, but there are new opportunities to use drones for medical emergencies. Objective: The purpose of this study is to develop a geographic approach to the placement of a network of medical drones, equipped with an automated external defibrillator, designed to minimize travel time to victims of out-of-hospital cardiac arrest. Our goal was to have one drone on scene within one minute for at least 90% of demand for AED shock therapy, while minimizing implementation costs. Methods: In our study, the current estimated travel times were evaluated in Salt Lake County using geographical information systems (GIS) and compared to the estimated travel times of a network of AED enabled medical drones. We employed a location model, the Maximum Coverage Location Problem (MCLP), to determine the best configuration of drones to increase service coverage within one minute. Results: We found that, using traditional vehicles, only 4.3% of the demand can be reached (travel time) within one minute utilizing current EMS agency locations, while 96.4% of demand can be reached within five minutes using current EMS vehicles and facility locations. Analyses show that using existing EMS stations to launch drones resulted in 80.1% of cardiac arrest demand being reached within one minute Allowing new sites to launch drones resulted in 90.3% of demand being reached within one minute. Finally, using existing EMS and new sites resulted in 90.3% of demand being reached while greatly reducing estimated overall costs. Conclusion: Although there are still many factors to consider, drone networks show potential to greatly reduce life-saving equipment travel times for victims of cardiac arrest.

Abstract WMP70: Accuracy of Emergency Dispatcher Stroke Recognition When Employing a Stroke Screening Tool: A Systematic Review

Introduction: Emergency dispatchers are usually the first contact point for stroke patients accessing the healthcare system. Dispatcher stroke recognition is associated with better paramedic stroke recognition and faster emergency medical services (EMS) response time, but stroke is often unrecognized during the initial call. We conducted a systematic review to quantify the accuracy of emergency dispatcher stroke recognition when employing stroke screening tools. Methods: We conducted a comprehensive search Medline, EMBASE, CINAHL, and Cochrane databases to identify studies of dispatcher stroke recognition accuracy using a stroke screening tools such as the Medical Priority Dispatch System (MDPS) or Face Arm Speech Time (FAST) mnemonic. Studies were included if they reported dispatcher sensitivity or positive predictive value (PVP) using hospital stroke/TIA diagnosis as the gold standard. Study quality was assessed using QUADAS 2. Two independent reviewers determined study eligibility, assessed quality, and abstracted data. Results: We identified 1450 abstracts; seven cohort studies met inclusion criteria. Stroke screening tools included MPDS (n=4), FAST (n=2), and a novel screening algorithm (n=1). The sensitivity of dispatcher stroke recognition (5 studies, range 41-83%) and PPV (7 studies, range 42% -68%) were variable. Specificity was high (3 studies, 95-99%). No screening tool demonstrated superiority. Included studies had moderate risk of bias and dramatically variable stroke prevalence (range 3-68%). Conclusion: Published reports of screening tools utilized by emergency dispatchers demonstrate suboptimal sensitivity and PPV. More research is needed to identify the causes of poor dispatcher stroke recognition and to improve stroke screening tools.

Ex-Urban Sprawl as a Factor in Traffic Fatalities and EMS Response Times in the Southeastern United States

Only recently have researchers been documenting the problems of traffic fatalities when it comes to uneven development patterns, or “sprawl”. Also, other than cases studies at the local level, no research has examined the variations in emergency services response to traffic accidents and other medical crises due to urban or ex-urban built-environment patterns (i.e., compact versus sprawled development). This research note validates earlier findings of a connection between some type of sprawled development and traffic fatalities (Ewing, Schieber, and Zegeer, 2003 and Lucy, 2003) and also shows a link between emergency services response variations due to settlement patterns in the metropolitan counties of states that make up the southeastern United States. Settlement patterns and the degree of urbanization and ex-urbanization seem to make a difference with regard to traffic fatalities and EMS run times.

Improved Survival With Favorable Neurological Outcome in Elderly Individuals With Out-of-Hospital Cardiac Arrest in Japan - A Nationwide Observational Cohort Study.

There is sparse data regarding the survival and neurological outcome of elderly patients with out-of-hospital cardiac arrest (OHCA). OHCA patients (334,730) aged ≥75 years were analyzed using a nationwide, prospective, population-based Japanese OHCA database from 2008 to 2012. The overall 1-month survival with favorable neurological outcome (Cerebral Performance Category Scale, category 1 or 2; CPC 1-2) rate was 0.88%. During the study period, the annual 1-month CPC 1-2 rate in whole OHCA significantly improved (0.73% to 0.96%, P for trend <0.001). In particular, outcomes of OHCA patients aged 75 to 84 years and those aged 85 to 94 years significantly improved (0.98% to 1.28%, P for trend=0.01; 0.46% to 0.70%, P for trend <0.001, respectively). However, in OHCA patients aged ≥95 years, the outcomes did not improve. Multivariate logistic regression analysis indicated that younger age, shockable first documented rhythm, witnessed arrest, earlier emergency medical service (EMS) response time, and cardiac etiology were significantly associated with the 1-month CPC 1-2. Under these conditions, elderly OHCA patients who had cardiac etiology, shockable rhythm and had a witnessed arrest had acceptable 1-month CPC1-2 rate; 7.98% in cases where OHCA was witnessed by family, 15.2% by non-family, and 25.6% by EMS. The annual 1-month CPC 1-2 rate after OHCA among elderly patients significantly improved, and the resuscitation of elderly patients in a selected population is not futile. (Circ J 2016; 80: 1153-1162).