Ambulance Response Time Research Articles

Strategies to improve survival outcomes of out-of-hospital cardiac arrest (OHCA) given a fixed budget: A simulation study

BackgroundOur study aimed to identify a strategy that maximizes survival upon hospital discharge or 30-days post out-of-hospital cardiac arrest (OHCA) in Singapore for fixed investments of S$1, S$5, or S$10 million. Four strategies were compared: (1) no additional investment; (2) reducing response time via leasing of more ambulances; (3) increasing number of people trained in cardiopulmonary resuscitation (CPR); and (4) automated external defibrillators (AED). MethodsWe estimated the effect of ambulance response time, bystander CPR and AED on survival based on Singapore’s 2010–2015 OHCA registry data. We simulated the changes in ambulance response times and likelihood of (1) CPR and (2) AED usage as a function of their increased availability, which was then combined with the effect of each factor to determine the increase in survival for each strategy. ResultsSurvival given no additional investment was 4.03% (95% CI: 3.96%, 4.10%). The investments in ambulances, CPR training and AEDs for a given budget of S$1M changed survival to 4.03% (95% CI: 3.96%, 4.10%), 4.04% (95% CI: 3.98%, 4.11%), and 4.44% (95% CI: 4.35%, 4.54%), respectively. This generated 0, 2 and 102 additional life years saved respectively. Given a budget of S$5M or S$10M, 509 or 886 additional life years could be saved, by investing in an additional 10,000 or 20,000 AEDs respectively. The strategies reached a saturation effect whereby improvement in survival was marginal when the budget was increased to ≥S$5M for investment in ambulances and CPR training. ConclusionsInvesting in AEDs had the most gain in survival.

Effects of hourly precipitation and temperature on ambulance response time

BackgroundLonger ambulance response time (ART) delaying treatment would worsen conditions of seriously ill or injured patients, but limited evidence is available on the effects of weather factors on ART. This study aims to assess precipitation- and temperature-ART associations and their potential lagged effects using a novel modeling strategy. MethodsBased on 779,156 emergency records during 2010–2016 from the whole population in Shenzhen, China, we creatively combined quantile regression with distributed-lag nonlinear models to examine the non-linear and lagged effects of hourly precipitation and temperature on ART at the 50th and 90th percentiles. ResultsA linear precipitation-ART association with a delay of 9.01 (95%CI, 7.82–10.20) seconds at median ART for a 1 mm increase in hourly precipitation, and the effects lasted for 5 h with the greatest effect at the current hour. A two linear thresholds temperature-ART association revealed 1 °C decrease below 19 °C caused 1.68 (95%CI, 0.92–2.44) seconds delay in total ART over lag 0–7 h, and 1 °C increase above 24 °C caused 2.44 (95%CI, 1.55–3.33) seconds delay. The hourly call volumes exceeding 54 calls caused 8.79 (95%CI, 8.71–8.86) seconds delay in total ART for 1 more call, but not affected the effects of weather factors. The internal ART suffered more from the hourly call volumes, while the external ART suffered more from precipitation and temperature. The effects were apparently greater on ART at the 90th percentile than median. ConclusionsPrecipitation and temperature are independent risk factors for ambulance services performance, and their lagged effects are notable. The external ART and patients with long ART are vulnerable. More attention should be paid to weather and ART, and these findings may have implications for effective policies to reduce ART to protect public health.

162 Optimizing a Drone Network to Deliver Naloxone

Treatment of opioid overdoses depends on timely administration of naloxone. However, administration is delayed in some cases due to response time. Improvement in response time could be overcome with the use of drones. Drones have the potential to deliver naloxone efficiently to the scene of opioid overdose for bystander use. We hypothesize that using a mathematical model to optimize drone placement will reduce time to naloxone administration compared to ambulance response time. Using geocoded retrospective data from suspected opioid overdoses in Durham County, North Carolina from January 2016 to February 2019, we created a drone geospatial network model based on current technological specifications and potential base locations. All 29 fire, paramedic and EMS administrative buildings within Durham County were considered potential drone bases. The drone network modelled response time and county coverage. Then a genetic optimization model was built to maximize county coverage by drones and the number of overdoses covered per drone base. From this model, we quantified the optimum reduction in average response time balanced with the number drone bases required. From 2016 to early 2019, 2,327 distinct incidents of suspected opioid overdose data were found. The average time from 911 call to ambulance arrival at scene was 10 minutes 46 seconds. In the drone network model, as the response time decreased, the number of drone bases increased. In leveraging a balance between reductions in response time and number of drone bases required, we determined that the optimum number of drone bases would be four. Four drone bases would reduce response time by 4 minutes 38 seconds, covering 64.2% of the county (Fig. 1). Our analysis found that in a mathematical model for geospatial optimization, implementing four drone bases could reduce response time of 911 calls or opioid overdoses. Therefore, in theory, drones can improve time to naloxone delivery.

Predictors of Out of Hospital Cardiac Arrest Outcomes in Pre-Hospital Settings; a Retrospective Cross-sectional Study.

Different potential factors can affect the outcomes of Out of Hospital Cardiac Arrest (OHCA). The present study aimed to identify important factors contributing to the Return of Spontaneous Circulation(ROSC) and Survival to Hospital Discharge (SHD) in these patients. This cross-sectional study was conducted on all the OHCA patients who underwent Cardiopulmonary Resuscitation (CPR) in emergency medical service (EMS) of Hamedan province during 2016-2017. All the relevant data were retrieved from three sources, according to Utstein's style. In addition, univariate and multivariate logistic regressions were employed to identify predictive factors of ROSC and SHD using SPSS software, version 20. Among the 3214 eligible patients whose data were collected, most OHCA patients were female (59.7%) with the mean age of 58 years. Moreover,the majority of OHCAs (77.8%) occurred at home during 8pm-8am (65.1%) and about 26.3% of OHCAs were witnessed, with only 5.1% bystander-initiated CPR. Furthermore, the median ambulance response time and CPR duration were 6.0 and 20 minutes, respectively. Overall, ROSC and SHD success rates were 8.3 and 4.1%, respectively. Bystander CPR was found to be the most effective predicting factor for the success rate of ROSC (AOR=3.26, P<0.001) and SHD (AOR=3.04, P<0.001) after adjusting for the Utstein variables including the patients' age, gender, cardiac disease history, arrest time, CPR duration, response time, being witnessed, bystander CPR, and endotracheal intubation (ETI). The overall success rates of ROSC and SHD were 8.3% and 4.1%, respectively. The age, ambulance response time, CPR duration, and cardiac disease history were negatively associated with the outcomes of ROSC and SHD, while being witnessed, bystander CPR, ETI, and initial shockable rhythm were positively related to both of the above-mentioned outcomes.

The affordable care act and ambulance response times

This study contributes to the literature on the capacity challenges faced by health care providers after insurance expansions by examining the Affordable Care Act (ACA) and ambulance response times. Exploiting temporal and geographic variation in the implementation of the ACA as well as pre-treatment differences in uninsured rates, we estimate that the expansions of private and Medicaid coverage under the ACA combined to slow ambulance response times by an average of 24%. We conclude that, through extending coverage to individuals who, in its absence, would not have availed themselves of emergency medical services, the ACA added strain to emergency response systems.

The Use of Emergency Lights and Sirens by Ambulances and Their Effect on Patient Outcomes and Public Safety: A Comprehensive Review of the Literature - ADDENDUM.

The benefits of emergency lights and sirens (L&S) use as warning devices by ambulances continue to be a debated topic in Emergency Medical Services (EMS). While the most widely studied aspect of L&S use has been related to their effect on ambulance response and transport times, the literature suggests minimal time savings with more questionable impact on actual patient outcomes. As L&S use has been shown to increase the risk for vehicle crashes, the secondary concern of ambulance design and safety also becomes an important aspect on potential design recommendations that could mitigate the effects of a crash on patients, EMS providers, and the general public. The least studied aspect of L&S use (and probably the most important) is their effect on patient outcomes and quality of medical care during transport. The current evidence suggests no significant improvement on patient outcomes and potential worsening to certain aspects of patient care during transport. The purpose of this review was to examine the current literature regarding ambulance L&S use and the risks they pose to EMS providers, patients, and the general public. In doing so, it will provide sound background for EMS leaders to better develop policies governing the use of L&S by ambulances and promote better research in the patient outcomes effect associated with their use. This review offers some strategies in mitigating the risks associated with L&S use, such as ways to reduce their overall use and modifying other related factors to emergency medical vehicle collisions (EMVCs). Murray B , Kue R . The Use of Emergency Lights and Sirens by Ambulances and Their Effect on Patient Outcomes and Public Safety: A Comprehensive Review of the Literature . Prehosp Disaster Med . 2017 ; 32 ( 2 ): 209 – 216 .

Association between ambulance response time and neurologic outcome in patients with cardiac arrest

PurposeEmergency medical services (EMS) response time is one of prehospital factors associated with survival rate of patients with out-of-hospital cardiac arrest (OHCA). The objective of this study was to determine whether short EMS response time was associated with improved neurologic outcome of patients with OHCA through prospective analysis. MethodsWe performed a prospective observational analysis of collected data from KoCARC registry between October 2015 and December 2016. OHCA patients aged 18 years or older with presumed cardiac etiology by emergency physicians in emergency department were included in this study. ResultsOf 3187 cardiac arrest patients enrolled in the KoCARC registry, 2309 patients were included in the final analysis. Response time threshold was 11.5 min for prehospital return of spontaneous circulation and 7.5 min for survival to discharge and favorable neurologic outcome. Patients in the ≤7.5 min response time group showed increased odds of survival to discharge (OR: 1.54, 95% CI: 1.13–2.10, p = .006) and favorable neurologic recovery (OR: 2.01, 95% CI: 1.36–2.99, p = .001). When response time was decreased by 1 min, all outcomes were improved (survival to discharge, OR: 1.08; 95% CI: 1.04–1.12, p < .001; favorable neurological outcome, OR: 1.14, 95% CI: 1.07–1.21, p < .001). ConclusionWe found that shorter EMS response time could lead to favorable neurologic outcome in patients with OHCA of presumed cardiac origin. EMS response time threshold associated with improved favorable outcome was ≤7.5 min.

How is Ambulance Patient Care and Response Time Data Collected and Reported in Malaysia and Indonesia?

Introduction Ambulance service design is often reminiscent of the economic status of a country, with pre-hospital care in low to medium income countries relying on basic life support services and an historical ‘swoop and scoop’ Anglo-American emergency medical service model. The connection between pre-hospital intervention and patient outcome in low to medium income countries is unclear. This scoping study undertook an examination of the literature to establish the level and quality of patient care data collection, especially as it impacts ambulance case times in Malaysia and Indonesia. Methods A scoping review methodology with topic specific keywords including ‘ambulance’, ‘emergency medical service’, ‘pre-hospital’ (and their variants) using MEDLINE, CINAHL, Cochrane and EMBase databases was used. Results Of the 202 articles returned, 185 were screened, 85 full text articles were reviewed for relevance. Forty-three publications were included in the study with a number of other relevant from the grey literature. Conclusion The scoping study found there is no consistency in data collection methods in Indonesian or Malaysia, with some organisations collecting high quality data while others do not collect pre-hospital data. The study recommends deeper investigation into the status of standardisation of emergency medical services in the two countries and the manner in which the data is reported.

Prehospital response to respiratory distress by the public ambulance system in a Ukrainian city.

The capability of the public ambulance system in Ukraine to address urgent medical complaints in a prehospital environment is unknown. Evaluation using reliable sources of patient data is needed to provide insight into current treatments and outcomes. We obtained access to de-identified computer records from the emergency medical services (EMS) dispatch center in Poltava, a medium-sized city in central Ukraine. Covering a five-month period, we retrieved data for urgent calls with a patient complaint of respiratory distress. We evaluated ambulance response and treatment times, field diagnoses, and patient disposition, and analyzed factors related to fatal outcomes. Over the five-month period of the study, 2,029 urgent calls for respiratory distress were made to the Poltava EMS dispatch center. A physician-led ambulance typically responded within 10 minutes. Seventy-seven percent of patients were treated and released, twenty percent were taken to hospital, and three percent died in the prehospital phase. On univariate analysis, age over 60 and altered mental status at the time of the call were strongly associated with a fatal outcome. The EMS dispatch center in a medium-sized city in Ukraine has adequate organizational infrastructure to ensure that a physician-led public ambulance responds rapidly to complaints of respiratory distress. That EMS system was able to manage most patients without requiring hospital admission. However, a prehospital fatality rate of three percent suggests that further research is warranted to determine training, equipment, or procedural needs of the public ambulance system to manage urgent medical conditions.

A new model for standardising and treating thermal injury in the rat

Thermal burn injury methodologies are inconsistently described within the current literature. To permit the advancement of new treatments there is an urgent need for the development and standardisation of an acute rat model. We describe a rat thermal burn model that involves: anaesthesia, chronic catheterisation, skin preparation, baseline hemodynamic and physiological monitoring, and a quantifiable method to reproduce a severe full-thickness burns injury affecting ∼30% percent of the total body surface area (%TBSA). Following a 15 min post-burn period, treatment commences with an acute monitoring phase lasting up to 8 h, which can be modified according to individual protocols. This model reflects the clinical continuum-of-care from point-of-injury, a 15 min ambulance response time, a 60 min prehospital phase and hospital treatment monitoring phase. The model is validated with histological evidence of full-thickness injury, evidence of the hypermetabolic response (K+, Base Excess, lactate) and changes in complete blood counts.•It has been 50 years since Walker and Mason published their widely popular “A Standard Animal Burn Model”.•The model, however, lacks quantifiable methodology for the assessment of burn thickness, surface area burnt and physiological status.•We present a new standardised method for evaluation of drug and interventional therapies that mimic the clinical scenario including ambulance response, pre-hospital and hospital phases after burn.

Epidemiology of ambulance utilized patients in Addis Ababa, Ethiopia

BackgroundWell organized and appropriately utilized pre-hospital emergency services play a critical role in augmenting emergency care systems. The primary objective of this study was to understand the demographic and clinical profile of patients who used ambulances in Addis Ababa. The secondary objectives were to assess ambulance response time, transport time and reasons for referral amongst inter-facility transported patients in Addis Ababa.MethodsThe study was designed as a cross-sectional retrospective chart review of ambulance transported patients using ambulance station records from Addis Ababa Fire and Emergency Prevention and Control Authority. With IRB approval, simple random sampling and manual review of six months of clinical records was performed. Data were collected by trained data collectors and descriptive analysis was done using SPSS version 20.ResultsFemale patients used ambulance services more often than males (female to male ratio of 3:1) and the mean age of the patients was 26 years. The most commonly transported age group was 16–30 years, followed by 31–50 years and neonatal patients (i.e. < 1 month). The majority of the patients had pregnancy related illnesses (n = 492, 61.4%), followed by general medical issues (n = 210, 26.2%) and injury secondary to trauma (n = 99, 12.3%). Most patients (n = 702, 87.6%) were transported for inter-facility transfers, while only 12.4% (n = 99) were primary responses (i.e. from the scene). Prolonged labor was the most common reason (n = 103, 23.4%) for inter-facility transfer of pregnant patients, followed by premature rupture of the amniotic membrane (n = 60, 13.6%). The mean dispatch to scene time interval was 10.1 min, and mean scene to facility time interval was 17.2 min.ConclusionInter-facility transfers accounted for the largest proportion of ambulance utilization and dispatch in Addis Ababa. Ambulance transport time was twice as long compared to international recommendations of less than eight minutes for emergent transports. The most common reasons for ambulance dispatch were Obstetric. We recommend urgent action to decrease the transport times and to dedicate further pre-hospital resources to address the high burden of inter-facility transfers.

A US National Study of the Association Between Income and Ambulance Response Time in Cardiac Arrest

Emergency medical services (EMS) provide critical prehospital care, and disparities in response times to time-sensitive conditions, such as cardiac arrest, may contribute to disparities in patient outcomes. To investigate whether ambulance 9-1-1 times were longer in low-income vs high-income areas and to compare response times with national benchmarks of 4, 8, or 15 minutes across income quartiles. A retrospective cross-sectional study was performed of the 2014 National Emergency Medical Services Information System data in June 2017 using negative binomial and logistic regressions to examine the association between zip code-level income and EMS response times. The study used ambulance 9-1-1 response data for out-of-hospital cardiac arrest from 46 of 50 state repositories (92.0%) in the United States. The sample included 63 600 cardiac arrest encounters of patients who did not die on scene and were transported to the hospital. Four time measures were examined, including response time, on-scene time, transport time, and total EMS time. The study compared response times with EMS response time benchmarks for responding to cardiac arrest calls within 4, 8, and 15 minutes. The study sample included 63 600 cardiac arrest encounters of patients (mean [SD] age, 60.6 [19.0] years; 57.9% male), with 37 550 patients (59.0%) from high-income areas and 8192 patients (12.9%) from low-income areas. High-income areas had greater proportions of white patients (70.1% vs 62.2%), male patients (58.8% vs 54.1%), privately insured patients (29.4% vs 15.9%), and uninsured patients (15.3% vs 7.9%), while low-income areas had a greater proportion of Medicaid-insured patients (38.3% vs 15.8%). The mean (SD) total EMS time was 37.5 (13.6) minutes in the highest zip code income quartile and 43.0 (18.8) minutes in the lowest. After controlling for urban zip code, weekday, and time of day in regression analyses, total EMS time remained 10% longer (95% CI, 9%-11%; P < .001), translating to 3.8 minutes longer in the poorest zip codes. The EMS response time to patients in high-income zip codes was more likely to meet 8-minute and 15-minute cutoffs compared with low-income zip codes. Patients with cardiac arrest from the poorest neighborhoods had longer EMS times compared with those from the wealthiest, and response times were less likely to meet national benchmarks in low-income areas, which may lead to increased disparities in prehospital delivery of care over time.

Income and Ambulance Response Time Inequality

Income and Ambulance Response Time Inequality

Composite measures of healthcare quality: sensible in theory, problematic in practice

All healthcare systems show variation in the quality of care provided, whether that means access to primary care services,1 ambulance response times,2 Accident & Emergency waiting times3 or treatment processes...

What happened to my patient after I dropped them off at the ED? Linking Welsh ambulance to secondary care and mortality data

IntroductionThe Welsh ambulance service hold very detailed information about emergency calls received, incidents and associated ambulance journeys, but very little about what happens to patients after they have been conveyed to hospital.&#x0D; Linkage of ambulance data to secondary care and mortality data can allow new outcome measures to be developed.&#x0D; Objectives and ApproachA proof of concept was jointly initiated by the Welsh Ambulance Service, Welsh Government and the NHS Wales Informatics in order to explore how ambulance conveyance data could be linked to other routinely collected secondary care and mortality data, with the aim of developing new outcome-based measures for the evaluation of the effectiveness of the ambulance service and the unscheduled care system as a whole.&#x0D; As there were very few patient demographic data items common to both the ambulance and secondary care datasets, the resulting probabilistic linkage relied largely on the use of time and location-based distributions.&#x0D; ResultsThe linkage methodology proved to be highly successful for those patients conveyed by ambulance to an ED, with the various location and time-based fields from the ambulance dataset combining well with similar fields in the ED dataset. Out of all ED attendance records which had "Ambulance" as the stated mode of arrival, an associated ambulance record was found in over 90\% of cases.&#x0D; Additional exact and rules-based deterministic methods were used to link the ED attendances to associated admissions, critical care and mortality records, with new ED, in-hospital and longer term outcome variables developed.&#x0D; Finally, the project team analysed the impact of ambulance response times and ED handover delays on these outcome measures.&#x0D; Conclusion/ImplicationsThe work demonstrated how the linked data could provide managers, commisioners and policy-makers with a more holistic view of the unscheduled care system. Work to-date has focussed mainly on conveyances to ED, however the next stage will be to develop outcome measures relating to those patients treated at the scene or advised by phone.

The Effect of Ambulance Response Time on Survival Following Out-of-Hospital Cardiac Arrest.

Out of hospital cardiac arrest (OHCA) is one of the more common causes of death in Germany. Ambulance response time is an important planning parameter for emergency medical services (EMS) systems. We studied the effect of ambulance response time on survival after resuscitation from OHCA. We analyzed data from the German Resuscitation Registry for the years 2010-2016. First, we used a multivariate logistic regression analysis to determine the effect of ambulance response time (defined as the interval from the alarm to the arrival of the first rescue vehicle) on the hospital-discharge rate (in percent), depending on various factors, including resuscitation by bystanders. Second, we compared faster and slower EMS systems (defined as those arriving on the scene within 8 minutes in more than 75% of cases or in ≤ 75% of cases) with respect to the frequency of resuscitation and the number of surviving patients. Our analysis of data from a total of 10 853 patients in the logistical regression model revealed that the rate of hospital discharge was significantly affected by the ambulance response time, bystander resuscitation, past medical history, age, witnessed vs. unwitnessed collapse, the initial heart rhythm, and the site of the collapse. The success of resuscitation was inversely related to the ambulance response time; thus, among patients who did not receive bystander resuscitation, the discharge rate declined from 12.9% at a mean response time of 1 minute and 10 seconds to 6.4% at a mean response time of 9 minutes and 47 seconds. Twelve faster EMS systems and 13 slower ones were identified, with a total of 9669 and 7865 resuscitated patients, respectively. The faster EMS systems initiated resuscitation more frequently and also had a higher discharge rate with good neurological outcome in proportion to the population of the catchment area (7.7 versus 5.6 persons per 100 000 population per year, odds ratio [OR] 0.72, 95% confidence interval [0.66; 0.79], p<0.001). Rapid ambulance response is associated with a higher rate of survival from OHCA with good neurological outcome. The response time, independently of whether bystander resuscitation measures are provided, ha^ a significant independent effect on the survival rate. In drawing conclusions from these findings, one should bear in mind that this was a retrospective registry study, with the corresponding limitations.

A Lean transportation approach for improving emergency medical operations

This paper extends the approach of Lean transportation to improve the performance of emergency medical processes (EMP) by adapting its main concepts into the main characteristics of the EMP environment. The paper is based on an inductive theory-building process initiated from a case study in the field of emergency medical services. The development of the suggested performance improvement approach triggered from an exhaustive analysis of a process involved and an exploratory review of the existing improvement approaches available. The process of concern can be described as a specialized transportation process, where human lives are at risk. Its characteristics led to a natural application of Lean transportation. The results include, a novel approach for improving the agility and efficient EMS processes. This is validated with an application for improving ambulance response times and turnaround times of the Red Cross operations located in Monterrey, Mexico. The approach proved to be an integrated scheme for identifying waste opportunities at a systems level. This characteristic is important to let operations management prioritize improvement efforts in a limited budget situation. This work suggests the application of the emerging Lean transportation approach for increasing the agility performance of EMS processes.

LiDAR—A Technology to Assist with Smart Cities and Climate Change Resilience: A Case Study in an Urban Metropolis

In this paper, we demonstrate three unique use cases of LiDAR data and processing, which can be implemented in an urban metropolis to determine the challenges that are associated with climate change. LiDAR data for the City of Toronto were collected in April 2015 with a density of 10 points/m2. We utilized both a digital terrain model and a bare earth digital elevation model in this work. The first case study estimated storm water, in which we compared flow accumulation values and catchment areas generated with a 20-m DEM and a 1-m LiDAR DEM. The finer resolution DEM demonstrated that the urban street features play a significant role in flow accumulation by directing flows. Urban catchment areas were found to occur on spatial scales that were smaller than the 20-m DEM cell size. For the second case study, the solar potential in the City of Toronto was calculated based on the slope and aspect of each land parcel. According to area, 56% of the city was found to have high solar potential, with 33% and 11% having medium and low solar potential. For the third case study, we calculated the building heights for 16,715 high-rise buildings in Toronto, which were combined with ambulance and fire emergency response times required to reach the base of the building. All buildings that had more than 17 stories were within a 5-min response time for both fire and ambulance services. Only 79% and 88% of these buildings were within a 3-min response time for ambulance and fire emergencies, respectively. LiDAR data provides a highly detailed record of the built urban environment and can provide support in the planning and assessment of climate change resilience activities.

Pre-hospital ambulance care of patients following a suspected seizure: A cross sectional study

PurposeWe aimed to investigate the characteristics of patients presenting to the ambulance service with suspected seizures, the costs of managing these patients and the factors which predicted transport to hospital. MethodsWe employed a cross-sectional design using routine clinical data from a UK regional ambulance service. Logistic regression was used to identify predictors of transport to hospital from ambulance response times, demographics, clinical (physiological) findings and treatments. ResultsThere were 177,715 emergency incidents recorded in 2011/12 of which 2.9% (5139/177,715) were classified as seizures by ambulance call handlers and 2.7% (4884/177,715) by paramedics on the scene. Suspected seizures were the seventh most common call type. The annual cost of managing these incidents was £890,148. Clinical and physiological variables were normal for most patients. 59.3% (2894/4884) of patients were transported to hospital. 1/4884 (0.02%) patient died. Administration of diazepam, insertion of an airway and pyrexia perfectly predicted transport to hospital, tachycardia had a modest association, but other variables were only weak predictors of transport to hospital. ConclusionsThis study shows that most patients after a suspected seizure are not acutely unwell but nevertheless most patients are transported to hospital. Further research is required to determine which factors are important in decisions to transport to hospital and to create evidence-based tools to help paramedics identify patients who could be safely managed without transport to hospital.

Neighborhood Poverty and 9-1-1 Ambulance Response Time

Background: Are 9-1-1 ambulances relatively late to poorer neighborhoods? Studies suggesting so often rely on weak measures of neighborhood (e.g., postal zip code), limit the analysis to particular ambulance encounters (e.g., cardiac arrest responses), and do little to account for variations in dispatch priority or intervention severity. Methods: We merged EMS ambulance contact records in a single California county (n = 87,554) with tract-level data from the American Community Survey (n = 300). After calculating tract-level median ambulance response time (MART), we used ordinary least squares (OLS) regression to estimate a conditional average relationship between neighborhood poverty and MART and quantile regression to condition this relationship on 25th, 50th, and 75th percentiles of MART. We also specified each of these outcomes by five dispatch priorities and by three intervention severities. For each model, we estimated the associated changes in MART per 10 percentage point increase in tract-level poverty while adjusting for emergency department proximity, population density, and population size. Results: Our study produced three major findings. First, most of our tests suggested tract-level poverty was negatively associated with MART. Our baseline OLS model estimates that a 10 percentage point increase in tract-level poverty is associated with almost a 24 s decrease in MART (−23.55 s, 95% confidence interval [CI] −33.13 to −13.98). Results from our quantile regression models provided further evidence for this association. Second, we did not find evidence that ambulances are relatively late to poorer neighborhoods when specifying MART by dispatch priority. Third, we were also unable to identify a positive association between tract-level poverty and MART when we specified our outcomes by three intervention severities. Across each of our 36 models, tract-level poverty was either not significantly associated with MART or was negatively associated with MART by a magnitude smaller than a full minute per estimated 10 percentage point increase in poverty concentration. Conclusion: Our study challenges the commonly held assumption that ambulances are later to poor neighborhoods. We scrutinize our findings before cautiously considering their relevance for ambulance response time research and for ongoing conversations on the relationship between neighborhood poverty and prehospital care.