Patient-specific predictors of ambulance use

Association between social support and ambulance use among older people in Japan: an empirical cross-sectional study

BACKGROUND

Ambulance service demand and utilization are increasing worldwide. To address this issue, the factors that affect ambulance use must be identified. Few studies have examined factors that can intervene and thus reduce the frequency of ambulance use. This study aimed to examine the association between social support and ambulance use among older adults in Japan. We hypothesize that social support is associated with reduced ambulance use.

METHODS

This cross-sectional study was conducted as part of the Japan Gerontological Evaluation Study. In December 2019 and January 2020, we collaborated with individuals aged 65 years or above with no long-term care needs. A total of 24,581 participants were included in the analysis. The objective and explanatory variables were ambulance use and social support, respectively. Binomial regression analysis was used to calculate the odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

Social support was associated with ambulance use. People who had no one to listen to their complaints or worries were significantly more likely to use ambulance services than those who did (OR [95% CI] = 1.26 [1.03-1.53]). People with no one to take care of them when they were ill were also significantly more likely to use ambulance services than those who had someone to provide care (1.15 [1.01-1.31]). Moreover, the results of binomial logistic regression analysis indicated that individuals who called an ambulance but were not hospitalized had significantly lower social support compared to those who did not call an ambulance.

CONCLUSIONS

The results suggest that the presence and quality of social support play a significant role in ambulance use among older adults in Japan. Our findings can help policymakers to plan and implement strategies for reducing the burden on emergency medical care.

Predictors, Prevalence, and Clinical Outcomes of Out-of-Hospital Cardiac Arrests in Croatia: A Nationwide Study

BACKGROUND

Out-of-hospital cardiac arrest (OHCA) remains a pivotal health challenge globally. In Croatia, there has been a knowledge gap regarding the prevalence, predictors, and outcomes of OHCA patients. This study aims to determine the prevalence, prediction, and outcomes of OHCA patients in Croatia.

METHODS

An extensive one-year analysis was performed on all OHCA treated by the Emergency Medical Service in Croatia, based on the Utstein recommendations. Data were extracted from Croatian Institute of Emergency Medicine databases, focusing on adult individuals who experienced sudden cardiac arrest in out-of-hospital settings in Croatia.

RESULTS

From 7773 OHCA cases, 9.5% achieved spontaneous circulation pre-hospital. Optimal outcomes corresponded to EMS intervention within ≤13 min post-arrest onset AUC = 0.577 (95% CI: 0.56-0.59; p < 0.001) and female gender OR = 1.81 (95% CI: 1.49-2.19; p < 0.001). Northern Croatia witnessed lower success rates relative to the capital city Zagreb OR = 0.68 (95% CI: 0.50-0.93; p = 0.015).

CONCLUSIONS

Early intervention by EMS, specifically within a 13-min period following the onset of a cardiac arrest, significantly enhances the probability of achieving successful OHCA outcomes. Gender differences and specific initial heart rhythms further influenced the likelihood of successful outcomes. Regional disparities, with reduced success rates in northern Croatia compared to the City of Zagreb, were evident.

Factors Associated with Willingness to Call Emergency Medical Services for Worsening Symptoms of COVID-19 in Addis Ababa, Ethiopia

Background

In response to the COVID-19 pandemic, the Ethiopian Ministry of Health has established ambulances and dispatch centers specifically designed to transport COVID-19 patients to city medical centers. Due to a lack of evidence in this area, it is critical to assess the factors that influence the willingness to call for emergency medical services.

Methods

A community-based cross-sectional study was conducted from June to July 2021 in Addis Ababa. The data were gathered through use of a pretested questionnaire and analyzed using SPSS 25. Logistic regression was used to calculate odds ratios with and without confounding variable controls, and significant associations were declared at (0.05). For the variables that show significant associations in bivariate and multivariate analyses, a 95% confidence interval is provided.

Results

Three-quarters of those surveyed said they would call ambulance if they experienced worsening COVID-19 symptoms. The individual’s language was associated with the willingness to call EMS for worsening COVID-19 symptoms [AOR 0.51(95% CI: 0.28–0.92)].; awareness of the availability of toll-free ambulance services [AOR 3.4(95% CI: 1.92–5.95)]; recalling an EMS number [AOR 4.3(95% CI: 1.71–10.67)]; ambulance crew quality of care perception [AOR 3.6(95% CI: 2.09–6.10)]; ambulance service adequacy and accessibility perception [AOR 0.25(95% CI: 0.11–0.55)].

Conclusion

The study showed significant portion of the Addis Ababa community recognized the need to call EMS due to worsening COVID-19 symptoms. The individual’s language, awareness of toll-free ambulance; ability to recall an ambulance number, perception of the ambulance crew’s quality of care and adequacy and accessibility of service in the city influence the decision to call an ambulance. The finding highlights the significance of addressing problems through various media outlet, for advocacy and public awareness. More research, including qualitative studies, is needed to investigate the factors that encourage people to seek EMS.

Emergency Medical Services Demand: An Analysis of County-Level Social Determinants

OBJECTIVES

Variations in the demand for Emergency Medical Services (EMS) exist when observed at a local level. This unspecified heterogeneity leads to an investigation of social factors contributing to EMS demand.

METHODS

Data for this study were collected from publicly available EMS reports from Florida and Oklahoma for 2009 - 2015. Health and social data were gathered from County health rankings and roadmap reports. Data were combined into a single dataset, and pooled ordinary-least-squares models with time-fixed effects were utilized for tests of inference. EMS call volume was log-transformed to derive a semi-elasticity function.

RESULTS

A total of 874 county-year observations were analyzed. Increases in poor/fair health (95% CI: 0.6% - 3.9%), binge drinking (95% CI: 1.6% - 3.5%), teen birth rate (95% CI: 1.1% - 5.2%), unemployment rate (95% CI: 0.5% - 3.9%), and violent crime rate (95% CI: 1.0% - 3.0%) were associated with an increase in the EMS demand rate.

CONCLUSION

The data supports the notion that some community measures have an effect on EMS demand as counties with higher levels of poor health, binge drinking, teen births, unemployment, and violent crime saw higher EMS demand. These factors may have been treated as spurious, or overlooked by policy makers and EMS leadership.

What factors are associated with ambulance use for non-emergency problems in children? A systematic mapping review and qualitative synthesis

OBJECTIVE

To explore what factors are associated with ambulance use for non-emergency problems in children.

METHODS

This study is a systematic mapping review and qualitative synthesis of published journal articles and grey literature. Searches were conducted on the following databases, for articles published between January 1980 and July 2020: MEDLINE, EMBASE, PsycINFO, CINAHL and AMED. A Google Scholar and a Web of Science search were undertaken to identify reports or proceedings not indexed in the above. Book chapters and theses were searched via the OpenSigle, EThOS and DART databases. A literature advisory group, including experts in the field, were contacted for relevant grey literature and unpublished reports. The inclusion criteria incorporated articles published in the English language reporting findings for the reasons behind why there are so many calls to the ambulance service for non-urgent problems in children. Data extraction was divided into two stages: extraction of data to generate a broad systematic literature 'map', and extraction of data from highly relevant papers using qualitative methods to undertake a focused qualitative synthesis. An initial table of themes associated with reasons for non-emergency calls to the ambulance for children formed the 'thematic map' element. The uniting feature running through all of the identified themes was the determination of 'inappropriateness' or 'appropriateness' of an ambulance call out, which was then adopted as the concept of focus for our qualitative synthesis.

RESULTS

There were 27 articles used in the systematic mapping review and 17 in the qualitative synthesis stage of the review. Four themes were developed in the systematic mapping stage: socioeconomic status/geographical location, practical reasons, fear of consequences and parental education. Three analytical themes were developed in the qualitative synthesis stage including practicalities and logistics of obtaining care, arbitrary scoring system and retrospection.

CONCLUSIONS

There is a lack of public and caregiver understanding about the use of ambulances for paediatrics. There are factors that appear specific to choosing ambulance care for children that are not so prominent in adults (fever, reassurance, fear of consequences). Future areas for attention to decrease ambulance activation for paediatric low-acuity reports were highlighted as: identifying strategies for helping caregivers to mitigate perceived risk, increasing availability of primary care, targeted education to particular geographical areas, education to first-time parents with infants and providing alternate means of transportation.

PROSPERO REGISTRATION NUMBER

CRD42019160395.

Predicting hospitalization of pediatric asthma patients in emergency departments using machine learning

MOTIVATION

The timely identification of patients for hospitalization in emergency departments (EDs) can facilitate efficient use of hospital resources. Machine learning can help the early prediction of ED disposition; however, application of machine learning models requires both computer science skills and domain knowledge. This presents a barrier for those who want to apply machine learning to real-world settings.

OBJECTIVES

The objective of this study was to construct a competitive predictive model with a minimal amount of human effort to facilitate decisions regarding hospitalization of patients.

METHODS

This study used the electronic health record data from five EDs in a single healthcare system, including an academic urban children's hospital ED, from January 2009 to December 2013. We constructed two machine learning models by using automated machine learning algorithm (autoML) which allows non-experts to use machine learning model: one with data only available at ED triage, the other adding information available one hour into the ED visit. Random forest and logistic regression were employed as bench-marking models. The ratio of the training dataset to the test dataset was 8:2, and the area under the receiver operating characteristic curve (AUC), accuracy, and F1 were calculated to assess the quality of the models.

RESULTS

Of the 9,069 ED visits analyzed, the study population was made up of males (62.7 %), median (IQR) age was 6 (4, 10) years, and public insurance coverage (66.0 %). The majority had an Emergency Severity Index score of 3 (52.9 %). The prevalence of hospitalization was 22.5 %. The AUCs were 0.914 and 0.942. AUCs were 0.831 and 0.886 for random forests, and 0.795 and 0.823 for logistic regression. Among the predictors, an outcome at a prior visit, ESI level, time to first medication, and time to triage were the most important features for the prediction of the need for hospitalization.

CONCLUSIONS

In comparison with the conventional approaches, the use of autoML improved the predictive ability for the need for hospitalization. The findings can optimize ED management, hospital-level resource utilization and improve quality. Furthermore, this approach can support the design of a more effective patient ED flow for pediatric asthma care.

Factors Associated With First Medication Time for Children Treated in the Emergency Department for Asthma

OBJECTIVES

Acute asthma exacerbations are among the most common reasons for childhood emergency department (ED) visits and hospitalizations. Although early ED administration of asthma medication has been shown to decrease hospitalizations, studies of factors associated with early ED asthma medication delivery have been limited. The objective of our study was to identify patient- and ED-related factors associated with early medication delivery among children treated in the ED for asthma exacerbations.

METHODS

This retrospective study used electronic health record data from all encounters for a primary diagnosis of asthma in an academic children's hospital ED during the study period 2009 to 2013. Using multivariate logistic regression, we identified the association between patient- and ED-related factors and the time to first medication defined as a binary outcome using a threshold of 1 hour from ED arrival. We then stratified our analysis by triage level (Emergency Severity Index [ESI]).

RESULTS

Of the 4846 encounters during the study period, 62% were male, mean age was 7.30 years, 76% had public insurance, and 57% had an ESI level of 3. Medication was administered within 1 hour of arrival in 2236 encounters (46%). After adjusting for covariates, multivariate logistic regression revealed that patients were less likely to have medications within 1 hour when they had less severe ESI (ESI 2 vs ESI 4: odds ratio [OR], 0.139; confidence interval [CI], 0.114-0.170), arrived via non-emergency medical services (OR, 0.525; CI, 0.413-0.665), or arrived to a crowded ED (OR, 0.574; CI, 0.505-0.652). Age, sex, and insurance type were not associated with timeliness of initial medication administration. Stratified analyses demonstrated that the crowding effect was larger for less severely ill patients.

CONCLUSIONS

Our study found that patient severity (acuity level, arrival mode) and level of ED crowing-but not demographic factors-are associated with the administration of medication in the first hour to pediatric patients with asthma. Our findings may be helpful in redesigning asthma care management strategies.

Predictors Affecting the Elderly's Use of Emergency Medical Services

Objectives

Elderly adults are the demographic most likely to utilize emergency medical services (EMS). This study aimed to examine the difference in EMS utilization in subgroups of the elderly population by assessing the predictors for using EMS.

Methods

Using both descriptive and logistic regression analyses, this study analyses data from the 2014 Korean Health Panel Survey (n = 3,175).

Results

It was observed that certain predisposing factors such as age, sex, and marital status were significant predictors of EMS utilization. However, differences in EMS need do not fully account for the original differences observed between subgroups of elderly Koreans. While health status and disability were important predictors of elderly Koreans using EMS, place of residence did not account for subgroup differences. Nonetheless, place of residence remained particularly important predictors of EMS utilization for the elderly.

Conclusion

Emergency needs and resource availability are 2 main determinants for elderly Koreans using EMS. In addition, it was observed that the demographic subgroup profile of unmarried/divorced/separated/widowed men who were aged 75 and older was least likely to utilize EMS. Improving their resource availability to meet their EMS needs should be a top priority for national policy making to narrow elderly population subgroup differences.

Sub-Daily Exposure to Fine Particulate Matter and Ambulance Dispatches during Wildfire Seasons: A Case-Crossover Study in British Columbia, Canada

BACKGROUND

Exposure to fine particulate matter (PM2.5) during wildfire seasons has been associated with adverse health outcomes. Previous studies have focused on daily exposure, but PM2.5 levels in smoke events can vary considerably within 1 d.

OBJECTIVES

We aimed to assess the immediate and lagged relationship between sub-daily exposure to PM2.5 and acute health outcomes during wildfire seasons in British Columbia.

METHODS

We used a time-stratified case-crossover study design to evaluate the association between modeled hourly PM2.5 and ambulance dispatches during wildfire seasons from 2010 to 2015. Distributed lag nonlinear models were used to estimate the lag-specific and cumulative odds ratios (ORs) at lags from 1 to 48 h. We examined the relationship for all dispatches and dispatches related to respiratory, circulatory, and diabetic conditions, identified by codes for ambulance dispatch (AD), paramedic assessment (PA) or hospital diagnosis (HD).

RESULTS

Increased respiratory health outcomes were observed within 1 h of exposure to a 10-μg/m3 increase in PM2.5. The 48-h cumulative OR [95% confidence interval (CI)] was 1.038 (1.009, 1.067) for the AD code Breathing Problems and 1.098 (1.013, 1.189) for PA code Asthma/COPD. The point estimates were elevated within 1 h for the PA code for Myocardial Infarction and HD codes for Ischemic Heart Disease, which had 24-h cumulative ORs of 1.104 (0.915, 1.331) and 1.069 (0.983, 1.162), respectively. The odds of Diabetic AD and PA codes increased over time to a cumulative 24-h OR of 1.075 (1.001, 1.153) and 1.104 (1.015, 1.202) respectively.

CONCLUSIONS

We found increased PM2.5 during wildfire seasons was associated with some respiratory and cardiovascular outcomes within 1 h following exposure, and its association with diabetic outcomes increased over time. Cumulative effects were consistent with those reported elsewhere in the literature. These results warrant further investigation and may have implications for the appropriate time scale of public health actions. https://doi.org/10.1289/EHP5792.

Sociodemographic Characteristics Associated with Contacts to Emergency Medical Services and Out-of-Hours Primary Care: An Observational Study of 2.3 Million Citizens

Background

Out-of-hours (OOH) health care services are often divided into emergency medical services (EMS) and OOH primary care (OOH-PC). EMS and many OOH-PC use telephone triage, yet the patient still makes the initial choice of contacting a service and which service. Sociodemographic characteristics are associated with help-seeking. Yet, differences in characteristics for EMS and OOH-PC patients have not been investigated in any large-scale cohort studies. Such knowledge may contribute to organizing OOH services to match patient needs. Thus, in this study we aimed to explore which sociodemographic patient characteristics were associated with utilizing OOH health care and to explore which sociodemographic characteristics were associated with EMS or OOH-PC contact.

Methods

A population-based observational cohort study of inhabitants in two regions (North Denmark Region and Capital Region of Copenhagen) with or without contact to OOH services during 2016 was conducted. Associations between sociodemographic characteristics and OOH contacts (and EMS versus OOH-PC contact) were evaluated by regression analyses.

Results

We identified 619,857 patients with OOH contact. Female sex (IRR=1.16 (95% CI: 1.16-1.17)), non-western ethnicity (IRR=1.02 (95% CI: 1.01-1.02)), living alone (IRR=1.08 (95% CI: 1.08-1.09)), age groups ≥81 years (IRR=2.00 (95% CI: 1.98-2.02)) and 0-18 years (IRR=1.66 (95% CI: 1.66-1.67)) and low income (IRR=1.41 (95% CI: 1.40-1.42)) were more likely to contact OOH health care compared to males, Danish ethnicity, citizens cohabitating, age 31-65 years and high income. Disability pensioners more often contacted OOH care (IRR=1.79 (95% CI: 1.77-1.81) compared to employees. Old age (≥81 years) (OR=3.21 (95% CI: 3.13-3.30)), receiving cash benefits (OR=2.45 (95% CI: 2.36-2.54)), low income (OR=1.76 (95% CI: 1.72-1.81)) and living alone (OR=1.40 (95% CI: 1.37-1.42)) were all associated with EMS contacts rather than OOH-PC contacts.

Conclusion

Several sociodemographic factors were associated with contacting a health care service outside office hours and with contacting EMS rather than OOH-PC. Old age, low income, low education and low socioeconomic status were of greatest importance.

Ambulance Transport of Patients with Mild Conditions in Hokkaido, Japan

Understanding the epidemiological distributions of ambulance transport for patients with mild conditions according to age, disease, and geographic region could help in achieving optimal use of ambulance services. In the present study, we explored the descriptive epidemiology of ambulance transports in Hokkaido, the northernmost prefecture of Japan, identifying potential factors that determine the frequency of transports for mild diseases. Of the total 153,667 ambulance transports in Hokkaido during 2016, we found that two-thirds were for older people, of which about 60% resulted in hospital admission. There were 74,485 transports for mild cases, which were most commonly for psychiatric disorders among working-age adults (n = 4805), heart diseases among older people (n = 4246), and sensory organ diseases among older people (n = 3589). Examining the ecological correlations over 58 geographic units of ambulance services, the total unemployment rate and distance to the nearest tertiary care hospital were, respectively, positively and negatively correlated with the standardized transport ratio for multiple mild diseases. The proportion of working-age adults was uniquely identified as a possible positive predictor in mild cases of psychiatric disorders. As the identified potential predictors could be helpful in considering countermeasures, the causal links should be examined in future studies.

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.

Diagnostic accuracy of physician-staffed emergency medical teams: a retrospective observational cohort study of prehospital versus hospital diagnosis in a 10-year interval

Background

In Germany, emergency medical teams are staffed with physicians but evidence regarding their prehospital diagnostic accuracy remains poor.

Objective

To evaluate the out-of-hospital diagnostic accuracy of physician-staffed emergency medical teams (PEMTs).

Methods

A retrospective observational cohort study involving the Emergency Medical Service Bonn, Germany, from January to December 2004 and 2014 respectively. A total of 8346 patients underwent medical treatment by PEMTs, of which 1960 adult patients (inclusion criteria: ≥18 years of age, hospital diagnosis available) were included for further analysis. Reasons for non-inclusion: death on scene, outpatient, interhospital transfer, mental illness, false alarm, no hospital medical history available. The overall diagnostic accuracy (correct or false) of PEMTs was measured after matching the prehospital diagnosis with the corresponding diagnosis of the hospital. Secondary outcome measures were incidence of common PEMT diagnoses (acute coronary syndrome (ACS), dyspnea, stroke/intracerebral bleeding), recognition rate of a given disease by PEMTs, and prehospital diagnostic accuracy in elderly patients.

Results

PEMT calls increased 2-fold over a decade (2004: n = 3151 vs. 2014: n = 5195). Overall diagnostic accuracy of PEMTs increased from 87.5% in 2004 to 92.6% in the year 2014. The incidence of common PEMT diagnoses such as ACS, dyspnea or stroke/intracerebral bleeding increased 2-fold from 2004 to 2014. The recognition rate of a given disease by the PEMT varied between 2004 and 2014: an increase was observed when a stroke/intracerebral bleeding was diagnosed (2004: 67% vs. 2014: 83%; p = 0.054), a decreased rate of recognition occurred when a syncope/collapse was diagnosed (2004: 81% vs. 2014: 56%; p = 0.007) and a sepsis appears to be a rare event for EMS personnel (2004: 0% vs. 2014: 23%). Linear regression analysis revealed that the prehospital diagnostic accuracy decreases in the elderly patient.

Conclusions

The overall prehospital diagnostic accuracy of PEMTs improved between the year 2004 and 2014 respectively. Our findings suggest that the incidence of common diseases (ACS, dyspnea stroke/intracerebral bleeding, sepsis) increased over a 10-year period. Diagnostic accuracy of different diseases varied but generally decreased in the elderly patient. Regular training of EMS personnel and public campaigns should be implemented to improve the diagnostic accuracy in the future.

Electronic supplementary material

The online version of this article (10.1186/s13049-019-0617-3) contains supplementary material, which is available to authorized users.

Use of pre-hospital emergency medical services in urban and rural municipalities over a 10 year period: an observational study based on routinely collected dispatch data

BACKGROUND

Pre-hospital emergency medical services (EMS) are an integral part of emergency medical care. EMS planning can be achieved by analyzing patterns of use. However, long-term time trends of EMS use have rarely been studied. The objective of this retrospective study was to investigate utilization patterns over a ten year period, and to compare utilization trends between urban and rural municipalities and between events with and without prehospital emergency physician (PEP) dispatch.

METHODS

Routine data collected by 26 dispatch centers in the federal state of Bavaria, Germany, from 2007 to 2016 was analyzed. Emergency locations were classified into five levels of rurality. Negative binomial mixed effects regression models were fitted to predict emergency rates and to investigate differences in rates and utilization trends. Graphical representation methods were used to compare distribution of transport rates and distribution across daytime and weekday.

RESULTS

Twelve million two hundred thousand one hundred fifty-five dispatches assigned to 7,725,636 single emergencies were included. The mean number of emergencies per year and 1000 population (emergency rate) was 42.8 (±16.0) in rural municipalities and 80.7 (±9.3) in large cities. Compared to rural municipalities, cities had higher emergency rates without (IRR = 3.0, CI 2.2-4.0) and with pre-hospital physicians (IRR = 1.5, CI 1.2-2.0). Between 2007 and 2016, the absolute number of emergencies increased by 49.1%. Estimated annual percent change of emergency rates without physician activation ranged from 5.7% (CI 4.3-7.1) in cities to 7.8% (CI 7.6-7.9) in rural areas. Changes in emergency rates with physician attendance were lower, with estimated increases between 1.3 and 2.4%. The average proportion of patients transported to a hospital was lower in cities and remained unchanged. There were no considerable differences or changes in the distribution across daytime and weekdays.

CONCLUSION

Differences between cities and other areas suggest that the planning of EMS should be targeted to regional characteristics. A substantial increase in emergency rates was observed across all areas of Bavaria, but did not impact transport rates or temporal distributions. Further research is needed to better understand the urgency of emergency events and reasons behind increasing EMS utilization.

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

IMPORTANCE

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.

OBJECTIVES

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.

DESIGN, SETTING, AND PARTICIPANTS

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.

MAIN OUTCOMES AND MEASURES

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.

RESULTS

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.

CONCLUSIONS AND RELEVANCE

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.

Exploring the Predictors of Emergency Department Triage Acuity Assignment in Patients With Sepsis

Background and purpose

Evidence suggests that septic patients, who require prompt medical attention, may be undertriaged, resulting in delayed treatment. The purpose of this study was to examine patient and contextual variables that contribute to high- versus low-acuity triage classification of patients with sepsis.

Methods

Data were abstracted from the medical records of 154 adult patients with sepsis admitted to hospital through a Canadian Emergency Department. Logistic regression was used to explore the predictors of triage classification.

Results

Language barriers or chronic cognitive impairment (odds ratio 5.7; 95% confidence interval 2.15, 15.01), acute confusion (odds ratio 3.4; confidence interval 1.3, 8.2), unwell appearance (odds ratio 3.4; 95% confidence interval 1.7, 7.0), and hypotension (odds ratio 0.98; confidence interval 0.96, 1.0) were predictive of higher acuity classification. Temperature, heart rate, respiratory rate, and contextual factors were not related to triage classification.

Conclusions

Several patient-related factors were related to triage classification. However, the finding that temperature and heart and respiratory rates were not related to triage classification was troubling. Our findings point to a need for enhanced education for triage nurses regarding the physiological indices of sepsis. The sensitivity of the Canadian Triage Assessment Scale, used in Canadian Emergency Rooms, also needs to be examined.

Acute stroke alert activation, emergency service use, and reperfusion therapy in Sweden

OBJECTIVES

Ambulance services and stroke alerts reduce the time from stroke onset to acute stroke diagnosis. We describe the use of stroke alerts and ambulance services in different hospitals and patient groups and their relationship with reperfusion therapy.

METHODS

This nationwide study included 49,907 patients admitted with acute stroke who were registered in The Swedish Stroke Register (Riksstroke) in 2011-2012.

RESULTS

The proportions of patients admitted as stroke alerts out of all acute stroke admissions varied from 12.2% to 45.7% in university hospitals (n = 9), 0.5% to 38.7% in specialized nonuniversity hospitals (n = 22), and 4.2% to 40.3% in community hospitals (n = 41). Younger age, atrial fibrillation (AF), living in an institution, reduced consciousness upon admission, and hemorrhagic stroke were factors associated with a higher probability of stroke alerts. Living alone, primary school education, non-European origin, previous stroke, diabetes, smoking, and dependency in activities of daily living (ADL) were associated with a lower probability of stroke alert. The proportion of patients arriving at the hospital by ambulance varied from 60.3% to 94.5%. Older age, living alone, primary school education, being born in a European country, previous stroke, AF, dependency in ADL, living in an institution, reduced consciousness upon admission, and hemorrhagic stroke were associated with ambulance services. Hospital stroke alert frequencies correlated strongly with reperfusion rates (r = .75).

CONCLUSION

Acute stroke alerts have a significant potential to improve stroke reperfusion rates. Prehospital stroke management varies conspicuously between hospitals and patient groups, and the elderly and patients living alone have a markedly reduced likelihood of stroke alerts.

Identifying Frequent Users of an Urban Emergency Medical Service Using Descriptive Statistics and Regression Analyses

This retrospective cohort study provides a descriptive analysis of a population that frequently uses an urban emergency medical service (EMS) and identifies factors that contribute to use among all frequent users. For purposes of this study we divided frequent users into the following groups: low- frequent users (4 EMS transports in 2012), medium-frequent users (5 to 6 EMS transports in 2012), high-frequent users (7 to 10 EMS transports in 2012) and super-frequent users (11 or more EMS transports in 2012). Overall, we identified 539 individuals as frequent users. For all groups of EMS frequent users (i.e. low, medium, high and super) one or more hospital admissions, receiving a referral for follow-up care upon discharge, and having no insurance were found to be statistically significant with frequent EMS use (P<0.05). Within the diagnostic categories, 41.61% of super-frequent users had a diagnosis of "primarily substance abuse/misuse" and among low-frequent users a majority, 53.33%, were identified as having a "reoccurring (medical) diagnosis." Lastly, relative risk ratios for the highest group of users, super-frequent users, were 3.34 (95% CI [1.90-5.87]) for obtaining at least one referral for follow-up care, 13.67 (95% CI [5.60-33.34]) for having four or more hospital admissions and 5.95 (95% CI [1.80-19.63]) for having a diagnoses of primarily substance abuse/misuse. Findings from this study demonstrate that among low- and medium-frequent users a majority of patients are using EMS for reoccurring medical conditions. This could potentially be avoided with better care management. In addition, this study adds to the current literature that illustrates a strong correlation between substance abuse/misuse and high/super-frequent EMS use. For the subgroup analysis among individuals 65 years of age and older, we did not find any of the independent variables included in our model to be statistically significant with frequent EMS use.

Ambulance use in Pakistan: an analysis of surveillance data from emergency departments in Pakistan

Background

The utilization of ambulances in low- and middle-income countries is limited. The aim of this study was to ascertain frequency of ambulance use and characteristics of patients brought into emergency departments (EDs) through ambulance and non-ambulance modes of transportation.

Methods

The Pakistan National Emergency Departments Surveillance (Pak-NEDS) was a pilot active surveillance conducted in seven major tertiary-care EDs in six main cities of Pakistan between November 2010 and March 2011. Univariate and multivariate logistic regression was performed to investigate the factors associated with ambulance use.

Results

Out of 274,436 patients enrolled in Pak-NEDS, the mode of arrival to the ED was documented for 94. 9% (n = 260,378) patients, of which 4.1% (n = 10,546) came to EDs via ambulances. The mean age of patients in the ambulance group was significantly higher compared to the mean age of the non-ambulance group (38 ± 18.4 years versus 32.8 ± 14.9 years, p-value < 0.001). The most common presenting complaint in the ambulance group was head injury (12%) while among non-ambulance users it was fever (12%). Patients of all age groups were less likely to use an ambulance compared to those >45 years of age (p-value < 0.001) adjusted for gender, cities, hospital type, presenting complaint group and disposition. The adjusted odds ratio of utilizing ambulances for those with injuries was 3.5 times higher than those with non-injury complaints (p-value < 0.001). Patients brought to the ED by ambulance were 7.2 times more likely to die in the ED than non-ambulance patients after adjustment for other variables in the model.

Conclusion

Utilization of ambulances is very low in Pakistan. Ambulance use was found to be more among the elderly and those presenting with injuries. Patients presenting via ambulances were more likely to die in the ED.

Why do patients with 'primary care sensitive' problems access ambulance services? A systematic mapping review of the literature

OBJECTIVE

Emergency ambulance use for problems that could be managed in primary care continues to rise owing to complex reasons that are poorly understood. The objective of this systematic review is to draw together published evidence across a variety of study methodologies and settings to gain a better understanding of why patients seek help from ambulance services for these problems.

DESIGN

Systematic searches were undertaken across the MEDLINE, EMBASE, PsychINFO, CINAHL, Health Management Information Consortium and Health Management Information Service publication databases. Google Scholar, Web of Science, OpenSigle, EThOS and DART databases were also systematically searched for reports, proceedings, book chapters and theses, along with hand-searching of grey literature sources. Studies were included if they reported on findings examining patient, carer, health professional or service management interactions with ambulance services for primary care problems. All study methodologies and perspectives were of interest. Data were extracted, quality assessed and systematically mapped according to key findings through generation of an iterative framework.

RESULTS

A total of 31 studies met inclusion criteria. Findings were summarised across 5 broad categories: factors associated with individual patients; actions of care-givers and bystanders; population-level factors; health infrastructure factors; challenges faced by health professionals. A number of subcategories were developed to explore these factors in more detail.

CONCLUSIONS

This review reports important factors that may impact on ambulance use for primary care problems across a global setting, including demographic measures associated with deprivation, minority status and individual social circumstances. Categorising ambulance calls for primary care problems as 'inappropriate' is context dependant and may be unhelpful. Potential implications for triage and risk management strategies are discussed.

Trends of pre-hospital emergency medical services activity over 10 years: a population-based registry analysis

Background

The number of requests to pre-hospital emergency medical services (PEMS) has increased in Europe over the last 20 years, but epidemiology of PEMS interventions has little be investigated. The aim of this analysis was to describe time trends of PEMS activity in a region of western Switzerland.

Methods

Use of data routinely and prospectively collected for PEMS intervention in the Canton of Vaud, Switzerland, from 2001 to 2010. This Swiss Canton comprises approximately 10% of the whole Swiss population.

Results

We observed a 40% increase in the number of requests to PEMS between 2001 and 2010. The overall rate of requests was 35/1000 inhabitants for ambulance services and 10/1000 for medical interventions (SMUR), with the highest rate among people aged ≥ 80. Most frequent reasons for the intervention were related to medical problems, predominantly unconsciousness, chest pain respiratory distress, or cardiac arrest, whereas severe trauma interventions decreased over time. Overall, 89% were alive after 48 h. The survival rate after 48 h increased regularly for cardiac arrest or myocardial infarction.

Conclusion

Routine prospective data collection of prehospital emergency interventions and monitoring of activity was feasible over time. The results we found add to the understanding of determinants of PEMS use and need to be considered to plan use of emergency health services in the near future. More comprehensive analysis of the quality of services and patient safety supported by indicators are also required, which might help to develop prehospital emergency services and new processes of care.

The aging population and future demand for emergency ambulances in Japan

Demand for emergency ambulances has been increasing in developmentally advanced countries, and in Japan demand has been increasing due to the aging population since 2008, when the total population began to decrease. However, we do not know how acceleration of the aging population relates to the demand for emergency ambulances. Thus, we estimated future demand for emergency ambulances in Japan. A regression with autocorrelated errors model was used to estimate future demand for emergency ambulance dispatches and emergency transports. In the estimation, data on emergency ambulance dispatches, emergency transports, and population data from 1963 to 2011, and an estimate of the population of Japan from 2012 to 2025 were used. The number of emergency ambulance dispatches has increased since 2008, and it is expected to continue to increase until around 2023 or 2024, when it will reach a peak of ~6.2 million per year. Similarly, the number of emergency transports is expected to continue to increase until 2022 or 2023, when it will reach a peak of ~5.3 million per year. Although we need to be careful when evaluating numbers predicted for the remote future due to methodological limitations, the findings might be useful for updating emergency medical care systems to prepare for future increases in demand.

Variations in ambulance use in the United States: the role of health insurance

OBJECTIVES

The purpose of this study was to describe the associations between individual health insurance and ambulance utilization using a national sample of patients who receive emergency department (ED) care.

METHODS

The data source was the National Hospital Ambulatory Medical Care Survey, years 2004 through 2006. Noninstitutionalized patients between ages 18 and 65 years were included. The primary dependent variable was ambulance use. Multivariable logistic regression methods were used to assess the associations between health insurance status and ambulance use and to adjust for confounders.

RESULTS

A total of 61,013 ED visits were included, representing a national sample of approximately 70 million annual ED visits over 3 years. Ambulance transport was used in 11% of private insurance visits, 16% of Medicaid visits, and 13% of uninsured visits. In the adjusted model, visits by patients with Medicaid (adjusted odds ratio [aOR] = 1.60, 99% confidence interval (CI) = 1.37 to 1.86) and the uninsured (aOR = 1.43, 99% CI = 1.23 to 1.66) were more likely to arrive by ambulance than visits by patients with private insurance. Ambulance use among the uninsured was most pronounced in metropolitan areas.

CONCLUSIONS

Ambulance use varies by health insurance status. Medicaid coverage and lack of insurance are each independently associated with increased odds of ambulance use, suggesting a disproportionate role for emergency medical services (EMS) in the care of patients with limited financial resources.

The challenges of population ageing: accelerating demand for emergency ambulance services by older patients, 1995-2015

OBJECTIVE

To measure the growth in emergency ambulance use across metropolitan Melbourne since 1995, to measure the impact of population growth and ageing on these services, and to forecast demand for these services in 2015.

DESIGN AND SETTING

A population-based retrospective analysis of Ambulance Victoria's metropolitan emergency ambulance transportation data for the period from financial year 1994-95 to 2007-08, and modelling of demand in the financial year 2014-15.

MAIN OUTCOME MEASURES

Numbers and rates of emergency ambulance transportations.

RESULTS

The crude annual rate of emergency transportations across all age groups increased from 32 per 1000 people in 1994-95 to 58 per 1000 people in 2007-08. The rate of transportation for all ages increased by 75% (95% CI, 62%-89%) over the 14-year study period, representing an average annual growth rate of 4.8% (95% CI, 4.3%-5.3%) beyond that explained by demographic changes. Patients aged ≥ 85 years were eight times (incident rate ratio, 7.9 [95% CI, 7.6-8.3]) as likely to be transported than those aged 45-69 years over this period. Forecast models suggest that the number of transportations will increase by 46%-69% between 2007-08 and 2014-15, disproportionately driven by increasing usage by patients aged ≥ 85 years.

CONCLUSIONS

These findings confirm a dramatic rise in emergency transportations over the study period, beyond that expected from demographic changes. Rates increased across all age groups, but more so in older patients. In the future, such acceleration is likely to have major effects on ambulance services and acute hospital capacity. This calls for further investigation of underlying causes and alternative models of care.

Increasing utilisation of emergency ambulances

BACKGROUND

Increased ambulance utilisation is closely linked with Emergency Department (ED) attendances. Pressures on hospital systems are widely acknowledged with ED overcrowding reported regularly in the media and peer-reviewed literature. Strains on ambulance services are less well-documented or studied.

AIMS

To review the literature to determine the trends in utilisation of emergency ambulances throughout the developed world and to discuss the major underlying drivers perceived as contributing to this increase.

METHOD

A search of online databases, search engines, peer-reviewed journals and audit reports was undertaken.

FINDINGS

Ambulance utilisation has increased in many developed countries over the past 20 years. Annual growth rates throughout Australia and the United Kingdom are similar. Population ageing, changes in social support, accessibility and pricing, and increasing community health awareness have been proposed as associated factors. As the extent of their contribution has not yet been established these factors were reviewed.

CONCLUSION

The continued rise in utilisation of emergency ambulances is placing increasing demands on ambulance services and the wider health system, potentially compromising access, quality, safety and outcomes. A variety of factors may contribute to this increase and targeted strategies to reduce utilisation will require an accurate identification of the major drivers of demand.

Utilization of emergency medical services in a large urban area: description of call types and temporal trends

BACKGROUND

Emergency medical services (EMS) systems are used by the public for a range of medically related problems.

OBJECTIVE

To understand and analyze the patterns of EMS utilization and trends over time in a large urban EMS system so that we may better direct efforts toward improving those services.

METHODS

The 63 call type designations from all New York City (NYC) 9-1-1 EMS calls between 1999 and 2007 were obtained and grouped into 10 broad and 30 specific medical categories. Aggregated numbers of total EMS calls and individual categories were divided by NYC resident population estimates to determine utilization rates. Temporal trends were evaluated for statistical significance with Spearman's rho (ρ).

RESULTS

There were 9,916,904 EMS calls between 1999 and 2007, with an average of 1,101,878 calls/year. Utilization rates increased from 129.5 to 141.9 calls/1,000 residents/year over the study period (average annual rise of 1.16%). Among all medical/surgical call types (excluding trauma), there was an average annual increase of 1.8%/year. The most substantial increases were among "psychiatric/drug related" (+5.6%/year), "generalized illness" (+3.2%/year), and "environmental related" calls (+2.9%/year). The largest decrease was among "respiratory" calls (-1.2%/year), specifically for "asthma" (-5.0%/year). For trauma call types, there was an annual average decrease of 0.4%/year, with the category of "violence related" calls having the greatest decline (-3.3%/year).

CONCLUSION

There was an increase in overall EMS utilization rates, though not all call types rose uniformly. Rather, a number of significant trends were identified reflecting either changing medical needs or changing patterns of EMS utilization in NYC's population.

Path Analysis Modeling Indicates Free Transport Increases Ambulance Use for Minor Indications

INTRODUCTION

Clinically unnecessary ambulance transport is increasing, diverting limited resources from patients needing ambulance transport. It was anecdotally observed that inappropriate ambulance use increased after abolition of a direct patient cost for ambulance transport.

HYPOTHESIS

In July 2003, direct patient fees were abolished in favor of a universally applied ambulance levy, potentially leading to increased ambulance use by patients with low illness acuity and admission rates.

METHODS

The influence of age, illness acuity, and need for admission on ambulance use was assessed for 55,397 emergency department attendances in 2002 and 2004. Ambulance users were compared with nonusers in both years and attendances for 2002 compared with 2004 using chi-square test for two groups. Logistic regression provided a multivariate model leading to ambulance use. Path analysis modeling to assess interrelationships between factors associated with ambulance use was developed.

RESULTS

Ambulance users in both years were older, had more acute illness, and had greater need for admission compared with nonusers. The odds ratio (OR) of arrival by ambulance in 2004 compared with 2002 was 1.14 (95% confidence interval, [CI], 1.12 to 1.17). In 2002, ambulance users were older (OR, 1.42; 95% CI, 1.40 to 1.43), were more likely to need admission (OR, 2.28; 95% CI, 2.16 to 2.4) and had higher illness acuity (OR, 2.02; 95% CI, 1.94 to 2.09). There was a negative correlation between 2004 and illness acuity.

CONCLUSIONS

Ambulance use increased in 2004 after patient transport fees were abolished. Increased use was associated with decreased age, clinical acuity, and admission need. Abolishing direct patient cost stimulates ambulance use, potentially including inappropriate transport. Path analysis to assess the effect of changed funding on ambulance use could be used to the influence of other locally relevant factors contributing to ambulance use.

Influence of socioeconomic factors on medically unnecessary ambulance calls

Background

Unnecessary ambulance use has become a socioeconomic problem in Japan. We investigated the possible relations between socioeconomic factors and medically unnecessary ambulance calls, and we estimated the incremental demand for unnecessary ambulance use produced by socioeconomic factors.

Methods

We conducted a self-administered questionnaire-based survey targeting residents of Yokohama, Japan. The questionnaire included questions pertaining to socioeconomic characteristics, dichotomous choice method questions pertaining to ambulance calls in hypothetical nonemergency situations, and questions on the city's emergency medical system. The probit model was used to analyze the data.

Results

A total of 2,029 out of 3,363 targeted recipients completed the questionnaire (response rate, 60.3%). Probit regression analyses showed that several demographic and socioeconomic factors influence the decision to call an ambulance. Male respondents were more apt than female respondents to state that they would call an ambulance in nonemergency situations (p < 0.05). Age was an important factor influencing the hypothetical decision to call an ambulance (p < 0.05); elderly persons were more apt than younger persons to state that they would call an ambulance. Possession of a car and hesitation to use an ambulance negatively influenced the hypothetical decision to call an ambulance (p < 0.05). Persons who do not have a car were more likely than those with a car to state that they would call an ambulance in unnecessary situations.

Conclusion

Results of the study suggest that several socioeconomic factors, i.e., age, gender, household income, and possession of a car, influence a person's decision to call an ambulance in nonemergency situations. Hesitation to use an ambulance and knowledge of the city's primary emergency medical center are likely to be important factors limiting ambulance overuse. It was estimated that unnecessary ambulance use is increased approximately 10% to 20% by socioeconomic factors.

Expected Annual Emergency Miles per Ambulance: An Indicator for Measuring Availability of Emergency Medical Services Resources

CONTEXT

To ensure equitable access to prehospital care, as recommended by the Rural and Frontier Emergency Medical Services (EMS) Agenda for the Future, policymakers will need a uniform measure of EMS infrastructure.

PURPOSE AND METHODS

This paper proposes a county-level indicator of EMS resource availability that takes into consideration existing EMS resources (ambulances), population health and demographics, and geographic factors. The indicator, the EXpected annual emergency miles per AMBulance (EXAMB), provides a basis for comparing ambulance availability across counties within states. A method for calculating the EXAMB indicator is demonstrated using data from 5 states.

FINDINGS

The EXAMB indicator was negatively correlated with ambulance availability per 100,000 population in 4 of the 5 states in the study. The indicator was positively correlated with rurality in 3 states. In Mississippi, South Carolina, and Wyoming, whole-county health professional shortage areas had median EXAMB values 45%-81% higher than those of the non-health professional shortage areas counties.

CONCLUSIONS

Future research should explore the relationship of the EXAMB to EMS outcomes, with the ultimate goal of developing a nationally recognized indicator of "adequate" EMS resource availability.

National study of ambulance transports to United States emergency departments: importance of mental health problems

INTRODUCTION

Understanding ambulance utilization patterns is essential to assessing prehospital system capacity and preparedness at the national level.

OBJECTIVE

To describe the characteristics of patients transported to U.S. emergency departments (EDs) by ambulance and to determine predictors of ambulance utilization.

METHODS

Data were obtained from the National Hospital Ambulatory Medical Care Survey using mode of arrival, demographic and visit information, ICD-9-CM E and V-codes, and classified reasons for the visit.

RESULTS

The rates for ED visits of persons conveyed by ambulence were stable between 1997 and 2003, consisting of approximately one in every seven ED visits (14%). In 2003, there were 16.2 million ED visits for which an ambulance was used in the U.S. However, for patients with mental health visits, nearly one in three ED presentations (31%) arrived by ambulance. Significantly higher rates of ambulance use were associated with: (1) mental health visits; (2) older age; (3) African-Americans; (4) Medicare or self-pay insurance status; (5) urban ED location; (6) U.S. regions outside of the South; (7) presentation between 12 midnight to 0800 hours; (8) injury-related visits; (9) urgent visit status; and/or (10) those resulting in hospital admission. Among mental health patients, older age, self-pay insurance status, urban ED location, regions outside the southern US, and urgent visit classification predicted ambulance use. Ambulance usage within the mental health group was highest for suicide and lowest for mood and anxiety disorder-related visits.

CONCLUSION

Reliance on ambulance services varies by age, insurance status, geographic factors, time of day, urgency of visit, subsequent admission status, and type of mental health disorder. Even after controlling for many confounding factors, mental health problems remain an important predictor of ambulance use.

Impact of ambulance transportation on resource use in the emergency department

OBJECTIVE

To determine how ambulance transportation is associated with resource use in the emergency department (ED).

METHODS

A retrospective administrative database review of patient visits to a Montreal tertiary care hospital ED in one year (April 2000-March 2001). Measures of resource use included ED length of stay, admission to the hospital, and whether consultations and radiology/imaging tests (excluding plain-film x-rays) were ordered from the ED.

RESULTS

During the study period, 39,674 patients made 59,142 visits to the ED. Ambulance transportation was used for 15.6% of these ED visits. Compared with non-ambulance visits, ambulance visits were more likely to be made by older patients (mean age: 68 vs. 47 years), to be made by females (59% vs. 55%), to have a greater triage urgency score (mean on 1-5 scale, with 1 most urgent: 2.7 vs. 3.9), and to occur after office hours, 5 PM to 9 AM (47% vs. 43%). Ambulance visits were also more likely than non-ambulance visits to result in: a longer length of stay (mean: 13.3 hours [95% CI = 13.0 to 13.6] vs. 5.9 [95% CI = 5.8 to 6.0]), hospital admission (40% vs. 10%) (odds ratio [OR]: 5.94 [95% CI = 5.59 to 6.33]), consultations (56% vs. 20%) (OR: 5.15 [95% = 4.86 to 5.45]), and radiology/imaging tests (20% vs. 12%) (OR: 1.93 [95% CI = 1.81 to 2.07]). In multivariate models that adjusted for the effects of age, gender, triage urgency, and temporal factors, ambulance transportation maintained its association with greater resource use.

CONCLUSIONS

This preliminary study indicates that patients arriving at the ED by ambulance use significantly more resources than their walk-in counterparts.

Effect of socioeconomic status on out-of-hospital transport delays of patients with chest pain

STUDY OBJECTIVES

The effect of socioeconomic status on out-of-hospital care has not been widely examined. We determine whether socioeconomic status was associated with out-of-hospital transport delays for patients with chest pain.

METHODS

A retrospective study of patients with chest pain transported by means of ambulance in Toronto, Ontario, Canada, in 1999 was conducted. The primary outcome measure was the 90th percentile system response interval, with secondary outcomes being the 90th percentile on-scene interval, transport interval, and total out-of-hospital interval. Socioeconomic status was the primary independent variable. Covariates were age, sex, case severity, dispatch and return priority, time and day of transport, paramedic training, and percentage of high-rise apartments in the region.

RESULTS

Four thousand three hundred fifty-six patients met the inclusion criteria. The 90th percentile system response interval and total out-of-hospital interval were 11 minutes and 49 minutes, respectively. In multivariate analyses, the highest socioeconomic status neighborhoods were significantly associated with decreased system response interval (34.0 seconds; 95% confidence interval [CI] 6.2 to 70.9 seconds) and transport interval (132.3 seconds; 95% CI 24.1 to 229.6 seconds). In addition, age (+45.3 seconds per 10 years; 95% CI 13.3 to 75.1 seconds), female sex (+205.0 seconds; 95% CI 78.1 to 287.7 seconds), and advanced care paramedic crews (+371.6 seconds; 95% CI 263.3 to 490.1 seconds) were associated with delays in total out-of-hospital interval. Lastly, calls originating from the highest socioeconomic status neighborhoods were dispatched the highest proportion of advanced care paramedic crews, despite similar dispatch priorities and case severities.

CONCLUSION

High socioeconomic status neighborhoods were associated with shorter out-of-hospital transport intervals for patients with chest pain. In addition, out-of-hospital delays were associated with age, sex, and advanced care paramedic crew type, with calls from the highest socioeconomic status neighborhoods being most likely to receive advanced care paramedic crews.

Predictors and outcomes of frequent emergency department users

OBJECTIVE

To identify predictors and outcomes associated with frequent emergency department (ED) users.

METHODS

Cross-sectional intake surveys, medical chart reviews, and telephone follow-up interviews of patients presenting with selected chief complaints were performed at five urban EDs during a one-month study period in 1995. Frequent use was defined by four or more self-reported, prior ED visits. Multivariate logistic regression identified predictors of frequent ED visitors from five domains (demographics, health status, health access, health care preference, and severity of acute illness). Associations between high use and selected outcomes were assessed with logistic regression models.

RESULTS

All study components were completed by 2,333 of 3,455 eligible patients (67.5%). Demographics predicting frequent use included being a single parent, single or divorced marital status, high school education or less, and income of less than $10,000 (1995). Health status predictors included hospitalization in the preceding three months, high ratings of psychological distress, and asthma. Health access predictors included identifying an ED or a hospital clinic as the primary care site, having a primary care physician (PCP), and visiting a PCP in the past month. Choosing the ED for free care was the only health preference predictive of heavy use. Illness severity measures were higher in frequent visitors, although these were not independently predictive in the multivariate model. Outcomes correlated with heavy use include increased hospital admissions, higher rates of ED return visits, and lower patient satisfaction, but not willingness to return to the ED or follow-up with a doctor.

CONCLUSIONS

Frequent ED visits are associated with socioeconomic distress, chronic illness, and high use of other health resources. Efforts to reduce ED visits require addressing the unique needs of these patients in the emergency and primary care settings.

The pattern of ambulance arrivals in the emergency department of an acute care hospital in Singapore

OBJECTIVES

(1) To determine the pattern of ambulance arrivals in the emergency department (ED) and (2) to review resource allocation based on these data.

METHODS

All (13 697) ambulance arrivals in 1996 to the ED of Tan Tock Seng Hospital were studied and where relevant compared with the walk in and total arrivals of the same year. The following data were obtained from computer records: (a) patients' demographic data; (b) number of ambulance arrivals by hour; (c) the classification of the ambulance arrivals by emergency or non-emergency, trauma or non-trauma; (d) cause of injury for trauma cases; (e) discharge status.

RESULTS

The ambulance arrivals in 1996 constituted 12.4% of the patient load for this department. There was no difference in modes of patient arrival to the ED by sex and ethnic group. However, there was significant evidence to show that more patients age > 60 came by ambulance than those age < 12 (p << 0.01). Some 98.5% of the ambulance arrivals were emergencies; 40.7% of the ambulance arrivals were attributable to trauma versus 27.3% of the walk in arrivals. The majority of the trauma cases brought in by ambulance were because of road traffic accidents (15.3%) or home accidents (7.4%). The peak in ambulance arrivals was between 2100-2300 hours compared with 1000-1200 for the walk in arrivals. More than half of the ambulance arrivals were admitted.

CONCLUSION

In planning resource allocation and in the development of contingency plans, the resource use of ambulance patients and the pattern of their arrivals should be taken into account.

Delay in seeking emergency care

OBJECTIVE

To determine whether patient clinical and socioeconomic characteristics predict patient delay in coming to the emergency department (ED).

METHODS

Adult ED patients at five urban teaching hospitals were surveyed regarding self-reported delay in coming to the ED. Delay was measured by self-perception as well as by the number of days ill and unable to work. Patient socioeconomic and clinical characteristics were obtained by survey questionnaire and chart review. Cross-sectional analysis within a prospective study of 4,094 consecutive patients was performed using a subset of 1,920 patients (84% eligible rate) to whom questionnaires were administered.

RESULTS

Overall, 32% of the patients completing the survey reported delay in seeking ED care. Of these patients reporting delay, 71% thought their problem would go away or was not serious. Patients who were older, had higher acuity, or were frequent ED users reported less delay in coming to the ED, while patients without a regular physician or who were African American reported more delay. Perception of increased number of days ill prior to visiting the ED was reported by frequent ED users and those with worse baseline physical function, while patients who had higher acuity reported fewer days ill prior to coming to the ED.

CONCLUSIONS

A patient's decision to delay coming to the ED often reflects a belief that his or her illness is either self-limited or not serious. The decision to delay correlates with patient characteristics and access to a regular physician. The correlates of delay in seeking ED care may depend on the delay measure used. Better understanding of patients at risk for delaying care may influence interventions to reduce delay.

Patterns of use of emergency medical transport: a population-based study

The objective of this study was to characterize population-based emergency medical service (EMS) use rates and examine some of the factors associated with usage of prehospital services. The design was a population-based observational study with multiple regression analysis. Transports reported by prehospital services to the Kentucky Emergency Medical Services Information System from Kentucky counties in which all EMS units submit computerized data was the data source. There were 102,321 emergent transports reported. The overall rate of use of EMS transports was 51.7 +/- 24.1/1,000/year, but the rate varied between different communities (range 11 to 139/1,000/year). Rate of use was highest in those older than 65 (178.5 +/- 84.2/1,000/year), with the rate increasing exponentially with increasing age in this age group. Reasons for transport were age dependent. There was an association between increasing poverty level and use of EMS. In addition, the absence of 911 service (odds ratio [OR] 1.18, 95% confidence interval [CI; 1.14,1.22]) and the absence of a hospital in the county (OR 1.27, 95% CI [1.24,1.30]) were also associated with increasing rates of ambulance use. Rates of use of EMS are most dependent on age and cause, but use is also correlated with increasing levels of poverty. Wide variations in use between communities suggests that point estimates using one community may over- or underestimate EMS usage.

Predictors of Demand for Emergency Prehospital Care: An Australian Study

Introduction:

Determining the predictors of demand for emergency prehospital care can assist ambulance services in undertaking policy and planning activities.

Hypothesis:

Demand for prehospital care can be explained by demographic, health status, and economic determinants.

Methods:

The study used a cross-sectional design to investigate the association of demographic, health status, and insurance factors with the use of prehospital, ambulance care. Core data items including age, gender, marital status, country of origin, triage score, diagnosis, time of presentation, method of arrival, and patient disposition were collected for every patient who pre-sented at the Emergency Department of the study hospital over a four-month period. Ambulance usage was analysed using Poisson regression.

Results:

For the 10,229 patients surveyed, only a small number were triaged as having the highest level of urgent medical need (0.8%), but the majority of these used prehospital emergency medical care (90.2%). Predictors of ambulance use included age >65years (Prevalence Ratio [Prevalence Ratio] = 2.92; 95% confidence interval [ Confidence Interval]: 2.35–3.63), being married or in a defacto relationship (Prevalence Ratio = 0.69; 95% Confidence Interval: 0.60–0.79) or divorced, separated, or widowed (Prevalence Ratio = 0.83; 95% Confidence Interval: 0.70–0.98), triage score level 1 or 2 (Prevalence Ratio = 1.95; 95% Confidence Interval: 1.68–2.28), or triage score level 3 (Prevalence Ratio = 1.54; 95% Confidence Interval: 1.38–1.72), diagnosis involving either mental (Prevalence Ratio = 4.29; 95% Confidence Interval: 1.84–10.01), nervous (Prevalence Ratio = 2.74; 95% Confidence Interval: 1.19–6.31) or trauma (Prevalence Ratio = 2.33; 95% Confidence Interval: 1.03–5.27) conditions, and insurance status (Prevalence Ratio =1.54; 95% Confidence Interval: 1.40–1.71). Ethnicity, gender, and time of day were not associated with usage.

Conclusion:

Demand for ambulance services can be predicted by a number of demographic, medical status, and insurance variables. Age and triage levels are key influences on demand for ambulance services. Ambulance insurance status provides an economic incentive to use ambulance services regardless of the urgency of the medical condition.

The potential benefit of a home fire safety intervention during emergency medical services calls

OBJECTIVE

To determine how often house fires occur at 1- and 2-family dwellings visited previously by emergency medical services (EMS) personnel and whether these visits were missed opportunities for a point-of-contact home fire safety intervention.

METHODS

A retrospective, consecutive, case series analysis of all Milwaukee Fire Department alarm responses during 1994 was performed. Measurements included date of service, type of response, property type, dollar loss estimate, number of injuries and fatalities, cause of alarm, and presence of an operational smoke detector. Descriptive, chi2, and relative risk statistics were used to describe the relationship between EMS responses and fire responses at 1- and 2-family dwellings.

RESULTS

The Milwaukee Fire Department dispatched 94,378 requests for service to 43,556 addresses. 16,150 addresses generated multiple requests; 7.2% (1,162/16,150) were for an "alarm of fire" response [relative risk 1.83 (95% CI: 1.69-1.99) for addresses with multiple requests vs those with a single request for service]. Most [62% (721/1,162)] of the addresses were visited by EMS personnel prior to the alarm; 28% (205/721) were 1- and 2-family dwellings. A mean of 1.8 (376/205) EMS responses occurred prior to the "alarm of fire" response; 121 addresses received 1 response, 46 received 2, 18 received 3, and 20 received > or = 4 responses. Of 169 addresses with complete data, there was a total fire dollar loss of $1,963,020 (1994) along with 32 injuries and 0 fatalities. While 47% (80/169) of the 1- and 2-family dwellings had a smoke detector present, only 17% (29/169) of the dwellings had an operational smoke detector.

CONCLUSIONS

A point-of-contact home fire safety intervention appears of potential benefit for frequent users of EMS care. Determination of the presence of an operational smoke detector in 1- and 2-family dwellings may be a useful injury prevention act during such EMS calls.