Association between EMS Workforce Density and Population Health Outcomes in the U.S.

BACKGROUND: The prehospital care provided by emergency medical services (EMS) personnel is a critical component of the public health, public safety, and health care systems in the U.S.; however, the population-level value of EMS care is often overlooked. No studies have examined how the density of EMS personnel relates to population-level health outcomes. Our objectives were to examine the geographic distribution and density of EMS personnel in the U.S.; and quantify the association between EMS personnel density and population-level health outcomes. METHODS: We conducted a cross-sectional evaluation of county-level EMS personnel density using estimates from the National Registry of Emergency Medical Technicians in nine states that require continuous national certification (Alabama, Louisiana, Massachusetts, Minnesota, New Hampshire, North Dakota, South Carolina, Vermont, and Washington, D.C.). Outcomes of interest included life expectancy, all-cause mortality, and cardiac arrest mortality. We used quantile regression models to examine the association between a 10-person increase in EMS personnel density and each outcome at the 10th, 50th (median), and 90th percentiles, controlling for population characteristics and area health resources. RESULTS: There were 356 counties included, with a mean EMS density of 223 EMS personnel per 100,000 population. Density was higher in rural compared to urban counties (247 versus 186 per 100,000 population; p = 0.001). In unadjusted models, there was a significant association between increase in EMS personnel density and an increase in life expectancy at each examined percentile (e.g., 50th percentile, increase of 52.9 days; 95% CI 40.2, 65.5; p < 0.001), decrease in all-cause mortality at each examined percentile, and decrease in cardiac arrest mortality at the 50th and 90th percentiles. These associations were not statistically significant in the adjusted models. CONCLUSIONS: EMS personnel density differs between urban and rural areas, with higher density per population in rural areas. There were no statistically significant associations between EMS density and population-level health outcomes after controlling for population characteristics and other health resources. The best approach to quantifying the community-level value that EMS care may or may not provide remains unclear.

Emergency Medical Services Management of Bronchospasm in the United States: A Cross-Sectional Analysis and Nationwide Quality Assessment.

Background/Objective: Bronchospasm, caused by asthma and other related conditions, is a significant cause of morbidity and mortality commonly managed by emergency medical services (EMS). We aimed to evaluate the quality of prehospital management of bronchospasm by EMS in the US.Methods: The National EMS Information System Public Release Research dataset, a nationwide convenience sample of prehospital patient care report data from 2018 to 2019, was used to capture 9-1-1 activations where patients aged ≥2 years were treated and transported by EMS for suspected bronchospasm. First, we described the extent to which EMS care met eight quality measures identified from available statewide EMS protocols, existing quality measures, and national guidelines. Second, we quantified the extent of risk-standardized agency-level variation in administration of inhaled beta agonists and systemic corticosteroids using logistic regression models, accounting for patient characteristics, severity, and clustering by agencies. Third, we compared rates of completed prehospital interventions between pediatric (age <18 years) versus adult patients using two-sample t-tests.Results: A total of 1,336,988 EMS encounters for suspected bronchospasm met inclusion criteria. Median age of patients was 66 years, with only 4% pediatric; 55% were female. Advanced life support (ALS) units managed 94% of suspected bronchospasm. Respiratory rate (98%) and pulse oximetry (96%) were documented in nearly all cases. Supplemental oxygen was administered to hypoxic patients by 65% of basic life support (BLS) and 73% of ALS units. BLS administered inhaled beta-agonist therapy less than half the time (48%), compared to 77% by ALS. ALS administered inhaled anticholinergic therapy in 38% of cases, and systemic corticosteroids in 19% of cases. Pediatric patients were significantly less likely to receive supplemental oxygen when hypoxic, inhaled beta-agonists, inhaled anticholinergics, or systemic corticosteroids.Conclusions: We found important gaps in recent EMS practice for prehospital care of suspected bronchospasm. We highlight three targets for improvement: inhaled beta-agonist administration by BLS, systemic corticosteroid administration by ALS, and increased interventions for pediatric patients. These findings indicate important areas for research, protocol modification, and quality improvement efforts to improve EMS management of bronchospasm.

Patients who use emergency medical services have greater severity of illness or injury compared to those who present to the emergency department via other means: A retrospective cohort study.

Objective: We aimed to evaluate the differences in characteristics and illness/injury severity among patients who present to the emergency department (ED) via emergency medical services (EMS) compared to patients who present via other means. Methods: We analyzed a nationwide sample of ED visits from the 2015-2019 National Hospital Ambulatory Medical Care Survey. We excluded patients <18 or >92 years old, who eloped or left against medical advice, or who arrived via interfacility transport. Mode of presentation was dichotomized to those presenting to the ED via EMS versus any other mode of transportation. Using the appropriate survey sampling weights, we described patient characteristics and compared measures of illness/injury severity between groups using a multivariable logistic regression model. Results: An unweighted total of 73,397 ED visits, representing a weighted estimate of 528,083,416 ED visits in the United States during 2015-2019, included 18% arriving via EMS and 82% via other means. EMS patients were older, more often male, more often had multiple chronic medical conditions, and less often had private insurance. EMS patients had higher priority triage scores, consumed more resources in the ED, and had longer lengths of stay. Arrival by EMS was associated with higher odds of hospital admission (odds ratio [OR] 2.7, 95% confidence interval [CI] 2.4-2.9) and in-hospital mortality (OR 11.1, 95% CI 7.3-17.2). Conclusions: Patients presenting via EMS had significantly different characteristics and outcomes than those presenting via other means. These important differences should be considered when comparing studies of all ED patients versus those who present via EMS.

A retrospective review of out of hospital cardiac arrest at Gillette Stadium: 10 years of experience at a large sports venue.

Introduction: Rates of out-of-hospital cardiac arrest (OHCA) at major sporting events are as high as 0.7 per 100,000 attendees. However, factors contributing to OHCA at mass gatherings have not been well-described. We describe our experience with ten years of medical oversight and OHCA care at a professional football stadium. Methods: We performed a retrospective review of OHCA events between August 2010 and January 2020 at a 65,878-seat football stadium, with a single transporting EMS agency and a single receiving hospital. We analyzed EMS incident reports and matched patients to hospital records for outcome data. Results: A total of 7,767,345 people attended 115 football games during the study period. There were 21 OHCAs (0.27 per 100,000 attendees). Ninety-five percent of OHCAs were witnessed and 71.4% had an initial shockable rhythm, with bystander AED use in 47.6%. Median EMS response time was 2 minutes (IQR 1-6). For 7 patients defibrillated by EMS, time to defibrillation was 4 minutes (IQR 4-11). Return of spontaneous circulation (ROSC) occurred in 71%, with 47% having good 30-day neurologic survival. All patients with an initial rhythm of asystole died. Conclusion: The ROSC rate at our stadium exceeded 70% with almost half surviving with good neurologic outcomes, substantially higher than that reported for the general public. We hope that our experience will provide valuable lessons to other similarly sized stadiums.

Twenty Years After the EMS Research Agenda: Trends in Emergency Medical Services Publications and Research Funding.

STUDY OBJECTIVE: Since its publication in 2001, the National EMS Research Agenda has brought attention to a relative paucity of emergency medical services (EMS)-specific research and has called for an increase in funding and infrastructure to support EMS research. We investigated the trends in EMS-specific publications and National Institutes of Health (NIH)-funded research grants in the 20 years since this landmark publication. METHODS: We performed a structured PubMed search of English-language citations from 2001 to 2020 to identify publications with populations, settings, or topics related to EMS care, education, or operations. Publications in trade journals and studies not involving humans were excluded. We also queried NIH Research Portfolio Online Reporting Tools Expenditures and Results (RePORTER) using a similar structured search. Titles, keywords, and abstracts were reviewed. Descriptive statistics were calculated, and nonlinear trends were described using segmented regression models. RESULTS: A total of 183,307 references met the search criteria in PubMed, and 4,281 grants were identified in NIH RePORTER. After removing duplicates, 152,408 titles were screened, with 17,314 (11.5%) included. EMS-related publications increased from 419 in 2001 to 1,788 in 2020, a 327% increase, compared with a 197% increase in total PubMed publications. There was a statistically significant nonlinear (J-shaped) increase in EMS publications after 2007. There were 1,166 funded EMS-related NIH grants, with a 469% increase from 2001 to 2020 compared with an 18% increase in overall NIH awards. CONCLUSION: Although total publications have doubled in the United States over the past 20 years, EMS-specific research has more than tripled and the number of funded EMS research grants has increased nearly 5-fold. Future evaluation should examine the quality of this research and its application to clinical practice.

Out-of-Hospital Presentation and Management of Asthma and Chronic Obstructive Pulmonary Disease Exacerbations in the United States: A Nationwide Retrospective Cohort Study.

STUDY OBJECTIVE: To describe the demographic, clinical, and emergency medical service (EMS) response characteristics associated with EMS activations for asthma and chronic obstructive pulmonary disease (COPD) exacerbations in the US. METHODS: Using a nationwide set of out-of-hospital patient care report data from 2018 to 2019, we analyzed 9-1-1 EMS activations where asthma/COPD exacerbation was indicated by symptom, impression, or treatment provided. We excluded patients with ages less than 2 years or unknown, nonemergency transports, and encounters with any indication of anaphylaxis. Demographic, clinical, and EMS response characteristics were described for pediatric and adult patients with asthma/COPD exacerbations. RESULTS: A total of 1,336,988 asthma/COPD exacerbations were included, comprising 5% of qualifying 9-1-1 scene activations from 2018 to 2019. Most patients were adults (96%). Most adult patients were female (55%), whereas most pediatric patients were male (58%). Most activations occurred in urban settings (82%), particularly in pediatric patients (90%). Most asthma/COPD exacerbations were managed by advanced life support units (94%). Inhaled bronchodilators and systemic corticosteroid therapy were administered to 75% and 14% of all patients, respectively. Adults more often had oxygen saturation <92% (43% vs 20% of pediatric patients) and were more often treated with assisted ventilation (9% vs 1%). CONCLUSION: In this large nationwide sample of 9-1-1 activations treated and transported by EMS, 5% were for asthma/COPD exacerbation. Future work should focus on evidence-based standardization of EMS protocols and practice for asthma/COPD exacerbations to improve the quality of EMS care.

Trends in demographic and employment characteristics of US emergency medical technicians and paramedics, 2011-2019.

Background: Describing the US emergency medical services workforce is important to understand gaps in recruitment and retention and inform efforts to improve diversity. Our objective was to describe the characteristics and temporal trends of emergency medical technicians (EMTs) and paramedics in the United States. Methods: We performed a repeated cross-sectional evaluation of US Census Bureau's American Community Survey 1-year Public Use Microdata Sample data sets from 2011-2019. We included respondents working as an EMT or paramedic. Survey-weighted descriptive statistics of demographic and employment characteristics were calculated. Trend analysis was conducted using joinpoint regression to estimate slope and annual percent change (APC). Results: The total estimated number of EMTs and paramedics in the United States increased from 216,310 (95%CI 204,957-227,663) in 2011 to 289,830 (95%CI 276,918-302,743) in 2019 (APC 3.0%; 95%CI 1.4%, 4.7%). There was a slight increase in the proportion of females (2011, 31%; 2019, 35%). There was a significant decrease in proportion of non-Hispanic whites (2011, 80%; 2019, 72%; APC -1.5%; 95%CI -2.0%, -0.9%) with concurrent increases in other racial/ethnic groups (e.g., Hispanics, 2011, 10%; 2019, 13%). About half worked >40 hours per week, with little change over time. Between 15% and 18% lived and worked in different states, and about 40% traveled ≥30 minutes to their workplace. Conclusions: The number of EMTs and paramedics actively working in EMS as their primary paid occupation has increased over time. However, there have been only modest changes in their demographic diversity.

Objective Measurement of Learners' Cognitive Load During Simulation-Based Trauma Team Training: A Pilot Study.

INTRODUCTION: Literature has shown cognitive overload which can negatively impact learning and clinical performance in surgery. We investigated learners' cognitive load during simulation-based trauma team training using an objective digital biomarker. METHODS: A cross-sectional study was carried out in a simulation center where a 3-h simulation-based interprofessional trauma team training program was conducted. A session included three scenarios each followed by a debriefing session. One scenario involved multiple patients. Learners wore a heart rate sensor that detects interbeat intervals in real-time. Low-frequency/high-frequency (LF/HF) ratio was used as a validated proxy for cognitive load. Learners' LF/HF ratio was tracked through different phases of simulation. RESULTS: Ten subjects participated in 12 simulations. LF/HF ratios during scenario versus debriefing were compared for each simulation. These were 3.75 versus 2.40, P < 0.001 for scenario 1; 4.18 versus 2.77, P < 0.001 for scenario 2; and 4.79 versus 2.68, P < 0.001 for scenario 3. Compared to single-patient scenarios, multiple-patient scenarios posed a higher cognitive load, with LF/HF ratios of 3.88 and 4.79, P < 0.001, respectively. CONCLUSIONS: LF/HF ratio, a proxy for cognitive load, was increased during all three scenarios compared to debriefings and reached the highest levels in a multiple-patient scenario. Using heart rate variability as an objective marker of cognitive load is feasible and this metric is able to detect cognitive load fluctuations during different simulation phases and varying scenario difficulties.

Association between sleep characteristics, ideal cardiovascular health, and systemic inflammation, NHANES 2017-2018.

There is conflicting evidence regarding the associations between sleep deprivation and inflammatory biomarkers indicative of cardiovascular disease risk, such as high-sensitivity C-reactive protein (hsCRP). The association between sleep habits and hsCRP was quantified in a nationally representative sample of adults in the United States and mediation by ideal cardiovascular health metrics was explored. A cross-sectional analysis of cardiovascular disease-free participants aged 20-79 years from the 2017-2018 National Health and Nutrition Examination Survey was conducted. The primary exposures were self-reported sleep duration, sleep debt (difference between the average weekday and weekend sleep duration), and ideal cardiovascular health (11-14 points). The primary outcome was hsCRP (high-risk ≥ 3.0 mg/L). Multivariable robust Poisson models were used to estimate prevalence ratios after multiple imputation. A subgroup analysis of shift workers was also conducted. Of 4027 participants included (mean age 46 years; 52% female; 41% shift workers), the prevalence of sleeping <6 h on weekdays was 9%, with 40% sleeping ≥9 h on weekends. One-quarter had a high (≥2 h) sleep debt, 82% had poor cardiovascular health, and 34% had high-risk hsCRP. There were no significant associations between weekday sleep duration or sleep debt with high-risk hsCRP, even among shift workers. Mediation analysis was not conducted. Ideal cardiovascular health was associated with a lower prevalence of high-risk hsCRP (prevalence ratios, 0.60, 95% CI, 0.48-0.75). The lack of significant associations suggests a complex interrelationship of hsCRP with factors beyond sleep duration. Examination of populations at highest risk of chronic sleep deprivation could help to elucidate the association with systemic inflammation-related outcomes.

Critical Concepts for COVID-19 Mass Vaccination Site Operations.

Mass vaccination campaigns have been used effectively to limit the impact of communicable disease on public health. However, the scale of the coronavirus disease (COVID-19) vaccination campaign is unprecedented. Mass vaccination sites consolidate resources and experience into a single entity and are essential to achieving community ("herd") immunity rapidly, efficiently, and equitably. Health care systems, local and regional public health entities, emergency medical services, and private organizations can rapidly come together to solve problems and achieve success. As medical directors at several mass vaccination sites across the United States, we describe key mass vaccination site concepts, including site selection, operational models, patient flow, inventory management, staffing, technology, reporting, medical oversight, communication, and equity. Lessons learned from experience operating a diverse group of mass vaccination sites will help inform not only sites operating during the current pandemic, but also may serve as a blueprint for future outbreaks of highly infectious communicable disease.

The impact of COVID-19 on statewide EMS use for cardiac emergencies and stroke in Massachusetts.

OBJECTIVE: To evaluate the impact of coronavirus disease 2019 (COVID-19) on emergency medical services (EMS) use for time-sensitive medical conditions. We examined EMS use for cardiac arrest, stroke, and other cardiac emergencies across Massachusetts during the peak of the COVID-19 pandemic, evaluating their relationship to statewide COVID-19 incidence and a statewide emergency declaration. METHODS: A retrospective analysis of all EMS calls between February 15 and May 15, 2020 and the same time period for 2019. EMS call volumes were compared before and after March 10, the date of a statewide emergency declaration. RESULTS: A total of 408,758 calls were analyzed, of which 49,405 (12.1%) represented stroke, cardiac arrest, or other cardiac emergencies. Average call volume before March 10 was similar in both years but decreased significantly after March 10, 2020 by 18.7% (P < 0.001). Compared to 2019, there were 35.6% fewer calls for cardiac emergencies after March 10, 2020 (153.6 vs 238.4 calls/day, P < 0.001) and 12.3% fewer calls for stroke (40.0 vs 45.6 calls/day, P = 0.04). Calls for cardiac arrest increased 18.2% (28.6 vs 24.2 calls/day, P < 0.001). Calls for respiratory concerns also increased (208.8 vs 199.7 calls/day, P < 0.001). There was no significant association between statewide incidence of COVID-19 and EMS call volume. CONCLUSIONS: EMS use for certain time-sensitive conditions decreased after a statewide emergency declaration, irrespective of actual COVID-19 incidence, suggesting the decrease was related to perception instead of actual case counts. These findings have implications for public health messaging. Measures must be taken to clearly inform the public that immediate emergency care for time-sensitive conditions remains imperative.

Presymptomatic Transmission of Severe Acute Respiratory Syndrome Coronavirus 2 Among Residents and Staff at a Skilled Nursing Facility: Results of Real-time Polymerase Chain Reaction and Serologic Testing.

High rates of asymptomatic coronavirus disease 2019 infection suggest benefits to routine testing in congregate care settings. Screening was undertaken in a single nursing facility without a known case of coronavirus disease 2019, demonstrating an 85% prevalence among residents and 37% among staff. Serology was not helpful in identifying infections.

Improving Pediatric Administrative Disaster Preparedness Through Simulated Disaster Huddles.

Members of an emergency department (ED) staff need to be prepared for mass casualty incidents (MCIs) at all times. Didactic sessions, drills, and functional exercises have shown to be effective, but it is challenging to find time and resources for appropriate training. We conducted brief, task-specific drills (deemed "disaster huddles") in a pediatric ED (PED) to examine if such an approach could be an alternative or supplement to traditional MCI training paradigms. Over the course of the study, we observed an improving trend in the overall score for administrative disaster preparedness. Disaster huddles may be an effective way to improve administrative disaster preparedness in the PED. Low-effort, low-time commitment education could be an attractive way for further disaster preparedness efforts. Further studies are indicated to show a potential impact on lasting behavior and patient outcomes.

Ambulance Calls for Substance-Related Issues Before and After COVID-19.

Background: The United States is currently facing 2 epidemics: sustained morbidity and mortality from substance use and the more recent COVID-19 pandemic. We tested the hypothesis that the pandemic has disproportionately affected individuals with substance use disorder by evaluating average daily 9-1-1 ambulance calls for substance use-related issues compared with all other calls. Methods: This was a retrospective cross-sectional analysis of 9-1-1 ambulance calls before and after the start of COVID-19 in Massachusetts. We used consecutive samples of 9-1-1 ambulance calls, categorized into those which were substance-related or not. An interrupted time series analysis was performed to determine if there were changes in numbers of daily calls before a statewide declaration of emergency for COVID-19 (February 15-March 9, 2020), from the emergency declaration until a stay-at-home advisory (March 10-March 22, 2020) and following the stay-at-home advisory (March 23-May 15, 2020). Results: Compared with prior to the statewide emergency, the post-statewide emergency average of daily ambulance calls decreased from 2,453.2 to 1,969.6, a 19.7% decrease. Similarly, calls for substance-related reasons decreased by 16.4% compared with prior to the statewide emergency. However, despite an initial decrease in calls, after the stay-at-home advisory calls for substance use began increasing by 0.7 (95% confidence interval (CI) 0.4-1.1) calls/day, while calls for other reasons did not significantly change (+1.2 (95% CI -0.8 to 3.1) calls/day). Refusal of transport for substance-related calls increased from 5.0% before the statewide emergency to 7.5% after the declaration (p < 0.001). Conclusions: After an initial decline in substance-related ambulance calls following a statewide declaration of emergency, calls for substance use increased to pre-COVID-19 levels, while those for other reasons remained at a lower rate. The results suggest that COVID-19 is disproportionately affecting individuals with substance use disorder.

Defining a Research Agenda for Layperson Prehospital Hemorrhage Control: A Consensus Statement.

Importance: Trauma is the leading cause of death for US individuals younger than 45 years, and uncontrolled hemorrhage is a major cause of trauma mortality. The US military's medical advancements in the field of prehospital hemorrhage control have reduced battlefield mortality by 44%. However, despite support from many national health care organizations, no integrated approach to research has been made regarding implementation, epidemiology, education, and logistics of prehospital hemorrhage control by layperson immediate responders in the civilian sector. Objective: To create a national research agenda to help guide future work for prehospital hemorrhage control by laypersons. Evidence Review: The 2-day, in-person, National Stop the Bleed (STB) Research Consensus Conference was conducted on February 27 to 28, 2019, to identify and achieve consensus on research gaps. Participants included (1) subject matter experts, (2) professional society-designated leaders, (3) representatives from the federal government, and (4) representatives from private foundations. Before the conference, participants were provided a scoping review on layperson prehospital hemorrhage control. A 3-round modified Delphi consensus process was conducted to determine high-priority research questions. The top items, with median rating of 8 or more on a Likert scale of 1 to 9 points, were identified and became part of the national STB research agenda. Findings: Forty-five participants attended the conference. In round 1, participants submitted 487 research questions. After deduplication and sorting, 162 questions remained across 5 a priori-defined themes. Two subsequent rounds of rating generated consensus on 113 high-priority, 27 uncertain-priority, and 22 low-priority questions. The final prioritized research agenda included the top 24 questions, including 8 for epidemiology and effectiveness, 4 for materials, 9 for education, 2 for global health, and 1 for health policy. Conclusions and Relevance: The National STB Research Consensus Conference identified and prioritized a national research agenda to support laypersons in reducing preventable deaths due to life-threatening hemorrhage. Investigators and funding agencies can use this agenda to guide their future work and funding priorities.