Emergency Medical Services System Research Articles

Development of the National Prehospital Pediatric Readiness Project assessment

AbstractIntroductionIn the United States (US), the quality of care provided to children during emergencies is highly variable. Following implementation of the National Pediatric Readiness Project (NPRP), inclusive of two national online assessments of Emergency Departments (EDs), national organizations involved in Emergency Medical Services (EMS) systems convened to launch the Prehospital Pediatric Readiness Project (PPRP). The PPRP seeks to ensure high‐quality pediatric prehospital emergency care for all children. One of the first priorities of PPRP is to assess the current level of pediatric readiness in EMS systems. The development of the first comprehensive national assessment of pediatric readiness in EMS systems is described.MethodsThe 2020 joint policy statement, “Pediatric Readiness in Emergency Medical Services Systems” and the associated prehospital pediatric readiness checklist served as the foundation for the PPRP assessment. Assessment questions and scoring algorithm were developed using a modified Delphi process. The PPRP Assessment was converted into an online format comprising a website (EMSpedsReady.org), the online assessment, a personalized gap report, and non‐public Tableau data‐monitoring dashboards. A directory of all eligible EMS agencies in the United Staters was created to track participation. A diverse cohort of 15 EMS agencies piloted of the assessment questions and the online version of the assessment. Feedback from the pilot was integrated.ConclusionThe inaugural PPRP Assessment was open access May through July 2024, and the results will be used to guide future PPRP efforts.

Use of Emergency Mental Health Dispatch Training by a 9-1-1 Medical Dispatcher Assisting a Caller Expressing Suicidal Intent: A Case Report.

A growing number of individuals with unmet mental health needs in the United States rely on emergency medical services during mental health crises, and 9-1-1 emergency medical dispatchers (EMD) are often a critical lifeline to help. Unfortunately, current industry-standard dispatching protocols and training required for EMD certification largely lack specificity for managing 9-1-1 calls related to mental health emergencies. The purpose of this report is to illustrate the value of additional targeted training for EMDs that enables them to more effectively assist callers struggling with mental illness or suicidal thoughts. We review a 9-1-1 call in which an EMD utilized specific strategies and language learned during a 3-day emergency mental health dispatch (EMHD) training course to assist a middle-aged male who was expressing suicidal intent with a firearm. Key principles and phrasing from the training were used successfully by the EMD to dissuade the caller from self-harm, and he was ultimately safely met by first responders on scene and transported for care. We also share post-call recollections and reactions from the EMD to demonstrate how in addition to reducing risks for callers and their families, EMHD training has the potential to reduce on-scene risks for field responders and may increase confidence and mitigate negative stress responses in EMDs. Emergency medical services systems in the United States should continue to explore enhanced training and protocols to improve care for 9-1-1 callers experiencing mental health crises.

Quality and safety in prehospital airway management – retrospective analysis of 18,000 cases from an air rescue database in Germany

BackgroundPrehospital airway management remains crucial with regard to the quality and safety of emergency medical service (EMS) systems worldwide. In 2007, the benchmark study by Timmermann et al. hit the German EMS community hard by revealing a significant rate of undetected oesophageal intubations leading to an often-fatal outcome. Since then, much attention has been given to guideline development and training. This study evaluated the incidence and special circumstances of tube misplacement as an adverse peri-intubation event from a Helicopter Emergency Medical Services perspective.MethodsThis was a retrospective analysis of a German helicopter-based EMS database from January 1, 2012, to December 31, 2020. All registered patients were included in the primary analysis. The results were analysed using SPSS 27.0.1.0.ResultsOut of 227,459 emergency medical responses overall, a total of 18,087 (8.0%) involved invasive airway management. In 8141 (45.0%) of these patients, airway management devices were used by ground-based EMS staff, with an intubation rate of 96.6% (n = 7861), and alternative airways were used in 3.2% (n = 285). Overall, the rate of endotracheal intubation success was 94.7%, while adverse events in the form of tube misplacement were present in 5.3%, with a 1.2% rate of undetected oesophageal intubation. Overall tube misplacement and undetected oesophageal intubation occurred more often after intubation was carried out by paramedics (10.4% and 3.6%, respectively). In view of special circumstances, those errors occurred more often in the presence of trauma or cardiopulmonary resuscitation, with rates of 5.6% and 6.4%, respectively. Difficult airways with a Cormack 4 status were present in 2.1% (n = 213) of HEMS patients, accompanied by three or more intubation attempts in 5.2% (n = 11).ConclusionsPrehospital airway management success has improved significantly in recent years. However, adverse peri-intubation events such as undetected oesophageal intubation remain a persistent threat to patient safety.Trial registrationThe study was registered in the German Register for Clinical Studies (number DRKS00028068).

South African palliative care provider perspectives on emergency medical services in palliative situations

IntroductionDue to the frequent intersection of Emergency Medical Services (EMS) with palliative situations and the increasing global need for palliative care, there has been increased recognition of the need for palliative care integration with EMS. However, EMS and palliative care systems remain segregated in many Low-to-Middle Income Country contexts, as in South Africa (SA). The aim of this study was to gather perspectives of palliative care providers in SA concerning EMS in palliative situations. MethodsA qualitative design employing individual semi-structured interviews was implemented. Ten interviews with experienced doctors and nurses holding post-graduate palliative medicine qualifications were conducted. Verbatim transcriptions of interviews were subjected to content analysis with an inductive-dominant approach to develop codes and categories. ResultsFour categories were developed: (1) Disposition towards EMS, (2) Perceived EMS challenges, (3) Positive EMS impact across patients’ palliative care journeys and (4) Methods of EMS and palliative care system integration. Participants maintained an overall positive view of EMS and palliative care integration, noting the beneficial impact of EMS and suggesting various methods of integration, while also highlighting challenges and concerns. ConclusionEMS and palliative care integration would be mutually beneficial to both systems while benefiting patient well-being and the broader healthcare system. Potentially low-cost, high-impact interventions suggested by participants, such as palliative care cards for patients and enhancing EMS and palliative care system communication, represent efficacious and judicious use of limited resources within the SA context. Pilot studies investigating these suggestions should be conducted.

"You might be nice, but where you take me, they're not gonna be": Preferences for field-based post-overdose interventions.

Emergency medical services (EMS) systems are piloting interventions to respond to overdoses with additional services such as leave-behind naloxone and medication for opioid use disorder, but little is known about the perspectives of people who use drugs (PWUD) on these interventions being delivered by EMS during an overdose response. The Consolidated Framework for Implementation Research guided the development of data collection tools, the analytic strategy and the organisation of results. A community engaged method was used which included both academically trained researchers and community trained researchers who are also PWUD. This study used semi-structured interviews to gather data from 13 PWUD in King County, Washington in June 2022. Data were analysed using thematic analysis. The people interviewed for this study viewed EMS distribution of leave-behind naloxone and field-based buprenorphine favourably. They viewed EMS facilitation of hepatitis C virus and HIV testing in the field less favourably and were concerned about stigmas associated with those results. Additional themes emerged regarding: the need for different approaches to post-overdose care; the need for new services, including post-overdose trauma counselling and an alternative destination to the emergency department; and the harms of law enforcement presence at overdose responses. This study found strong support for leave-behind naloxone and field-initiated buprenorphine. Further training for EMS should include trauma-informed care and strategies to address burnout and increase compassion. Alternatives to the emergency department as a post-overdose destination are needed. These strategies should be considered by jurisdictions revising overdose response protocols.

Telemedical Direction to Optimize Resource Utilization in a Rural Emergency Medical Services System.

Telemedicine remains an underused tool in rural emergency medical servces (EMS) systems. Rural emergency medical technicians (EMT) and paramedics cite concerns that telemedicine could increase Advanced Life Support (ALS) transports, extend on-scene times, and face challenges related to connectivity as barriers to implementation. Our aim in this project was to implement a telemedicine system in a rural EMS setting and assess the impact of telemedicine on EMS management of patients with chest pain while evaluating some of the perceived barriers. This study was a mixed-methods, retrospective review of quality assurance data collected prior to and after implementation of a telemedicine program targeting patients with chest pain. We compared quantitative data from the 12-month pre-implementation phase to data from 15 months post-implementation. Patients were included if they had a chief complaint of chest pain or a 12-lead electrocardiogram had been obtained. The primary outcome was the rate of ALS transport before and after program implementation. Secondary outcomes included EMS call response times and EMS agency performance on quality improvement benchmarks. Qualitative data were also collected after each telemedicine encounter to evaluate paramedic/EMT and EMS physician perception of call quality. The telemedicine pilot project was implemented in September 2020. Overall, there were 58 successful encounters. For this analysis, we included 38 patients in both the pre-implementation period (September 9, 2019-September 10, 2020) and the post-implementation period (September 11, 2020-December 5, 2021). Among this population, the ALS transport rate was 42% before and 45% after implementation (odds ratio 1.11; 95% confidence interval 0.45-2.76). The EMS median out-of-service times were 47 minutes before, and 33 minutes after (P = 0.07). Overall, 64% of paramedics/EMTs and 89% of EMS physicians rated the telemedicine call quality as "good." In this rural EMS system, a telehealth platform was successfully used to connect paramedics/EMTs to board-certified EMS physicians over a 15-month period. Telemedicine use did not alter rates of ALS transports and did not increase on-scene time. The majority of paramedics/EMTs and EMS physicians rated the quality of the telemedicine connection as "good."

Challenges to Integrating Portable Magnetic Resonance Imaging Systems in Emergency Medical Service Ambulances for Stroke Care

This qualitative study explores the barriers to incorporating portable MRI devices in ambulances, enabling effective patient triage and potentially reducing time to thrombolytic treatment for stroke. Using a digital twin of the patient handling process, semi-structured interviews were conducted with 11 paramedics and 7 neurologists from an emergency medical services system and a tertiary stroke care center. Thematic analysis of interview transcripts, guided by the Systems Engineering Initiative for Patient Safety framework, revealed key barriers: the need for specialized MRI operation skills, complex patient handling procedures, limited space, and the necessity for training and policy development. The study proposes solutions to address these challenges, aiming to facilitate the implementation of ambulance-based MRI systems for expedited stroke care. The findings contribute to understanding the factors influencing the adoption of advanced imaging technology in pre-hospital settings, ultimately improving patient outcomes by minimizing delays in stroke treatment.

Emergency medical services infrastructure development and operations in low- and middle-income countries: Community first responder–driven (Tier-1) emergency medical services systems

Low- and middle-income countries face unique challenges in delivering prehospital emergency care, often requiring context-appropriate emergency medical services development focused on community-driven solutions (tier 1 systems). Replicating high-income country tier 2 systems in low- and middle-income countries is not financially feasible in resource-limited settings. Instead, tier 1 systems composed of trained layperson first responders use locally available vehicles and involve local communities and stakeholders in their design and implementation to address specific local needs and emergencies. Community engagement is crucial for establishing sustainable and inclusive emergency medical services systems. This article focuses on the development and operation of tier 1 systems in low- and middle-income countries, covering technology integration, local appropriateness and co-operation, training curricula, trainee recruitment and selection, volunteer incentivization, monitoring and evaluation, and coordination with tier 2 systems. Layperson first responder programs are essential to address the global injury burden that disproportionately affects low- and middle-income countries and to evolve into, or coordinate with, tier 2 systems in resource-limited settings, but this requires community involvement to increase local ownership, drive sustainable solutions, and respect local values and cultures.

Drug Misuse Among Pediatric Patients: Encounters in the Prehospital Field.

Few data describing prehospital pediatric substance misuse exist. The objective of this study was to characterize substance misuse in North Carolina pediatric patients receiving emergency medical services (EMS) care. We conducted a retrospective cross-sectional study of patients aged < 16 years transported by EMS for substance misuse. Data were obtained from a statewide repository including patients treated for confirmed or suspected misuse of marijuana, alcohol, benzodiazepines, opioids, stimulants, acetaminophen, antidepressants, or other drugs. Of 45,855 EMS encounters, 448 patients misused drugs. Most patients were female (56.7%), White (50.9%), adolescent (73.8%), and resided in Central North Carolina (54.0%). A plurality of cases was rural (46.2%), followed by urban (27.9%) and regional city/suburban counties (25.7%). Calls most often originated in residential locations (68.5%). Drugs identified during EMS calls included alcohol (24.2%), marijuana (24.2%), benzodiazepines (8.8%), antidepressants (8.8%), stimulants (6.8%), opioids (5.9%), and other medications (17.6%). Motivations for drug use were recreational (58.4%), self-harm (24.6%), and accidental (17.0%). Due to insufficient data documentation, one EMS system was removed from analysis. Additionally, misclassification of type of drug or intention of drug use is possible due to the use of free-text patient narratives. EMS responded to a vast variety of drug misuse among pediatric patients including prescription medications, alcohol, marijuana, and illicit drugs. Accidental ingestions occurred exclusively in infant/preschool ages and intent for recreation or self-harm primarily occurred in adolescents. By increasing awareness of the more common pediatric patient characteristics associated with the type and reason for drug use, EMS agencies can improve pediatric readiness among prehospital clinicians.

The impact of using time critical intervention-based dispatch thresholds on lowering lights and siren use to EMS 911 incidents.

Emergency Medical Services (EMS)has historically utilized lights and sirens (L&S) to respond to 911 incidents. L&S are used in 86% of scene responses nationally; however, time critical interventions (TCIs) occur in less than 7% of these incidents. Responses with L&S are associated with increased risk of crashes and injuries. Our objective was to determine the impact of TCI-based dispatch thresholds on L&S use, dispatch accuracy, and response times. We performed a before-after retrospective evaluation of TCI-based dispatch methodology at a suburban EMS system. We categorized all EMS interventions as TCI or not, and we determined a TCI threshold above which we would use L&S. We then assigned response priorities to each call nature based on the proportion of TCIs within them. We compared historical results with those from the 6 months following implementation in terms of L&S use, dispatch accuracy, and response times. There were 13,879 responses in the "before" group and 14,117 in the "after" group. The rate of L&S use decreased from 56.2% in the before group to 27.6% in the after group, while TCIs were performed in 6.9% of responses in the before group and 7.6% in the after group. Accuracy increased from 48.8% to 75.1% and median response time increased by 0.1 min from 8.3 to 8.4 min. Using TCI-based dispatch thresholds, we decreased L&S use and increased accuracy with minimal increased response time. Our results support the use of this methodology to determine EMS response modes.

The current state of emergency medical services in South Africa: A review

Emergency medical services (EMS) are a vital component of the health system and provide pre-hospital emergency care and specialised transport for patients requiring access to health facilities, thereby contributing to universal health coverage and improving health outcomes. Evidence regarding the current state of EMS within South Africa to fulfil this role is lacking and was the motivation for this review. Our objective was to describe the current state of EMS in South Africa. A literature search was conducted using keywords, BOOLEAN operating terms, and eligibility criteria on Sabinet, EBSCOhost, Google Scholar, ProQuest, Medline, PubMed, and ScienceDirect databases to find articles related to the components of the EMS system in South Africa. The articles were critically assessed, and six themes emerged: leadership and governance; resources; preparedness (knowledge, attitude, and practices) of the emergency care provider; health and safety; training; and communications. Challenges were found in all themes at a provincial EMS level despite improvements in legislation, leadership, and governance from the National Department of Health. These themes demonstrate that all components in the EMS system are not functioning optimally and may be affecting its contribution to improving universal health coverage and health outcomes. The current state of EMS appears to be constrained and requires greater leadership and governance from the Provincial Departments of Health to improve poorly functioning components of the EMS system.

Clinical phenotypes and short-term outcomes based on prehospital point-of-care testing and on-scene vital signs

Emergency medical services (EMSs) face critical situations that require patient risk classification based on analytical and vital signs. We aimed to establish clustering-derived phenotypes based on prehospital analytical and vital signs that allow risk stratification. This was a prospective, multicenter, EMS-delivered, ambulance-based cohort study considering six advanced life support units, 38 basic life support units, and four tertiary hospitals in Spain. Adults with unselected acute diseases managed by the EMS and evacuated with discharge priority to emergency departments were considered between January 1, 2020, and June 30, 2023. Prehospital point-of-care testing and on-scene vital signs were used for the unsupervised machine learning method (clustering) to determine the phenotypes. Then phenotypes were compared with the primary outcome (cumulative mortality (all-cause) at 2, 7, and 30 days). A total of 7909 patients were included. The median (IQR) age was 64 (51–80) years, 41% were women, and 26% were living in rural areas. Three clusters were identified: alpha 16.2% (1281 patients), beta 28.8% (2279), and gamma 55% (4349). The mortality rates for alpha, beta and gamma at 2 days were 18.6%, 4.1%, and 0.8%, respectively; at 7 days, were 24.7%, 6.2%, and 1.7%; and at 30 days, were 33%, 10.2%, and 3.2%, respectively. Based on standard vital signs and blood test biomarkers in the prehospital scenario, three clusters were identified: alpha (high-risk), beta and gamma (medium- and low-risk, respectively). This permits the EMS system to quickly identify patients who are potentially compromised and to proactively implement the necessary interventions.

Italy's Post-COVID-19 Stroke Network: Has It Returned to Pre-Pandemic Standards?

The COVID-19 pandemic strongly transformed the healthcare system in the Lombardy region (Italy), forcing a rapid reorganization of hospital structures. The emergency medical service (EMS) system and emergency departments (EDs) were among the most affected departments. Several studies have shown a change in the epidemiology of time-dependent pathologies, such as stroke, during the pandemic's peak. However, there is little scientific evidence regarding the interpandemic phase. The regional register for ED accesses (EUOL) was analyzed, taking into consideration all accesses for stroke and stroke-like syndromes during the years 2019, 2020, and 2021. The analysis shows a significant difference in the average number of diagnoses per month [2092 vs. 1815 vs. 2015, respectively (p < 0.05)] and an increase in the percentage of transports carried out by EMS vehicles to EDs [17% vs. 25% vs. 22%, respectively (p < 0.05)]. The length of stay (LOS) increased for both discharged patients (9.0 vs. 10.1 vs. 11.2 h, respectively; p < 0.005) and hospitalized patients (7.5 vs. 9.7 vs. 10.6 h, respectively; p < 0.005). During the COVID-19 pandemic, the overall number of stroke diagnoses decreased, while the percentage of patients transported to EDs by EMS vehicles increased. Furthermore, an increased processing time in EDs was highlighted.

Navigating urban challenges: Quantifying emergency service accessibility and robustness amid meteorological disasters

The frequent occurrence of meteorological disasters presents a significant challenge to the effective functioning of urban public services. This paper seeks to assess the response capacity of urban emergency services during such disasters by integrating perspectives on accessibility and robustness. Through a case study on emergency medical services (EMS), we develop a framework for evaluating the EMS system in downtown Shanghai under the scenario of typhoon In-Fa. This framework encompasses the calculation of both the accessible area of ambulance vehicles and the accessibility to each resident address. Our findings indicate that under normal conditions, the majority of residential areas in downtown Shanghai can access nearby medical services within 10 min. However, accessibility decreases by 28.85 % and 43.83 % under moderate and severe flooding conditions, respectively. Furthermore, by analyzing changes in the robustness of the service supply network, we identify warning and critical points, offering valuable insights for the formulation of disaster warning and response strategies. This study integrates system-level robustness and address-level accessibility to establish a comprehensive framework for evaluating urban emergency service performance under meteorological disaster scenarios. The proposed approach holds promise for evaluating other types of public services by adapting the framework to account for specific supply and demand dynamics.

Improving urban emergency medical service systems through brownfield transformation in Huangshi, China

A comprehensive emergency medical service (EMS) system significantly enhances a city’s capacity to prevent and mitigate disasters. Using Huangshi as a case study, this research evaluated the service radium coverage rate of the current EMS system by examining its transport capacity, population density, and prevalence rate, finding it to be only 61.49% with an inefficient spatial layout. To address this, we proposed transforming urban brownfields into EMS parks. By selecting the most suitable brownfields based on capacity and service radius, we increased the coverage rate to 90.21%. We introduced a new "consultation-referral" model, where existing EMS facilities serve as pre-diagnosis and triage centers, and the urban brownfield EMS parks function as isolation and centralized treatment centers. GIS network analysis confirmed the feasibility, showing all transit times to be under 30 min. The methodology outlined in this study—comprising "demand assessment, supply optimization, and feasibility verification"—not only strengthens the city’s EMS system but also facilitates the renewal of urban brownfields. This approach can serve as a valuable reference for enhancing EMS systems in other cities.

Barriers to integrating portable Magnetic Resonance Imaging systems in emergency medical service ambulances for stroke care

This study examines the barriers to integrating portable Magnetic Resonance Imaging (MRI) systems into ambulance services to enable effective triaging of patients to the appropriate hospitals for timely stroke care and potentially reduce door-to-needle time for thrombolytic administration. The study employs a qualitative methodology using a digital twin of the patient handling process developed and demonstrated through semi-structured interviews with 18 participants, including 11 paramedics from an Emergency Medical Services system and seven neurologists from a tertiary stroke care centre. The interview transcripts were thematically analysed to determine the barriers based on the Systems Engineering Initiative for Patient Safety framework. Key barriers include the need for MRI operation skills, procedural complexities in patient handling, space constraints, and the need for training and policy development. Potential solutions are suggested to mitigate these barriers. The findings can facilitate implementing MRI systems in ambulances to expedite stroke treatment.

Perceived Versus Actual Time of Prehospital Intubation by Paramedics.

Situational awareness is essential during emergent procedures such as endotracheal intubation. Previous studies suggest that time distortion can occur during intubation. However, only in-hospital intubations performed by physicians have been studied. We aimed to determine whether time distortion affected paramedics performing intubation by examining the perceived vs actual total laryngoscopy time, defined as time elapsed from the laryngoscope blade entering the mouth until the endotracheal tube balloon passes the vocal cords. For this retrospective study we collected prehospital intubation data from a suburban, fire department-based emergency medical services (EMS) system from January 5, 2021-May 21, 2022. The perceived total laryngoscopy time was queried as a part of the electronic health record. Video laryngoscopy recordings were reviewed by a panel of experts to determine the actual time. Patients >18 years old who underwent intubation by paramedics with video laryngoscopy were included for analysis. The primary outcome was the difference between actual and perceived total laryngoscopy time. Secondary analysis examined the relationship between high time distortion, defined as the highest quartile of the primary outcome, and patient age, paramedic years of experience, perceived presence of difficult anatomy, excess secretions, use of rapid sequence intubation, and multiple intubation attempts. We conducted descriptive analysis followed by logistic regression analysis, chi-square tests, and Fisher exact tests when appropriate. A total of 122 intubations were collected for analysis, and 10 were excluded due to lack of video recording. Final analysis included 112 intubations. Mean actual laryngoscopy time was 50.0 seconds (s) (95% confidence interval [CI] 43.7-56.3). Mean perceived laryngoscopy time was 27.8 s (95% CI 24.7-31.0). The median difference between actual and perceived time was 18 s (interquartile range 6-30). We calculated high time distortion as having a difference greater than 30 s between actual and perceived laryngoscopy time. None of the secondary variables had statistically significant associations with high time distortion. Overall, we show that the paramedic's perception of total laryngoscopy time is significantly underestimated even when accounting for paramedic experience and perceived airway difficulty. This study suggests that time distortion may lead to an unrecognized prolonged procedure time. Limitations include use of a convenience sample, small sample size, and potential uncollected confounding variables.

Comparison of pre-hospital management of out-of-hospital cardiac arrest and its outcomes between the COVID-19 and pre-COVID-19 periods

Out-of-hospital cardiac arrest (OHCA) is a time-sensitive medical emergency that needs immediate interventions. COVID-19 affected the performance of the emergency medical service (EMS) system in pre-hospital care, including the management of cardiac arrest. This study aimed to identify the impact of the COVID-19 pandemic on pre-hospital management of out-of-hospital cardiac arrest and its outcome in Qom City, Iran. In this descriptive-analytical study, the data were collected from the electronic registration system of the EMS center in Qom, Iran. All OHCA patients who received resuscitation during COVID-19 and before COVID-19 were enrolled in the study. Data consisted of the characteristics of OHCA patients, EMS interventions and response times, and the outcome of OHCA. A P-value of <0.05 was deemed statistically significant. 630 OHCA patients in the COVID-19 period and 524 OHCA patients in the pre-COVID-19 period were included in the study. Endotracheal intubation and defibrillation were done more in the COVID-19 period than in the pre-COVID-19 period (50.2 % vs. 17 %, p<0.001 %, and 40.1 % vs. 22.5 %, p < 0.001, respectively). The EMS response time was longer during the COVID-19 pandemic (9.1 ± 3.9 min vs. 7.6 ± 1.4 min, p < 0.001). The rate of pre-hospital return of spontaneous circulation (ROSC) was lower in the COVID-19 period (15.6 % vs. 8.4 %, p < 0.001). According to univariate analysis, ROSC was predicted by COVID-19 (p < 0.001). However, COVID-19 was not the statistically significant independent predictor after multivariate analysis (p < 0.67). The COVID-19 pandemic period influenced OHCA and ROSC. Also, it affected pre-hospital management in the OHCA situation. The negative impact of COVID-19 on the EMS response reflected the need to know and remove barriers to managing crises such as COVID-19.

A Process Algebraic Approach to Predict and Control Uncertainty in Smart IoT Systems for Smart Cities Based on Permissible Probabilistic Equivalence.

Process algebra is one of the most suitable formal methods to model smart IoT systems for smart cities. Each IoT in the systems can be modeled as a process in algebra. In addition, the nondeterministic behavior of the systems can be predicted by defining probabilities on the choice operations in some algebra, such as PALOMA and PACSR. However, there are no practical mechanisms in algebra either to measure or control uncertainty caused by the nondeterministic behavior in terms of satisfiability of the system requirements. In our previous research, to overcome the limitation, a new process algebra called dTP-Calculus was presented to verify probabilistically the safety and security requirements of smart IoT systems: the nondeterministic behavior of the systems was defined and controlled by the static and dynamic probabilities. However, the approach required a strong assumption to handle the unsatisfied probabilistic requirements: enforcing an optimally arbitrary level of high-performance probability from the continuous range of the probability domain. In the paper, the assumption from the previous research is eliminated by defining the levels of probability from the discrete domain based on the notion of Permissible Process and System Equivalences so that satisfiability is incrementally enforced by both Permissible Process Enhancement in the process level and Permissible System Enhancement in the system level. In this way, the unsatisfied probabilistic requirements can be incrementally enforced with better-performing probabilities in the discrete steps until the final decision for satisfiability can be made. The SAVE tool suite has been developed on the ADOxx meta-modeling platform to demonstrate the effectiveness of the approach with a smart EMS (emergency medical service) system example, which is one of the most practical examples for smart cities. SAVE showed that the approach is very applicable to specify, analyze, verify, and especially, predict and control uncertainty or risks caused by the nondeterministic behavior of smart IoT systems. The approach based on dTP-Calculus and SAVE may be considered one of the most suitable formal methods and tools to model smart IoT systems for smart cities.

Impact of Bystander Cardiopulmonary Resuscitation on Out-of-Hospital Cardiac Arrest Outcome in Vietnam.

Patients experiencing an out-of-hospital cardiac arrest (OHCA) frequently do not receive bystander cardiopulmonary resuscitation (CPR), especially in low- and middle-income countries (LMIC). In this study we sought to determine the prevalence of OHCA patients in Vietnam who received bystander CPR and its effects on survival outcomes. We performed a multicenter, retrospective observational study of patients (≥18years) presenting with OHCA at three major hospitals in an LMIC from February 2014-December 2018. We collected data on the hospital and patient characteristics, the cardiac arrest events, the emergency medical services (EMS) system, the therapy methods, and the outcomes and compared these data, before and after pairwise 1:1 propensity score matching, between patients who received bystander CPR and those who did not. Upon admission, we assessed factors associated with good neurological survival at hospital discharge in univariable and multivariable logistic models. Of 521 patients, 388 (74.5%) were men, and the mean age was 56.7years (SD 17.3). Although most cardiac arrests (68.7%, 358/521) occurred at home and 78.8% (410/520) were witnessed, a low proportion (22.1%, 115/521) of these patients received bystander CPR. Only half of the patients were brought by EMS (8.1%, 42/521) or private ambulance (42.8%, 223/521), 50.8% (133/262) of whom had resuscitation attempts. Before matching, there was a significant difference in good neurological survival between patients who received bystander CPR (12.2%, 14/115) and patients who did not (4.7%, 19/406; P < .001). After matching, good neurological survival was absent in all OHCA patients who did not receive CPR from a bystander. The multivariable analysis showed that bystander CPR (adjusted odds ratio: 3.624; 95% confidence interval 1.629-8.063) was an independent predictor of good neurological survival. In our study, only 22.1% of total OHCA patients received bystander CPR, which contributed significantly to a low rate of good neurological survival in Vietnam. To improve the chances of survival with good neurological functions of OHCA patients, more people should be trained to perform bystander CPR and teach others as well. A standard program for emergency first-aid training is necessary for this purpose.