Prehospital interventions and outcomes in traumatic cardiac arrest: a population-based cohort study using the Danish Helicopter Emergency Medical Services data.

BACKGROUND AND IMPORTANCE: Traumatic cardiac arrest is associated with poor prognosis, and timely evidence-based treatment is paramount for increasing survival rates. Physician-staffed helicopter emergency medical service use in major trauma has demonstrated improved outcomes. However, the sparsity of data highlights the necessity for a comprehensive understanding of the epidemiology of traumatic cardiac arrest. OBJECTIVES: The primary objective of the present study was to evaluate survival and return of spontaneous circulation (ROSC) and to investigate the characteristics of patients with traumatic cardiac arrest assessed by the Danish HEMS. DESIGN: This was a population-based cohort study based on data from the Danish helicopter emergency medical service database. SETTINGS AND PARTICIPANTS: The study included all patients assessed by the Danish helicopter emergency medical services between 2016 and 2021. OUTCOME MEASURES AND ANALYSIS: Data were analysed using descriptive statistics, non-parametric testing and logistic regression analyses. Descriptive analysis of prehospital interventions included cardiopulmonary resuscitation, defibrillation, airway management, administration of blood products, and thoracic decompression. The primary outcome was 30-day survival, and the key secondary outcome was prehospital ROSC. MAIN RESULTS: A total of 223 patients with TCA were included. The median age was 54 years (IQR 34-68), and the majority were males. Overall, 23% of patients achieved prehospital ROSC, and the 30-day survival rate was 4%. Factors associated with an increased likelihood of ROSC were an initial shockable cardiac rhythm, odds ratio (OR) of 3.78 (95% CI 1.33-11.00) and endotracheal intubation, OR 7.10 (95% CI 2.55-22.85). CONCLUSION: This study highlights the low survival rates observed among patients with traumatic cardiac arrest assessed by helicopter emergency medical services. The findings support the positive impact of an initial shockable cardiac rhythm and endotracheal intubation in improving the likelihood of ROSC. The study contributes to the limited literature on traumatic cardiac arrests assessed by physician-staffed helicopter emergency services. Finally, the findings emphasise the need for further research to understand and improve outcomes in this subgroup of cardiac arrest.

An explorative study of nurses' perception of turnover and retention.

INTRODUCTION: High nurse turnover at hospitals is a major societal problem. Knowledge of how to decrease the turnover rate is important. The aim of this study was to explore nurses' perception of nurse turnover and retention. METHODS: An explorative study was designed with table-top simulations involving newly graduated nurses, experienced nurses and nurse supervisors in internal medicine departments. The simulations were audio-recorded and transcribed. The participants took notes, which were transcribed. The citations were sorted into subthemes and themes by use of inductive content analysis. RESULTS: Fifteen workshops involving a total of 43 nurses were conducted. Four overarching themes were identified: core clinical competence, professionalism, organisation and culture. The new nurses focused on development and evaluation of core clinical competences to be able to provide safe patient care. The experienced nurses favoured influence on own work and a plan for continuous professional development. The importance of a good learning culture and of collegial and social factors was mentioned by both groups of nurses. CONCLUSIONS: The table-top simulations with newly graduated nurses, senior nurses and nurses responsible for education provided valuable insights into the nurses´ perspectives of determinants of nurse turnover and retention in internal medicine wards. FUNDING: None. TRIAL REGISTRATION: Not relevant.

Helicopter emergency medical services missions to islands and the mainland during a 3-year period in Denmark: a population-based study on patient and sociodemographic characteristics, comorbidity, and use of healthcare services.

BACKGROUND: The Danish Helicopter Emergency Medical Services (HEMS) is part of the Danish Emergency Medical Services System serving 5.7 million citizens with 1% living on islands not connected to the mainland by road. HEMS is dispatched based on pre-defined criteria including severity and urgency, and moreover to islands for less urgent cases, when rapid transport to further care is needed. The study aim was to characterize patient and sociodemographic factors, comorbidity and use of healthcare services for patients with HEMS missions to islands versus mainland. METHODS: Descriptive study of data from the HEMS database in a three-year period from 1 October 2014 to 30 September 2017. All missions in which a patient was either treated on scene or transported by HEMS were included. RESULTS: Of 5776 included HEMS missions, 1023 (17.7%) were island missions. In total, 90.2% of island missions resulted in patient transport by HEMS compared with 62.1% of missions to the mainland. Disease severity was serious or life-threatening in 34.7% of missions to islands compared with 65.1% of missions to mainland and less interventions were performed by HEMS on island missions. The disease pattern differed with more "Other diseases" registered on islands compared with the mainland where cardiovascular diseases and trauma were the leading causes of contact. Patients from islands were older than patients from the mainland. Sociodemographic characteristics varied between inhabiting island patients and mainland patients: more island patients lived alone, less were employed, more were retired, and more had low income. In addition, residing island patients had to a higher extend severe comorbidity and more contacts to general practitioners and hospitals compared with the mainland patients. CONCLUSIONS: HEMS missions to islands count for 17.7% of HEMS missions and 90.2% of island missions result in patient transport. The island patients encountered by HEMS are less severely diseased or injured and interventions are less frequently performed. Residing island patients are older than mainland patients and have lower socioeconomic position, more comorbidities and a higher use of health care services. Whether these socio-economic differences result in longer hospital stay or higher mortality is still to be investigated.

Description of call handling in emergency medical dispatch centres in Scandinavia: recognition of out-of-hospital cardiac arrests and dispatcher-assisted CPR.

BACKGROUND: The European resuscitation council have highlighted emergency medical dispatch centres as an important key player for early recognition of Out-of-Hospital Cardiac Arrest (OHCA) and in providing dispatcher assisted cardiopulmonary resuscitation (CPR) before arrival of emergency medical services. Early recognition is associated with increased bystander CPR and improved survival rates. The aim of this study is to describe OHCA call handling in emergency medical dispatch centres in Copenhagen (Denmark), Stockholm (Sweden) and Oslo (Norway) with focus on sensitivity of recognition of OHCA, provision of dispatcher-assisted CPR and time intervals when CPR is initiated during the emergency call (NO-CPRprior), and to describe OHCA call handling when CPR is initiated prior to the emergency call (CPRprior). METHODS: Baseline data of consecutive OHCA eligible for inclusion starting January 1st 2016 were collected from respective cardiac arrest registries. A template based on the Cardiac Arrest Registry to Enhance Survival definition catalogue was used to extract data from respective cardiac arrest registries and from corresponding audio files from emergency medical dispatch centres. Cases were divided in two groups: NO-CPRprior and CPRprior and data collection continued until 200 cases were collected in the NO-CPRprior-group. RESULTS: NO-CPRprior OHCA was recognised in 71% of the calls in Copenhagen, 83% in Stockholm, and 96% in Oslo. Abnormal breathing was addressed in 34, 7 and 98% of cases and CPR instructions were started in 50, 60, and 80%, respectively. Median time (mm:ss) to first chest compression was 02:35 (Copenhagen), 03:50 (Stockholm) and 02:58 (Oslo). Assessment of CPR quality was performed in 80, 74, and 74% of the cases. CPRprior comprised 71 cases in Copenhagen, 9 in Stockholm, and 38 in Oslo. Dispatchers still started CPR instructions in 41, 22, and 40% of the calls, respectively and provided quality assessment in 71, 100, and 80% in these respective instances. CONCLUSIONS: We observed variations in OHCA recognition in 71-96% and dispatcher assisted-CPR were provided in 50-80% in NO-CPRprior calls. In cases where CPR was initiated prior to emergency calls, dispatchers were less likely to start CPR instructions but provided quality assessments during instructions.

Medical dispatchers' perception of the interaction with the caller during emergency calls - a qualitative study.

BACKGROUND: Medical dispatching is a highly complex procedure and has an impact upon patient outcome. It includes call-taking and triage, prioritization of resources and the provision of guidance and instructions to callers. Whilst emergency medical dispatchers play a key role in the process, their perception of the process is rarely reported. We explored medical dispatchers' perception of the interaction with the caller during emergency calls. Secondly, we aimed to develop a model for emergency call handling based on these findings. METHODS: To provide an in-depth understanding of the dispatching process, an explorative qualitative interview study was designed. A grounded theory design and thematic analysis were applied. RESULTS: A total of 5 paramedics and 6 registered nurses were interviewed. The emerging themes derived from dispatchers' perception of the emergency call process were related to both the callers and the medical dispatchers themselves, from which four and three themes were identified, respectively. Dispatchers reported that for callers, the motive for calling, the situation, the perception and presentation of the problem was influencing factors. For the dispatchers the expertise, teamwork and organization influenced the process. Based on the medical dispatchers´ perception, a model of the workflow and interaction between the caller and the dispatcher was developed based on themes related to the caller and the dispatcher. CONCLUSIONS: According to medical dispatchers, the callers seem to lack knowledge about best utilization of the emergency number and the medical dispatching process, which can be improved by public awareness campaigns and incorporating information into first aid courses. For medical dispatchers the most potent modifiable factors were based upon the continuous professional development of the medical dispatchers and the system that supports them. The model of call handling underlines the complexity of medical dispatching that embraces the context of the call beyond clinical presentation of the problem.

Data concerning the Copenhagen tool: A research tool for evaluation of basic life Support educational interventions.

The data presented in this article are supplementary data related to the research article entitled "The Copenhagen Tool: A research tool for evaluation of BLS educational interventions" (Jensen et al., 2019). We present the following supplementary materials and data: 1) a standardized scenario used to introduce the test for gathering data on internal structure and additional response process; 2) test sheets used for rating test participant via video recordings; 3) interview-guide for collecting additional response process data; 4) items deemed relevant but not essential for laypersons, first responders and health personnel in the modified Delphi consensus process; 5) inter-rater reliability values for raters using the essential items of the tool to evaluate test participants via video recordings; 6) main themes from coding interviews with raters; 7) comparison of rater results and manikin software output.

The Copenhagen Tool a research tool for evaluation of basic life support educational interventions.

INTRODUCTION: Over the past decades, major changes have been made in basic life support (BLS) guidelines and manikin technology. The aim of this study was to develop a BLS evaluation tool based on international expert consensus and contemporary validation to enable more valid comparison of research on BLS educational interventions. METHODS: A modern method for collecting validation evidence based on Messick's framework was used. The framework consists of five domains of evidence: content, response process, internal structure, relations with other variables, and consequences. The research tool was developed by collecting content evidence based on international consensus from an expert panel; a modified Delphi process decided items essential for the tool. Agreement was defined as identical ratings by 70% of the experts. RESULTS: The expert panel established consensus on a three-levelled score depending on expected response level: laypersons, first responders, and health care personnel. Three Delphi rounds with 13 experts resulted in 16 "essential" items for laypersons, 21 for first responders, and 22 for health care personnel. This, together with a checklist for planning and reporting educational interventional studies within BLS, serves as an example to be used for researchers. CONCLUSIONS: An expert panel agreed on a three-levelled score to assess BLS skills and the included items. Expert panel consensus concluded that the tool serves its purpose and can act to guide improved research comparison on BLS educational interventions.

Characteristics of patients treated by the Danish Helicopter Emergency Medical Service from 2014-2018: a nationwide population-based study.

BACKGROUND: A national Helicopter Emergency Medical Service (HEMS) was introduced in Denmark in 2014 to ensure the availability of physician-led critical care for all patients regardless of location. Appropriate dispatch of HEMS is known to be complex, and resource utilisation is a highly relevant topic. Population-based studies on patient characteristics are fundamental when evaluating and optimising a system. The aim of this study was to describe the patient population treated by the Danish HEMS in terms of demographics, pre-hospital diagnostics, severity of illness or injury, and the critical care interventions performed. METHOD: The study is a retrospective nationwide population-based study based on data gathered from the Danish HEMS database. We included primary missions resulting in a patient encounter registered between October 1st 2014 and April 30th 2018. RESULTS: Of 13.391 dispatches registered in the study period we included 7133 (53%) primary missions with patient encounter: 4639 patients were air lifted to hospital, 174 patients were escorted to hospital by the HEMS physician in an ambulance, and in 2320 cases HEMS assisted the ground crew on scene but did not escort the patient to hospital. Patient age ranged from 0-99 years and 64% of the population were men. The median age was 60 years. The main diagnostic groups were cardio-vascular emergencies (41%), trauma (23%) and neurological emergencies (16%). In 61% of the cases, the patient was critically ill/injured corresponding to a NACA (National Advisory Committee for Aeronautics) score between 4 and 7 (both included). In more than one third of the missions a critical care intervention was performed. Ultrasound examination and endo-tracheal intubation were the critical care interventions most frequently performed (21% and 20%, respectively). CONCLUSION: The national Danish HEMS primarily attends severely ill or injured patients and often perform critical care interventions. In addition, the Danish HEMS provides rapid transport to highly specialised treatment for patients in the more rural parts of the country. Patients with cardio-vascular emergencies, trauma and neurological emergencies are among those patient groups most commonly seen. We conclude that the overall dispatch profile appears appropriate but emphasise that continuous development and refinement is essential.

The Danish helicopter emergency medical service database: high quality data with great potential.

BACKGROUND: The Danish Helicopter Emergency Medical Service (HEMS) is part of the Danish pre-hospital response offering advanced patient care on scene and during rapid transport to definitive care. Monitoring HEMS performance and the quality of critical care has high national as well as international priority underlining the need for research in this field. The data quality of the Danish HEMS database is unknown. Furthermore, a set of quality indicators (QI) developed by an international collaboration group (EQUIPE) potentially for use in physician-staffed EMS, has recently been presented. The aim of the current study was to present the design and data quality of the Danish helicopter database, and to evaluate the coverage of available variables in the database according to the QIs proposed. METHOD: The study included all helicopter dispatches between October 1st 2014 and April 30th 2018. The database layout and data entering procedure, as well as the key variables and data completeness were described. Furthermore, missing data and misclassifications were addressed. Lastly, the 26 QIs proposed by the EQUIPE-collaboration were evaluated for coverage in the HEMS database. RESULTS: A total of 13,392 missions were included in the study. The database includes a broad spectrum of mission- and patient-specific data related to the pre-hospital pathway of acutely ill or injured patients in a national coverage. Missing data for the majority of variables is less than 6.5%. The percentage of completed report forms has increased over time and reached 99.9% in 2018. Misclassification were observed for 294 patients in the study period corresponding to 3,7%. Less than half of the QIs proposed by the EQUIPE-collaboration group were directly available from the database. CONCLUSIONS: Helicopter Emergency Medical Services in Denmark are a new and sparsely investigated health care provider. The database contains nearly all missions dispatched by the five regional Emergency Medical Dispatch Centres. Generally, the data quality is considered high with great potential for future research. Potential quality indicators as proposed by the EQUIPE-collaboration group could inspire the configuration and design of the next version of Hemsfile creating an even more solid basis for research and quality improvement.

A nationwide investigation of CPR courses, books, and skill retention.

INTRODUCTION: Survival from Out-of-Hospital Cardiac Arrest is highly associated with bystander cardiopulmonary resuscitation. The quality of bystander CPR is influenced by citizens attending Basic Life Support (BLS) courses and the quality of these courses. The purpose of the study was to investigate content, quality and compliance with the European Resuscitation Council (ERC) guidelines in national Danish BLS courses and the skill retention. METHODS: Books from 16 different course providers were analyzed for compliance with guidelines using the principle of mutually exclusive and collectively exhaustive questioning. Observation of 56 BLS courses were conducted using an evaluation sheet, with a five-point Likert scale including theoretical, technical, and non-technical skills. BLS skills of participants were assessed with a follow-up test 4-6 months after a course using a modified Cardiff Test. RESULTS: Analysis of the books, showed compliance with ERC guidelines of 69% on the examined items. Courses using ERC educational structure and having maximum six participants per instructor were associated with high quality in the course observations and a better follow-up test. Especially, the use of automated external defibrillator showed significant odds ratio (OR) of 21.8 (95% CI 4.1-114.7) to 31.3 (95% CI 3.7-265.1) of achieving high quality on courses with similar results in the follow-up test. CONCLUSION: National BLS courses had significant variation in the content of books, and compliance to ERC guidelines during courses and in skills retention 4-6 months after the courses. This study can be used to further improve and standardize BLS courses.

Danish first aid books compliance with the new evidence-based non-resuscitative first aid guidelines.

BACKGROUND: The European Resuscitation Council (ERC) released new guidelines on resuscitation in 2015. For the first time, the guidelines included a separate chapter on first aid for laypersons. We analysed the current major Danish national first aid books to identify potential inconsistencies between the current books and the new evidence-based first aid guidelines. METHODS: We identified first aid books from all the first aid courses offered by major Danish suppliers. Based on the new ERC first aid guidelines, we developed a checklist of 26 items within 16 different categories to assess the content; this checklist was adapted following the principle of mutually exclusive and collectively exhaustive questioning. To assess the agreement between four raters, Fleiss' kappa test was used. Items that did not reach an acceptable kappa score were excluded. RESULTS: We evaluated 10 first aid books used for first aid courses and published between 2009 and 2015. The content of the books complied with the new in 38% of the answers. In 12 of the 26 items, there was less than 50% consistency. These items include proximal pressure points and elevation of extremities for the control of bleeding, use of cervical collars, treatment for an open chest wound, burn dressing, dental avulsion, passive leg raising, administration of bronchodilators, adrenaline, and aspirin. CONCLUSIONS: Danish course material showed significant inconsistencies with the new evidence-based first aid guidelines. The new knowledge from the evidence-based guidelines should be incorporated into revised and updated first aid course material.

The Effects of Public Access Defibrillation on Survival After Out-of-Hospital Cardiac Arrest: A Systematic Review of Observational Studies.

BACKGROUND: Despite recent advances, the average survival after out-of-hospital cardiac arrest (OHCA) remains <10%. Early defibrillation by an automated external defibrillator is the most important intervention for patients with OHCA, showing survival proportions >50%. Accordingly, placement of automated external defibrillators in the community as part of a public access defibrillation program (PAD) is recommended by international guidelines. However, different strategies have been proposed on how exactly to increase and make use of publicly available automated external defibrillators. This systematic review aimed to evaluate the effect of PAD and the different PAD strategies on survival after OHCA. METHODS: PubMed, Embase, and the Cochrane Library were systematically searched on August 31, 2015 for observational studies reporting survival to hospital discharge in OHCA patients where an automated external defibrillator had been used by nonemergency medical services. PAD was divided into 3 groups according to who applied the defibrillator: nondispatched lay first responders, professional first responders (firefighters/police) dispatched by the Emergency Medical Dispatch Center (EMDC), or lay first responders dispatched by the EMDC. RESULTS: A total of 41 studies were included; 18 reported PAD by nondispatched lay first responders, 20 reported PAD by EMDC-dispatched professional first responders (firefighters/police), and 3 reported both. We identified no qualified studies reporting survival after PAD by EMDC-dispatched lay first responders. The overall survival to hospital discharge after OHCA treated with PAD showed a median survival of 40.0% (range, 9.1-83.3). Defibrillation by nondispatched lay first responders was associated with the highest survival with a median survival of 53.0% (range, 26.0-72.0), whereas defibrillation by EMDC-dispatched professional first responders (firefighters/police) was associated with a median survival of 28.6% (range, 9.0-76.0). A meta-analysis of the different survival outcomes could not be performed because of the large heterogeneity of the included studies. CONCLUSIONS: This systematic review showed a median overall survival of 40% for patients with OHCA treated by PAD. Defibrillation by nondispatched lay first responders was found to correlate with the highest impact on survival in comparison with EMDC-dispatched professional first responders. PAD by EMDC-dispatched lay first responders could be a promising strategy, but evidence is lacking.

Recognising out-of-hospital cardiac arrest during emergency calls increases bystander cardiopulmonary resuscitation and survival.

BACKGROUND: Initiation of early bystander cardiopulmonary resuscitation (CPR) depends on bystanders' or medical dispatchers' recognition of out-of-hospital cardiac arrest (OHCA). The primary aim of our study was to investigate if OHCA recognition during the emergency call was associated with bystander CPR, return of spontaneous circulation (ROSC), and 30-day survival. Our secondary aim was to identify patient-, setting-, and dispatcher-related predictors of OHCA recognition. METHODS: We performed an observational study of all OHCA patients' emergency calls in the Capital Region of Denmark from 01/01/2013-31/12/2013. OHCAs were collected from the Danish Cardiac Arrest Registry and the Mobile Critical Care Unit database. Emergency call recordings were identified and evaluated. Multivariable logistic regression analyses were applied to all OHCAs and witnessed OHCAs only to analyse the association between OHCA recognition and bystander CPR, ROSC, and 30-day survival. Univariable logistic regression analyses were applied to identify predictors of OHCA recognition. RESULTS: We included 779 emergency calls in the analyses. During the emergency calls, 70.1% (n=534) of OHCAs were recognised; OHCA recognition was positively associated with bystander CPR (odds ratio [OR]=7.84, 95% confidence interval [CI]: 5.10-12.05) in all OHCAs; and ROSC (OR=1.86, 95% CI: 1.13-3.06) and 30-day survival (OR=2.80, 95% CI: 1.58-4.96) in witnessed OHCA. Predictors of OHCA recognition were addressing breathing (OR=1.76, 95% CI: 1.17-2.66) and callers located by the patient's side (OR=2.16, 95% CI: 1.46-3.19). CONCLUSIONS: Recognition of OHCA during emergency calls was positively associated with the provision of bystander CPR, ROSC, and 30-day survival in witnessed OHCA.

The difficult medical emergency call: A register-based study of predictors and outcomes.

BACKGROUND: Pre-hospital emergency care requires proper categorization of emergency calls and assessment of emergency priority levels by the medical dispatchers. We investigated predictors for emergency call categorization as "unclear problem" in contrast to "symptom-specific" categories and the effect of categorization on mortality. METHODS: Register-based study in a 2-year period based on emergency call data from the emergency medical dispatch center in Copenhagen combined with nationwide register data. Logistic regression analysis (N = 78,040 individuals) was used for identification of predictors of emergency call categorization as "unclear problem". Poisson regression analysis (N = 97,293 calls) was used for examining the effect of categorization as "unclear problem" on mortality. RESULTS: "Unclear problem" was the registered category in 18% of calls. Significant predictors for "unclear problem" categorization were: age (odds ratio (OR) 1.34 for age group 76+ versus 18-30 years), ethnicity (OR 1.27 for non-Danish vs. Danish), day of week (OR 0.92 for weekend vs. weekday), and time of day (OR 0.79 for night vs. day). Emergency call categorization had no effect on mortality for emergency priority level A calls, incidence rate ratio (IRR) 0.99 (95% confidence interval (CI) 0.90-1.09). For emergency priority level B calls, an association was observed, IRR 1.26 (95% CI 1.18-1.36). DISCUSSIONS: The results shed light on the complexity of emergency call handling, but also implicate a need for further improvement. Educational interventions at the dispatch centers may improve the call handling, but also the underlying supportive tools are modifiable. The higher mortality rate for patients with emergency priority level B calls with "unclear problem categorization" could imply lowering the threshold for dispatching a high level ambulance response when the call is considered unclear. On the other hand a "benefit of the doubt" approach could hinder the adequate response to other patients in need for an ambulance as there is an increasing demand and limited resources for ambulance services. CONCLUSIONS: Age, ethnicity, day of week and time of day were significant predictors of emergency call categorization as "unclear problem". "Unclear problem" categorization was not associated with mortality for emergency priority level A calls, but a higher mortality was observed for emergency priority level B calls.

Recognition of out-of-hospital cardiac arrest during emergency calls - a systematic review of observational studies.

BACKGROUND: The medical dispatcher plays an essential role as part of the first link in the Chain of Survival, by recognising the out-of-hospital cardiac arrest (OHCA) during the emergency call, dispatching the appropriate first responder or emergency medical services response, performing dispatcher assisted cardiopulmonary resuscitation, and referring to the nearest automated external defibrillator. The objective of this systematic review was to evaluate and compare studies reporting recognition of OHCA patients during emergency calls. METHODS: This systematic review was reported in compliance with the PRISMA guidelines. We systematically searched MEDLINE, Embase and the Cochrane Library on 4 November 2015. Observational studies, reporting the proportion of clinically confirmed OHCAs that was recognised during the emergency call, were included. Two authors independently screened abstracts and full-text articles for inclusion. Data were extracted and the risk of bias within studies was assessed using the QUADAS-2 tool for quality assessment of diagnostic accuracy studies. RESULTS: A total of 3,180 abstracts were screened for eligibility and 53 publications were assessed in full-text. We identified 16 studies including 6,955 patients that fulfilled the criteria for inclusion in the systematic review. The studies reported recognition of OHCA with a median sensitivity of 73.9% (range: 14.1-96.9%). The selection of study population and the definition of "recognised OHCA" (threshold for positive test) varied greatly between the studies, resulting in high risk of bias. Heterogeneity in the studies precluded meta-analysis. CONCLUSION: Among the 16 included studies, we found a median sensitivity for OHCA recognition of 73.9% (range: 14.1-96.9%). However, great heterogeneity between study populations and in the definition of "recognised OHCA", lead to insufficient comparability of results. Uniform and transparent reporting is required to ensure comparability and development towards best practice.

Recognition of out-of-hospital cardiac arrest by medical dispatchers in emergency medical dispatch centres in two countries.

INTRODUCTION: Survival after out-of-hospital cardiac arrest (OHCA) remains low. Early recognition by emergency medical dispatchers is essential for an effective chain of actions, leading to early cardiopulmonary resuscitation, use of an automated external defibrillator and rapid dispatching of the emergency medical services. AIM: To analyse and compare the accuracy of OHCA recognition by medical dispatchers in two countries. METHOD: An observational register-based study collecting data from national cardiac arrest registers in Denmark and Sweden during a six-month period in 2013. Data were analysed in two steps; registry data were merged with electronically registered emergency call data from the emergency medical dispatch centres in the two regions. Cases with missing or non-OHCA dispatch codes were analysed further by auditing emergency call recordings using a uniform data collection template. RESULTS: The sensitivity for recognition of OHCA was 40.9% (95% CI: 37.1-44.7%) in the Capital Region of Denmark and 78.4% (95% CI: 73.2-83.0%) in the Skåne Region in Sweden (p<0.001). With additional data from the emergency call recordings, the sensitivity was 80.7% (95% CI: 77.7-84.3%) and 86.0% (95% CI: 81.3-89.8%) for the two regions (p=0.06). The majority of the non-recognised OHCA were dispatched with the highest priority. CONCLUSION: The accuracy of OHCA recognition was high and comparable. We identified large differences in data registration practices despite the use of similar dispatch tools. This raises a discussion of definitions and transparency in general in scientific reporting of OHCA recognition, which is essential if used as quality indicator in emergency medical services.

Medical dispatchers recognise substantial amount of acute stroke during emergency calls.

BACKGROUND: Immediate recognition of stroke symptoms is crucial to ensure timely access to revascularisation therapy. Medical dispatchers ensure fast admission to stroke facilities by prioritising the appropriate medical response. Data on medical dispatchers' ability to recognise symptoms of acute stroke are therefore critical in organising emergency stroke care. We aimed to describe the sensitivity and positive predictive value of medical dispatchers' ability to recognise acute stroke during emergency calls, and to identify factors associated with recognition. METHODS: This was an observational study of 2653 consecutive unselected patients with a final diagnosis of stroke or transient ischemic attack (TIA). All admitted through the Emergency Medical Services Copenhagen, during a 2-year study period (2012-2014). Final diagnoses were matched with dispatch codes from the Emergency Medical Dispatch Centre. Sensitivity and positive predictive value were calculated. The effect of age, gender, and time-of-day was analysed using multivariable logistic regression. RESULTS: The sensitivity was 66.2 % (95 % CI: 64.4 %-68.0 %), and the positive predictive value was 30.2 % (95 % CI: 29.1 %-31.4 %). The multivariable logistic regression analyses showed that emergency calls during daytime and a final diagnosis of TIA vs. intracerebral haemorrhage (ICH), was positively associated with recognition of stroke (OR 2.70, 95 % CI: 2.04-3.57). DISCUSSION: This study reports a high rate of stroke recognition compared to other studies ranging from 31% to 74%. The high sensitivity is likely the result of a profound reorganisation of the Emergency Medical ServicesCopenhagen, including the introduction of EMDs with a medical profession, and a criteria-based dispatch tool. A recognition rate of 100 % is not obtainable without an inappropriate amount of false positive cases. CONCLUSIONS: We report an overall high recognition of stroke by medical dispatchers. A final diagnosis of TIA, compared to ICH, was positively associated with recognition of acute stroke. Emergency medical dispatchers serve as the essential first step in ensuring fast-track stroke treatment, which would promote timely acute therapy. TRIAL REGISTRATION: Unique identifier: NCT02191514.

Why and when citizens call for emergency help: an observational study of 211,193 medical emergency calls.

BACKGROUND: A medical emergency call is citizens' access to pre-hospital emergency care and ambulance services. Emergency medical dispatchers are gatekeepers to provision of pre-hospital resources and possibly hospital admissions. We explored causes for access, emergency priority levels, and temporal variation within seasons, weekdays, and time of day for emergency calls to the emergency medical dispatch center in Copenhagen in a two-year study period (December 1(st), 2011 to November 30(th), 2013). METHODS: Descriptive analysis was performed for causes for access and emergency priority levels. A Poisson regression model was used to calculate adjusted ratio estimates for the association between seasons, weekdays, and time of day overall and stratified by emergency priority levels. RESULTS: We analyzed 211,193 emergency calls for temporal variation. Of those, 167,635 calls were eligible for analysis of causes and emergency priority level. "Unclear problem" was the most frequent category (19%). The five most common causes with known origin were categorized as "Wounds, fractures, minor injuries" (13%), "Chest pain/heart disease" (11%), "Accidents" (9%), "Intoxication, poisoning, drug overdose" (8%), and "Breathing difficulties" (7%). The highest emergency priority levels (Emergency priority level A and B) were assigned in 81% of calls. In the analysis of temporal variation, the total number of calls peaked at wintertime (26%), Saturdays (16%), and during daytime (39%). CONCLUSION: The pattern of citizens' contact causes fell into four overall categories: unclear problems, medical problems, intoxication and accidents. The majority of calls were urgent. The magnitude of unclear problems represents a modifiable factor and highlights the potential for further improvement of supportive dispatch priority tools or educational interventions at dispatch centers. Temporal variation was identified within seasons, weekdays and time of day and reflects both system load and disease occurrence. Data on contact patterns could be utilized in a public health perspective, benchmarking of EMS systems, and ultimately development of best practice in the area of emergency medicine.