Comparison of Medical Priority Dispatch (MPD) and Criteria Based Dispatch (CBD) relating to cardiac arrest calls

2024 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations: Summary From the Basic Life Support; Advanced Life Support; Pediatric Life Support; Neonatal Life Support; Education, Implementation, and Teams; and First Aid Task Forces

This is the eighth annual summary of the International Liaison Committee on Resuscitation International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations; a more comprehensive review was done in 2020. This latest summary addresses the most recent published resuscitation evidence reviewed by the International Liaison Committee on Resuscitation task force science experts. Members from 6 International Liaison Committee on Resuscitation task forces have assessed, discussed, and debated the quality of the evidence, using Grading of Recommendations Assessment, Development, and Evaluation criteria, and their statements include consensus treatment recommendations. Insights into the deliberations of the task forces are provided in the Justification and Evidence-to-Decision Framework Highlights sections. In addition, the task forces list priority knowledge gaps for further research.

Optimising telecommunicator recognition of out-of-hospital cardiac arrest: A scoping review

Aim

To summarize existing literature and identify knowledge gaps regarding barriers and enablers of telecommunicators' recognition of out-of-hospital cardiac arrest (OHCA).

Methods

This scoping review was undertaken by an International Liaison Committee on Resuscitation (ILCOR) Basic Life Support scoping review team and guided by the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for scoping reviews (PRISMA-ScR). Studies were eligible for inclusion if they were peer-reviewed and explored barriers and enablers of telecommunicator recognition of OHCA. We searched Ovid MEDLINE® and Embase and included articles from database inception till June 18th, 2024.

Results

We screened 9,244 studies and included 62 eligible studies on telecommunicator recognition of OHCA. The studies ranged in methodology. The majority were observational studies of emergency calls. The barriers most frequently described to OHCA recognition were breathing status and agonal breathing. The most frequently tested enabler for recognition was a variety of dispatch protocols focusing on breathing assessment. Only one randomized controlled trial (RCT) was identified, which found no difference in OHCA recognition with the addition of machine learning alerting telecommunicators in suspected OHCA cases.

Conclusion

Most studies were observational, assessed barriers to recognition of OHCA and compared different dispatch protocols. Only one RCT was identified. Randomized trials should be conducted to inform how to improve telecommunicator recognition of OHCA, including recognition of pediatric OHCAs and assessment of dispatch protocols.

2024 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations: Summary From the Basic Life Support; Advanced Life Support; Pediatric Life Support; Neonatal Life Support; Education, Implementation, and Teams; and First Aid Task Forces

This is the eighth annual summary of the International Liaison Committee on Resuscitation International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations; a more comprehensive review was done in 2020. This latest summary addresses the most recent published resuscitation evidence reviewed by the International Liaison Committee on Resuscitation task force science experts. Members from 6 International Liaison Committee on Resuscitation task forces have assessed, discussed, and debated the quality of the evidence, using Grading of Recommendations Assessment, Development, and Evaluation criteria, and their statements include consensus treatment recommendations. Insights into the deliberations of the task forces are provided in the Justification and Evidence-to-Decision Framework Highlights sections. In addition, the task forces list priority knowledge gaps for further research.

Barriers to successful dispatcher-assisted cardiopulmonary resuscitation in out-of-hospital cardiac arrest in Korea

Introduction

Dispatcher-assisted cardiopulmonary resuscitation (DA-CPR) improves bystander CPR rates and survival outcomes. This study aimed to identify barriers to successful DA-CPR in patients with out-of-hospital cardiac arrest (OHCA).

Methods

This retrospective observational study used data from a nationwide OHCA database from 2017 to 2021. Adult emergency medical services (EMS)-treated patients with OHCA with a presumed cardiac etiology were enrolled. The main exposure variable was compliance with DA-CPR. The primary outcome was good neurological recovery at hospital discharge. Multivariable logistic regression analysis was conducted to identify the major factors associated with unsuccessful DA-CPR with and without multiple imputations. Causal mediation analysis was conducted using witnessed status as a mediator.

Results

In the final analysis, 49,165 patients with OHCA were included. A total of 36,865 (75.0%) patients successfully underwent DA-CPR. A higher proportion of good neurological recovery was observed in the successful DA-CPR group than in the non-successful DA-CPR group (P < 0.001). The following factors were identified as risk factors for unsuccessful DA-CPR: age > 65 years, male sex, OHCA occurring in a non-metropolitan area or private place, unwitnessed status, whether the bystander was a non-family member or non-cohabitant, female sex or had not received CPR training, and primary call dispatchers not receiving any first-aid training. Additional analyses after multiple imputations showed similar results. Mediation effect was significant for most risk factors for unsuccessful DA-CPR.

Conclusions

Bystander characteristics (non-family member or non-cohabitant, female, and uneducated status for CPR) and primary call dispatchers not receiving first-aid training were identified as risk factors for unsuccessful DA-CPR.

Compression-Only or Standard Cardiopulmonary Resuscitation for Trained Laypersons in Out-of-Hospital Cardiac Arrest: A Nationwide Randomized Trial in Sweden

BACKGROUND

The ongoing TANGO2 (Telephone Assisted CPR. AN evaluation of efficacy amonGst cOmpression only and standard CPR) trial is designed to evaluate whether compression-only cardiopulmonary resuscitation (CPR) by trained laypersons is noninferior to standard CPR in adult out-of-hospital cardiac arrest. This pilot study assesses feasibility, safety, and intermediate clinical outcomes as part of the larger TANGO2 survival trial.

METHODS

Emergency medical dispatch calls of suspected out-of-hospital cardiac arrest were screened for inclusion at 18 dispatch centers in Sweden between January 1, 2017, and March 12, 2020. Inclusion criteria were witnessed event, bystander on the scene with previous CPR training, age above 18 years of age, and no signs of trauma, pregnancy, or intoxication. Cases were randomized 1:1 at the dispatch center to either instructions to perform compression-only CPR (intervention) or instructions to perform standard CPR (control). Feasibility included evaluation of inclusion, randomization, and adherence to protocol. Safety measures were time to emergency medical service dispatch CPR instructions, and to start of CPR, intermediate clinical outcome was defined as 1-day survival.

RESULTS

Of 11 838 calls of suspected out-of-hospital cardiac arrest screened for inclusion, 2168 were randomized and 1250 (57.7%) were out-of-hospital cardiac arrests treated by the emergency medical service. Of these, 640 were assigned to intervention and 610 to control. Crossover from intervention to control occurred in 16.3% and from control to intervention in 18.5%. The median time from emergency call to ambulance dispatch was 1 minute and 36 s (interquartile range, 1.1-2.2) in the intervention group and 1 minute and 30 s (interquartile range, 1.1-2.2) in the control group. Survival to 1 day was 28.6% versus 28.4% (P=0.984) for intervention and control, respectively.

CONCLUSIONS

In this national randomized pilot trial, compression-only CPR versus standard CPR by trained laypersons was feasible. No differences in safety measures or short-term survival were found between the 2 strategies. Efforts to reduce crossover are important and may strengthen the ongoing main trial that will assess differences in long-term survival.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT02401633.

Swedish emergency medical dispatch centres' ability to answer emergency medical calls and dispatch an ambulance in response to out-of-hospital cardiac arrest calls in accordance with the American Heart Association performance goals: An observational study

AIM

To investigate the ability of Swedish Emergency Medical Dispatch Centres (EMDCs) to answer medical emergency calls and dispatch an ambulance for out-of-hospital cardiac arrest (OHCA) in accordance with the American Heart Association (AHA) performance goals in a 1-step (call connected directly to the EMDC) and a 2-step (call transferred to regional EMDC) procedure over 10 years, and to assess whether delays may be associated with 30-day survival.

METHOD

Observational data from the Swedish Registry for Cardiopulmonary Resuscitation and EMDC.

RESULTS

A total of 9,174,940 medical calls were answered (1-step). The median answer delay was 7.3 s (interquartile range [IQR], 3.6-14.5 s). Furthermore, 594,008 calls (6.1%) were transferred in a 2-step procedure, with a median answer delay of 39 s (IQR, 30-53 s). A total of 45,367 cases (0.5%, 1-step) were registered as OHCA, with a median answer delay of 7.2 s (IQR, 3.6-14.1 s) (AHA high-performance goal, 10 s). For 1-step procedure, no difference in 30-day survival was found regarding answer delay. For OHCA (1-step), an ambulance was dispatched after a median of 111.9 s (IQR, 81.7-159.9 s). Thirty-day survival was 10.8% (n = 664) when an ambulance was dispatched within 70 s (AHA high-performance) versus 9.3% (n = 2174) > 100 s (AHA acceptable) (p = 0.0013). Outcome data in the 2-step procedure was unobtainable.

CONCLUSION

The majority of calls were answered within the AHA performance goals. When an ambulance was dispatched within the AHA high-performance standard in response to OHCA calls, survival was higher compared with calls when dispatch was delayed.

Optimizing an Emergency Medical Dispatch System to Improve Prehospital Diagnosis and Treatment of Acute Coronary Syndrome: Nationwide Retrospective Study in China

Background

Acute coronary syndrome (ACS) is the most time-sensitive acute cardiac event that requires rapid dispatching and response. The medical priority dispatch system (MPDS), one of the most extensively used types of emergency dispatch systems, is hypothesized to provide better-quality prehospital emergency treatment. However, few studies have revealed the impact of MPDS use on the process of ACS care.

Objective

This study aimed to investigate whether the use of MPDS was associated with higher prehospital diagnosis accuracy and shorter prehospital delay for patients with ACS transferred by an emergency medical service (EMS), using a national database in China.

Methods

This retrospective analysis was based on an integrated database of China’s MPDS and hospital registry. From January 1, 2016, to December 31, 2020, EMS-treated ACS cases were divided into before MPDS and after MPDS groups in accordance with the MPDS launch time at each EMS center. The primary outcomes included diagnosis consistency between hospital admission and discharge, and prehospital delay. Multivariable logistic regression and propensity score–matching analysis were performed to compare outcomes between the 2 groups for total ACS and subtypes.

Results

A total of 9806 ACS cases (3561 before MPDS and 6245 after MPDS) treated by 43 EMS centers were included. The overall diagnosis consistency of the after MPDS group (Cohen κ=0.918, P<.001) was higher than that of the before MPDS group (Cohen κ=0.889, P<.001). After the use of the MPDS, the call-to-EMS arrival time was shortened in the matched ACS cases (20.0 vs 16.0 min, P<.001; adjusted difference: –1.67, 95% CI –2.33 to –1.02; P<.001) and in the subtype of ST-elevation myocardial infarction (adjusted difference: –3.81, 95% CI –4.63 to –2.98, P<.001), while the EMS arrival-to-door time (20.0 vs 20.0 min, P=.31) was not significantly different in all ACS cases and subtypes.

Conclusions

The optimized use of MPDS in China was associated with increased diagnosis consistency and a reduced call-to-EMS arrival time among EMS-treated patients with ACS. An emergency medical dispatch system should be designed specifically to fit into different prehospital modes in the EMS system on a regional basis.

Improving ambulance dispatch triage to trauma: A scoping review using the framework of development and evaluation of clinical prediction rules

OBJECTIVE

Ambulance dispatch algorithms should function as clinical prediction rules, identifying high acuity patients for advanced life support, and low acuity patients for non-urgent transport. Systematic reviews of dispatch algorithms are rare and focus on study types specific to the final phases of rule development, such as impact studies, and may miss the complete value-added evidence chain. We sought to summarise the literature for studies seeking to improve dispatch in trauma by performing a scoping review according to standard frameworks for developing and evaluating clinical prediction rules.

METHODS

We performed a scoping review searching MEDLINE, EMBASE, CINAHL, the CENTRAL trials registry, and grey literature from January 2005 to October 2021. We included all study types investigating dispatch triage to injured patients in the English language. We reported the clinical prediction rule phase (derivation, validation, impact analysis, or user acceptance) and the performance and outcomes measured for high and low acuity trauma patients.

RESULTS

Of 2067 papers screened, we identified 12 low and 30 high acuity studies. Derivation studies were most common (52%) and rule-based computer-aided dispatch was the most frequently investigated (23 studies). Impact studies rarely reported a prior validation phase, and few validation studies had their impact investigated. Common outcome measures in each phase were infrequent (0 to 27%), making a comparison between protocols difficult. A series of papers for low acuity patients and another for pediatric trauma followed clinical prediction rule development. Some low acuity Medical Priority Dispatch System codes are associated with the infrequent requirement for advanced life support and clinician review of computer-aided dispatch may enhance dispatch triage accuracy in studies of helicopter emergency medical services.

CONCLUSIONS

Few derivation and validation studies were followed by an impact study, indicating important gaps in the value-added evidence chain. While impact studies suggest clinician oversight may enhance dispatch, the opportunity exists to standardize outcomes, identify trauma-specific low acuity codes, and develop intelligent dispatch systems.

Swedish dispatchers’ compliance with the American Heart Association performance goals for dispatch-assisted cardiopulmonary resuscitation and its association with survival in out-of-hospital cardiac arrest: A retrospective study

Aim

We aimed 1) to investigate how Swedish dispatchers perform during emergency calls in accordance with the American Heart Association (AHA) goals for dispatcher-assisted cardiopulmonary resuscitation (DA-CPR), 2) calculate the potential impact on 30-day survival.

Methods

This observational study includes a random sample of 1000 out-of-hospital cardiac arrest (OHCA) emergency ambulance calls during 2018 in Sweden. Voice logs were audited to evaluate dispatchers’ handling of emergency calls according to the AHA performance goals. Number of possible additional survivors was estimated assuming the timeframes of the AHA performance goals was achieved.

Results

A total of 936 cases were included. An OHCA was recognized by a dispatcher in 79% (AHA goal 75%). In recognizable OHCA, dispatchers recognized 85% (AHA goal 95%). Dispatch-directed compressions were given in 61% (AHA goal 75%). Median time to OHCA recognition was 113 s [interquartile range (IQR), 62, 204 s] (AHA goal < 60 s). The first dispatch-directed compression was performed at a median time of 240 s [IQR, 176, 332 s] (AHA goal < 90 s). If eligible patients receive dispatch-directed compressions within the AHA 90 s goal, 73 additional lives may be saved; if all cases are recognized within the AHA 60 s goal, 25 additional lives may be saved.

Conclusions

The AHA policy statement serves as a benchmark for all emergency medical dispatch centres (EMDC). Additional effort is needed at Swedish EMDC to achieve AHA goals for DA-CPR. Our study suggests that if EMDC further optimize handling of OHCA calls in accordance with AHA goals, many more lives may be saved.

Features of Emergency Medical System calls that facilitate or inhibit Emergency Medical Dispatcher recognition that a patient is in, or at imminent risk of, cardiac arrest: A systematic mixed studies review

Aim

To identify and appraise evidence relating to the features of an Emergency Medicine System call interaction that enable, or inhibit, an Emergency Medical Dispatcher’s recognition that a patient is in out-of-hospital cardiac arrest, or at imminent risk of out-of-hospital cardiac arrest.

Methods

All study designs were eligible for inclusion. Data sources included Medline, BNI, CINAHL, EMBASE, PubMed, Cochrane Database of Systematic Reviews, AMED and OpenGrey. Stakeholder resources were screened and experts in resuscitation were asked to review the studies identified. Studies were appraised using the Mixed Methods Appraisal Tool. Synthesis was completed using a segregated mixed research synthesis approach.

Results

Thirty-two studies were included in the review. Three main themes were identified: Key features of the Emergency Medical Service call interaction; Managing the Emergency Medical Service call; Emotional distress.

Conclusion

A dominant finding is the difficulty in recognising abnormal/agonal breathing during the Emergency Medical Service call. The interaction between the caller and the Emergency Medical Dispatcher is critical in the recognition of patients who suffer an out-of-hospital cardiac arrest. Emergency Medical Dispatchers adapt their approach to the Emergency Medical Service call, and regular training for Emergency Medical Dispatchers is recommended to optimise out-of-hospital cardiac arrest recognition. Further research is required with a focus on the Emergency Medical Service call interaction of patients who are alive at the time of the Emergency Medical Service call and who later deteriorate into OHCA.

PROSPERO registration: CRD42019155458.

Different forms of bystander cardiopulmonary resuscitation in out-of-hospital cardiac arrest

Out-of-hospital cardiac arrest (OHCA) is a major cause of death in the Western world with an estimated number of 275 000 treated with resuscitation attempts by the Emergency Medical Services (EMS) in Europe each year. Overall survival rates remain low, and most studies indicate that around 1 out 10 will survive to 30 days. Amongst the strongest factors associated with survival in OHCA is first recorded rhythm amendable to defibrillation, early defibrillation and prompt initiation of cardiopulmonary resuscitation (CPR). Overall, CPR started prior to EMS arrival has repeatedly been shown to be associated with survival rates 2-3 times higher compared with no such initiation. The primary goal of CPR is to generate sufficient blood flow to vital organs, mainly the brain and heart, until restoration of spontaneous circulation can be achieved. Barriers to the initiation of CPR by bystanders in OHCA include fear of being incapable, causing harm, and transmission of infectious diseases. Partly due to these barriers, and low rates of CPR, the concept of CPR with compression only was proposed as a simpler form of resuscitation with the aim to be more widely accepted by the public in the 1990s. But how reliable is the evidence supporting this simpler form of CPR, and are the outcomes after CO-CPR comparable to standard CPR?

Income-related differences in out-of-hours primary care telephone triage using national registration data

BACKGROUND

Telephone triage is used to facilitate efficient and adequate acute care allocation, for instance in out-of-hours primary care services (OPCSs). Remote assessment of health problems is challenging and could be impeded by a patient's ambiguous formulation of his or her healthcare need. Socioeconomically vulnerable patients may experience more difficulty in expressing their healthcare need. We aimed to assess whether income differences exist in the patient's presented symptoms, assessed urgency and allocation of follow-up care in OPCS.

METHOD

Data were derived from Nivel Primary Care Database encompassing electronic health record data of 1.3 million patients from 28 OPCSs in 2017 in the Netherlands. These were linked to sociodemographic population registry data. Multilevel logistic regression analyses (contacts clustered in patients), adjusted for patient characteristics (eg, age, sex), were conducted to study associations of symptoms, urgency assessment and follow-up care with patients' income (standardised for household size as socioeconomic status (SES) indicator).

RESULTS

The most frequently presented symptoms deduced during triage slightly differed across SES groups, with a larger relative share of trauma in the high-income groups. No SES differences were observed in urgency assessment. After triage, low income was associated with a higher probability of receiving telephone advice and home visits, and fewer consultations at the OPCS.

CONCLUSIONS

SES differences in the patient's presented symptom and in follow-up in OPCS suggest that the underlying health status and the ability to express care needs affect the telephone triage process . Further research should focus on opportunities to better tailor the telephone triage process to socioeconomically vulnerable patients.

European Resuscitation Council Guidelines 2021: Systems saving lives

The European Resuscitation Council (ERC) has produced these Systems Saving Lives guidelines, which are based on the 2020 International Consensus on Cardiopulmonary Resuscitation Science with Treatment Recommendations. The topics covered include chain of survival, measuring performance of resuscitation, social media and smartphones apps for engaging community, European Restart a Heart Day, World Restart a Heart, KIDS SAVE LIVES campaign, lower-resource setting, European Resuscitation Academy and Global Resuscitation Alliance, early warning scores, rapid response systems, and medical emergency team, cardiac arrest centres and role of dispatcher.

Machine learning can support dispatchers to better and faster recognize out-of-hospital cardiac arrest during emergency calls: A retrospective study

AIM

Fast recognition of out-of-hospital cardiac arrest (OHCA) by dispatchers might increase survival. The aim of this observational study of emergency calls was to (1) examine whether a machine learning framework (ML) can increase the proportion of calls recognizing OHCA within the first minute compared with dispatchers, (2) present the performance of ML with different false positive rate (FPR) settings, (3) examine call characteristics influencing OHCA recognition.

METHODS

ML can be configured with different FPR settings, i.e., more or less inclined to suspect an OHCA depending on the predefined setting. ML OHCA recognition within the first minute is evaluated with a 1.5 FPR as the primary endpoint, and other FPR settings as secondary endpoints. ML was exposed to a random sample of emergency calls from 2018. Voice logs were manually audited to evaluate dispatchers time to recognition.

RESULTS

Of 851 OHCA calls, the ML recognized 36% (n = 305) within 1 min compared with 25% (n = 213) by dispatchers. The recognition rate at any time during the call was 86% for ML and 84% for dispatchers, with a median time to recognition of 72 versus 94 s. OHCA recognized by both ML and dispatcher showed a 28 s mean difference in favour of ML (P < 0.001). ML with higher FPR settings reduced recognition times.

CONCLUSION

ML recognized a higher proportion of OHCA within the first minute compared with dispatchers and has the potential to be a supportive tool during emergency calls. The optimal FPR settings need to be evaluated in a prospective study.

Diagnosis of out-of-hospital cardiac arrest by emergency medical dispatch: A diagnostic systematic review

INTRODUCTION

Cardiac arrest is a time-sensitive condition requiring urgent intervention. Prompt and accurate recognition of cardiac arrest by emergency medical dispatchers at the time of the emergency call is a critical early step in cardiac arrest management allowing for initiation of dispatcher-assisted bystander CPR and appropriate and timely emergency response. The overall accuracy of dispatchers in recognizing cardiac arrest is not known. It is also not known if there are specific call characteristics that impact the ability to recognize cardiac arrest.

METHODS

We performed a systematic review to examine dispatcher recognition of cardiac arrest as well as to identify call characteristics that may affect their ability to recognize cardiac arrest at the time of emergency call. We searched electronic databases for terms related to "emergency medical dispatcher", "cardiac arrest", and "diagnosis", among others, with a focus on studies that allowed for calculating diagnostic test characteristics (e.g. sensitivity and specificity). The review was consistent with Grading of Recommendations, Assessment, Development and Evaluation (GRADE) method for evidence evaluation.

RESULTS

We screened 2520 article titles, resulting in 47 studies included in this review. There was significant heterogeneity between studies with a high risk of bias in 18 of the 47 which precluded performing meta-analyses. The reported sensitivities for cardiac arrest recognition ranged from 0.46 to 0.98 whereas specificities ranged from 0.32 to 1.00. There were no obvious differences in diagnostic accuracy between different dispatching criteria/algorithms or with the level of education of dispatchers.

CONCLUSION

The sensitivity and specificity of cardiac arrest recognition at the time of emergency call varied across dispatch centres and did not appear to differ by dispatch algorithm/criteria used or education of the dispatcher, although comparisons were hampered by heterogeneity across studies. Future efforts should focus on ways to improve sensitivity of cardiac arrest recognition to optimize patient care and ensure appropriate and timely resource utilization.

Adult Basic Life Support: International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations

This 2020 International Consensus on Cardiopulmonary Resuscitation (CPR) and Emergency Cardiovascular Care Science With Treatment Recommendations on basic life support summarizes evidence evaluations performed for 20 topics that were prioritized by the Basic Life Support Task Force of the International Liaison Committee on Resuscitation. The evidence reviews include 16 systematic reviews, 3 scoping reviews, and 1 evidence update. Per agreement within the International Liaison Committee on Resuscitation, new or revised treatment recommendations were only made after a systematic review.

Systematic reviews were performed for the following topics: dispatch diagnosis of cardiac arrest, use of a firm surface for CPR, sequence for starting CPR (compressions-airway-breaths versus airway-breaths-compressions), CPR before calling for help, duration of CPR cycles, hand position during compressions, rhythm check timing, feedback for CPR quality, alternative techniques, public access automated external defibrillator programs, analysis of rhythm during chest compressions, CPR before defibrillation, removal of foreign-body airway obstruction, resuscitation care for suspected opioid-associated emergencies, drowning, and harm from CPR to victims not in cardiac arrest.

The topics that resulted in the most extensive task force discussions included CPR during transport, CPR before calling for help, resuscitation care for suspected opioid-associated emergencies, feedback for CPR quality, and analysis of rhythm during chest compressions. After discussion of the scoping reviews and the evidence update, the task force prioritized several topics for new systematic reviews.

Adult Basic Life Support: 2020 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations

This2020 International Consensus on Cardiopulmonary Resuscitation(CPR)and Emergency Cardiovascular Care Science With Treatment Recommendationson basic life support summarizes evidence evaluations performed for 22 topics that were prioritized by the Basic Life Support Task Force of the International Liaison Committee on Resuscitation. The evidence reviews include 16 systematic reviews, 5 scoping reviews, and 1 evidence update. Per agreement within the International Liaison Committee on Resuscitation, new or revised treatment recommendations were only made after a systematic review.

Systematic reviews were performed for the following topics: dispatch diagnosis of cardiac arrest, use of a firm surface for CPR, sequence for starting CPR (compressions-airway-breaths versus airway-breaths-compressions), CPR before calling for help, duration of CPR cycles, hand position during compressions, rhythm check timing, feedback for CPR quality, alternative techniques, public access automated external defibrillator programs, analysis of rhythm during chest compressions, CPR before defibrillation, removal of foreign-body airway obstruction, resuscitation care for suspected opioid-associated emergencies, drowning, and harm from CPR to victims not in cardiac arrest.

The topics that resulted in the most extensive task force discussions included CPR during transport, CPR before calling for help, resuscitation care for suspected opioid-associated emergencies, feedback for CPR quality, and analysis of rhythm during chest compressions. After discussion of the scoping reviews and the evidence update, the task force prioritized several topics for new systematic reviews.

Identifying the relative importance of predictors of survival in out of hospital cardiac arrest: a machine learning study

Introduction

Studies examining the factors linked to survival after out of hospital cardiac arrest (OHCA) have either aimed to describe the characteristics and outcomes of OHCA in different parts of the world, or focused on certain factors and whether they were associated with survival. Unfortunately, this approach does not measure how strong each factor is in predicting survival after OHCA.

Aim

To investigate the relative importance of 16 well-recognized factors in OHCA at the time point of ambulance arrival, and before any interventions or medications were given, by using a machine learning approach that implies building models directly from the data, and arranging those factors in order of importance in predicting survival.

Methods

Using a data-driven approach with a machine learning algorithm, we studied the relative importance of 16 factors assessed during the pre-hospital phase of OHCA. We examined 45,000 cases of OHCA between 2008 and 2016.

Results

Overall, the top five factors to predict survival in order of importance were: initial rhythm, age, early Cardiopulmonary Resuscitation (CPR, time to CPR and CPR before arrival of EMS), time from EMS dispatch until EMS arrival, and place of cardiac arrest. The largest difference in importance was noted between initial rhythm and the remaining predictors. A number of factors, including time of arrest and sex were of little importance.

Conclusion

Using machine learning, we confirm that the most important predictor of survival in OHCA is initial rhythm, followed by age, time to start of CPR, EMS response time and place of OHCA. Several factors traditionally viewed as important, e.g. sex, were of little importance.

Dispatcher Identification of Out-of-Hospital Cardiac Arrest and Neurologically Intact Survival: A Retrospective Cohort Study

Introduction:

To date, there are no published data on the association of patient-centered outcomes and accurate public-safety answering point (PSAP) dispatch in an American population. The goal of this study is to determine if PSAP dispatcher recognition of out-of-hospital cardiac arrest (OHCA) is associated with neurologically intact survival to hospital discharge.

Methods:

This retrospective cohort study is an analysis of prospectively collected Quality Assurance/Quality Improvement (QA/QI) data from the San Antonio Fire Department (SAFD; San Antonio, Texas USA) OHCA registry from January 2013 through December 2015. Exclusion criteria were: Emergency Medical Services (EMS)-witnessed arrest, traumatic arrest, age <18 years old, no dispatch type recorded, and missing outcome data. The primary exposure was dispatcher recognition of cardiac arrest. The primary outcome was neurologically intact survival (defined as Cerebral Performance Category [CPC] 1 or 2) to hospital discharge. The secondary outcomes were: bystander cardiopulmonary resuscitation (CPR), automated external defibrillator (AED) use, and prehospital return of spontaneous return of circulation (ROSC).

Results:

Of 3,469 consecutive OHCA cases, 2,569 cases were included in this analysis. The PSAP dispatched 1,964/2,569 (76.4%) of confirmed OHCA cases correctly. The PSAP dispatched 605/2,569 (23.6%) of confirmed OHCA cases as another chief complaint. Neurologically intact survival to hospital discharge occurred in 99/1,964 (5.0%) of the recognized cardiac arrest group and 28/605 (4.6%) of the unrecognized cardiac arrest group (OR = 1.09; 95% CI, 0.71–1.70). Bystander CPR occurred in 975/1,964 (49.6%) of the recognized cardiac arrest group versus 138/605 (22.8%) of the unrecognized cardiac arrest group (OR = 3.34; 95% CI, 2.70–4.11).

Conclusion:

This study found no association between PSAP dispatcher identification of OHCA and neurologically intact survival to hospital discharge. Dispatcher identification of OHCA remains an important, but not singularly decisive link in the OHCA chain of survival.

[Degree of implementation of structured answering of emergency calls in German emergency dispatch centers and effects of the introduction in daily practice]

BACKGROUND

The emergency call-taking process is crucial for the adequate disposition of emergency vehicles and the provision of first aid instructions. Moreover, it has a direct impact on the quality of out-of-hospital emergency care. Organizations such as the European Resuscitation Council, the German Federal Association of Emergency Medical Directors and the German Association of Emergency Dispatch Centers call for the nationwide implementation of a formal call-taking process in emergency dispatching. This is required for the provision of telephone-assisted cardiopulmonary resuscitation (T-CPR).

METHODS

This article presents the results of an online survey among members of the German Association of Emergency Dispatch Centers on the implementation of structured call-taking programs. The survey comprised data on the implementation of a structured call-taking process, its effects on important quality indicators such as the frequency of T‑CPR and employee satisfaction.

RESULTS

Of the 100 participants who completed the survey, 49 already used formal call-taking systems and 24 (47%) of the remaining 51 emergency dispatch centers intended to implement such a system. Formal call-taking systems were mainly used in the dispatch of emergency medical services (98% of emergency dispatch centers using a formal call-taking system) and fire brigades (83.7% of emergency dispatch centers using a formal call-taking system). In 42 (85.7%) of the 49 emergency dispatch centers using a formal call-taking process, this process is mandatory; however, only 27 (64.3%) reported compliance rates of more than 95% in medical emergencies. Comparing the pre-post results after the introduction of a structured approach, the quality of the inquiries improved for almost all emergency dispatch centers. On the other hand, important quality indicators, e.g. mean dispatch initiation time or the necessity of subsequently alerting an advanced life support unit to the scene, were not recorded in 42.9% and 49.0% of the dispatch centers, respectively. Of the emergency dispatch centers that analyzed the frequency of T‑CPR, 94.3% could show an increase in T‑CPR. Moreover, 79.5% of the respondents reported improved employee satisfaction. Whereas the demand for dispatchers remained nearly static, 24 out of the 49 dispatch centers that used a formal call-taking system set up new posts for quality management (maximum: 3 posts in dispatch centers handling more than 250,000 missions annually).

CONCLUSION

Structured emergency call-taking has not yet been comprehensively implemented in German emergency dispatch centers. Wherever it is used consistently, important quality parameters are improved. Further investigations should aim to identify crucial factors for its implementation and to analyze additional quality parameters.

Machine learning as a supportive tool to recognize cardiac arrest in emergency calls

BACKGROUND

Emergency medical dispatchers fail to identify approximately 25% of cases of out of hospital cardiac arrest, thus lose the opportunity to provide the caller instructions in cardiopulmonary resuscitation. We examined whether a machine learning framework could recognize out-of-hospital cardiac arrest from audio files of calls to the emergency medical dispatch center.

METHODS

For all incidents responded to by Emergency Medical Dispatch Center Copenhagen in 2014, the associated call was retrieved. A machine learning framework was trained to recognize cardiac arrest from the recorded calls. Sensitivity, specificity, and positive predictive value for recognizing out-of-hospital cardiac arrest were calculated. The performance of the machine learning framework was compared to the actual recognition and time-to-recognition of cardiac arrest by medical dispatchers.

RESULTS

We examined 108,607 emergency calls, of which 918 (0.8%) were out-of-hospital cardiac arrest calls eligible for analysis. Compared with medical dispatchers, the machine learning framework had a significantly higher sensitivity (72.5% vs. 84.1%, p < 0.001) with lower specificity (98.8% vs. 97.3%, p < 0.001). The machine learning framework had a lower positive predictive value than dispatchers (20.9% vs. 33.0%, p < 0.001). Time-to-recognition was significantly shorter for the machine learning framework compared to the dispatchers (median 44 seconds vs. 54 s, p < 0.001).

CONCLUSIONS

A machine learning framework performed better than emergency medical dispatchers for identifying out-of-hospital cardiac arrest in emergency phone calls. Machine learning may play an important role as a decision support tool for emergency medical dispatchers.

We need to include bystander first aid in trauma research

Background

The chain of trauma survival is a concept that originated in the area of out-of-hospital cardiac arrest (OHCA) and was adapted to the treatment of trauma. In out-of-hospital cardiac arrest research into bystander first aid has resulted in improved outcome. Whereas, in trauma research the first link of the chain of survival is almost ignored.

Methods

In OHCA, cardiopulmonary resuscitation (CPR) from bystanders has been subject of a vast amount of research, as well as measures and programs to raise the rate of bystander CPR to cardiac arrest victims. These efforts have resulted in improved survival. The research effort has been well grounded in the research community, as demonstrated by its natural inclusion in the uniform reporting template (Utstein) for the treatment of OHCA. In trauma the bystander may contribute by providing an open airway, staunch bleedings, or prevent hypothermia. In trauma however, while the chain of survival has been adopted along with it distinct links, including bystander first aid, the consensus-based uniform reporting template for trauma (the Utstein template) does not include the bystander first aid efforts. There is extremely little research on what first aid measures bystanders provide to trauma victims, and on what impact such measures have on outcome. An important step to improve research on bystander first aid in trauma would be to include this as part of the uniform reporting template for trauma

Conclusion

The lack of research on bystander first aid makes the first link in the trauma chain of survival the weakest link. We, the trauma research community, should either improve our research and knowledge in this area, or remove the link from the chain of survival

Effect and accuracy of emergency dispatch telephone guidance to bystanders in trauma: post-hoc analysis of a prospective observational study

BACKGROUND

Emergency medical communication centres (EMCCs) dispatch and allocate ambulance resources, and provide first-aid guidance to on-scene bystanders. We aimed to 1) evaluate whether dispatcher guidance improved bystander first aid in trauma, and 2) to evaluate whether dispatchers and on-scene emergency medical services (EMS) crews identified the same first aid measures as indicated.

METHODS

For 18 months, the crew on the first EMS crew responding to trauma calls used a standard form to assess bystander first aid. Audio recordings of the corresponding telephone calls from bystanders to the EMCC were reviewed.

RESULTS

A total of 311 trauma calls were included. The on-scene EMS crew identified needs for the following first-aid measures: free airway in 26 patients, CPR in 6 patients, and hypothermia prevention in 179 patients. EMCC dispatchers advised these measures, respectively, in 16 (62%), 5 (83%), and 54 (30%) of these cases. Dispatcher guidance was not correlated with correctly performed bystander first aid. For potentially life saving first aid measures, all (20/20) callers who received dispatcher guidance attempted first aid, while only some few (4/22) of the callers who did not receive dispatcher guidance did not attempt first aid.

DISCUSSION

Overall, the EMCC dispatchers had low sensitivity and specificity for correctly identifying trauma patients requiring first-aid measures. Dispatcher guidance did not significantly influence whether on-scene bystander first aid was performed correctly or attempted in this study setting, with a remarkably high willingness to perform first-aid. However, the findings for potentially lifesaving measures suggests that there may be differences that this study was unable to detect.

CONCLUSION

This study found a high rate of first-aid willingness and performance, even without dispatcher prompting, and a low precision in dispatcher advice. This underlines the need for further knowledge about how to increase EMCC dispatchers' possibility to identify trauma patients in need of first aid. The correlation between EMCC-guidance and bystander first aid should be investigated in study settings with lower spontaneous first-aid rates.

Targeted simulation and education to improve cardiac arrest recognition and telephone assisted CPR in an emergency medical communication centre

AIM

Recognition of cardiac arrest and prompt activation time by emergency medical dispatch are key process measures that have been associated with improved survival after out-of-hospital cardiac arrest (OHCA). The aim of this study is to improve recognition of OHCA and time to initiation of telephone assisted chest compressions in an emergency medical communication centre (EMCC).

METHODS

A prospective, interventional study implementing targeted interventions in an EMCC. Interventions included: (1) lectures focusing on agonal breathing and interrogation strategy (2) simulation training (3) structured dispatcher feedback (4) web-based telephone assisted CPR training program. All ambulance-confirmed OHCA calls in the study period were assessed and relevant process and result measures were recorded pre- and post-intervention. Cardiac arrest was reported as (1) recognised, (2) not recognised or (3) delayed recognition.

RESULTS

We included 331 and 230 calls pre- and post-intervention, respectively. Recognition of cardiac arrest improved significantly after intervention (89 vs. 95%, p=0.024). Delayed recognition was significantly reduced (21 vs. 6%, p>0.001), as was misinterpretation of agonal breathing (25 vs. 10%, p<0.001). Telephone assisted compressions increased (71% vs. 83%, p=0.002) whereas bystander performed ventilations decreased after intervention (23% vs. 15%, p=0.016). Time intervals for initiation of chest compression instructions (2.6 vs. 2.3min, p=0.042) and delivery of telephone assisted chest compressions (3.3 vs. 2.8min, p=0.015) were significantly shortened after intervention.

CONCLUSION

Targeted simulation, education and feedback significantly improved recognition of OHCA and reduced time to first chest compression. Continuous measurement of key quality metrics can facilitate development of targeted education and training.

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.

Factors impacting upon timely and adequate allocation of prehospital medical assistance and resources to cardiac arrest patients

AIM

Explore, understand and address issues that impact upon timely and adequate allocation of prehospital medical assistance and resources to out-of-hospital cardiac arrest (OHCA) patients.

METHODS

Mixed-methods design obtaining data for one year in three emergency medical communication centres (EMCC); Oslo-Akershus (OA), Vestfold-Telemark (VT) and Østfold (Ø). Data collection included quantitative data from analysis of dispatch logs, ambulance records and audio files. Qualitative data were collected through in-depth interviews and non-participant observations.

RESULTS

OA-, VT- and Ø-EMCC responded to 1095 OHCAs and 579 of these calls were included for further analysis (333, 143 and 103, respectively). There were significant site differences in their recognition of OHCA (89, 94 and 78%, respectively, p<0.001), provision of CPR instructions (83, 83 and 61%, respectively, p<0.001), time from call answered to initial CPR instructions (1.4min (1.2, 1.6), 1.1min (0,9, 1.2) and 1.3 (1.2, 1.7) respectively, p=0.002). The most frequent reason for delayed or failed recognition of OHCA was misinterpretation of agonal breathing. Interviews and observations revealed individual differences in protocol use, interrogation strategy and assessment of breathing. Use of protocol was only part of decision making, dispatchers trusted their own clinical experience and intuition, and used assumptions about the patient and the situation as part of decision making.

CONCLUSION

Agonal breathing continues to be the main barrier to recognition of cardiac arrest. Individual differences among dispatchers' strategies can directly impact on performance, mainly due to the wide definition of cardiac arrest and lack of uniform tools for assessment of breathing.

Dispatch guideline adherence and response interval-a study of emergency medical calls in Norway

Background

The Emergency Medical Communication Centre (EMCC) operators in Norway report using the Norwegian Index for Medical Emergency Assistance (Index), a criteria-based dispatch guideline, in about 75 % of medical emergency calls. The main purpose of a dispatch guideline is to assist the operator in securing a correct response as quickly as possible. The effect of using the guideline on EMCC response interval is as yet unknown. We wanted to ascertain an objective measure of guideline adherence, and explore a possible effect on emergency medical dispatch (EMD) response interval.

Methods

Observational cross-sectional study based on digital telephone recordings and EMCC records; 299 random calls ending in acute and urgent responses from seven strategically selected EMCCs were included. Ability to confirm location and patient consciousness within an acceptable time interval and structural use of criteria cards were indicators used to create an overall guideline adherence variable. We then explored the relationship between different levels of guideline adherence and EMD response interval.

Results

The overall guideline adherence was 80 %. Location and patient consciousness were confirmed within 1 min in 83 % of the calls. The criteria cards were used systematically as intended in 64 % of the cases. Total median response interval was 2:28, with 2:01 for acute calls and 4:10 for urgent calls (p < 0.0005). Lower guideline adherence was associated with higher EMD response interval (p < 0.0005).

Conclusion

The measured guideline adherence was higher than previously reported by the operators themselves. Patient consciousness was rapidly confirmed in the majority of cases. Failure to use Index criteria as intended result in delayed ambulance dispatch and a potential risk of undertriage.

Electronic supplementary material

The online version of this article (doi:10.1186/s12873-016-0105-2) contains supplementary material, which is available to authorized users.

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.

Non-urgent Emergency Callers: Characteristics and Prognosis

OBJECTIVE

In Denmark, calls to the Danish emergency number 1-1-2 concerning medical emergencies are received by an emergency medical communication center (EMCC). At the EMCC, health care professionals (nurses, paramedics, and physicians) decide the necessary response, depending on the level of emergency as indicated by the Danish Index for Emergency Care. The index states 37 main criteria (symptoms) and five levels of emergency, descending from A (life threatening) to E (not serious). An ambulance is not sent to emergency level-E patients (level-E patients), but they are given other kinds of help/advice. No prior studies focusing on Danish level-E patients exist, hence the sparse knowledge about them. This study aimed to characterize level-E patients in the Central Denmark Region and to investigate their progress in the health care system after the 1-1-2 call, regarding contacting 1-1-2 again, general practitioner and Emergency Department (ED) visits, hospital admission, and death.

METHODS

This is a retrospective follow-up study of callers who contacted the EMCC of the Central Denmark Region and were assessed as level-E patients from August 2013 to July 2014. The study population was identified in the EMCC dispatch software, whose data were supplemented with health care data from three national registries.

RESULTS

Of the 53,414 patients who called 1-1-2 over the study period, 4,962 level-E patients were included in the study. The median age was 47 years (IQR: 24.3-67.7), and 53.4% were men. The most common main criteria were extremity pain - minor wounds. Within 1 day after their 1-1-2 call, 42.1% had a subsequent contact with the health care system. Of those, 5.9% called 1-1-2 again, 24.3% contacted an ED, and 8.6% were admitted. The fatality rate was 0.1%.

CONCLUSIONS

Level-E patients who contacted the EMCC of the Central Denmark Region were most frequently young adults. Almost 60% of level E-patients, who could be tracked, had no further contact with the health care system within a day after their 1-1-2 call. Of those who did, a quarter contacted an ED, indicating that level-E patients needed medical attention. The low fatality rates suggest limited undertriage, that is, level-E patients do not seem to need emergency medical service transportation. Further studies on undertriage among other things are needed.

Does the Norwegian emergency medical dispatch classification as non-urgent predict no need for pre-hospital medical treatment? An observational study

Background

The number of ambulance call-outs in Norway is increasing owing to societal changes and increased demand from the public. Together with improved but more expensive education of ambulance staff, this leads to increased costs and staffing shortages. We wanted to study whether the current dispatch triage tools could reliably identify patients who only required transport, and not pre-hospital medical care. This could allow selection of such patients for designated transport units, freeing up highly trained ambulance staff to attend patients in greater need.

Methods

A cross-sectional observational study was used, drawing on all electronic and paper records in our ambulance service from four random days in 2012. The patients were classified into acuity groups, based on Emergency Medical Dispatch codes, and pre-hospital interventions were extracted from the Patient Report Forms.

Results

Of the 1489 ambulance call-outs included in this study, 82 PRFs (5 %) were missing. A highly significant association was found between acuity group and recorded pre-hospital intervention (p ≤ 0.001). We found no correlation between gender, distance to hospital, age and pre-hospital interventions. Ambulances staffed by paramedics performed more interventions (234/917, 26 %) than those with emergency medical technicians (42/282, 15 %). The strongest predictor for needing pre-hospital interventions was found to be the emergency medical dispatch acuity descriptor.

Discussion

This study has demonstrated that the Norwegian dispatch system is able to correctly identify patients who do not need pre-hospital interventions. Patients with a low acuity code had a very low level of pre-hospital interventions. Evaluation of adherence to protocol in the Emergency Medical Dispatch is not possible due to the inherent need for medical experience in the triage process.

Conclusions

This study validates the Norwegian dispatch tool (Norwegian index) as a predictor of patients who do not need pre-hospital interventions.

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.

Time to identify cardiac arrest and provide dispatch-assisted cardio-pulmonary resuscitation in a criteria-based dispatch system

INTRODUCTION

Dispatch-assisted cardiopulmonary resuscitation (DA-CPR) plays a key role in out-of-hospital cardiac arrests. We sought to measure dispatchers' performances in a criteria-based system in recognizing cardiac arrest and delivering DA-CPR. Our secondary purpose was to identify the factors that hampered dispatchers' identification of cardiac arrests, the factors that prevented them from proposing DA-CPR, and the factors that prevented bystanders from performing CPR.

METHODS AND RESULTS

We reviewed dispatch recordings for 1254 out-of-hospital cardiac arrests occurring between January 1, 2011 and December 31, 2013. Dispatchers correctly identified cardiac arrests in 71% of the reviewed cases and 84% of the cases in which they were able to assess for patient consciousness and breathing. The median time to recognition of the arrest was 60s. The median time to start chest compression was 220s.

CONCLUSIONS

This study demonstrates that performances from a criteria-based dispatch system can be similar to those from a medical-priority dispatch system regarding out-of-hospital cardiac arrest (OHCA) time recognition and DA-CPR delivery. Agonal breathing recognition remains the weakest link in this sensitive task in both systems. It is of prime importance that all dispatch centers tend not only to implement DA-CPR but also to have tools to help them reach this objective, as today it should be mandatory to offer this service to the community. In order to improve benchmarking opportunities, we completed previously proposed performance standards as propositions.