Dispatcher Assistance Research Articles

Online training to improve BLS performance with dispatcher assistance? Results of a cluster-randomised controlled simulation trial

BackgroundThe prognosis for patients improves significantly with effective cardiopulmonary resuscitation (CPR) performed by bystanders. Current research indicates that individuals who receive CPR from trained bystanders have a greater likelihood of survival compared to those who receive dispatcher-assisted CPR from untrained laypersons. This cluster-randomised controlled trial assessed the impact of a 30-min online training session prior to a simulated cardiac arrest situation with dispatcher-assisted CPR (DA-CPR) on enhancing Basic Life Support (BLS) performance.MethodsThis study was performed in 2018 in Hamburg, Germany. The primary outcome was the practical BLS skills of high school students in simulated out-of-hospital cardiac arrest scenarios with dispatcher assistance. The intervention group participants underwent a 30-min online BLS training session, while the control group did not receive an intervention. It was hypothesized that the average practical BLS scores of the intervention group would be 1.5 points higher than those of the control group.ResultsBLS assessments of 286 students of 16 different classes were analysed. The estimated mean BLS score in the intervention group was 7.60 points (95% CI: 6.76 to 8.44) compared to 6.81 (95% CI: 5.97 to 7.65) in the control group adjusted for BLS training and class. Therefore, the estimated mean difference between the groups was 0.79 (95% CI: -0.40 to 1.97) and not significantly different (p-value: 0.176). Based on a logistic regression analysis the intervention had only a significant effect on the chance to pass the item “vertically above the chest” (OR = 4.99; 95% CI: 1.46 to 17.12) adjusted for BLS training and class.ConclusionPrior online training exhibits beneficial impacts on the BLS performance of bystanders during DA-CPR. To maximise the effect size, online training should be incorporated into a set of interventions that are mutually complementary and specifically designed for the target participants.Trial registrationDRKS00033531. "Kann online Training Laien darauf vorbereiten Reanimationsmaßnahmen unter Anleitung der Leitstelle adäquat durchzuführen? " Registered on January 29, 2024.

Foreign Body Airway Obstruction: Modern Principles and Approaches to First Aid and Dispatcher Assistance on First Aid

Foreign body airway obstruction (FBAO) is one of the most common causes of accidental death in adults and children. Probability of saving a life in severe FBAO depends on the ability of the bystander to quickly recognize the problem and correctly provide first aid (FA) to the victim. However, due to the lack of knowledge and skills of the FA, bystanders rarely attempt to give necessary help. Along with mass FA training, provision of instructions on the FA to untrained bystanders over the telephone by emergency medical services (EMS) dispatchers can facilitate active involvement of the population in the process of providing FA. In this study, a detailed analysis of the modern principles and approaches to the provision of the FA in FBAO was carried out and a draft of a universal Russian-language algorithm for remote dispatch support of the FA was developed. The developed algorithm can become a component of the domestic program for remotely instructing the population on provision of FA in life-threatening conditions and is proposed for further testing and implementation in the practice of EMS dispatchers.

Dispatcher-assisted BLS for lay bystanders: A pilot study comparing video streaming via smart glasses and telephone instructions

ObjectiveTo determine whether dispatcher assistance via smart glasses improves bystander basic life support (BLS) performance compared with standard telephone assistance in a simulated out-of-hospital cardiac arrest (OHCA) scenario. MethodsPilot study in which 28 lay people randomly assigned to a smart glasses-video assistance (SG-VA) intervention group or a smartphone-audio assistance (SP-AA) control group received dispatcher guidance from a dispatcher to provide BLS in an OHCA simulation. SG-VA rescuers received assistance via a video call with smart glasses (Vuzix, Blade) connected to a wireless network, while SP-AA rescuers received instructions over a smartphone with the speaker function activated. BLS protocol steps, quality of chest compressions, and performance times were compared. ResultsNine of the 14 SG-VA rescuers correctly completed the BLS protocol compared with none of the SP-AA rescuers (p = 0.01). A significantly higher number of SG-VA rescuers successfully opened the airway (13 vs. 5, p = 0.002), checked breathing (13 vs. 8, p = 0.03), correctly positioned the automatic external defibrillator pads (14 vs.6, p = 0.001), and warned bystanders to stay clear before delivering the shock (12 vs. 0, p < 0.001). No significant differences were observed for performance times or chest compression quality. The mean compression rate was 104 compressions per minute in the SG-VA group and 98 compressions per minute in the SP-AA group (p = 0.46); mean depth of compression was 4.5 cm and 4.4 cm (p = 0.49), respectively. ConclusionsSmart glasses could significantly improve dispatcher-assisted bystander performance in an OHCA event. Their potential in real-life situations should be evaluated.

Impact of the COVID-19 pandemic on prehospital characteristics and outcomes of out-of-hospital cardiac arrest among the elderly in Japan: A nationwide study

AimTo assess the impact of the 2020 coronavirus disease (COVID-19) pandemic on the prehospital characteristics and outcomes of out-of-hospital cardiac arrest (OHCA) in the elderly. MethodsIn this population-based nationwide observational study in Japan, 563,100 emergency medical service-unwitnessed OHCAs in elderly (≥65 years) patients involving any prehospital resuscitation efforts were analysed (144,756, 140,741, 140,610, and 136,993 cases in 2020, 2019, 2018, and 2017, respectively). The epidemiology, characteristics, and outcomes associated with OHCAs in elderly patients were compared between 3 years pre-pandemic (2017–2019) and the pandemic year (2020). The primary outcome was neurologically favourable one-month survival. The secondary outcomes were the rate of bystander cardiopulmonary resuscitation (CPR), defibrillation by a bystander, dispatcher-assisted (DA)-CPR attempts, and one-month survival. ResultsDuring the pandemic year, the rates of neurologically favourable 1-month survival (crude odds ratio, 95% confidence interval: 1.19, 1.14–1.25), bystander CPR (1.04, 1.03–1.06), and DA-CPR attempts (1.10, 1.08–1.11) increased, whereas the incidence of public access defibrillation (0.88, 0.83–0.93) decreased. Subgroup analyses based on interaction tests showed that the increased rate of neurologically favourable survival during the pandemic year was enhanced in OHCA at care facilities (1.51, 1.36–1.68) and diminished or abolished on state-of-emergency days (0.90, 0.74–1.09), in the mainly affected prefectures (1.08, 1.01–1.15), and in cases with shockable initial rhythms (1.03, 0.96–1.12). ConclusionsThe COVID-19 pandemic increased the bystander CPR rate in association with enhanced DA-CPR attempts and improved the outcomes of elderly patients with OHCAs.

Distance assistance for first aid in trauma: literature review and a draft of the dispatcher algorithm

Being a common cause of death and disability, injuries remain a highly relevant global public health problem. In Russia, injuries hold one of the leading positions in the structure of mortality of the population, causing significant social and economic losses for the country. While the likelihood of saving lives and preventing severe complications in injuries largely depends on the ability of witnesses of the incident to early and correctly provide first aid (FA) to the victims, the actual frequency of providing FA remains low. A promising way to involve untrained people in the process of providing FA is to remotely instruct witnesses of the incident by emergency dispatchers on how to give FA. This article discusses international experience of dispatcher assistance for FA in trauma and presents a draft of a universal Russian-language algorithm for remote dispatcher interviewing and advising witnesses of the incident on provision of FA in trauma, that was developed taking into account the current Russian and international guidelines. The algorithm is proposed for further appraisal and implementation in the practical work of emergency dispatchers as a basic component of the federal program of dispatcher assistance for FA.

Dispatcher Assistance Worsened Outcomes of Unwitnessed Out-of Hospital Cardiac Arrest: An Observational Study with Component Analysis of Rescue Breath Combination and Dispatcher Assistance

Objectives: This study aimed to analyze the effects of combinations of rescue breathing and chest compression in CPR performed by a bystander (BCPR) on the outcomes of out-of-hospital cardiac arrest (OHCA) events. Particular attention was paid to unwitnessed case by bystander. Methods: This retrospective study analyzed the prospectively collected data of 212,003 unwitnessed and 117,920 bystander-witnessed OHCA cases between 2014 and 2016 in Japan. BCPR classification was based on two clinical components: whether or not DA was provided, and whether standard CPR (with breaths) or compression-only CPR was performed. Main Outcome Measures: A neurologically favorable outcome at one month. Results: Univariate analysis showed that, in unwitnessed cases, there was no significant association between the provision of BCPR and a neurologically favorable outcome (BCPR vs. no-BCPR: 0.65% (686/106,152) vs. 0.66% (694/105,851)). In bystander-witnessed cases, the rates were 5.6% (3,538/62,814) vs. 3.5% (1,911/55,106). After classifying BCPR according to the two clinical components, the outcomes of unwitnessed cases were improved for standard BCPR with DA and compression-only, for standard BCPR without DA, but not for compression-only BCPR with DA. Multivariate logistic regression analysis focusing on the two clinical components in unwitnessed BCPR cases showed worse neurologically favorable outcomes with DA provision but better outcomes for standard BCPR, without significant interaction. In bystanderwitnessed cases, DA provision was associated with better outcomes, with significant interaction. Conclusions: Compared with no-BCPR, compression-only BCPR with DA does not improve neurologically favorable outcomes. Standard BCPR without DA resulted in the best outcomes in unwitnessed OHCA cases.

Neural Network Training in an Automated Dispatcher Problem

The application of artificial intelligence in the development of а decision support system for the implementation of transport traffic is presented. Such systems are designed to adjust the schedule of objects in cases of unforeseen situations. A fully connected artificial neural network with several hidden layers, trained using a genetic algorithm, is used. During training, the functionality that characterizes the deviation from the specified schedule is minimized. Railway traffic is one of the most important types of transport in Russia. Every year it becomes more and more intense, the density and volume of both cargo and passenger traffic increases. As a result, the requirements for the exact execution of the planned traffic schedule increase, since any deviation leads to significant penalties due, for example, to an increase in train delays, their cancellation, etc. The work of a dispatcher, a person who controls railway traffic, is quite time-consuming and becomes more difficult every day, so the development of dispatcher assistance systems is one of the most relevant areas in control automation in this area. At the same time, the existing high requirements for traffic safety, which impose additional restrictions, finally lead to the fact that in this kind of system, the final decision is left to the person, and computer development has a recommendatory character. This article describes the artificial intelligence apparatus in the form of training neural networks using a genetic algorithm to build an automated dispatcher that corrects movement.

Dispatcher-Assisted Cardiopulmonary Resuscitation — Influence on Return of Spontaneous Circulation and Short-Term Survival

The Aim: analysis of the influence of dispatcher assistance during cardiopulmonary resuscitation (CPR) of patients with out-of-hospital cardiac arrest (OHCA) in achieving return of spontaneous circulation (ROSC), better survival at the scene, survival to discharge, and 30-day survival.Materials and methods. This study includes epidemiological data on OHCA collected by the study protocol of the European Resuscitation Council's EuReCa_ONE study during the period October 1, 2014 — December 31, 2019. Statistical analysis was performed using SPSS Statistics v26 and GraphPad Prism v8 software packages.Results. This study included 288 patients with OHCA where CPR was provided by bystander. Dispatcher-assisted CPR (DA-CPR) occurred in 56.9% of those patients and ROSC was achieved in 31.3% of cases. Forty-four patients were hospitalized and 16 of those survived until discharge. There was no influence of dispatcher assistance on ROSC, although it resulted in slightly greater risk of the absence of ROSC (OR=1.063). Higher mortality rate to discharge occurred in DA-CPR group (P=0.013). No statistical significance was observed between DA-CPR and non-DA-CPR groups in terms of death at the scene, and 30-day survival. Dispatcher assistance during the initial CPR in hospitalized OHCA patients was a significant predictor of death outcome during hospitalization (P=0.017, OR=5.500).Conclusions. There is no significant association between the presence/absence of dispatcher assistance and ROSC or 30-day survival rate. In contrast, DA-CPR was non-significantly associated with slightly higher odds for the absence of ROSC. DA-CPR was also associated with lower survival-to-discharge rates in hospitalized OHCA patients. The study findings are the base/ground which highlights the need of implementation of existing and development of new guidelines regarding high-quality professional training of EMS dispatchers as well as basic life support education of general population.

Association of dispatcher-assisted cardiopulmonary resuscitation with initial shockable rhythm and survival after out-of-hospital cardiac arrest.

Bystander cardiopulmonary resuscitation (CPR) and initial shockable rhythm are crucial predictors of survival after out-of-hospital cardiac arrest (OHCA). However, the relationship between dispatcher-assisted CPR (DA-CPR) and initial shockable rhythm is not completely elucidated. To examine the association of DA-CPR with initial shockable rhythm and outcomes. This nationwide population-based observational study conducted in Japan included 59 688 patients with witnessed OHCA of cardiac origin after excluding those without bystander CPR. Patients were divided into DA-CPR (n = 42 709) and CPR without dispatcher assistance (unassisted CPR, n = 16 979) groups. The primary outcome measure was initial shockable rhythm, and secondary outcome measures were 1-month survival and neurologically intact survival. A Cox proportional hazards model adjusted for collapse-to-first-rhythm-analysis time and multivariable logistic regression models were used after propensity score (PS) matching to compare the incidence of initial shockable rhythm and outcomes, respectively. Among all patients (mean age 76.7 years), the rates of initial shockable rhythm, 1-month survival and neurologically intact survival were 20.8, 10.7 and 7.0%, respectively. The incidence of initial shockable rhythm in the DA-CPR group (20.4%, 3462/16 979) was significantly higher than that in the unassisted CPR group (18.5%, 3133/16 979) after PS matching (P < 0.0001). However, no significant differences were found between the two groups with respect to the incidence of initial shockable rhythm in the Cox proportional hazards model [adjusted hazard ratio of DA-CPR for initial shockable rhythm compared with unassisted CPR, 0.99; 95% confidence interval (CI), 0.97-1.02, P = 0.56]. No significant differences were observed in the survival rates in the two groups after PS matching [10.8% (1833/16 979) vs. 10.3% (1752/16 979), P = 0.16] and neurologically intact survival rates [7.3% (1233/16 979) vs. 6.8% (1161/16 979), P = 0.13]. The multivariable logistic regression model showed no significant differences between the groups with regard to survival (adjusted odds ratio of DA-CPR compared with unassisted CPR: 1.00; 95% CI, 0.89-1.13, P = 0.97) and neurologically intact survival (adjusted odds ratio: 1.12; 95% CI, 0.98-1.29, P = 0.14). DA-CPR after OHCA had the same independent association with the likelihood of initial shockable rhythm and 1-month meaningful outcome as unassisted CPR.

The effect of video-instructed versus audio-instructed dispatcher-assisted cardiopulmonary resuscitation on patient outcomes following out of hospital cardiac arrest in Seoul

We aimed to investigate whether video-instructed dispatcher-assisted (DA)-cardiopulmonary resuscitation (CPR) improved neurologic recovery and survival to discharge compared to audio-instructed DA-CPR in adult out-of-hospital cardiac arrest (OHCA) patients in a metropolitan city with sufficient experience and facilities. A retrospective cohort study was conducted for adult bystander-witnessed OHCA patients administered DA-CPR due to presumed cardiac etiology between January 1, 2018 and October 31, 2019 in Seoul, Korea. The primary and secondary outcomes were the differences in favorable neurologic outcome and survival to discharge rates in adult OHCA patients in the two instruction groups. Binary logistic regression analysis was performed to identify the outcome predictors after DA-CPR. A total of 2109 adult OHCA patients with DA-CPR were enrolled. Numbers of elderly patients in audio instruction and video instruction were 1260 (73.2%) and 214 (55.3%), respectively. Elderly patients and those outside the home or medical facility were more likely to receive video instruction. Favorable neurologic outcome was observed more in patients who received video-instructed DA-CPR (n = 75, 19.4%) than in patients who received audio-instructed DA-CPR (n = 117, 6.8%). The survival to discharge rate was also higher in video-instructed DA-CPR (n = 105, 27.1%) than in audio-instructed DA-CPR (n = 211, 12.3%). Video-instructed DA-CPR was significantly associated with neurologic recovery (aOR = 2.11, 95% CI 1.48–3.01) and survival to discharge (aOR = 1.81, 95% CI 1.33–2.46) compared to audio-instructed DA-CPR in adult OHCA patients after adjusting for age, gender, underlying diseases and CPR location. Video-instructed DA-CPR was associated with favorable outcomes in adult patients with OHCA in a metropolitan city equipped with sufficient experience and facilities.

Video-assisted cardiopulmonary resuscitation: Does the camera perspective matter? A randomized, controlled simulation trial

Background Dispatcher assistance can help to save lives during layperson cardiopulmonary resuscitation during cardiac arrest. The aim of this study was to investigate the influence of different camera positions on the evaluation of cardiopulmonary resuscitation performance during video-assisted cardiopulmonary resuscitation. Methods For this randomized, controlled simulation trial, seven video sequences of cardiopulmonary resuscitation performance were recorded from three different camera positions: side, foot and head position. Video sequences showed either correct cardiopulmonary resuscitation performance or one of the six typical errors: low and high compression rate, superficial and increased compression depth, wrong hand position or incomplete release. Video sequences with different cardiopulmonary resuscitation performances and camera positions were randomly combined such that each evaluator was presented seven individual combinations of cardiopulmonary resuscitation and camera position and evaluated each cardiopulmonary resuscitation performance once. A total of 46 paramedics and 47 emergency physicians evaluated seven video sequences of cardiopulmonary resuscitation performance from different camera positions. The primary hypothesis was that there are differences in accuracy of correct assessment/error recognition depending on camera perspective. Generalized linear multi-level analyses assuming a binomial distribution and a logit link were employed to account for the dependency between each evaluator's seven ratings. Results Of 651 video sequences, cardiopulmonary resuscitation performance was evaluable in 96.8% and correctly evaluated in 74.5% over all camera positions. Cardiopulmonary resuscitation performance was classified correctly from a side perspective in 81.3%, from a foot perspective in 68.8% and from a head perspective in 73.6%, revealing a significant difference in error recognition depending on the camera perspective (p = .01). Correct cardiopulmonary resuscitation was mistakenly evaluated to be false in 46.2% over all perspectives. Conclusions Participants were able to recognize significantly more mistakes when the camera was located on the opposite side of the cardiopulmonary resuscitation provider. Foot position should be avoided in order to enable the dispatcher the best possible view to evaluating cardiopulmonary resuscitation quality.

Increasing the shockable rhythm and survival rate by dispatcher-assisted cardiopulmonary resuscitation in Japan

PurposeThis study aimed to examine the effectiveness of cardiopulmonary resuscitation (CPR) directions by dispatchers. We analysed the relationship of dispatcher-assisted bystander cardiopulmonary resuscitation (DA-BCPR) with favourable cerebral function, shockable rhythm rate, and emergency medical service (EMS) arrival time. MethodsThis nationwide study was based on CPR statistical data of out-of-hospital cardiac arrest (OHCA) patients (n=629,471) from 1 January 2011 to 31 December 2015, and included 107,669 patients with bystander-witnessed cardiogenic cardiac arrest.The primary outcome was good brain function prognosis after 1 month, while the secondary outcome was the rate of shockable rhythm on ECG at the time of EMS arrival.EMS arrival time at the site was stratified into 7min, 8−10min, and 11−20min using tertiles. Adjusted odds ratios (AORs) and 95% confidence intervals (95% CIs) were estimated using multivariate logistic regression analysis to assess the association between DA-BCPR and outcomes in each tertile. ResultsThere were 37,269 (35%), 18,109 (17%), and 52,291 (49%) patients in the DA-BCPR, Only-BCPR, and no-BCPR groups, respectively. Compared to No-BCPR, DA-BCPR was associated with favourable neurological outcomes regardless of the time from 119 call to EMS contact (AOR, 1.56, 2.01, 1.82; 95% CI, 1.43−1.71, 1.80–2.24, 1.52−2.19; ≤7min, 8–10min, and 11–20min, respectively). DA-BCPR showed association with the shockable rhythm rate upon EMS arrival regardless of the time 119 call to EMS contact (AOR, 1.30, 1.60, 1.90; 95% CI, 1.23−1.38, 1.51−1.70, 1.75–2.06; ≤7min, 8–10min, and 11–20min, respectively). ConclusionProviding dispatcher assistance with CPR to 119 callers improves the long-term outcome regardless of the patient’s age and EMS response time. Thus, encouraging dispatchers to promote BCPR is important for increasing the shockable rhythm rate and improving the brain function prognosis.

Improved Out-of-Hospital Cardiac Arrest Survival with a Comprehensive Dispatcher-Assisted CPR Program in a Developing Emergency Care System

Objective Out-of-hospital cardiac arrest (OHCA) is associated with poor survival. Studies have demonstrated improved survival with early bystander cardiopulmonary resuscitation (BCPR). This study evaluated the impact of a dispatcher-assisted CPR (DA-CPR) program on BCPR rate and outcomes of OHCA in a developing emergency medical services (EMS) system setting. Methods Data were extracted from the national cardiac arrest registry. A before-after analysis was performed between OHCA cases with cardiac etiology conveyed by EMS from April 2010–June 2012 (pre-intervention) and July 2012–December 2015 (post-intervention). Primary outcomes were survival-to-discharge/30 days post-arrest and favorable cerebral performance (Glasgow-Pittsburgh cerebral performance categories 1 and 2). Results 6365 OHCA cases were analyzed with 2129 in the pre-intervention and 4236 in the post-intervention group. In the post-intervention group, there was an increase in BCPR rates from 24.8% to 53.8% (p < 0.001), adjusted OR 3.67 (aOR; 95%CI: 3.26–4.13). OHCA outcomes also improved with survival-to-discharge rates increasing from 3.0%–4.5% (p < 0.01), aOR 2.10 (95%CI: 1.40–3.17) and favorable cerebral performance increasing from 1.6% to 2.7% (p < 0.05), aOR 2.82 (95%CI: 1.65–4.82). In patients with initial shockable rhythm, BCPR without dispatcher assistance was associated with significantly higher odds of survival-to-discharge (aOR 1.67, 95%CI: 1.06–2.64) and favorable cerebral performance (aOR 2.32, 95%CI: 1.26–4.27) compared to no BCPR. Conclusion Our study showed that a simplified DA-CPR program can be successfully implemented in a developing EMS system and can contribute to higher BCPR rate and in turn, improve OHCA survival. Future studies can examine bystanders’ characteristics and quality of the CPR performed to understand their impact on survival.

Comparison between dispatcher-assisted bystander CPR and self-led bystander CPR in out-of-hospital cardiac arrest (OHCA)

IntroductionBystander cardiopulmonary resuscitation (CPR) is an important prognostic factor for outcome in out-of-hospital cardiac arrest (OHCA). The dispatcher-assisted (DA) bystander CPR program has increased the rate of bystander CPR by targeting bystanders with a lower level of CPR training. We evaluated the effects of dispatcher-assisted bystander CPR and self-led bystander CPR. MethodsA retrospective analysis was performed using a nationwide OHCA database from 2014 to 2018. Adult EMS-treated OHCA patients with presumed cardiac origin were enrolled. OHCAs were classified into 3 groups according to the type of bystander CPR (DA bystander CPR vs. self-led bystander CPR vs. no bystander CPR) provided. The primary outcome was good neurologic recovery at hospital discharge. A multivariable logistic regression model was used to estimate the association between the type of bystander CPR and outcomes. ResultsA total of 91,557 eligible OHCA patients was enrolled in the final analysis. The proportion of patients with favorable neurologic outcomes was highest with self-led bystander CPR (9.0% for self-led bystander CPR, 5.2% for DA bystander CPR and 3.2% for no bystander CPR, p < 0.01). Self-led bystander CPR was associated with better neurological recovery than DA bystander CPR (aOR with 95% CI (DA-CPR as reference): 0.63 (0.58−0.69) for no bystander CPR, 1.28 (1.17–1.40) for self-led bystander CPR). ConclusionAlthough DA CPR was associated with better neurologic outcomes than no bystander CPR, good neurologic outcomes were most strongly associated with self-led bystander CPR.

Abstract 245: Dispatcher Assisted Cardiopulmonary Resuscitation in Patients Not in Cardiac Arrest: A Multi-Center, Observation Study

Background: Dispatcher-assisted cardiopulmonary resuscitation (DA-CPR) can increase bystander CPR rates and improve outcomes in out-of-hospital cardiac arrest (OHCA). Protocols used by dispatchers are designed to provide a quick assessment for prompt initiation of CPR. However, there are instances where non-cardiac arrest cases are falsely recognised by dispatchers to be in cardiac arrest. These patients may go on to receive chest compressions and potentially suffer from complications of unnecessary CPR, though the clinical implications of starting DA-CPR on these non-cardiac arrest cases have not been studied. Hence, the objectives of this study are to find the prevalence and clinical outcomes of DA-CPR in patients not in cardiac arrest in the Singapore population. Methods: This was a multi-center, observational study of all dispatcher-recognized cardiac arrests cases between January to December 2017 involving three tertiary hospitals in Singapore. Data was collected through audio review of dispatch calls from the national emergency ambulance service and information about patients’ clinical outcomes were prospectively collected from health records. Results: During the study period, dispatchers recognised 821 patients as having cardiac arrest. Of these, 40.0% (328/ 821) were not in cardiac arrest. 52.7% (173/ 328) of the non-cardiac arrest patients had chest compressions initiated under dispatcher assistance. No complications from chest compressions were reported. The top diagnoses of non-cardiac arrest patients found were cerebrovascular accidents (CVA), syncope and infection. A multiple logistic regression model with estimates adjusted for the presence or absence of chest compressions revealed that only final diagnoses of CVA (OR 20.68), infection (OR 17.34) and myocardial infarction (OR 32.19) were associated with in-hospital mortality. Conclusion: In this study, chest compressions initiated due to false recognition of cardiac arrest by dispatchers did not result in any reported complications and was not associated with in-hospital mortality. This provides reassurance for the continued implementation of DA-CPR.

When dispatcher assistance is not saving lives: assessment of process compliance, barriers and outcomes in out-of-hospital cardiac arrest in a metropolitan city in China

BackgroundSeveral Chinese cities have implemented dispatcher-assisted cardiopulmonary resuscitation (DA-CPR), although out-of-hospital cardiac arrest (OHCA) survival rates remain low. We aimed to assess the process compliance, barriers and outcomes of OHCA...

Dispatcher-Assisted Cardiopulmonary Resuscitation: Disparity between Urban and Rural Areas.

Methods Patients with out-of-hospital cardiac arrest (OHCA) were prospectively registered in Taichung. The 29 districts of Taichung city were divided into urban and rural areas based on whether the population density is more than 1,000 people per square kilometer. Prehospital data were collected according to the Utstein-style template, and telephone auditory records were collected by a dispatch center. Results 2,716 patients were enrolled during the study period. 88.4% OHCA occurred in urban areas and 11.6% in rural areas. 74.9% after dispatcher assistance, laypersons performed CPR in urban areas and 67.7% in rural areas (p=0.023). The proportion of laypersons continued CPR until an emergency medical technician's (EMT) arrival was higher in the urban areas (59.57% vs 52.27%, p=0.039). Laypersons continued CPR until an EMT' arrival would increase the chance of return of spontaneous circulation in urban and rural areas, with adjusted odds ratio (aOR) of 1.02, 95% confidence interval (CI) of 0.82–1.27, and aOR of 1.49, 95% CI of 0.80–2.80, respectively. Continued laypersons CPR until the EMT' arrival also improved survival with favorable neurological function, with aOR of 1.16, 95% CI of 0.61–2.20 in urban areas and aOR of 2.90 95% CI of 0.18–46.81 in rural areas. Conclusion Bystanders in urban areas exhibited higher ratio of acceptance of DACPR. However, after DACPR intervention, prognosis improvement was considerably higher in rural areas than in urban areas.

Impact of Bystander Cardiopulmonary Resuscitation and Dispatcher Assistance on Survival After Out-of-Hospital Cardiac Arrest Among Adult Patients by Location of Arrest.

We investigated the impact of bystander-initiated cardiopulmonary resuscitation (CPR), dispatcher assistance (DA), and location of arrest on survival and outcomes after out-of-hospital cardiac arrest (OHCA).From a nationwide population-based registry of OHCA patients in Japan, we enrolled adult patients with bystander-witnessed OHCA of medical origin between 2013 and 2015. The primary outcome measure was a neurologically favorable outcome, defined by cerebral performance category 1 or 2. Multivariable logistic regression analysis was used to assess the effects of bystander CPR and DA by location of arrest. A total of 104,621 cases were included (15,984 bystander CPR without DA [15.3%], 40,087 bystander CPR with DA [38.3%], and 48,550 no bystander CPR [46.4%]). In public locations, both the bystander-CPR-with-DA group (22.9% [1,068/4,665]; adjusted odds ratio (AOR), 1.62; 95% confidence interval (CI), 1.43-1.85) and the bystander-CPR-without-DA group (25.8% [918/3,557]; AOR, 1.43; 95% CI, 1.24-1.65) had neurologically favorable outcomes compared with the no-bystander-CPR group (9.9% [610/6,133]). In residential locations, the AORs were 1.44 (95% CI, 1.22-1.70) in the bystander-CPR-without-DA group and 1.60 (95% CI, 1.45-1.77) in the bystander-CPR-with-DA group. However, in nursing homes, bystander CPR was not associated with improved outcomes of OHCA, regardless of the implementation of DA.Bystander CPR with or without DA had better outcomes after OHCA in residential and public locations but not in nursing homes.

Abstract 294: Different Effect of Bystander CPR According to Dispatcher-Assistance on Neurologic Outcome in Out-Of-Hospital Cardiac Arrest

Introduction: Bystander CPR is an important prognostic factor for outcome in out-of-hospital cardiac arrest (OHCA). Dispatcher-assisted(DA) CPR program have shown to successfully increase rate of bystander CPR in communities. However DA-CPR is usually targeted for bystanders with no or lower level of CPR training compared to bystanders who are able to perform CPR without dispatcher assistance. We evaluated the effect of bystander CPR separately according to presence of dispatcher assistance on neurologic outcome. Methods: Retrospective analysis was performed using nationwide OHCA database from 2014 to 2017. Adult EMS treated OHCA with presumed cardiac origin were enrolled. EMS witnessed arrest and arrest occurred during ambulance transport were excluded. Bystander CPR was classified into 2 groups according to presence of DA-CPR instruction from emergency medical dispatch center. Rate of favorable neurologic outcome (CPC 1 or 2) was compared according to type of bystander CPR. Multivariable logistic regression model was used to estimate effect of bystander CPR type on outcomes. Results: Total of 72,314 eligible OHCA were enrolled for final analysis. Proportion of patients with favorable neurologic outcome was highest in bystander CPR without dispatcher assistance. (8.6% for bystander CPR without DA, 5.0% for bystander CPR with DA and 2.9% for no bystander CPR, p&lt;0.01). Bystander CPR with DA was associated with higher chance of good neurological recovery than no bystander CPR, effect on neurologic outcome was significantly different than bystander CPR without DA(adjusted OR with 95% CI (bystander CPR with DA as reference): 0.61[0.55-0.67] for no-bystander CPR , 1.24[1.14–1.36] for bystander CPR without DA) Conclusion: Bystander CPR with DA showed positive effect on neurologic outcome compared to no-bystander CPR. However bystander CPR with DA was less effective than bystander CPR performed without dispatcher assistance. To improve quality of bystander CPR with dispatcher assistance, strategy to monitor and give feedback bystander CPR during dispatcher assistance should be developed and implemented in dispatch center.

P4170Survival after dispatcher assisted CPR in out of hospital cardiac arrest compared to CPR without dispatcher assistance and no CPR before emergency medical services arrival – a nationwide study

Abstract Background Cardiopulmonary resuscitation (CPR) before arrival of emergency medical services (EMS) is associated with survival in out-of hospital cardiac arrest. Dispatcher assisted CPR (DA-CPR) has been shown to increase CPR rates. However there are several challenges to successful DA-CPR, such as identification of cardiac arrest, time delays to CPR instructions, time delays to start of chest compression and quality of CPR. Purpose The aim of this study is to assess survival in out of hospital cardiac arrest after no CPR, DA-CPR and CPR without dispatcher assistance before EMS arrival in a nationwide cardiac arrest register. Methods A register based observational study. All consecutive Out of Hospital Cardiac Arrests reported to the Swedish Register for Cardiopulmonary Resuscitation in 2010–2017 were collected. Patients with cardiac arrest witnessed by EMS, who received CPR by off-duty medical professionals, missing data on CPR, DA-CPR or survival were excluded. Exposure was categorized as either; no CPR before EMS arrival (NO-CPR), dispatcher assisted CPR before EMS arrival (DA-CPR) and CPR before EMS arrival without dispatcher assistance, spontaneous CPR (S-CPR). Propensity score matched cohorts were used for comparison between groups. Primary endpoint was 30-day survival. Results Out of 36309, a total of 15471 patients were included, 41.6% received NO-CPR 31.0% received DA-CPR and 27.4% received S-CPR. In propensity score matched cohorts survival to 30-days was 9.0% after NO-CPR, 13.6% after DA-CPR and 15.8% after S-CPR. Using DA-CPR as reference, NO-CPR was associated with lower survival (Conditional OR 0.61, 95% CI 0.52–0.72), absolute difference 4.6% (95% CI 3.0%-6.2%) and S-CPR was associated with higher survival (Conditional OR 1.21 (95% CI 1.05–1.39), absolute difference 2.3% (95% CI 0.5%-4.0%). 30-day survival Conclusion In this nationwide study spontaneous CPR was associated with the highest survival. When spontaneous CPR is not initiated DA-CPR is a reasonable option. Acknowledgement/Funding Swedish Heart and Lung Foundation