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

Experiences among firefighters and police officers of responding to out-of-hospital cardiac arrest in a dual dispatch programme in Sweden: an interview study

OBJECTIVES

The objective of this study was to explore firefighters' and police officers' experiences of responding to out-of-hospital cardiac arrest (OHCA) in a dual dispatch programme.

DESIGN

A qualitative interview study with semi-structured, open-ended questions where critical incident technique (CIT) was used to collect recalled cardiac arrest situations from the participants' narratives. The interviews where transcribed verbatim and analysed with inductive content analysis.

SETTING

The County of Stockholm, Sweden.

PARTICIPANTS

Police officers (n=10) and firefighters (n=12) participating in a dual dispatch programme with emergency medical services in case of suspected OHCA of cardiac or non-cardiac origin.

RESULTS

Analysis of 60 critical incidents was performed resulting in three consecutive time sequences (preparedness, managing the scene and the aftermath) with related categories, where first responders described the complexity of the cardiac arrest situation. Detailed information about the case and the location was crucial for the preparedness, and information deficits created stress, frustration and incorrect perceptions about the victim. The technical challenges of performing cardiopulmonary resuscitation and managing the airway was prominent and the need of regular team training and education in first aid was highlighted.

CONCLUSIONS

Participating in dual dispatch in case of suspected OHCA was described as a complex technical and emotional process by first responders. Providing case discussions and opportunities to give, and receive feedback about the case is a main task for the leadership in the organisations to diminish stress among personnel and to improve future OHCA missions.

Trends in survival from out-of-hospital cardiac arrests defibrillated by paramedics, first responders and bystanders

BACKGROUND

Although survival from out-of-hospital cardiac arrest (OHCA) is increasing, little is known about the long-term trends in survival for patients defibrillated by first responders and bystanders.

METHODS

Between 2000 and 2017, we included adult non-traumatic OHCA with an initial shockable rhythm from the Victorian Ambulance Cardiac Arrest Registry. Adjusted logistic regression analyses were used to assess trends in survival to hospital discharge according to whether the patient was initially shocked by paramedics, first responders or bystanders.

RESULTS

Of the 10,451 initial shockable arrests, 796 (7.6%) and 526 (5.0%) were initially shocked by first responders and bystanders, respectively. Between 2000-02 and 2015-17, the proportion of cases initially shocked by first responders and bystanders increased from 3.8% to 8.2% and from 2.0% to 11.2%, respectively. Over the same period, survival to hospital discharge increased from 11.6% to 28.8% for cases initially shocked by paramedics, from 10.5% to 37.8% for cases initially shocked by first responders, and from 6.7% to 55.5% for cases initially shocked by bystanders (p trend <0.001 for all). In the adjusted analyses, patients initially shocked by first responders (AOR 1.40, 95% CI: 1.18, 1.67; p < 0.001) and bystanders (AOR 2.11, 95% CI: 1.72, 2.59; p < 0.001) were more likely to survive to hospital discharge than those initially shocked by paramedics. The odds of survival increased year-on-year by 8.1% for patients shocked by paramedics (p < 0.001), 6.1% for patients shocked by first responders (p = 0.004), and 11.8% for patients shocked by bystanders (p < 0.001).

CONCLUSION

OHCA patients initially defibrillated by bystanders yielded the largest improvements in survival over time.

Public-access automated external defibrillator pad application and favorable neurological outcome after out-of-hospital cardiac arrest in public locations: A prospective population-based propensity score-matched study

BACKGROUND

Randomized controlled trials or observational studies showed that the use of public-access automated external defibrillator (AED) was effective for patients with out-of-hospital cardiac arrest (OHCA). However, it is unclear whether public-access AED use is effective for all patients with OHCA irrespective of first documented rhythm. We aimed to evaluate the effect of public-access AED use for OHCA patients considering first documented rhythm (shockable or non-shockable) in public locations.

METHODS

From the Utstein-style registry in Osaka City, Japan, we obtained information on adult patients with OHCA of medical origin in public locations before emergency-medical-service personnel arrival between 2011 and 2015. Primary outcome was 1-month survival with favorable neurological outcome. Multivariable logistic regression analysis was performed to assess the association between the public-access AED pad application and favorable neurological outcome after OHCA by using one-to-one propensity score matching analysis.

RESULTS

Among 1743 eligible patients, a total of 336 (19.3%) patients received public-access AED pad application. The proportion of patients who survived 1-month with favorable neurological outcome was significantly higher in the pad application group than in the non-pad application group (29.8% vs. 9.7%; adjusted odds ratio [AOR], 2.85; 95% confidence interval [CI], 1.73-4.68, AOR after propensity score matching, 2.46; 95% CI, 1.29-4.68). In a subgroup analysis, the AORs of patients with shockable or non-shockable rhythms were 3.36 (95% CI, 1.78-6.35) and 2.38 (95% CI, 0.89-6.34), respectively.

CONCLUSIONS

Public-access AED pad application was associated with better outcome among patients with OHCA of medical origin in public locations irrespective of first documented rhythm.

Public access of automated external defibrillators in a metropolitan city of China

BACKGROUND

Public access of automated external defibrillator (AED) is an important public health strategy for improving survival of cardiac arrest. Major metropolitan cities in China are increasingly investing and implementing public access defibrillator programs, but the effectiveness of these programs remains unclear. This study aims to evaluate the public accessibility of AED in Shanghai, a major metropolitan city in China.

METHODS

From July 1 to September 30, 2018, all AED locations indicated by AED Access Map Apps were visited and investigated in three most densely distributing areas of AED (Huangpu District, Xuhui District, and Central Area of the Pudong New District) in Shanghai. Two AED Access Map APPs were used to identify the location of AEDs. Characteristics of and the barriers to access, the AED sites were recorded. Awareness and skills of first aid and AED among on-site staff of the AED installation sites were evaluated.

RESULTS

A total of 283 sites were marked on two AED Apps. One hundred and seventy (60%) locations were accessible, and 142 (50%) were actually with AEDs installed. Among those AED installed sites, 112 (79%) were completely identifiable to the information on the maps, 20 (14%) were inconsistent and 10 (7%) were inaccurate on the maps. Ninety-four (66%) AEDs had visible signs and information around the location, 7 (5%) AEDs had signs outside of the location, and 107 (75%) sites had educational instructions. In addition, 230 individuals who were around the AED site were interviewed. Among them, 79 (34%) had good knowledge of AED. After shown the picture of AED, 112 (49%) knew whether there was AED in the site, and 108 (47%) knew the AED's location. Eighty-seven (38%) staff have received first aid training, and among them 26 (30%) reported that they had skills in operating the AED.

CONCLUSIONS

Public placement and accessibility of AEDs, related public signs and information on AED, and staff's awareness about AED were not optimal in Shanghai. Continuing efforts should be made to improve public accessibility and public awareness, knowledge, and user skills of AED.

Location of arrest and survival from out-of-hospital cardiac arrest among children in the public-access defibrillation era in Japan

BACKGROUND

Our objective was to assess the characteristics such as public-access defibrillation (PAD) by laypersons and the outcomes after pediatric out-of-hospital cardiac arrest by location in the PAD era.

METHODS

From a nationwide, prospective, population-based registry of out-of-hospital cardiac arrest patients in Japan, we enrolled consecutive pediatric patients aged ≤17 years before emergency medical service (EMS) arrival between 2013 and 2015. The primary outcome measure was 1-month survival, with favorable neurologic outcome defined as cerebral performance category 1 or 2. Factors associated with favorable neurologic outcome were assessed using multivariable logistic regression analysis.

RESULTS

Among 3991 eligible pediatric out-of-hospital cardiac arrests, the proportion of PAD was 0.2% (5/2888) at residence, 1.6% (2/125) in public areas, 0.9% (3/321) on streets/highways, 21.6% (11/51) at recreation/sports event areas, 46.1% (82/178) at education institutions, and 1.2% (5/428) in others. In the multivariable analysis, arrest witnessed by family members (adjusted odds ratio [AOR], 5.25; 95% confidence interval [CI], 3.22-8.58) and nonfamily members (AOR, 2.45; 95% CI, 1.26-4.77), first documented ventricular fibrillation (AOR, 12.29; 95% CI, 7.08-21.35), PAD (AOR, 2.63; 95% CI, 1.23-5.62), and earlier EMS response time (AOR for 1-min increment, 0.88; 95% CI, 0.81-0.94) were associated with improving outcome. As for locations, recreation/sports event areas (AOR, 3.43; 95% CI, 1.17-10.07) and education institutions (AOR, 3.03; 95% CI, 1.39-6.63) were also associated with favorable neurologic outcome.

CONCLUSIONS

In Japan, where public-access automated external defibrillators are well disseminated, characteristics such as PAD and outcomes for pediatric out-of-hospital cardiac arrest before EMS arrival differed substantially by location.

Accuracy of instructional diagrams for automated external defibrillator pad positioning

INTRODUCTION

Correct defibrillation pad positioning optimises the chances of successful defibrillation. AEDs have pictoral representation to guide untrained bystanders in correct pad positioning. There is a wide variation in this pictoral guidance and evidence suggests that correct anatomical pad placement is poor. We reviewed all currently available diagrams and assessed the resultant pad placement achieved by untrained bystanders following these instructions.

METHODS

Twenty untrained bystanders were presented with a total of 27 different pad placement diagrams (including one designed by the researchers) in a random sequence and were asked to apply them to the chest of an adult manikin. The lateral/medial and cranial/caudal position in relation to the optimal position recommended by the European Resuscitation Council guidelines was then measured for each pair of pads.

RESULTS

Overall, the sternal pad was placed an average of 6.0 mm cranial to, and 3.2 mm medial to, the optimal position. The apical pad was placed an average of 78.2 mm caudal to, and 59.3 mm medial to, the optimal position. The pad position diagram we designed and assessed out performed existing diagrams.

CONCLUSION

All current defibrillation pad diagrams fail to achieve accurate defibrillation pad placement. A clearer, more effective diagram, such as the one we designed, is urgently needed to ensure bystander defibrillation is effective as possible.

Basic life support by citizens in Kawasaki City, Japan - a descriptive epidemiological study of out-of-hospital cardiac arrest patients

AIM

To better understand the current status and barriers to making basic life support a common practice among the citizens of Kawasaki City, Japan.

METHOD

We extracted data according to the Utstein-style guidelines specifically regarding out-of-hospital cardiac arrests (OHCAs) of cardiac etiology. The items were as follows: (i) OHCA witnessed by a citizen, (ii) the victim received bystander cardiopulmonary resuscitation (CPR), (iii) an automatic external defibrillator was used by the witness. We compared the rate of each item and the 1-month survival rates with the national average in Japan. We further divided Kawasaki City into three areas and compared each item. We also examined the rate of bystander CPR in each time period and location. Statistical analysis was carried out using the χ²-test and Fisher's test.

RESULTS

The 1-month survival rates did not differ significantly from the national average for cases meeting conditions (i)-(iii): (i) 14.0% versus 13.3%, (ii) 19.1% versus 16.4%, (iii) 71.4% versus 53.3%, respectively. However, the rate of condition (i) was significantly lower (47.5% versus 55. 8%, P = 0.01). The rate of condition (ii) was higher in the northern area of Kawasaki City, as well as in a location other than the home in the daytime. The rate of condition (ii) was low in the home.

CONCLUSIONS

Although the 1-month survival rates of OHCAs witnessed by citizens in Kawasaki City did not differ significantly from the national average, the low rate of bystander CPR was notable, especially in the southern and middle areas of the city and when the location was in the home, which implies that basic life support knowledge should be spread to these areas.

Pediatric emergency medical services in privately insured patients: A 10-year national claims analysis

OBJECTIVE

To characterize pediatric Emergency Medicine Service (EMS) transports to the Emergency Department (ED) using a national claims database.

METHODS

We included children, 18 years and younger, transported by EMS to an ED, from 2007 to 2016 in the OptumLabs Data Warehouse. ICD-9 and ICD-10 diagnosis codes were used to categorize disease system involvement. Interventions performed were extracted using procedure codes. ED visit severity was measured by the Minnesota Algorithm.

RESULTS

Over a 10-year period, 239,243 children were transported. Trauma was the most frequent diagnosis category for transport for children ≥5 years of age, 35.1% (age 6-13) and 32.7% (age 14-18). The most common diagnosis category in children <6 years of age was neurologic (29.3%), followed by respiratory (23.1%). Over 10 years, transports for mental disorders represented 15.3% in children age 14 to 18, and had the greatest absolute increase (rate difference + 10.4 per 10,000) across all diagnoses categories. Neurologic transports also significantly increased in children age 14 to 18 (rate difference + 6.9 per 10,000). Trauma rates decreased across all age groups and had its greatest reduction among children age 14 to 18 (rate difference - 6.8 per 10,000). Across all age groups, an intervention was performed in 15.6%. Most children (83.3%) were deemed to have ED care needed type of visit, and 15.8% of the transports resulted in a hospital admission.

CONCLUSION

Trauma is the most frequent diagnosis for transport in children older than 5 years of age. Mental health and neurologic transports have markedly increased, while trauma transports have decreased. Most children arriving by ambulance were classified as requiring ED level of care. These changes might have significant implication for EMS personnel and policy makers.

Changes in automated external defibrillator use and survival after out-of-hospital cardiac arrest in the Nijmegen area

Purpose

Out-of-hospital cardiac arrests (OHCAs) are a major healthcare problem. Over the years, several initiatives have contributed to more lay volunteers providing cardiopulmonary resuscitation (CPR) and increased use of automated external defibrillators (AEDs) in the Netherlands. As part of a quality and outcomes program, we registered bystander CPR, AED use and outcome in the Nijmegen area.

Methods

Prospective resuscitation registry with a study cohort of non-traumatic OHCA cases from 2013–2016 and historical controls from 2008–2011. In line with previous reports, we studied patients transported to the hospital (Radboudumc, Nijmegen, the Netherlands) and excluded arrests witnessed by the emergency medical service (EMS). Primary outcomes were return of spontaneous circulation (ROSC) and survival to discharge.

Results

In the study cohort (n = 349) the AED was attached more often than in the historical cohort (n = 180): 46% vs. 23% and the proportion of bystander CPR was higher: 78% vs. 63% (both p < 0.001). A higher proportion of patients received an AED shock (39% vs. 15%, p < 0.001) and the number of required shocks by the EMS was lower (2 vs. 4, p = 0.004). Survival to discharge was higher (47% vs. 33%, p = 0.002) without differences in ROSC. The survival benefit was restricted to patients with a shockable initial rhythm. In both cohorts, bystander CPR and AED use were independently associated with survival.

Conclusion

In patients admitted after OHCA, survival to discharge has markedly improved to 40–50%, comparable with other Dutch registries. As increased bystander CPR and the doubled use of AEDs seem to have contributed, all civilian-based resuscitation initiatives should be encouraged.

Survival After Exercise-Related Sudden Cardiac Arrest in Young Athletes: Can We Do Better?

BACKGROUND:

Sudden cardiac arrest (SCA) is the leading cause of death in young athletes during sports.

HYPOTHESIS:

Survival after SCA in young athletes is variable.

STUDY DESIGN:

Prospective, active surveillance study.

LEVEL OF EVIDENCE:

Level 3.

METHODS:

From July 1, 2014, to June 30, 2016, exercise-related SCA in competitive young athletes was identified through a systematic search of traditional and social media sources, direct reporting to the National Center for Catastrophic Sports Injury Research, searching of the National Collegiate Athletic Association Resolutions List, regular communication with national and state high school athletic associations, and review of cases in the Parent Heart Watch database.

RESULTS:

A total of 132 cases were identified during the 2-year study period (mean patient age, 16 years; age range, 11-27 years; 84% male; 51% white non-Hispanic/Latino, 30% black/African American, and 11% white Hispanic/Latino). High school athletes accounted for 78 (59%) cases, with 28 (21%) in middle school and 15 (11%) in college athletes. Overall survival was 48% (95% CI, 40%-57%; 64 survivors, 68 deaths). Survival was similar in male versus female athletes but higher in white non-Hispanic/Latino (40/67; 60%) versus black/African American (13/39; 33%) athletes (difference, 27%; 95% CI, 7%-45%; P = 0.008) and white non-Hispanic/Latino versus all minority (18/59; 31%) athletes (difference, 29%; 95% CI, 13%-46%; P = 0.001). Basketball accounted for 30% of cases, followed by football (25%), track/cross-country (12%), and soccer (11%). The majority (93%) of cases were witnessed. If a certified athletic trainer was on-site and involved in the resuscitation, 83% of athletes survived. If an on-site automated external defibrillator was used in the resuscitation, 89% of athletes survived.

CONCLUSION:

Exercise-related SCA in young, competitive athletes is typically witnessed, providing an opportunity for rapid resuscitation. Additional research is needed to identify factors that affect survival in different athlete populations.

CLINICAL RELEVANCE:

Public access defibrillator programs should be universal in schools and youth sporting venues and have the potential to increase survival after SCA in young athletes.

Epidemiology, Outcomes and Coronary Angiography Findings of Patients Following Out-of-Hospital Cardiac Arrest: A single-centre experience from Oman

Objectives

Out-of-hospital cardiac arrests (OHCAs) are a leading cause of death worldwide. However, data regarding the management and outcomes of affected patients are lacking in the Middle East. The current study aimed to present the angiographic findings and outcomes of patients presenting with OHCA in Muscat, Oman.

Methods

This retrospective study took place between January 2012 and December 2016 at the Sultan Qaboos University Hospital (SQUH), Muscat, Oman. All adult patients who presented following an OHCA to the Emergency Department of SQUH during the study period were included. Demographic and clinical data were collected from electronic medical records.

Results

A total of 216 patients were included in the study. The majority (63.9%) presented after having collapsed, while 22.3% presented with chest pains. Asystole was the most frequent initial cardiac rhythm (62.5%), with only 10% having ventricular tachycardia/fibrillation. Very few patients (1.4%) had received cardiopulmonary resuscitation (CPR) prior to presentation. In total, 85 patients (39.4%) returned to spontaneous circulation (RSC); of these, post-RSC electrocardiography revealed an ST-segment elevation in 41.2% and normal findings in 23.5%. There were 63 patients who underwent coronary angiography, with 28 requiring stenting. Overall, 13% of patients survived and were discharged, although three survivors suffered permanent hypoxic brain damage.

Conclusion

The overall survival rate of patients who had experienced an OHCA was low. Education programmes should focus on the benefits of immediate CPR for individuals experiencing an OHCA, with more opportunities for CPR training to be made available to the general public in Oman.

Impact of Different Serum Potassium Levels on Postresuscitation Heart Function and Hemodynamics in Patients with Nontraumatic Out-of-Hospital Cardiac Arrest

Background

Sustained return of spontaneous circulation (ROSC) can be initially established in patients with out-of-hospital cardiac arrest (OHCA); however, the early postresuscitation hemodynamics can still be impaired by high levels of serum potassium (hyperkalemia). The impact of different potassium levels on early postresuscitation heart function has remained unclear. We aim to analyze the relationship between different levels of serum potassium and postresuscitation heart function during the early postresuscitation period (the first hour after achieving sustained ROSC).

Methods

Information on 479 nontraumatic OHCA patients with sustained ROSC was retrospectively obtained. Measures of early postresuscitation heart function (rate, blood pressure, and rhythm), hemodynamics (urine output and blood pH), and the duration of survival were analyzed in the case of different serum potassium levels (low: <3.5; normal: 3.5–5; high: >5 mmol/L).

Results

Most patients (59.9%, n = 287) had previously presented with high levels of potassium. Bradycardia, nonsinus rhythm, urine output <1 ml/kg/hr, and acidosis (pH < 7.35) were more common in patients with high levels of potassium (all p < 0.05). Compared with hyperkalemia, a normal potassium level was more likely to be associated with a normal heart rate (OR: 2.97, 95% CI: 1.74–5.08) and sinus rhythm (OR: 2.28, 95% CI: 1.45–3.58). A low level of potassium was more likely to be associated with tachycardia (OR: 3.54, 95% CI: 1.32–9.51), urine output >1 ml/kg/hr (OR: 5.35, 95% CI: 2.58–11.10), and nonacidosis (blood pH >7.35, OR: 7.74, 95% CI: 3.78–15.58). The duration of survival was shorter in patients with hyperkalemia than that in patients whose potassium levels were low or normal (p < 0.05).

Conclusion

Early postresuscitation heart function and hemodynamics were associated with the serum potassium level. A high potassium level was more likely to be associated with bradycardia, nonsinus rhythm, urine output <1 ml/kg/hr, and acidosis. More importantly, a high potassium level decreased the duration of survival.

Simulation of the Effects of Co-Locating Naloxone with Automated External Defibrillators

INTRODUCTION

Opioid-related overdoses have been steadily increasing over the past decade in the United States. Naloxone is used by first responders to revive overdose victims, but results may be improved by increasing access to and usage of naloxone by bystanders. Automated External Defibrillators (AEDs) are pervasive, recognizable, and publicly accessible. Co-locating naloxone kits with AEDs could increase public naloxone access and usage. However, the impact of co-locating naloxone kits with AEDs is not known.

OBJECTIVES

We sought to evaluate the impact of co-locating naloxone kits with AEDs in a simulation study centered on Allegheny County, Pennsylvania.

METHODS

Naloxone administration frequency (N = 3,650) at the zip-code level from March 2016 to March 2017 was provided by the Allegheny County Health Department. AED point locations (N = 1,653) were obtained from the University of Pittsburgh's Resuscitation Logistics and Informatics Venture. Zip-code level geospatial analyses were conducted using QGIS and STATA to determine the correlation between AED count and naloxone administrations. AED naloxone kit (N-AED) coverage, based on a maximum "walking-distance" radius of 200 m, was estimated at a zip-code level using the QGIS buffer tool and a custom MATLAB script. Potential impact of N-AEDs was estimated assuming uniform spatial distribution of naloxone administrations.

RESULTS

The median (IQR) AED coverage based on a 200 m access radius per zip code was 4% (0-7). The median (IQR) number of naloxone administrations per zip code was 27(7-55). A total of 82 zip codes had data for both AED locations and naloxone administrations. The correlation between number of AEDs and naloxone administrations per zip code was 0.20. Overall, 16% of naloxone administrations were estimated to be covered by an N-AED.

CONCLUSION

Using these limited methods, co-locating naloxone with AEDs is not likely to have a standalone impact on preventing overdose fatalities.

Impact of Bystander Automated External Defibrillator Use on Survival and Functional Outcomes in Shockable Observed Public Cardiac Arrests

BACKGROUND

Survival following out-of-hospital cardiac arrest (OHCA) with shockable rhythms can be improved with early defibrillation. Although shockable OHCA accounts for only ≈25% of overall arrests, ≈60% of public OHCAs are shockable, offering the possibility of restoring thousands of individuals to full recovery with early defibrillation by bystanders. We sought to determine the association of bystander automated external defibrillator use with survival and functional outcomes in shockable observed public OHCA.

METHODS

From 2011 to 2015, the Resuscitation Outcomes Consortium prospectively collected detailed information on all cardiac arrests at 9 regional centers. The exposures were shock administration by a bystander-applied automated external defibrillator in comparison with initial defibrillation by emergency medical services. The primary outcome measure was discharge with normal or near-normal (favorable) functional status defined as a modified Rankin Score ≤2. Survival to hospital discharge was the secondary outcome measure.

RESULTS

Among 49 555 OHCAs, 4115 (8.3%) observed public OHCAs were analyzed, of which 2500 (60.8%) were shockable. A bystander shock was applied in 18.8% of the shockable arrests. Patients shocked by a bystander were significantly more likely to survive to discharge (66.5% versus 43.0%) and be discharged with favorable functional outcome (57.1% versus 32.7%) than patients initially shocked by emergency medical services. After adjusting for known predictors of outcome, the odds ratio associated with a bystander shock was 2.62 (95% confidence interval, 2.07-3.31) for survival to hospital discharge and 2.73 (95% confidence interval, 2.17-3.44) for discharge with favorable functional outcome. The benefit of bystander shock increased progressively as emergency medical services response time became longer.

CONCLUSIONS

Bystander automated external defibrillator use before emergency medical services arrival in shockable observed public OHCA was associated with better survival and functional outcomes. Continued emphasis on public automated external defibrillator utilization programs may further improve outcomes of OHCA.

Sudden cardiac arrest on the field of play: turning tragedy into a survivable event

Sudden cardiac arrest remains the leading cause of death in exercising athletes, and recent studies have shown that it occurs more frequently than historical estimates. While out-of-hospital cardiac arrest often proves fatal, advance preparation can improve outcomes and the chance of survival. First responders to a collapsed athlete on the field of play may include team medical personnel, coaches, other athletes, officials, venue staff, emergency medical services personnel, or lay bystanders. Prompt and accurate recognition of sudden cardiac arrest, a comprehensive and rehearsed emergency action plan, early cardiopulmonary resuscitation, and immediate access to and use of an automated external defibrillator are each pivotal links in the chain of survival. This review summarises the components of an effective emergency action plan, highlights the critical role of automated external defibrillators, and reviews the diagnosis and management of sudden cardiac arrest on the field of play.

Improving Community Survival Rates from Out-of-Hospital Cardiac Arrest

Out of hospital cardiac arrest affects 350,000 Americans yearly and is associated with a high mortality rate. Improving survival rates in this population rests on the prompt and effective implementation of four key principles. These include 1) early recognition of cardiac arrest 2) early use of chest compressions 3) early defibrillation, which in turn emphasizes the importance of public access defibrillation programs and potential for drone technology to allow for early defibrillation in private or rural settings 4) early and aggressive post-arrest care including the consideration of therapeutic hypothermia, early coronary angiography +/- percutaneous coronary intervention and a hyper-invasive approach to out-of-hospital refractory cardiac arrest.

Bystander automated external defibrillator use and clinical outcomes after out-of-hospital cardiac arrest: A systematic review and meta-analysis

AIM

To systematically review studies comparing bystander automated external defibrillator (AED) use to no AED use in regard to clinical outcomes in out-of-hospital cardiac arrest (OHCA), and to provide a descriptive summary of studies on the cost-effectiveness of bystander AED use.

METHODS

We searched Medline, Embase, the Web of Science, and the Cochrane Library for randomized trials and observational studies published before June 1, 2017. Meta-analyses were performed for patients with all rhythms, shockable rhythms, and non-shockable rhythms.

RESULTS

Forty-four observational studies, 3 randomized trials, and 13 cost-effectiveness studies were included. Meta-analysis of 6 observational studies without critical risk of bias showed that bystander AED use was associated with survival to hospital discharge (all rhythms OR: 1.73 [95%CI: 1.36, 2.18], shockable rhythms OR: 1.66 [95%CI: 1.54, 1.79]) and favorable neurological outcome (all rhythms OR: 2.12 [95%CI: 1.36, 3.29], shockable rhythms OR: 2.37 [95%CI: 1.58, 3.57]). There was no association between bystander AED use and neurological outcome for non-shockable rhythms (OR: 0.76 [95%CI: 0.10, 5.87]). The Public-Access Defibrillation trial found higher survival rates when volunteers were equipped with AEDs. The other trials found no survival difference, although their study settings differed. The quality of evidence was low for randomized trials and very low for observational studies. AEDs were cost-effective in settings with high cardiac arrest incidence, with most studies reporting ratios < $100,000 per quality-adjusted life years.

CONCLUSIONS

The evidence supports the association between bystander AED use and improved clinical outcomes, although the quality of evidence was low to very low.