Use of the automatic external defibrillator in the management of out-of-hospital cardiac arrest

Automated external defibrillators and the link to first responder systems

PURPOSE OF REVIEW

Automated external defibrillators are a very effective treatment to convert ventricular fibrillation (VF) in out-of-hospital cardiac arrest. The purpose of this paper is to review recent publications related to automated external defibrillators (AEDs).

RECENT FINDINGS

Much of the recent research focus on ways to utilize publicly available AEDs included in different national/regional registers. More and more research present positive associations between engaging volunteers to increase the use of AEDs. There are only a few recent studies focusing on professional first responders such as fire fighters/police with mixed results. The use of unmanned aerial vehicles (drones) lacks clinical data and is therefore difficult to evaluate. On-site use of AED shows high survival rates but suffers from low incidence of out-of-hospital cardiac arrest (OHCA).

SUMMARY

The use of public AEDs in OHCA are still low. Systems focusing on engaging volunteers in the cardiac arrest response have shown to be associated with higher AED usage. Dispatching drones equipped with AEDs is promising, but research lacks clinical data. On-site defibrillation is associated with high survival rates but is not available for most cardiac arrests.

Optimizing Outcomes After Out-of-Hospital Cardiac Arrest With Innovative Approaches to Public-Access Defibrillation: A Scientific Statement From the International Liaison Committee on Resuscitation

Out-of-hospital cardiac arrest is a global public health issue experienced by ≈3.8 million people annually. Only 8% to 12% survive to hospital discharge. Early defibrillation of shockable rhythms is associated with improved survival, but ensuring timely access to defibrillators has been a significant challenge. To date, the development of public-access defibrillation programs, involving the deployment of automated external defibrillators into the public space, has been the main strategy to address this challenge. Public-access defibrillator programs have been associated with improved outcomes for out-of-hospital cardiac arrest; however, the devices are used in <3% of episodes of out-of-hospital cardiac arrest. This scientific statement was commissioned by the International Liaison Committee on Resuscitation with 3 objectives: (1) identify known barriers to public-access defibrillator use and early defibrillation, (2) discuss established and novel strategies to address those barriers, and (3) identify high-priority knowledge gaps for future research to address. The writing group undertook systematic searches of the literature to inform this statement. Innovative strategies were identified that relate to enhanced public outreach, behavior change approaches, optimization of static public-access defibrillator deployment and housing, evolved automated external defibrillator technology and functionality, improved integration of public-access defibrillation with existing emergency dispatch protocols, and exploration of novel automated external defibrillator delivery vectors. We provide evidence- and consensus-based policy suggestions to enhance public-access defibrillation and guidance for future research in this area.

Optimizing outcomes after out-of-hospital cardiac arrest with innovative approaches to public-access defibrillation: A scientific statement from the International Liaison Committee on Resuscitation

Out-of-hospital cardiac arrest is a global public health issue experienced by ≈3.8 million people annually. Only 8% to 12% survive to hospital discharge. Early defibrillation of shockable rhythms is associated with improved survival, but ensuring timely access to defibrillators has been a significant challenge. To date, the development of public-access defibrillation programs, involving the deployment of automated external defibrillators into the public space, has been the main strategy to address this challenge. Public-access defibrillator programs have been associated with improved outcomes for out-of-hospital cardiac arrest; however, the devices are used in <3% of episodes of out-of-hospital cardiac arrest. This scientific statement was commissioned by the International Liaison Committee on Resuscitation with 3 objectives: (1) identify known barriers to public-access defibrillator use and early defibrillation, (2) discuss established and novel strategies to address those barriers, and (3) identify high-priority knowledge gaps for future research to address. The writing group undertook systematic searches of the literature to inform this statement. Innovative strategies were identified that relate to enhanced public outreach, behavior change approaches, optimization of static public-access defibrillator deployment and housing, evolved automated external defibrillator technology and functionality, improved integration of public-access defibrillation with existing emergency dispatch protocols, and exploration of novel automated external defibrillator delivery vectors. We provide evidence- and consensus-based policy suggestions to enhance public-access defibrillation and guidance for future research in this area.

Analysis of the Way and Correctness of Using Automated External Defibrillators Placed in Public Space in Polish Cities-Continuation of Research

Immediate resuscitation is required for any sudden cardiac arrest. To improve the survival of the patient, a device to be operated by witnesses of the event-automated external defibrillator (AED)-has been produced. The aim of this study is to analyze the way and correctness of use of automated external defibrillators placed in public spaces in Polish cities. The data analyzed (using Excel 2019 and R 3.5.3 software) are 120 cases of use of automated external defibrillators, placed in public spaces in the territory of Poland in 2008-2018. The predominant location of AED use is in public transportation facilities, and the injured party is the traveler. AED use in non-hospital settings is more common in male victims aged 50-60 years. Owners of AEDs inadequately provide information about their use. The documentation that forms the basis of the emergency medical services intervention needs to be refined. There is no mention of resuscitation performed by a witness of an event or of the use of an AED. In addition, Poland lacks the legal basis for maintaining a register of automated external defibrillators. There is a need to develop appropriate documents to determine the process of reporting by the owners of the use of AEDs in out-of-hospital conditions (OHCA).

Use of Public Automated External Defibrillators in Out-of-Hospital Cardiac Arrest in Poland

Background and objectives: National medical records indicate that approximately 350,000–700,000 people die each year from sudden cardiac arrest. The guidelines of the European Resuscitation Council (ERC) and the International Liaison Committee on Resuscitation (ILCOR) indicate that in addition to resuscitation, it is important—in the case of so-called defibrillation rhythms—to perform defibrillation as quickly as possible. The aim of this study was to assess the use of public automated external defibrillators in out of hospital cardiac arrest in Poland between 2008 and 2018. Materials and Methods: One hundred and twenty cases of use of an automated external defibrillator placed in a public space between 2008 and 2018 were analyzed. The study material consisted of data on cases of use of an automated external defibrillator in adults (over 18 years of age). Only cases of automated external defibrillators (AED) use in a public place other than a medical facility were analysed, additionally excluding emergency services, i.e., the State Fire Service and the Volunteer Fire Service, which have an AED as part of their emergency equipment. The survey questionnaire was sent electronically to 1165 sites with AEDs and AED manufacturers. A total of 298 relevant feedback responses were received. Results: The analysis yielded data on 120 cases of AED use in a public place. Conclusions: Since 2016, there has been a noticeable increase in the frequency of use of AEDs located in public spaces. This is most likely related to the spread of public access to defibrillation and increased public awareness.

A walk through the progression of resuscitation medicine

Cardiac arrest (CA) is a sudden and devastating disease process resulting in more deaths in the United States than many cancers, metabolic diseases, and even car accidents. Despite such a heavy mortality burden, effective treatments have remained elusive. The past century has been productive in establishing the guidelines for resuscitation, known as cardiopulmonary resuscitation (CPR), as well as developing a scientific field whose aim is to elucidate the underlying mechanisms of CA and develop therapies to save lives. CPR has been successful in reinitiating the heart after arrest, enabling a survival rate of approximately 10% in out-of-hospital CA. Although current advanced resuscitation methods, including hypothermia and extracorporeal membrane oxygenation, have improved survival in some patients, they are unlikely to significantly improve the national survival rate any further without a paradigm shift. Such a change is possible with sustained efforts in the basic and clinical sciences of resuscitation and their implementation. This review seeks to discuss the current landscape in resuscitation medicine-how we got here and where we are going.

Renal denervation ameliorates the risk of ventricular fibrillation in overweight and heart failure

Aims

Both obesity and heart failure (HF) are associated with sudden cardiac death. The current study aimed to investigate the effects of overweight and HF on the substrate for ventricular fibrillation (VF), and whether renal denervation (RDN) can protect the heart from sympathetic activation and cardiac remodelling in HF rabbits fed with high-fat diet (HFD).

Methods and results

Twenty-four rabbits randomized into control group fed with regular diet (Control), HFD, HFD-HF, and HFD-HF-RDN groups. Rapid ventricular pacing of 400 b.p.m. for 4 weeks was applied in HFD-HF and HFD-HF-RDN. Surgical and chemical RDNs were approached through bilateral retroperitoneal flank incisions in HFD-HF-RDN. All rabbits received electrophysiological study and a VF inducibility test. The ventricular myocardium was harvested for trichrome stain. After 3 months, mean body weight was heavier in HFD, compared with control (3.5 ± 0.1 kg vs. 2.6 ± 0.1 kg, P &lt; 0.01). No differences in body weight among the three groups fed with HFD were observed. The ventricular refractory periods were longer in HFD-HF and HFD-HF-RDN than in control. An extension of ventricular fibrosis was observed in HFD and HFD-HF compared with control, and the degree of ventricular fibrosis was suppressed in HFD-HF-RDN compared with HFD-HF. The level of tyrosine hydroxylase staining was reduced in HFD-HF-RDN compared with HFD and HFD-HF. Importantly, VF inducibility was lower in HFD-RDN-HF (10 ± 4%), when compared with those in HFD-HF (58 ± 10%, P &lt; 0.01) and HFD (42 ± 5%, P &lt; 0.05), respectively.

Conclusion

Our results suggest that overweight and HF increase sympathetic activity, structural remodelling, and VF inducibility, but RDN prevents them.

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

BACKGROUND

Despite recent advances, the average survival after out-of-hospital cardiac arrest (OHCA) remains <10%. Early defibrillation by an automated external defibrillator is the most important intervention for patients with OHCA, showing survival proportions >50%. Accordingly, placement of automated external defibrillators in the community as part of a public access defibrillation program (PAD) is recommended by international guidelines. However, different strategies have been proposed on how exactly to increase and make use of publicly available automated external defibrillators. This systematic review aimed to evaluate the effect of PAD and the different PAD strategies on survival after OHCA.

METHODS

PubMed, Embase, and the Cochrane Library were systematically searched on August 31, 2015 for observational studies reporting survival to hospital discharge in OHCA patients where an automated external defibrillator had been used by nonemergency medical services. PAD was divided into 3 groups according to who applied the defibrillator: nondispatched lay first responders, professional first responders (firefighters/police) dispatched by the Emergency Medical Dispatch Center (EMDC), or lay first responders dispatched by the EMDC.

RESULTS

A total of 41 studies were included; 18 reported PAD by nondispatched lay first responders, 20 reported PAD by EMDC-dispatched professional first responders (firefighters/police), and 3 reported both. We identified no qualified studies reporting survival after PAD by EMDC-dispatched lay first responders. The overall survival to hospital discharge after OHCA treated with PAD showed a median survival of 40.0% (range, 9.1-83.3). Defibrillation by nondispatched lay first responders was associated with the highest survival with a median survival of 53.0% (range, 26.0-72.0), whereas defibrillation by EMDC-dispatched professional first responders (firefighters/police) was associated with a median survival of 28.6% (range, 9.0-76.0). A meta-analysis of the different survival outcomes could not be performed because of the large heterogeneity of the included studies.

CONCLUSIONS

This systematic review showed a median overall survival of 40% for patients with OHCA treated by PAD. Defibrillation by nondispatched lay first responders was found to correlate with the highest impact on survival in comparison with EMDC-dispatched professional first responders. PAD by EMDC-dispatched lay first responders could be a promising strategy, but evidence is lacking.

Prehospital Predictors of Initial Shockable Rhythm in Out-of-Hospital Cardiac Arrest: Findings From the Taichung Sudden Unexpected Death Registry (THUNDER)

OBJECTIVE

To identify the incidence and prehospital predictors of ventricular tachycardia/ventricular fibrillation (VT/VF) as the initial arrhythmia in patients with out-of-hospital cardiac arrest (OHCA) in central Taiwan.

PATIENTS AND METHODS

The Taichung Sudden Unexpected Death Registry program encompasses the Taichung metropolitan area in central Taiwan, with a population of 2.7 million and 17 destination hospitals for patients with OHCA. We performed a detailed analysis of demographic characteristics, circumstances of cardiac arrest, and emergency medical service records using the Utstein Style.

RESULTS

From May 1, 2013, through April 30, 2014, resuscitation was attempted in 2013 individuals with OHCA, of which 384 were excluded due to trauma and noncardiac etiologies. Of the 1629 patients with presumed cardiogenic OHCA, 7.9% (n=129) had initial shockable rhythm; this proportion increased to 18.8% (61 of 325) in the witnessed arrest subgroup. Male sex (odds ratio [OR], 2.45; 95% CI, 1.46-4.12; P<.001), age younger than 65 years (OR, 2.39, 95% CI, 1.58-3.62; P<.001), public location of arrest (OR, 4.61; 95% CI, 2.86-7.44; P<.001), and witnessed status (OR, 3.98; 95% CI, 2.62-6.05; P<.001) were independent predictors of VT/VF rhythm.

CONCLUSION

The proportion of patients with OHCA presenting with VT/VF was generally low in this East Asian population. Of the prehospital factors associated with VT/VF, public location of OHCA was the strongest predictor of VT/VF in this population, which may affect planning and deployment of emergency medical services in central Taiwan.

Barriers to EMS System Evaluation: Problems Associated with Field Data Collection

For more than two decades, emergency medical services (EMS) systems have proliferated primarily based upon governmental impetus and funding at the federal, state, and local levels. Although many of the foundations of patient care rendered in these systems have been based upon intuitive logic, the understanding of the impact on patient outcome is poor, at best. The reasons for the current status are varied, but five issues are preeminent:

1) The authority for the development of these medical systems has been based primarily in political and bureaucratic institutions which have little or no medical expertise;

2) Little attention has been paid to system evaluation, particularly in the area of cost-effectiveness;

3) Few academic medical institutions have become involved in EMS research;

4) Traditional approaches to medical research primarily are disease-specific and are not multidisciplinary. Thus these are not useful for evaluating and understanding the highly complex and uncontrolled environmental interactions that typify EMS systems; and

5) The process of efficiently and reliably collecting accurate data in the prehospital setting is extremely difficult.

Impact of European medicines agency recommendations for hypersensitivity reactions on intravenous iron prescription in haemodialysis centres of the Lombardy region

BACKGROUND

The European Medicines Agency (EMA) has recommended measures to minimize the risk of hypersensitivity reactions (HSRs) to intravenous iron (IVFe). We analysed the effects of these recommendations on IVFe clinical management among haemodialysis centres (HDCs) in Lombardy, Italy.

MATERIALS AND METHODS

A questionnaire was sent to all 117 HDCs to collect information on centre characteristics, e.g. HDC type [hospital centre (HC) vs. centre with limited assistance (CAL)], presence/absence of intensive care unit (ICU) and/or emergency trained staff, IVFe therapy regarding molecules, administration modalities, side effects, and percentage variations in iron prescription between 2014 and 2013 (outcome, Δ-IVFe%). A linear regression model was applied to evaluate the focus effect (β) of HDC type on the outcome, controlling for possible confounding effects of the other characteristics.

RESULTS

Response rate was 73.5 %. IVFe therapy was used in 69.1 % (HDC range 11-100) of patients. Following EMA recommendations, prescription was reduced by 12.6 %, with the largest reduction observed in CALs. No severe HSRs were reported. HCs had more frequently an ICU [97.2 vs. 20 %, odds ratio (OR) = 63.6 (95 % confidence interval 15.56; 537.47), p < 0.001], emergency trained staff [97.2 vs. 61.2 %, OR = 10.7 (2.68; 85.33), p < 0.001] and instrumental facilities (91.7 vs. 58 %, OR = 5.8 (2.03; 23.55), p < 0.001] than CALs. Linear regression demonstrated a significant raw effect of HDC type on Δ- IVFe% [β =  19.6 (9.82; 30.63), p < 0.001]. No association was found when HDC type was adjusted for ICU-presence [β = 6.7 (-2.32; 18.30), p = 0.199] or for all-confounding factors [β = 5.6 (-5.50; 17.08), p = 0.337].

CONCLUSIONS

This survey shows a disparity in IVFe therapy prescription following EMA recommendations, which is largely influenced by the presence/absence of ICUs in HD centres.

Basic life support knowledge of healthcare students and professionals in the Qassim University

OBJECTIVE

To evaluate the knowledge of basic life support (BLS) among students and health providers in Medicine, Pharmacy, Dentistry, and Allied Health Science Colleges at Qassim University.

METHODOLOGY

A cross sectional study was performed using an online BLS survey that was completed by 139 individuals.

RESULTS

Ninety-three responders were medical students, 7 were medical interns, 6 were dental students, 7 were pharmacy students, 11 were medical science students and 15 were clinical practitioners. No responder scored 100% on the BLS survey. Only two out of the 139 responders (1.4%) scored 90-99%. Both of these individuals were fifth year medical students. Six responders (4.3%) scored 80-89%. Of these, 5 were fifth year medical students, and one was fourth-year medical student. Eleven responders (7.9%) scored 70-79%. Of these, eight were fifth year medical students, two were medical interns and one was a pharmacist. Twenty-three responders (16.5%) scored 60-69%. Of these, 11 were fifth year medical students, 1 was a fourth-year medical student, 3 were medical interns, 2 were medical science students, 1 was a dentistry student, and 5 were pharmacists. Twenty-eight responders (20.1%) scored 50-59%. Of these, 11 were fifth year medical students, 3 were fourth-year medical students, 1 was a third-year medical student, 1 was a second-year medical student, 2 were first-year medical students, 1 was a pharmacy student, 3 were dental students, 1 was a allied health science student, 2 were doctors, and 3 were pharmacists. The remaining 69 responders (49.6%) scored less than 50%.

CONCLUSION

Knowledge of BLS among medicine, pharmacy, dentistry, and allied health science students and health providers at Qassim University is poor and needs to be improved. We suggest that inclusion of a BLS course in the undergraduate curriculum with regular reassessment would increase awareness and application of this valuable life-saving skill set.

Defibrillation in rural areas

AIM OF THE STUDY

Automated external defibrillation (AED) and public access defibrillation (PAD) have become cornerstones in the chain of survival in modern cardiopulmonary resuscitation. Most studies of AED and PAD have been performed in urban areas, and evidence is scarce for sparsely populated rural areas. The aim of this review was to review the literature and discuss treatment strategies for out-of-hospital cardiac arrest in rural areas.

METHODS

A Medline search was performed with the keywords automated external defibrillation (617 hits), public access defibrillation (256), and automated external defibrillator public (542). Of these 1415 abstracts and additional articles found by manually searching references, 92 articles were included in this nonsystematic review.

RESULTS

Early defibrillation is crucial for survival with good neurological outcome after cardiac arrest. Rapid defibrillation can be a challenge in sparsely populated and remote areas, where the incidence of cardiac arrest is low and rescuer response times can be long. The few studies performed in rural areas showed that the introduction of AED programs based on a 2-tier emergency medical system, consisting of Basic Life Support and Advanced Life Support teams, resulted in a decrease in collapse-to-defibrillation times and better survival of patients with out-of-hospital cardiac arrest.

CONCLUSIONS

In rural areas, introducing AED programs and a 2-tier emergency medical system may increase survival of out-of-hospital cardiac arrest patients. More studies on AED and PAD in rural areas are required.

Optimal installation locations for automated external defibrillators in Taipei 7-Eleven stores: using GIS and a genetic algorithm with a new stirring operator

Immediate treatment with an automated external defibrillator (AED) increases out-of-hospital cardiac arrest (OHCA) patient survival potential. While considerable attention has been given to determining optimal public AED locations, spatial and temporal factors such as time of day and distance from emergency medical services (EMSs) are understudied. Here we describe a geocomputational genetic algorithm with a new stirring operator (GANSO) that considers spatial and temporal cardiac arrest occurrence factors when assessing the feasibility of using Taipei 7-Eleven stores as installation locations for AEDs. Our model is based on two AED conveyance modes, walking/running and driving, involving service distances of 100 and 300 meters, respectively. Our results suggest different AED allocation strategies involving convenience stores in urban settings. In commercial areas, such installations can compensate for temporal gaps in EMS locations when responding to nighttime OHCA incidents. In residential areas, store installations can compensate for long distances from fire stations, where AEDs are currently held in Taipei.

The implementation of a dual dispatch system in out-of-hospital cardiac arrest is associated with improved short and long term survival

AIMS

To determine the impact of a dual dispatch system, using fire fighters as first responders, in out-of-hospital cardiac arrest (OHCA) on short (30 days) and long term (three years) survival, and, to investigate the potential differences regarding in-hospital factors and interventions between the patient groups, such as the use of therapeutic hypothermia and cardiac catheterization.

METHODS AND RESULTS

OHCAs from 2004 (historical controls) and 2006-2009 (intervention period) were included. During the intervention period, fire fighters equipped with automated external defibrillators (AEDs) were dispatched in suspected OHCA. Logistic regression analyses of outcome data included: the intervention with dual dispatch, sex, age, location, aetiology, witnessed status, bystander-cardiopulmonary resuscitation, first rhythm and therapeutic hypothermia. In total, 2581 OHCAs were included (historical controls n=620, intervention period n=1961). Fire fighters initiated cardiopulmonary resuscitation and connected an AED before emergency medical services' arrival in 41% of the cases. The median time from dispatch to arrival of first responder or emergency medical services shortened from 7.7 in the control period to 6.7 min in the intervention period (p<0.001). The 30-day survival improved from 3.9% to 7.6% (p=0.001), adjusted odds ratio 2.8 (confidence interval 1.6-4.9). Survival to three years increased from 2.4% to 6.5% (p<0.001), adjusted odds ratio 3.8 (confidence interval 1.9-7.6). In the logistic regression analysis including in-hospital factors we found no outcome benefit of therapeutic hypothermia.

CONCLUSIONS

The implementation of a dual dispatch system using fire fighters in OHCA was associated with increased 30-day and three-year survival. No major differences in the in-hospital treatment were seen between the studied patient groups.

Police AED programs: a systematic review and meta-analysis

BACKGROUND

Approximately 359,400 out-of-hospital cardiac arrests occur in the United States every year, and around 60% of them are treated by emergency medical services (EMS) personnel. In order to alleviate the impact of this public health burden, some communities have trained police officers as first responders so that they can provide cardiopulmonary resuscitation and defibrillation to cardiac arrest patients. This paper is a review of the current literature on the impact of police automated external defibrillators (AEDs) programs in these communities.

METHODS AND RESULTS

A literature search of electronic journal databases was conducted to identify articles that evaluated police AED programs and quantified survival rates. The 10 articles that met the inclusion criteria were very heterogeneous in terms of study design, controlling for confounders, outcome definitions, and comparison groups. Two communities found a statistically significant difference in survival and 6 studies reported a statistically significant difference in time to defibrillation after the implementation of these programs. The weighted mean survival rate of the study groups was higher than that of the control groups (p<0.001), as was the weighted mean survival rate of the group first shocked by police compared to those first shocked by EMS (39.4% vs. 28.6%, p<0.001). The pooled relative risk of survival was 1.4 (95% CI: 1.3-1.6).

CONCLUSIONS

Though there are many challenges in initiating these programs, this literature review shows that time to defibrillation decreased and survival from out-of-hospital cardiac arrests increased with the implementation of police AED programs.

High school automated external defibrillator programs as markers of emergency preparedness for sudden cardiac arrest

CONTEXT

School-based automated external defibrillator (AED) programs have demonstrated a high survival rate for individuals suffering sudden cardiac arrest (SCA) in US high schools.

OBJECTIVE

To examine the relationship between high schools having an AED on campus and other measures of emergency preparedness for SCA.

DESIGN

Cross-sectional study.

SETTING

United States high schools, December 2006 to September 2009.

PATIENTS OR OTHER PARTICIPANTS

Principals, athletic directors, school nurses, and certified athletic trainers represented 3371 high schools.

MAIN OUTCOME MEASURE(S)

Comprehensive surveys on emergency planning for SCA submitted by high school representatives to the National Registry for AED Use in Sports from December 2006 to September 2009. Schools with and without AEDs were compared to assess other elements of emergency preparedness for SCA.

RESULTS

A total of 2784 schools (82.6%) reported having 1 or more AEDs on campus, with an average of 2.8 AEDs per school; 587 schools (17.4%) had no AEDs. Schools with an enrollment of more than 500 students were more likely to have an AED (relative risk [RR] = 1.12, 95% confidence interval [CI] = 1.08, 1.16, P < .01). Suburban schools were more likely to have an AED than were rural (RR = 1.08, 95% CI = 1.04, 1.11, P < .01), urban (RR = 1.13, 95% CI = 1.04, 1.16, P < .01), or inner-city schools (RR = 1.10, 95% CI = 1.04, 1.23, P < .01). Schools with 1 or more AEDs were more likely to ensure access to early defibrillation (RR = 3.45, 95% CI = 2.97, 3.99, P < .01), establish an emergency action plan for SCA (RR = 1.83, 95% CI = 1.67, 2.00, P < .01), review the emergency action plan at least annually (RR = 1.99, 95% CI = 1.58, 2.50, P < .01), consult emergency medical services to develop the emergency action plan (RR = 1.18, 95% CI = 1.05, 1.32, P < .01), and establish a communication system to activate emergency responders (RR = 1.06, 95% CI = 1.01, 1.08, P < .01).

CONCLUSIONS

High schools with AED programs were more likely to establish a comprehensive emergency response plan for SCA. Implementing school-based AED programs is a key step associated with emergency planning for young athletes with SCA.

In-Field Comparison between Fully Automatic and Semi-Automatic Defibrillators

The purpose of this clinical study was to compare the prehospital use of fully automatic defibrillators versus semi-automatic defibrillators.

Methods:

Fully and semi-automatic defibrillator use by EMTs in neighboring communities was compared.

Results:

Both programs had similar response times, age and gender distribution, proportion of witnessed arrests, and proportion of patients found initially with ventricular fibrillation (VF). The time-to-shock from proper lead placement was shorter when the fully automatic defibrillator was used (16.6 vs. 44.3 seconds; p<.001) and the survival to hospital discharge rate was greater (26% vs. 0%; p=.O4). The semi-automatic defibrillators were more sensitive in detecting VF than were the fully automatic devices.

Conclusions:

These data support the need for further comparison of the efficacy and effectiveness of semi- and fully automatic, external defibrillators.

A Prospective Evaluation of Prehospital Patient Assessment by Direct In-field Observation: Failure of ALS Personnel to Measure Vital Signs

We prospectively evaluated the frequency with which advanced life support (ALS) personnel fail to attempt to measure blood pressure (BP) and/or pulse (P) during prehospital patient assessment. A single in-field observer rode on ALS rescue vehicles from 20 Emergency Medical Services (EMS) agencies throughout Arizona during a one-year study (1/89–12/89). Data were collected from urban, suburban, and rural systems. Statistical evaluation was performed by Chi Square analysis with p <0.05 considered significant.

Among 227 patient encounters, BP and/or P measurements were omitted in 84 cases (37.0%). BP and/or P were omitted in 50.0% of children (age <18 years) compared to 26.5% of adults (p=0.023). Among patients who were transported to a hospital, 19.4% had BP omitted compared to 49.1% of those not transported (p=0.00003). Seven of 58 patients in whom TVs were attempted (12.1 %) had BP omitted compared to 54 of 169 patients without IV attempts (32.0%, p=0.0055). Blood Pressure was omitted in 21.9% of patients transported Code 3 and in 24.2% of patients with Glasgow Coma Scale ≤13. Omission of BP occurred more frequently in non-urban agencies (33.9%) than in urban ones (20.0%, p=0.027).

In a statewide evaluation of prehospital patient assessment, failure to measure vital signs (VS) occurred on a frequent basis. Our data indicate that a concerning lack of attention to the most basic details of patient assessment is common. It is possible that failure to measure VS might even happen more frequently during routine patient encounters without an observer present. Medical control physicians must emphasize to EMS personnel the paramount importance of careful assessment to ensure optimal patient care.

Analysis of Prehospital Scene Time and Survival from Out-of-Hospital, Non-Traumatic, Cardiac Arrest

The purpose of this study was to determine whether shorter prehospital scene time (ST) is associated with an increased survival rate in non-traumatic, out-of-hospital, cardiac arrest (CA) in a medium-sized, metropolitan EMS system. Information was retrieved for all adult victims (age ≥18 years) of CA treated and transported by a metropolitan fire department over a 16month period (6/87–9/88). Data were retrieved from the fire department's database, hospital records, and death certificates. Statistical analysis of continuous variables was performed using the two-tailed, Student's t-test and non-parametric evaluations were performed by square analysis with p<0.05 considered significant. Two hundred ninety-eight cases were recorded of which 293 patients (98.3%) had documented ST (study group). Seventy-nine patients (27.0%) had ST <12 minutes, while 214 (73.0%) had ST≥12 minutes. Patients with ST <12 minutes were more likely to have return of spontaneous circulation in the field (26.6% vs. 15.9%, p<0.05) and also were more likely to survive than were patients with ST ≥12 minutes (13.9% vs. 6.5%, p<0.05). Mean ST for survivors was significantly less than for non-survivors (12.8 vs. 15.3 min., p<0.05).

We conclude that, in our system, adult victims of CA with ST <12 minutes are more likely to survive than are patients with longer ST. In addition, the mean ST for survivors is shorter than for non-survivors. It remains unclear whether shorter ST actually has an impact on survival or is merely a reflection of a sub-group with rapid resuscitation and consequently a higher likelihood of survival. Future investigations are needed to determine whether shorter ST actually impacts the likelihood of survival from CA.

Implantable cardioverter-defibrillators and the young athlete: can the two coexist?

Since the incorporation of implantable cardioverter-defibrillators (ICDs) into the management of life threatening arrhythmias in the 1980s, tremendous advances in device and lead technology have allowed the implantation of ICD systems in younger and smaller patients. The majority of these young patients with ‘‘electrical’’ cardiac disease and a significant number of those with other indications for ICD placement have near normal to normal cardiac function, which has resulted in a large population of young ICD patients with minimal to no symptoms. This population has pushed the boundaries of published guidelines on activity restrictions for the disease state and the presence of an ICD, creating a dilemma for the patient, the family, and the health care team with regard to which activities should be permitted. Strong evidence suggests that vigorous activity increases the probability of life threatening arrhythmias in the at-risk population. In addition,repetitive training and high levels of exertion may decrease the durability of the ICD system, leading to inappropriate or ineffective device therapy. However, competitive sports promote regular physical activity, even at the novice level, and regular physical exercise confers numerous short- and long-term benefits. The clinician must always balance the potential risk in sports participation for the patient who has an ICD with the documented adverse effects of chronic physical inactivity. The decision to allow sports participation is multifactorial and therefore cannot be made purely on the basis of consensus statements or the patient’s desire to compete.

National athletic trainers' association position statement: preventing sudden death in sports

OBJECTIVE

To present recommendations for the prevention and screening, recognition, and treatment of the most common conditions resulting in sudden death in organized sports.

BACKGROUND

Cardiac conditions, head injuries, neck injuries, exertional heat stroke, exertional sickling, asthma, and other factors (eg, lightning, diabetes) are the most common causes of death in athletes.

RECOMMENDATIONS

These guidelines are intended to provide relevant information on preventing sudden death in sports and to give specific recommendations for certified athletic trainers and others participating in athletic health care.

Automated external defibrillators in health and fitness facilities

BACKGROUND

Exercise is encouraged to promote health, but it can be a trigger for sudden cardiac arrest (SCA) in individuals with underlying cardiovascular disease. In 2002, the American Heart Association and the American College of Sports Medicine issued recommendations for the presence of automated external defibrillators (AEDs) in health and fitness facilities.

OBJECTIVE

To assess emergency response planning for SCA and review the prevalence and past utilization of AEDs in health and fitness facilities in King County, WA.

METHODS

A cross-sectional survey was conducted in 2008 of health and fitness facilities (N = 136) in King County, WA, assessing the 2002 American Heart Association guidelines on AEDs and emergency response planning for SCA.

RESULTS

Sixty-three (46%) of 136 facilities completed the survey. Thirty-five percent of the total facilities had < 500 members, 21% had 500 to 1500 members, 16% had 1501 to 2500 members, and 29% had > 2500 members. Sixty-eight percent had an established emergency response plan for SCA. Only 40% of facilities had ≥ 1 AED on site (mean, 1.7; range, 0-6). Fitness centers with > 1500 members (71%) were more likely to have an AED on site compared with those with < 1500 members (14%) (P < 0.0001). Of the staff trained in cardiopulmonary resuscitation, 83% were fitness instructors, 73% were administrators, and 58% were front desk personnel. Four facilities reported an incident of SCA within the 12 months prior to completing the survey, which was a 6.4% incidence of SCA in responding facilities. All SCA cases occurred in facilities with > 1500 members. Only 2 of the 4 facilities with an SCA had an on-site AED. The individuals who had SCA were all men aged 50 to 65 years, with 2 men successfully resuscitated at the facility.

CONCLUSION

There is a substantial gap in guideline implementation between national recommendations and current emergency response planning for SCA in health and fitness facilities. Health and fitness facilities are strategic locations to place AEDs in an effort to improve outcomes from exercise-related SCA. Facilities with general memberships of > 1500 are encouraged to have on-site AEDs, given the high incidence of SCA.

Advances in cardiopulmonary resuscitation

This article focuses on important advances in the science of cardiopulmonary resuscitation in the last decade that have led to a significant improvement in understanding the complex physiology of cardiac arrest and critical interventions for the initial management of cardiac arrest and postresuscitation treatment. Special emphasis is given to the basic simple ways to improve circulation, vital organ perfusion pressures, and the grave prognosis of sudden cardiac death.

Automated external defibrillators and survival after in-hospital cardiac arrest

CONTEXT

Automated external defibrillators (AEDs) improve survival from out-of-hospital cardiac arrests, but data on their effectiveness in hospitalized patients are limited.

OBJECTIVE

To evaluate the association between AED use and survival for in-hospital cardiac arrest.

DESIGN, SETTING, AND PATIENTS

Cohort study of 11,695 hospitalized patients with cardiac arrests between January 1, 2000, and August 26, 2008, at 204 US hospitals following the introduction of AEDs on general hospital wards.

MAIN OUTCOME MEASURE

Survival to hospital discharge by AED use, using multivariable hierarchical regression analyses to adjust for patient factors and hospital site.

RESULTS

Of 11,695 patients, 9616 (82.2%) had nonshockable rhythms (asystole and pulseless electrical activity) and 2079 (17.8%) had shockable rhythms (ventricular fibrillation and pulseless ventricular tachycardia). AEDs were used in 4515 patients (38.6%). Overall, 2117 patients (18.1%) survived to hospital discharge. Within the entire study population, AED use was associated with a lower rate of survival after in-hospital cardiac arrest compared with no AED use (16.3% vs 19.3%; adjusted rate ratio [RR], 0.85; 95% confidence interval [CI], 0.78-0.92; P < .001). Among cardiac arrests due to nonshockable rhythms, AED use was associated with lower survival (10.4% vs 15.4%; adjusted RR, 0.74; 95% CI, 0.65-0.83; P < .001). In contrast, for cardiac arrests due to shockable rhythms, AED use was not associated with survival (38.4% vs 39.8%; adjusted RR, 1.00; 95% CI, 0.88-1.13; P = .99). These patterns were consistently observed in both monitored and nonmonitored hospital units where AEDs were used, after matching patients to the individual units in each hospital where the cardiac arrest occurred, and with a propensity score analysis.

CONCLUSION

Among hospitalized patients with cardiac arrest, use of AEDs was not associated with improved survival.

The effectiveness and cost effectiveness of public-access defibrillation

Many sudden cardiac deaths are due to ventricular fibrillation (VF). The use of defibrillators in hospitals or by outpatient emergency medical services (EMS) personnel can save many cardiac-arrest victims. Automated external defibrillators (AEDs) permit defibrillation by trained first responders and laypersons. AEDs are available at most public venues, and vast sums of money are spent installing and maintaining these devices. AEDs have been evaluated in a variety of public and private settings. AEDs accurately identify malignant ventricular tachyarrhythmias and frequently result in successful defibrillation. Prompt application of an AED shows a greater number of patients in VF compared with initial rhythms documented by later-arriving EMS personnel. Survival is greatest when the AED is placed within 3 to 5 minutes of a witnessed collapse. Community-based studies show increased cardiac-arrest survival when first responders are equipped with AEDs rather than waiting for paramedics to defibrillate. Wide dissemination of AEDs throughout a community increases survival from cardiac arrest when the AED is used; however, the AEDs are utilized in a very small percentage of all out-of-hospital cardiac arrests. AEDs save very few lives in residential units such as private homes or apartment complexes. AEDs are cost effective at sites where there is a high density of both potential victims and resuscitators. Placement at golf courses, health clubs, and similar venues is not cost effective; however, the visible devices are good for public awareness of the problem of sudden cardiac death and provide reassurance to patrons.

ECG spectral and morphological parameters reviewed and updated to detect adult and paediatric life-threatening arrhythmia

Since the International Liaison Committee on Resuscitation approved the use of automated external defibrillators (AEDs) in children, efforts have been made to adapt AED algorithms designed for adult patients to detect paediatric ventricular arrhythmias accurately. In this study, we assess the performance of two spectral (A(2) and VFleak) and two morphological parameters (TCI and CM) for the detection of lethal ventricular arrhythmias using an American Heart Association (AHA) compliant database that includes adult and paediatric arrhythmias. Our objective was to evaluate how those parameters can be optimally adjusted to discriminate shockable from nonshockable rhythms in adult and paediatric patients. A total of 1473 records were analysed: 751 from 387 paediatric patients (<or=16 years of age) and 722 records from 381 adult patients. The spectral parameters showed no significant differences (p > 0.01) between the adult and paediatric patients for the shockable records; the differences for nonshockable records however were significant. Still, these parameters maintained the discrimination power when paediatric rhythms were included. A single threshold could be adjusted to obtain sensitivities and specificities above the AHA goals for the complete database. The sensitivities for ventricular fibrillation (VF) and ventricular tachycardia (VT) were 91.1% and 96.6% for VFleak, and 90.3% and 99.3% for A(2). The specificities for normal sinus rhythm (NSR) and other nonshockable rhythms were 99.5% and 96.3% for VFleak, and 99.0% and 97.7% for A(2). On the other hand, the morphological parameters showed significant differences between the adult and paediatric patients, particularly for the nonshockable records, because of the faster heart rates of the paediatric rhythms. Their performance clearly degraded with paediatric rhythms. Using a single threshold, the sensitivities and specificities were below the AHA goals, particularly VT sensitivity (60.4% for TCI and 65.8% for CM) and the specificity for other nonshockable rhythms (51.7% for TCI and 34.5% for CM). The specificities, particularly for the adult case, improve when the thresholds are independently adjusted for each adult and paediatric database.

Treating critical supraventricular and ventricular arrhythmias

Atrial fibrillation (AF), atrial flutter, AV-nodal reentry tachycardia with rapid ventricular response, atrial ectopic tachycardia and preexcitation syndromes combined with AF or ventricular tachyarrhythmias (VTA) are typical arrhythmias in intensive care patients (pts). Most frequently, the diagnosis of the underlying arrhythmia is possible from the physical examination (PE), the response to maneuvers or drugs and the 12-lead surface electrocardiogram. In unstable hemodynamics, immediate DC-cardioversion is indicated. Conversion of AF to sinus rhythm (SR) is possible using antiarrhythmic drugs. Amiodarone has a conversion rate in AF of up to 80%. Ibutilide represents a class III antiarrhythmic agent that has been reported to have conversion rates of 50-70%. Acute therapy of atrial flutter (Aflut) in intensive care pts depends on the clinical presentation. Atrial flutter can most often be successfully cardioverted to SR with DC-energies <50 joules. Ibutilide trials showed efficacy rates of 38-76% for conversion of Aflut to SR compared to conversion rates of 5-13% when intravenous flecainide, propafenone or verapamil was administered. In addition, high dose (2 mg) of ibutilide was more effective than sotalol (1.5 mg/kg) in conversion of Aflut to SR (70 versus 19%). Drugs like procainamide, sotalol, amiodarone or magnesium were recommended for treatment of VTA in intensive care pts. However, only amiodarone is today the drug of choice in VTA pts and also highly effective even in pts with defibrillation-resistant out-of-hospital cardiac arrest (CA). There is a general agreement that bystander first aid, defibrillation and advanced life support is essential for neurologic outcome in pts after cardiac arrest due to VTA. Public access defibrillation in the hands of trained laypersons seems to be an ideal approach in the treatment of ventricular fibrillation (VF). The use of automatic external defibrillators (AEDs) by basic life support ambulance providers or first responder (FR) in early defibrillation programs has been associated with a significant increase in survival rates (SRs). However, use of AEDs at home cannot be recommended.

Evidence-based optimization of urban firefighter first response to emergency medical services 9-1-1 incidents

INTRODUCTION

Many emergency medical services (EMS) systems dispatch nonparamedic firefighter first responders (FFRs) to selected EMS 9-1-1 calls, intending to deliver time-sensitive interventions such as defibrillation, cardiopulmonary resuscitation (CPR), and bag-mask ventilation prior to arrival of paramedics. Deciding when to send FFRs is complicated because critical cases are rare, paramedics often arrive before FFRs, and lights-and-siren responses by emergency vehicles are associated with the risk of en-route traffic collisions.

OBJECTIVE

To describe a methodology allowing EMS systems to optimize their own FFR programs using local data, and reflecting local medical oversight policy and local risk-benefit opinion.

METHODS

We constructed a generalized input-output model that retrospectively reviews EMS dispatch and electronic prehospital clinical records to identify a subset of Medical Priority Dispatch System (MPDS) call categories ("determinants") that maximize the opportunities for FFR interventions while minimizing unwarranted responses. Input parameters include local FFR interventions, the local FFR "first-on-scene" rate, and the locally acceptable ratio of risk to benefit. The model uses a receiver-operating characteristic (ROC) curve to identify the optimal mix of response specificity and sensitivity achieved by sending FFRs to progressively more categories of EMS calls while remaining within a defined risk-benefit ratio. The model was applied to a 16-month retrospective sample of 220,358 incidents from a large urban EMS system to compare the model's recommendations with the system's current practices.

RESULTS

The model predicts that FFR lights-and-siren responses in the sample could be reduced by 83%, from 93,058 to 16,091 incidents, by confining FFR responses to 27 of 509 MPDS dispatch determinants, representing 7.3% of incidents but 58.9% of all predicted FFR interventions. Of the 93,058 incidents, another 58,275 incidents could be downgraded to safer nonemergency FFR responses and 18,692 responses could be eliminated entirely, improving the specificity of FFR response from 57.8% to 93.0%.

CONCLUSIONS

This model provides a robust generalized methodology allowing EMS systems to optimize FFR lights-and-siren responses to emergency medical calls. Further validation is warranted to assess the model's generality.

Survival increases with CPR by Emergency Medical Services before defibrillation of out-of-hospital ventricular fibrillation or ventricular tachycardia: observations from the Resuscitation Outcomes Consortium

BACKGROUND

Immediate defibrillation is the traditional approach to resuscitation of cardiac arrest due to ventricular fibrillation or tachycardia (VF/VT). Delaying defibrillation to provide chest compressions may improve survival. We examined the effect of the duration of Emergency Medical Services (EMS) cardiopulmonary resuscitation (CPR) prior to first defibrillation on survival in patients with out-of-hospital VF/VT.

MATERIALS AND METHODS

From a prospective multi-center observational registry of EMS-treated out-of-hospital cardiac arrest, we identified 1638 EMS-treated cardiac arrests with first recorded rhythm VF/VT or "shockable" and complete data for analysis. Survival to hospital discharge was determined as a function of EMS CPR duration prior to first shock.

RESULTS

Compared to the reference group of first EMS CPR duration < or =45 s, the odds of survival was greater among patients who received between 46 and 195 s of EMS CPR before first shock (46-75 s odds ratio [OR] 1.15, 95% confidence interval [CI] 0.71-1.87; 76-105 s, OR 1.37, 95% CI 0.80-2.35; 106-135 s, OR 1.53, 95% CI 0.96-2.45; 136-165 s, OR 1.24, 95% CI 0.71-2.15; 166-195 s, OR 1.47, 95% CI 0.85-2.52). The benefit of EMS CPR before defibrillation was reduced when the duration of CPR exceeded 195 s (196-225 s, OR 0.95, 95% CI 0.47-1.81; 226-255 s, OR 0.91, 95% CI 0.46-1.79; 256-285 s, OR 0.46, 95% CI 0.17-1.29; 286-315 s, OR 1.29, 95% CI 0.59-2.85). An optimal EMS CPR duration was not identified and no duration achieved statistical significance.

CONCLUSION

In this observational analysis of VF/VT arrest, between 46 and 195 s of EMS CPR prior to defibrillation was weakly associated with improved survival compared to < or =45 s. Randomized trials are needed to confirm the optimal duration of EMS CPR prior to defibrillation and to assess the impact of first CPR duration on all initial rhythms.