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.

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.

BACKGROUND: Prior studies have identified key predictors of out-of-hospital cardiac arrest (OHCA), but differences exist in the magnitude of these findings. In this meta-analysis, we evaluated the strength of associations between OHCA and key factors (event witnessed by a bystander or emergency medical services [EMS], provision of bystander cardiopulmonary resuscitation [CPR], initial cardiac rhythm, or the return of spontaneous circulation). We also examined trends in OHCA survival over time. METHODS AND RESULTS: An electronic search of PubMed, EMBASE, Web of Science, CINAHL, Cochrane DSR, DARE, ACP Journal Club, and CCTR was conducted (January 1, 1950 to August 21, 2008) for studies reporting OHCA of presumed cardiac etiology in adults. Data were extracted from 79 studies involving 142 740 patients. The pooled survival rate to hospital admission was 23.8% (95% CI, 21.1 to 26.6) and to hospital discharge was 7.6% (95% CI, 6.7 to 8.4). Stratified by baseline rates, survival to hospital discharge was more likely among those: witnessed by a bystander (6.4% to 13.5%), witnessed by EMS (4.9% to 18.2%), who received bystander CPR (3.9% to 16.1%), were found in ventricular fibrillation/ventricular tachycardia (14.8% to 23.0%), or achieved return of spontaneous circulation (15.5% to 33.6%). Although 53% (95% CI, 45.0% to 59.9%) of events were witnessed by a bystander, only 32% (95% CI, 26.7% to 37.8%) received bystander CPR. The number needed to treat to save 1 life ranged from 16 to 23 for EMS-witnessed arrests, 17 to 71 for bystander-witnessed, and 24 to 36 for those receiving bystander CPR, depending on baseline survival rates. The aggregate survival rate of OHCA (7.6%) has not significantly changed in almost 3 decades. CONCLUSIONS: Overall survival from OHCA has been stable for almost 30 years, as have the strong associations between key predictors and survival. Because most OHCA events are witnessed, efforts to improve survival should focus on prompt delivery of interventions of known effectiveness by those who witness the event.

BACKGROUND: Actual application of public-access automated external defibrillator (AED) pads to patients with an out-of-hospital cardiac arrest (OHCA) by the public has been poorly investigated. METHODS: AED applications, prehospital characteristics, and one-month outcomes of OHCAs occurring in Osaka Prefecture from 2011 to 2012 were obtained from the Utstein Osaka Project registry. Patients with a non-traumatic OHCA occurring before emergency medical service attendance were enrolled. The proportion of AED pads that were applied to the patients' chests by the public and one-month outcomes were analysed according to the location of OHCA. RESULTS: In total, public-access AED pads were applied to 3.5% of OHCA patients (351/9978) during the study period. In the multivariate analyses, OHCAs that occurred in public places and received bystander-initiated cardiopulmonary resuscitation were associated with significantly higher application of public-access AEDs. Among the patients for whom public-access AED pads were applied, 29.6% (104/351) received public-access defibrillation. One-month survival with a favourable neurological outcome was significantly higher among patients who had an AED applied compared to those who did not (19.4% vs. 3.0%; OR: 2.76 [95% CI: 1.92-3.97]). CONCLUSION: The application of public-access AEDs leads to favourable outcomes after an OHCA, but utilisation of available equipment remains insufficient, and varies considerably according to the location of the OHCA event. Alongside disseminating public-access AEDs, further strategic approaches for the deployment of AEDs at the scene, as well as basic life support training for the public are required to improve survival rates after OHCAs.

AIM: An increasing number of failing automated external defibrillators (AEDs) is reported: AEDs not giving a shock or other malfunction. We assessed to what extent AEDs are 'failing' and whether this had a device-related or operator-related cause. METHODS: We studied analysis periods from AEDs used between January 2012 and December 2014. For each analysis period we assessed the correctness of the (no)-shock advice (sensitivity/specificity) and reasons for an incorrect (no)-shock advice. If no shock was delivered after a shock advice, we assessed the reason for no-shock delivery. RESULTS: We analyzed 1114 AED recordings with 3310 analysis periods (1091 shock advices; 2219 no-shock advices). Sensitivity for coarse ventricular fibrillation was 99% and specificity for non-shockable rhythm detection 98%. The AED gave an incorrect shock advice in 4% (44/1091) of all shock advices, due to device-related (n=15) and operator-related errors (n=28) (one unknown). Of these 44 shock advices, only 2 shocks caused a rhythm change. One percent (26/2219) of all no-shock advices was incorrect due to device-related (n=20) and operator-related errors (n=6). In 5% (59/1091) of all shock advices, no shock was delivered: operator failed to deliver shock (n=33), AED was removed (n=17), operator pushed 'off' button (n=8) and other (n=1). Of the 1073 analysis periods with a shockable rhythm, 67 (6%) did not receive an AED shock. CONCLUSION: Errors associated with AED use are rare (4%) and when occurring are in 72% caused by the operator or circumstances of use. Fully automatic AEDs may prevent the majority of these errors.

BACKGROUND: In Copenhagen, a volunteer-based Automated External Defibrillator (AED) network provides a unique opportunity to assess AED use. We aimed to determine the proportion of Out-of-Hospital Cardiac Arrest (OHCA) where an AED was applied before arrival of the ambulance, and the proportion of OHCA-cases where an accessible AED was located within 100 m. In addition, we assessed 30-day survival. METHODS: Using data from the Mobile Emergency Care Unit and the Danish Cardiac Arrest Registry, we identified 521 patients with OHCA between October 1, 2011 and September 31, 2013 in Copenhagen, Denmark. RESULTS: An AED was applied in 20 cases (3.8%, 95% CI [2.4 to 5.9]). Irrespective of AED accessibility, an AED was located within 100 m of a cardiac arrest in 23.4% (n=102, 95% CI [19.5 to 27.7]) of all OHCAs. However, at the time of OHCA, an AED was located within 100 m and accessible in only 15.1% (n=66, 95% CI [11.9 to 18.9]) of all cases. The 30-day survival for OHCA with an initial shockable rhythm was 64% for patients where an AED was applied prior to ambulance arrival and 47% for patients where an AED was not applied. CONCLUSIONS: We found that 3.8% of all OHCAs had an AED applied prior to ambulance arrival, but 15.1% of all OHCAs occurred within 100 m of an accessible AED. This indicates the potential of utilising AED networks by improving strategies for AED accessibility and referring bystanders of OHCA to existing AEDs.

The International Liaison Committee on Resuscitation has initiated a near-continuous review of cardiopulmonary resuscitation science that replaces the previous 5-year cyclic batch-and-queue approach process. This is the first of an annual series of International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations summary articles that will include the cardiopulmonary resuscitation science reviewed by the International Liaison Committee on Resuscitation in the previous year. The review this year includes 5 basic life support and 1 paediatric Consensuses on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations. Each of these includes a summary of the science and its quality based on Grading of Recommendations, Assessment, Development, and Evaluation criteria and treatment recommendations. Insights into the deliberations of the International Liaison Committee on Resuscitation task force members are provided in Values and Preferences sections. Finally, the task force members have prioritised and listed the top 3 knowledge gaps for each population, intervention, comparator, and outcome question.

Introduction: The most popular method of training in basic life support and AED use remains instructor-led training courses. This systematic review examines the evidence for different training methods of basic life support providers (laypersons and healthcare providers) using standard instructor-led courses as comparators, to assess whether alternative method of training can lead to effective skill acquisition, skill retention and actual performance whilst using the AED.
Method: OVID Medline (including Medline 1950-November 2010; EMBASE 1988-November 2010) was searched using "training" OR "teaching" OR "education" as text words. Search was then combined by using AND "AED" OR "automatic external defibrillator" as MESH words. Additionally, the American Heart Association Endnote library was searched with the terms "AED" and "automatic external defibrillator". Resuscitation journal was hand searched for relevant articles.
Results: 285 articles were identified. After duplicates were removed, 172 references were reviewed for relevance. From this 22 papers were scrutinized and 18 were included. All were manikin studies. Four LOE 1 studies, seven LOE 2 studies and three LOE 4 studies were supportive of alternative AED training methods. One LOE 2 study was neutral. Three LOE 1 studies provided opposing evidence.
Conclusion: There is good evidence to support alternative methods of AED training including lay instructors, self directed learning and brief training. There is also evidence to support that no training is needed but even brief training can improve speed of shock delivery and electrode pad placement. Features of AED can have an impact on its use and further research should be directed to making devices user-friendly and robust to untrained layperson. (C) 2011 Elsevier Ireland Ltd.

BACKGROUND: Survival after out-of-hospital cardiac arrest (OHCA) is strongly influenced by time to defibrillation. Wider availability of automated external defibrillators (AEDs) may decrease response times but only with increased lay use. Consequently, this study endeavored to improve our understanding of AED use in naive users by measuring times to shock and appropriateness of pad location. We chose sixth-grade students to simulate an extreme circumstance of unfamiliarity with the problem of OHCA and defibrillation. The children's AED use was then compared with that of professionals. METHODS AND RESULTS: With the use of a mock cardiac arrest scenario, AED use by 15 children was compared with that of 22 emergency medical technicians (EMTs) or paramedics. The primary end point was time from entry onto the cardiac arrest scene to delivery of the shock into simulated ventricular fibrillation. The secondary end point was appropriateness of pad placement. All subject performances were videotaped to assess safety of use and compliance with AED prompts to remain clear of the mannequin during shock delivery. Mean time to defibrillation was 90+/-14 seconds (range, 69 to 111 seconds) for the children and 67+/-10 seconds (range, 50 to 87 seconds) for the EMTs/paramedics (P<0.0001). Electrode pad placement was appropriate for all subjects. All remained clear of the

INTRODUCTION: There is evidence that use of automated external defibrillators (AEDs) by laypersons improves rates of survival from cardiac arrest, but there is no consensus on the optimal content and duration of training for this purpose. In this study we examined the use of semiautomatic or automatic AEDs by laypersons who had received no training (intuitive use) and the effects of minimal general theoretical instructions on their performance. METHODS: In a mock cardiac arrest scenario, 236 first year medical students who had not previously attended any preclinical courses were evaluated in their first study week, before and after receiving prespecified instructions (15 min) once. The primary end-point was the time to first shock for each time point; secondary end-points were correct electrode pad positioning, safety of the procedure and the subjective feelings of the students. RESULTS: The mean time to shock for both AED types was 81.2 +/- 19.2 s (range 45-178 s). Correct pad placement was observed in 85.6% and adequate safety in 94.1%. The time to shock after instruction decreased significantly to 56.8 +/- 9.9 s (range 35-95 s; P < or = 0.01), with correct electrode placement in 92.8% and adequate safety in 97%. The students were significantly quicker at both evaluations using the semiautomatic device than with the automatic AED (first evaluation: 77.5 +/- 20.5 s versus 85.2 +/- 17 s, P < or = 0.01; second evaluation: 55 +/- 10.3 s versus 59.6 +/- 9.6 s, P < or = 0.01). CONCLUSION: Untrained laypersons can use semiautomatic and automatic AEDs sufficiently quickly and without instruction. After one use and minimal instructions, improvements in practical performance were significant. All tested laypersons were able to deliver the first shock in under 1 min.

AIM OF THE STUDY: There is consent that the use of automated external defibrillators (AED) by laypersons improves survival rates in case of cardiac arrest, but no evident consensus exists on the content and duration of training for this purpose. Acceptance of the implementation of Public Access Defibrillation programmes will depend on practical and target-oriented training concepts. The aim of this prospective randomised interventional study was to evaluate long-term effects of a specific, minimal training programme on using semiautomatic and fully automatic AEDs in simulated cardiac arrest. MATERIALS AND METHODS: In a mock cardiac arrest scenario 59 medical students with no specific previous medical education were tested during their first semester at medical school. Students who passed any medical emergency training were excluded. The subjects were evaluated before and after attending specified instructions of 15 min duration and after a period of 6 months. Main end points were time to first shock, electrode-positioning and safety throughout the procedure. RESULTS: Mean time to first shock without prior instructions was 77.7+/-17.05 s. After instruction there was a significant improvement to 56.5+/-9.5 s (p

Healthcare staff with the duty to perform CPR should also be capable of using an automated external defibrillator (AED). We investigate whether nurses and physiotherapists can use an AED without prior training. Subjects were tested on a manikin during a cardiac arrest scenario. All 15 untrained subjects could deliver a shock with an AED in 68.8+/-29.2 s (time+/-S.D., range, 40-169 s). Most failed to position the pads correctly (53%) or follow correct safety procedures (67%). After a standardised training session, the time to deliver a shock improved significantly to 48.5+/-5.5 s (range, 41-61 s, P<0.01) and all subjects placed the pads correctly and followed a safe defibrillation procedure. This study shows that nurses and physiotherapists, with no previous AED training, can deliver a shock with an AED. Training improves speed of shock delivery, correct pad placement and safety. This study suggests that it is feasible to train healthcare professionals to use an AED with relatively little training. This should allow rapid deployment of AEDs in those areas of the hospital where cardiac arrests are infrequent and staff do not have rhythm recognition skills.

IMPORTANCE: Out-of-hospital cardiac arrest is a major health problem associated with poor outcomes. Early recognition and intervention are critical for patient survival. Bystander cardiopulmonary resuscitation (CPR) is one factor among many associated with improved survival. OBJECTIVE: To examine temporal changes in bystander resuscitation attempts and survival during a 10-year period in which several national initiatives were taken to increase rates of bystander resuscitation and improve advanced care. DESIGN, SETTING, AND PARTICIPANTS: Patients with out-of-hospital cardiac arrest for which resuscitation was attempted were identified between 2001 and 2010 in the nationwide Danish Cardiac Arrest Registry. Of 29,111 patients with cardiac arrest, we excluded those with presumed noncardiac cause of arrest (n = 7390) and those with cardiac arrests witnessed by emergency medical services personnel (n = 2253), leaving a study population of 19,468 patients. MAIN OUTCOMES AND MEASURES: Temporal trends in bystander CPR, bystander defibrillation, 30-day survival, and 1-year survival. RESULTS: The median age of patients was 72 years; 67.4% were men. Bystander CPR increased significantly during the study period, from 21.1% (95% CI, 18.8%-23.4%) in 2001 to 44.9% (95% CI, 42.6%-47.1%) in 2010 (P < .001), whereas use of defibrillation by bystanders remained low (1.1% [95% CI, 0.6%-1.9%] in 2001 to 2.2% [95% CI, 1.5%-2.9%] in 2010; P = .003). More patients achieved survival on hospital arrival (7.9% [95% CI, 6.4%-9.5%] in 2001 to 21.8% [95% CI, 19.8%-23.8%] in 2010; P < .001). Also, 30-day survival improved (3.5% [95% CI, 2.5%-4.5%] in 2001 to 10.8% [95% CI, 9.4%-12.2%] in 2010; P < .001), as did 1-year survival (2.9% [95% CI, 2.0%-3.9%] in 2001 to 10.2% [95% CI, 8.9%-11.6%] in 2010; P < .001). Despite a decrease in the incidence of out-of-hospital cardiac arrests during the study period (40.4 to 34.4 per 100,000 persons in 2001 and 2010, respectively; P = .002), the number of survivors per 100,000 persons increased significantly (P < .001). For the entire study period, bystander CPR was positively associated with 30-day survival, regardless of witnessed status (30-day survival for nonwitnessed cardiac arrest, 4.3% [95% CI, 3.4%-5.2%] with bystander CPR and 1.0% [95% CI, 0.8%-1.3%] without; odds ratio, 4.38 [95% CI, 3.17-6.06]). For witnessed arrest the corresponding values were 19.4% (95% CI, 18.1%-20.7%) vs 6.1% (95% CI, 5.4%-6.7%); odds ratio, 3.74 (95% CI, 3.26-4.28). CONCLUSIONS AND RELEVANCE: In Denmark between 2001 and 2010, an increase in survival following out-of-hospital cardiac arrest was significantly associated with a concomitant increase in bystander CPR. Because of the co-occurrence of other related initiatives, a causal relationship remains uncertain.

Public access defibrillation initiatives make automated external defibrillators available to the public. This facilitates earlier defibrillation of out-of-hospital cardiac arrest victims and could save many lives. It is currently only used for a minority of cases. The aim of this systematic review was to identify barriers and facilitators to public access defibrillation. A comprehensive literature review was undertaken defining formal search terms for a systematic review of the literature in March 2017. Studies were included if they considered reasons affecting the likelihood of public access defibrillation and presented original data. An electronic search strategy was devised searching MEDLINE and EMBASE, supplemented by bibliography and related-article searches. Given the low-quality and observational nature of the majority of articles, a narrative review was performed. Sixty-four articles were identified in the initial literature search. An additional four unique articles were identified from the electronic search strategies. The following themes were identified related to public access defibrillation: knowledge and awareness; willingness to use; acquisition and maintenance; availability and accessibility; training issues; registration and regulation; medicolegal issues; emergency medical services dispatch-assisted use of automated external defibrillators; automated external defibrillator-locator systems; demographic factors; other behavioural factors. In conclusion, several barriers and facilitators to public access defibrillation deployment were identified. However, the evidence is of very low quality and there is not enough information to inform changes in practice. This is an area in urgent need of further high-quality research if public access defibrillation is to be increased and more lives saved. PROSPERO registration number CRD42016035543.

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.

AIM: To evaluate layperson (university student) ability to use an automated external defibrillator (AED). DESIGN: A repeated measures quasi-experimental study with non-probabilistic sampling and a control group was carried out. SCOPE: Teacher training degree students at the University of Santiago de Compostela (Spain). PARTICIPANTS: The sample consisted of 129 subjects (69% women and 31% men), between 19-47 years of age (mean 23.2+/-4.7 years). As inclusion criterion, the subjects were required to have no previous knowledge of AED. INTERVENTIONS: Times to apply defibrillation with an AED to a mannequin were recorded untrained (T0), after a theoretical and practice explanation lasting less than one minute (T1), and 6 months after the training process (T2). MAIN VARIABLES OF INTEREST: The primary endpoint was the time taken to deliver a defibrillation discharge. The

INTRODUCTION: Growing numbers of public access defibrillators aim to improve the effectiveness of bystander cardiopulmonary resuscitation prior to ambulance arrival. In the UK, however, public access defibrillators are only deployed successfully in 1.7% of out-of-hospital cardiac arrests. We aimed to understand whether this was due to a lack of devices, lack of awareness of their location or a reflection of lack of public knowledge and confidence to use a defibrillator. METHODS: Face-to-face semistructured open quantitative questionnaire delivered in a busy urban shopping centre, to identify public knowledge relating to public access defibrillation. RESULTS: 1004 members of the public aged 9-90 years completed the survey. 61.1% had been first aid trained to a basic life support level. 69.3% claimed to know what an automatic external defibrillator was and 26.1% reported knowing how to use one. Only 5.1% knew where or how to find their nearest public access defibrillator. Only 3.3% of people would attempt to locate a defibrillator in a cardiac arrest situation, and even fewer (2.1%) would actually retrieve and use the device. CONCLUSIONS: These findings suggest that a lack of public knowledge, confidence in using a defibrillator and the inability to locate a nearby device may be more important than a lack of defibrillators themselves. Underused public access defibrillation is a missed opportunity to save lives, and improving this link in the chain of survival may require these issues to be addressed ahead of investing more funds in actual defibrillator installation.

Defibrillation is essential for resuscitating patients with ventricular fibrillation (VF), but shocks often fail to defibrillate. We hypothesized that small variations in pad placement affect shock success, and that defibrillation waveform and shock dose could compensate for suboptimal pad placement. In 10 swine experiments, electrode pads were attached at 3 adjacent anterolateral positions, less than 3 centimeters apart. At each position, 24 episodes of VF were induced and shocked, 8 episodes for each of 3 defibrillation therapies. This resulted in 9 tested combinations of pad position and defibrillation therapy, with 80 episodes of VF for each combination. An episode consisted of 15 seconds of untreated VF, followed by a first shock and, if necessary, a repeat shock. Episodes were separated by four minutes of recovery. Both electrode pad position and therapy order were randomized by experiment. Primary outcome was defined as successful VF termination after the first shock; secondary outcome was the cumulative success of the first and second shocks. First shock efficacy varied widely across the 9 tested combinations of pad position and defibrillation therapy, ranging from 11.3% to 86.3%. When grouped by therapy, first shock efficacy varied significantly between the 3 pad positions: 38.3%, 48.3%, 36.7% (p = 0.02, ANOVA), and, when grouped by pad position, it varied significantly between therapies: 15.0%, 32.5%, 75.8% (p < 0.001, ANOVA). Cumulative 2-shock success varied significantly with therapy (p < 0.001, ANOVA) but not with pad position (p = 0.30, ANOVA). The lowest first shock success was at one position in 6 of 10 animals, at another position in 4 of 10 animals, and never at the third position. Small variations in pad placement can significantly affect defibrillation shock efficacy. However, anatomical variation between individuals and the challenging conditions of real-world resuscitations make optimal pad placement impractical. Suboptimal pad placement can be overcome with defibrillation waveform and shock dose.

BACKGROUND: Correct placement of the left automated external defibrillator (AED) electrode is rarely achieved. AED electrode placement is predominantly illustrated and trained with the rescuer sitting on the right side of the patient. Placement of the AED electrodes from the left side of the patient may result in a better overview of and access to the left lateral side of the thorax. This study aimed to investigate if training in automated external defibrillation on the left side compared to the right side of a manikin improves left AED electrode placement. METHODS: Laypeople attending basic life support training were randomized to learn automated external defibrillation from the left or right side of a manikin. After course completion, participants used an AED and placed AED electrodes in a simulated cardiac arrest scenario. RESULTS: In total, 40 laypersons were randomized to AED training on the left (n=19 [missing data =1], 63% female, mean age: 47.3 years) and right (n=20, 75% female, mean age: 48.7 years) sides of a manikin. There was no difference in left AED electrode placement when trained on the left or right side: the mean (SD) distances to the recommended left AED electrode position were 5.9 (2.1) cm vs 6.9 (2.2) cm (p=0.15) and to the recommended right AED electrode position were 2.6 (1.5) cm vs 1.8 (0.8) cm (p=0.06), respectively. CONCLUSION: Training in automated external defibrillation on the left side of a manikin does not improve left AED electrode placement compared to training on the right side.

BACKGROUND: Correct positioning of defibrillation electrodes is essential to achieve sufficient transmyocardial current to depolarize a critical mass of myocardium, and thus terminate ventricular fibrillation (VF). AIM: To evaluate the pictures on the self-adhesive defibrillation electrodes in guiding laypersons to place the electrodes in the recommended position. METHODS: Defibrillation electrodes from five manufactures (Access Cardio Systems, Schiller, Medtronic, Cardiac Science and Philips) were included in the study and compared with electrodes with a lateral view picture, designed for the study, showing the placement of the apical electrode. A total of 150 laypersons without any experience or training in use of a defibrillator participated in the study. The participants placed randomly selected electrodes on the chest of a resuscitation manikin without any guidance apart from the pictures on the electrodes. The distances of the electrodes from the recommended positions were measured. RESULTS: The proportion of participants who placed both electrodes within 5 cm from recommended position varied from 8% to 36% with the different electrodes. Usually, the apical electrode was placed too anteriorly. Electrodes placed with help of the lateral instruction picture, (designed for the study), showing the placement of the apical electrode were placed significantly more often within 5 cm than any of the others (64%, 95% confidence interval 44-80, P < 0.05). CONCLUSIONS: The current practice in designing pictures on the electrodes does not seem to be optimal in showing the recommended position of the apical electrode as recommended by Guidelines 2000. It is suggested that by showing a lateral view in the instructions, success in placing the apical electrodes correctly can be improved.

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.

Abstract

Objective

Our study evaluates the impact of features of automated external defibrillators (AEDs) on the performance and speed of untrained laypersons to deliver a shock and initiate CPR after a shock.

Methods

This was a randomized trial of volunteer laypersons without AED or advanced medical training. Subjects were assigned to use one of six different models of AEDs on a manikin in simulated cardiac arrest. No instructions on AED operation were provided. Primary endpoints were shock delivery and elapsed time from start to shock. Secondary endpoints included time to power-on, initiation of CPR, adequacy of pad placement and subjects’ ratings of ease of use (1 = very easy, 5 = very difficult).

Results

Most subjects (109/120; 91%) were able to deliver a shock. Median time from start of scenario to shock delivery was 79 s (IQR: 67–99). Of the 11 participants who did not deliver shock, eight never powered on the device. Time to power-on was shorter in devices with open lid (median 12 s, IQR 8–27 s) and pull handle (17 s, IQR 9–20 s) mechanisms than with a push button (37 s, IQR 18–69 s; p = 0.000). Pad position on the manikin was judged adequate for 86 (77%) of the 111 subjects who placed pads. Devices which gave more detailed voice instruction for pad placement had higher rates of adequate pad position [38/39 (97%) versus 50/73 (68%), p = 0.001]. With AEDs that provided step-by-step CPR instruction, 49/58 (84%) subjects began CPR compared to 26/51 (51%) with AEDs that only prompted to start CPR (p = 0.01). Participants rated all the models easy to use (overall mean 1.48; individual device means 1.28–1.71).

Conclusions

Most untrained laypersons were successful in delivering a shock. Device features had the most impact on these functions: ability and time to power-on device, adequacy of pad position and initiation of CPR.

Abstract

Study Objective: This study evaluated the differences in efficacy of 2 methods for training seniors in the use of an automated external defibrillator (AED). We tested the hypothesis that each training method (face-to-face instruction compared with video-based instruction) would result in similar AED performance on a manikin. Methods: Two hundred ten seniors from various senior centers were randomized to receive face-to-face or video-based instruction on AED skills. Seniors were assessed individually and tested on the speed and quality of AED performance. We retested 177 of these initial trainees 3 months after initial training. Similar performance measures were assessed. Results: Although there were statistically significant differences between the 2 training methods in terms of average time to shock at both evaluations, the results in general demonstrate that there were no clinically meaningful distinctions (time differences of <20 seconds) between the AED performance of seniors trained with a video and seniors trained in a face-to-face setting at the initial training or at the retention assessment. At the initial evaluation, overall performance was satisfactory, with greater than 98% trained with either method delivering a shock. However, at the 3-month follow-up, almost one fourth of trainees were not able to deliver a shock, and almost half were not able to correctly place the pads on the manikin. Conclusion: We believe that seniors can be trained equally well in AED performance with video-based self-instruction or face-to-face instruction. How to maintain acceptable AED performance skills over time remains a challenge. [Meischke HW, Rea T, Eisenberg MS, Schaeffer SM, Kudenchuk P. Training seniors in the operation of an automated external defibrillator: a randomized trial comparing two training methods. Ann Emerg Med. September 2001;38:216-222.]

OBJECTIVE: This study examined the effect of three types of brief training on the use of automatic external defibrillators (AEDs) by 43 lay users. BACKGROUND: Because AEDs were recently approved for home use, brief training for nonprofessional users needs investigation. METHOD: During training, the exposure training group read an article about AEDs that provided no information on how to operate them; the low-training group inspected the AED and read the operating instructions in the paper-based manual but was not allowed to use the device; and the high-training group watched a training video and performed a mock resuscitation using the AED but no manikin. All participants returned 2 weeks later and performed a surprise simulated AED resuscitation on a manikin. RESULTS: Most participants in each training group met criteria of minimally acceptable performance during the simulated manikin resuscitation, as measured by time to first shock, pad placement accuracy, and safety check performance. All participants who committed errors were able to successfully recover from them to complete the resuscitation. Compared with exposure training, the low and high training had a beneficial effect on time to first shock and errors. CONCLUSION: Untrained users were able to adequately use this AED, demonstrating walk-up-and-use usability, but additional brief training improved user performance. APPLICATION: This study demonstrated the importance of providing high-quality but brief training for home AED users. In conjunction with other findings, the current study helps demonstrate the need for well-designed training for consumer medical devices.

BACKGROUND: The time to skill deterioration between primary training/retraining and further retraining in cardiopulmonary resuscitation (CPR) and automated external defibrillation (AED) for lay-persons is unclear. The Public Access Defibrillation (PAD) trial was a multi-center randomized controlled trial evaluating survival after CPR-only versus CPR+AED delivered by onsite non-medical volunteer responders in out-of-hospital cardiac arrest. AIMS: This sub-study evaluated the relationship of time between primary training/retraining and further retraining on volunteer performance during pretest AED and CPR skill evaluation. METHODS: Volunteers at 1260 facilities in 24 North American regions underwent training/retraining according to facility randomization, which included an initial session and a refresher session at approximately 6 months. Before the next retraining, a CPR and AED skill test was completed for 2729 volunteers. Primary outcome for the study was assessment of global competence of CPR or AED performance (adequate versus not adequate) using chi(2)-test for trends by time interval (3, 6, 9, and 12 months). Confirmatory (GEE) logistic regression analysis, adjusted for site and potential confounders was done. RESULTS: The proportion of volunteers judged to be competent did not diminish by interval (3, 6, 9, and 12 months) for either CPR or AED skills. After adjusting for site and potential confounders, longer intervals to further retraining was associated with a slightly lower likelihood of performing adequate CPR but not with AED scores. CONCLUSIONS: After primary training/retraining, the CPR skills of targeted lay responders deteriorate nominally but 80% remain competent up to 1 year. AED skills do not deteriorate significantly and 90% of volunteers remain competent up to 1 year.

AIM: To determine the optimal refresher training interval for lay volunteer responders in the English National Defibrillator Programme who had previously undertaken a conventional 4-h initial class and a first refresher class at 6 months. METHODS: Subjects were randomised to receive either two additional refresher classes at intervals of 7 and 12 months or one additional refresher class after 12 months. RESULTS: Greater skill loss had occurred when the second refresher class was undertaken at 12 compared with 7 months. Skill retention however, was higher in the former group, ultimately resulting in no significant difference in final skill performance. There was no significant difference in performance between subjects attending two versus three refresher classes. On completion of refresher training all subjects were able to deliver countershocks, time to first shock decreased by 17s in both groups, and the proportion of subjects able to perform most skills increased. The execution of several important interventions remained poor, regardless of the total number of classes attended or the interval between them. These included CPR skills, defibrillation pad placement, and pre-shock safety checks. Refresher classes held more frequently and at shorter intervals increased subjects' self-assessed confidence, possibly indicating greater preparedness to use an AED in a real emergency. CONCLUSIONS: This study shows that the ability to deliver countershocks is maintained whether the second refresher class is held at seven or 12 months after the first. To limit skill deterioration between classes, however, refresher training intervals should not exceed 7 months. The quality of instruction given should be monitored carefully. Learning and teaching strategies require review to improve skill acquisition and maintenance.

AIM: To determine the effect of a new automated external defibrillator (AED) system connected by General Packet Radio Service (GPRS) to an external call centre in assisting novices in a sudden cardiac arrest situation. METHOD: Prospective, interventional study. Layperson volunteers were first asked to complete a survey about their knowledge and ability to give cardiopulmonary resuscitation (CPR) and use an AED. A simulated cardiac arrest scenario using a CPR manikin was then presented to volunteers. A telephone and semi-AED were available in the same room. The AED was linked to a call centre, which provided real-time information to 'bystanders' and emergency services via GPRS/GPS technology. The scene was videotaped to avoid any interaction with examiners. A standardised check list was used to record correct actions. RESULTS: 85 volunteers completed questionnaires and were recorded. Mean age was 44+/-16, and 49% were male; 38 (45%) had prior CPR training or felt comfortable intervening in a sudden cardiac arrest victim; 40% felt they could deliver a shock using an AED. During the scenarios, 56 (66%) of the participants used the AED and 53 (62%) successfully delivered an electrical shock. Mean time to defibrillation was 2 min 29 s. Only 24 (28%) participants dialled the correct emergency response number (112); the live-assisted GPRS AED allowed alerted emergency services in 38 other cases. CPR was initiated in 63 (74%) cases, 26 (31%) times without prompting and 37 (44%) times after prompting by the AED. CONCLUSIONS: Although knowledge of the general population appears to be inadequate with regard to AED locations and recognition, live-assisted devices with GPS-location may improve emergency care.