Public Access Defibrillation Trial Research Articles

SURVIVAL OF OUT-OF-HOSPITAL CARDIAC ARRESTS

Each year, about 300,000 Americans have an out-of-hospital cardiac arrest assessed by emergency medical services (EMS), with an estimated median national survival rate of approximately 8 percent. 1 American Heart Association Heart and stroke statistics: 2010 update—a report from the American Heart Association. Circulation. 2010; 121: e46-e215 Crossref PubMed Scopus (1388) Google Scholar A large multicenter community-based clinical trial showed that laypeople can use automated external defibrillators (AEDs) safely and effectively in public settings. 2 Hallstrom AP Omato JP Weisfeldt M Public Access Defibrillation Trial Investigators et al. Public-access defibrillation and survival after out-of-hospital cardiac arrest. N Engl J Med. 2004; 351: 637-646 Crossref PubMed Scopus (937) Google Scholar However, there is evidence that in comparison with conventional resuscitation, access to a home AED does not improve overall survival significantly. 3 Bardy GH Lee KL Mark DB et al. Home use of automated external defibrillators for sudden cardiac arrest. N Engl J Med. 2008; 358: 1793-1804 Crossref PubMed Scopus (231) Google Scholar Weisfeldt and colleagues conducted a study to determine if there was an association between location of cardiac arrest, type of arrhythmia and probability of survival.

Part 6: Electrical Therapies

The recommendations for electrical therapies described in this section are designed to improve survival from SCA and life-threatening arrhythmias. Whenever defibrillation is attempted, rescuers must coordinate high-quality CPR with defibrillation to minimize interruptions in chest compressions and to ensure immediate resumption of chest compressions after shock delivery. The high first-shock efficacy of newer biphasic defibrillators led to the recommendation of single shocks plus immediate CPR instead of 3-shock sequences that were recommended prior to 2005 to treat VF. Further data are needed to refine recommendations for energy levels for defibrillation and cardioversion using biphasic waveforms.

Survival After Application of Automatic External Defibrillators Before Arrival of the Emergency Medical System: Evaluation in the Resuscitation Outcomes Consortium Population of 21 Million

The purpose of this study was to assess the effectiveness of contemporary automatic external defibrillator (AED) use. In the PAD (Public Access Defibrillation) trial, survival was doubled by focused training of lay volunteers to use an AED in high-risk public settings. We performed a population-based cohort study of persons with nontraumatic out-of-hospital cardiac arrest before emergency medical system (EMS) arrival at Resuscitation Outcomes Consortium (ROC) sites between December 2005 and May 2007. Multiple logistic regression was used to assess the independent association between AED application and survival to hospital discharge. Of 13,769 out-of-hospital cardiac arrests, 4,403 (32.0%) received bystander cardiopulmonary resuscitation but had no AED applied before EMS arrival, and 289 (2.1%) had an AED applied before EMS arrival. The AED was applied by health care workers (32%), lay volunteers (35%), police (26%), or unknown (7%). Overall survival to hospital discharge was 7%. Survival was 9% (382 of 4,403) with bystander cardiopulmonary resuscitation but no AED, 24% (69 of 289) with AED application, and 38% (64 of 170) with AED shock delivered. In multivariable analyses adjusting for: 1) age and sex; 2) bystander cardiopulmonary resuscitation performed; 3) location of arrest (public or private); 4) EMS response interval; 5) arrest witnessed; 6) initial shockable or not shockable rhythm; and 7) study site, AED application was associated with greater likelihood of survival (odds ratio: 1.75; 95% confidence interval: 1.23 to 2.50; p < 0.002). Extrapolating this greater survival from the ROC EMS population base (21 million) to the population of the U.S. and Canada (330 million), AED application by bystanders seems to save 474 lives/year. Application of an AED in communities is associated with nearly a doubling of survival after out-of-hospital cardiac arrest. These results reinforce the importance of strategically expanding community-based AED programs.

Two simple questions to assess neurologic outcomes at 3 months after out-of-hospital cardiac arrest: Experience from the Public Access Defibrillation Trial

Background Two simple questions have been used to classify neurologic outcome in patients with stroke. Could they be similarly applied to patients with cardiac arrest? Methods As part of a randomized trial, study personnel interviewed by telephone survivors of out-of-hospital cardiac arrest to assess their outcomes 3 months after discharge. They asked two simple questions: (1) In the last 2 weeks, did you require help from another person for your everyday activities? and (2) Do you feel that you have made a complete mental recovery form your heart arrest? Next they administered the Mini-Mental State Examination (MMSE) from the Adult Lifestyles and Function Interview (ALFI) to assess cognition on a scale from 0 to 22 and the Health Utilities Index Mark 3 (HUI3) to assess quality of life on a scale from 0 (death) to 1 (perfect health). Results Based on responses to the two simple questions, 32 survivors were classified as dependent ( n = 5, 16%), independent ( n = 3, 9%) and full recovery ( n = 24, 75%). The mean ALFI-MMSE score was 19.1 (standard deviation 5.1), and the mean HUI3 score was 0.76 (standard deviation 0.28). The classification based on the two simple questions was significantly correlated with ALFI-MMSE ( p = 0.002) and HUI3 ( p = 0.001). Scores for the HUI3 were missing in eight survivors. Conclusions Neurologic outcomes based on the two simple questions after cardiac arrest can be easily determined, sensibly applied, and readily interpreted. These preliminary findings justify further evaluation of this simple and practical approach to classify neurologic outcome in survivors of cardiac arrest.

Performance of chest compressions by laypersons during the Public Access Defibrillation Trial

Background Increasing evidence indicates that health professionals often may not achieve guideline standards for cardiopulmonary resuscitation (CPR). Little is known about layperson CPR performance. Methods The investigation was a retrospective cohort study of cardiac arrest patients treated by layperson CPR and one model of automated external defibrillator (AED) as part of the Public Access Defibrillation Trial ( n = 26). CPR was measured using software that integrates the event log, ECG signal, and thoracic impedance signal. We assessed chest compression fraction (proportion of attempted resuscitation spent performing chest compressions), prompted compression fraction (proportion of attempted resuscitation spent performing compressions during AED-prompted periods), compression rate, and compressions per minute. Results Of the 26 cases, 13 presented with ventricular fibrillation and 13 with nonshockable rhythms. Overall, during the period when patients did not have spontaneous circulation, the median chest compression fraction was 34% (IQR 17–48%), median prompted chest compression fraction was 49% (IQR 30–66%), and the median chest compression rate was 96/min (IQR 90–110/min). Taken together, the median chest compression delivered per minute among all arrests was 29 (IQR 20–42). CPR characteristics differed according to initial rhythm: median chest compression per minute was 20 (IQR 13–29) among ventricular fibrillation and 42 (IQR 28–47) among nonshockable rhythms ( p = 0.003). Conclusions In this study of trained laypersons, CPR varied substantially and often did not achieve guideline parameters. The findings suggest a need to improve CPR training, consider changes to CPR protocols, and/or improve the AED–rescuer interface.

Public Access Defibrillation

Sudden cardiac arrest (SCA) is recognized as a serious public health problem, accounting for 250 000 to 300 000 deaths per year; it is now the third-leading cause of death behind cancer and nonsudden cardiovascular deaths.1,2 Immediate, well-performed cardiopulmonary resuscitation (CPR) and early defibrillation are the only out-of-hospital interventions that improve outcomes.3 The chain of survival relies on lay responders and emergency medical services (EMS) to initiate the potentially life-saving procedures of CPR and defibrillation. Articles see pp 510 and 518 In 1994, the American Heart Association (AHA) convened the first conference on public access defibrillation (PAD) to introduce the strategy of placing easy-to-use defibrillators in public places to decrease the death rate from SCA.4 Specific recommendations encouraged the stakeholders (the AHA, the US Food and Drug Administration, the National Institutes of Health, industry, and communities) to facilitate PAD by developing user-friendly, less-expensive automated external defibrillators (AEDs); testing the concept within large clinical trials; and organizing communities to promote and support effective PAD programs. Widespread CPR and AED training of the public was emphasized. In the ensuing 15 years, many of these recommendations have been heeded, and PAD programs are now commonplace. The National Institutes of Health–sponsored PAD trial demonstrated that survival doubled when events occurred in communities equipped and trained with CPR and AEDs compared with CPR alone.5 Within the Resuscitations Outcomes Consortium (ROC), out-of-hospital cardiac arrest victims had a markedly increased chance of survival if the first shock was delivered by a bystander using an AED rather than by EMS.6 PAD programs in airports, airlines, and casinos have also validated the effectiveness of the concept. Out-of hospital cardiac arrest is treatable, and outcomes can be improved with currently available approaches. Multiple locations have been recognized as having a higher incidence of cardiac arrest …

Cardiopulmonary resuscitation – automated external defibrillation programs for children and adolescents: Is public access defibrillation directed at our youth justifiable?

Cardiopulmonary resuscitation – automated external defibrillation programs for children and adolescents: Is public access defibrillation directed at our youth justifiable?

The effect of time on CPR and automated external defibrillator skills in the Public Access Defibrillation Trial

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. 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. 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. 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. 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.

Cost-effectiveness of automated external defibrillators in public places: con

To discuss the clinical effectiveness, public health impact and cost-effectiveness of public access defibrillation. High rates of survival from prehospital ventricular fibrillation have been documented in patients treated by first responders using automated external defibrillators. The recent Public Access Defibrillation trial demonstrated a doubling of cardiac arrest survival in community units where volunteers trained in cardiopulmonary resuscitation were additionally equipped with automated external defibrillators. The cost-effectiveness analysis of the Public Access Defibrillation trial has not yet been published, and previous analyses have lacked full data on cost, outcome, or both. Data from many sources indicate that automated external defibrillator placement at sites with an expected rate of one cardiac arrest per defibrillator per 5 years, as recommended by the American Heart Association, addresses only around 1-2% of prehospital arrests, and will have a minimal impact on population survival. While highly targeted provision of automated external defibrillators in areas of greatest risk, such as casinos and airports, may be cost-effective, it will have little impact at a population level. Provision of more widespread public access defibrillation to sites with lower incidence of cardiac arrest is unlikely to be cost-effective, and may represent poorer value for money than alternative healthcare interventions in coronary artery disease.

Characteristics of volunteers responding to emergencies in the Public Access Defibrillation Trial

To evaluate the characteristics of volunteers responding to emergencies in the North American Public Access Defibrillation (PAD) Trial. The PAD Trial was a prospective evaluation of cardiac arrest survival in community facilities randomized to cardiopulmonary resuscitation (CPR) or to CPR with automated external defibrillators (AEDs). The PAD volunteers' characteristics were analyzed using Poisson regression clustered on the facility and offset by the number of emergency episodes to which volunteers were exposed. A total of 19,320 volunteers in 1260 facilities were trained to provide emergency care. Of these, 8169 volunteers were participating actively at their facility during a time when one or more emergency episodes occurred. There were 1971 emergency episodes responded to by 1245 volunteers. The treatment arm (CPR-only versus CPR+AED) was not associated with the likelihood of volunteer participation in an episode. Likewise, the volunteers' age or sex did not affect response. Volunteers more likely to respond were supervisory/management or security personnel, non-minority participants, volunteers with previous CPR training, volunteers with previous experience in emergency care and those who passed the PAD CPR skills follow-up test. Volunteers who had a formal education beyond a high school level were less likely to respond. Volunteers with previous emergency training and positions of responsibility in their facility had a greater likelihood of participation in medical emergencies in the PAD Trial.

Adverse events associated with lay emergency response programs: The public access defibrillation trial experience

The adverse event (AE) profile of lay volunteer CPR and public access defibrillation (PAD) programs is unknown. We undertook to investigate the frequency, severity, and type of AE's occurring in widespread PAD implementation. A randomized-controlled clinical trial. One thousand two hundred and sixty public and residential facilities in the US and Canada. On-site, volunteer, lay personnel trained in CPR only compared to CPR plus automated external defibrillators (AEDs). Persons experiencing possible cardiac arrest receiving lay volunteer first response with CPR+AED compared with CPR alone. An AE is defined as an event of significance that caused, or had the potential to cause, harm to a patient or volunteer, or a criminal act. AE data were collected prospectively. Twenty thousand three hundred and ninety six lay volunteers were trained in either CPR or CPR+AED. One thousand seven hundred and sixteen AEDs were placed in units randomized to the AED arm. There were 26,389 exposure months. Only 36 AE's were reported. There were two patient-related AEs: both patients experienced rib fractures. There were seven volunteer-related AE's: one had a muscle pull, four experienced significant emotional distress and two reported pressure by their employee to participate. There were 27 AED-related AEs: 17 episodes of theft involving 20 devices, three involved AEDs that were placed in locations inaccessible to the volunteer, four AEDs had mechanical problems not affecting patient safety, and three devices were improperly maintained by the facility. There were no inappropriate shocks and no failures to shock when indicated (95% upper bound for probability of inappropriate shock or failure to shock = 0.0012). AED use following widespread training of lay-persons in CPR and AED is generally safe for the volunteer and the patient. Lay volunteers may report significant, usually transient, emotional stress following response to a potential cardiac arrest. Within the context of this prospective, randomized multi-center study, AEDs have an exceptionally high safety profile when used by trained lay responders.

Stress reactions and perceived difficulties of lay responders to a medical emergency

Bystander CPR rates remain low. One reason may be that the thought of responding to an emergency is so stressful that it decreases the willingness of laypersons to respond. The purpose of this study was to quantify the amount of stress experienced by lay responders to a medical emergency and to identify barriers that may have impeded their response to the event. Responses from 1243 laypersons responding to an emergency during the Public Access Defibrillation Trial were analyzed in a mixed methods study. Stress related to the event was recorded using a 0 (none) to 5 (severe) scale. Qualitative responses to the question of "What was most difficult?" about the event were analyzed using content analysis. Reported stress levels were low overall (mean 1.2, median 1.0). Laypersons responding to an emergency presumed to be a cardiac arrest had higher stress than those involved in other events (median 2.0 versus 1.0). Stress levels were higher in residential than in public settings (mean 1.41, median 1.0 versus mean 1.13, median 1.0). Those who fit a certain profile (females, non-native English speakers) reported statistically higher stress levels than others. A total of 614 qualitative responses were studied and aggregated into four major categories of difficulty: practical issues; characteristics of the victim; interpersonal issues; thoughts and feelings of the lay responder. Most difficulties were in the category of practical issues. Among these study volunteer lay responders, low levels of stress were reported. Incorporating descriptions of the difficulties experienced by lay responders in CPR/AED training curricula may make courses more realistic and useful.

Automated External Defibrillator Program Does Not Impair Cardiopulmonary Resuscitation Initiation in the Public Access Defibrillation Trial

To evaluate whether automated external defibrillator (AED) training and AED availability affected the response of volunteer rescuers and performance of cardiopulmonary resuscitation (CPR) in presumed out-of-hospital cardiac arrest (OOH-CA) during the multicenter Public Access Defibrillation Trial. The Public Access Defibrillation Trial recruited 1,260 facilities in 24 North American regional sites to participate in a trial addressing survival from OOH-CA when AED training and availability were added to a volunteer-based emergency response team. Volunteers at each facility were trained to perform either CPR alone (CPR) or CPR in conjunction with AED use (CPR+AED) according to randomized assignments. This study reports the frequency of response and initiation of CPR actions (chest compressions and/or ventilations) by volunteers in the CPR and CPR+AED study groups. A total of 314 presumed OOH-CA episodes occurred in CPR facilities, and 308 occurred in CPR+AED facilities. The volunteers were matched well for age, gender, and other features. Overall, ventilations (23.1% vs. 13.1%), chest compressions (24.4% vs. 12.1%), and both actions (19.8% vs. 10.5%; all p < 0.05) were more commonly performed in OOH-CA cases in the CPR+AED group. However, when only OOH-CA cases with volunteers responding were analyzed, the rates of CPR actions were similar. In the subgroup of CPR+AED cases with a responding volunteer, the AED was turned on for only 47% of cases. Volunteers initiated a CPR action more commonly when the AED was turned on (60.7% vs. 39.3%; p = 0.003). In the Public Access Defibrillation Trial, rates of CPR actions for presumed OOH-CA victims were low but similar for CPR and CPR+AED responding volunteer rescuers. Factors associated with volunteer response, CPR action initiation, and AED activation warrant further investigation.

Automated External Defibrillator Program Does Not Impair Cardiopulmonary Resuscitation Initiation in the Public Access Defibrillation Trial

Automated External Defibrillator Program Does Not Impair Cardiopulmonary Resuscitation Initiation in the Public Access Defibrillation Trial

Evaluation of Community Consultation and Public Disclosure in the New York City Public Access Defibrillation (PAD) Trial

Evaluation of Community Consultation and Public Disclosure in the New York City Public Access Defibrillation (PAD) Trial

How Well are Cardiopulmonary Resuscitation and Automated External Defibrillator Skills Retained over Time? Results from the Public Access Defibrillation (PAD) Trial

The current standard for cardiopulmonary resuscitation (CPR) and automated external defibrillator (AED) retraining for laypersons is a four-hour course every two years. Others have documented substantial skill deterioration during this time period. To evaluate 1) the retention of core CPR and AED skills among volunteer laypersons and 2) the time required to retrain laypersons to proficiency as a function of time since initial training. This was an observational follow-up study evaluating CPR and AED skill retention and testing/retraining time up through 17 months after initial training. The study took place at 1,260 facilities recruited by 24 North American clinical research centers, and included 6,182 volunteer laypersons participating in the Public Access Defibrillation (PAD) Trial. Training to proficiency in either CPR only (N = 2,426) or CPR+AED (N = 3,756) was followed by testing/retraining provided three to 17 months later. Retraining was done in brief, one-on-one, individualized, interactive sessions. The outcome studied was instructors' global assessments of performance of CPR and AED skill adequacy, i.e., whether CPR actions would likely result in perfusion (yes/no) and whether AED actions would result in a shock through the heart (yes/no). For global CPR performance, 79%, 73%, and 71% of volunteers tested for the first time since initial training three to five, six to 11, and 12 to 17 months after initial training, respectively, were judged by their instructors as having adequate performance (p < 0.001, chi-square for linear trend). For global AED performance, 91%, 86%, and 84% of volunteers, respectively, were judged as having adequate performance (p < 0.001). The mean (+/- standard deviation) times required to test and retrain volunteers to proficiency were 5.7 (+/- 4.0) minutes for CPR skills and 7.7 (+/- 4.6) minutes for CPR+AED skills. Among PAD Trial volunteer laypersons participating in a simulated resuscitation, the proportions of volunteers judged by instructors to have adequate CPR and AED skills demonstrated small declines associated with longer intervals between initial training and subsequent testing. However, based on instructors' judgment, large majorities of volunteers still retained both CPR and AED core skills through 17 months after initial training. Furthermore, individual testing and retraining for CPR and AED skills were usually accomplished in less than 10 minutes per volunteer. Additional research is essential to identify training and evaluation techniques that predict adequate CPR and AED skill performance of laypersons when applied to an actual cardiac arrest.

How Well are Cardiopulmonary Resuscitation and Automated External Defibrillator Skills Retained over Time? Results from the Public Access Defibrillation (PAD) Trial

How Well are Cardiopulmonary Resuscitation and Automated External Defibrillator Skills Retained over Time? Results from the Public Access Defibrillation (PAD) Trial

Location of Cardiac Arrests in the Public Access Defibrillation Trial

Background. The Public Access Defibrillation (PAD) Trial found an overall doubling in the number of out-of-hospital cardiac arrest (CA) survivors when a lay responder team was equipped with an automated external defibrillator (AED), compared with cardiopulmonary resuscitation (CPR) alone. Objectives. To describe the types of facilities that participated in the trial andto report the incidence of CA andsurvival in these different types of facilities. Methods. In this post-hoc analysis of PAD Trial data, the physical characteristics of the participating facilities andthe numbers of presumed CAs, treatable CAs, andsurvivors are reported for each category of facilities. Results. There were 625 presumed CAs at 1,260 participating facilities. Just under half (n = 291) of the presumed CAs were classified as treatable CAs. Treatable CAs occurred at a rate of 2.9 per 1,000 person-years of exposure; rates were highest in fitness centers (5.1) andgolf courses (4.8) andlowest in office complexes (0.7) andhotels (0.7). Survival from treatable CA was highest in recreational complexes (0.5), public transportation sites (0.4), andfitness centers (0.4) andlowest in office complexes (0.1) andresidential facilities (0.0). Conclusions. During the PAD Trial, the exposure-adjusted rate of treatable CA was highest in fitness centers andgolf courses, but the incidence per facility was low to moderate. Survival from treatable cardiac arrest was highest in recreational complexes, public transportation facilities, andfitness centers.

Part 1: Introduction

Part 1: Introduction

Major Changes in the 2005 AHA Guidelines for CPR and ECC

The emergency cardiovascular care (ECC) scientists involved in the 2005 evidence evaluation process and the revision of the 2005 AHA Guidelines for CPR and ECC began and ended the process aware of the limitations of the resuscitation scientific evidence, optimistic about emerging data that documents the benefits of high-quality cardiopulmonary resuscitation (CPR), and determined to make recommendations that would increase survival from cardiac arrest and life-threatening emergencies. This editorial summarizes the factors that contributed to the tipping point, the point at which information and discussion either triggered support for major changes in the guidelines or reaffirmed existing recommendations. The scientists critically reviewed the sequence and priorities of the steps of CPR to identify those factors with the greatest potential impact on survival. They then developed recommendations to support those interventions that should be performed frequently and well. There was unanimous support for increased emphasis on ensuring that rescuers deliver high-quality CPR: rescuers need to provide an adequate number and depth of compressions, allow complete chest recoil after each compression, and minimize interruptions in chest compressions. The 2005 AHA Guidelines for CPR and ECC are based on the most comprehensive review of resuscitation literature ever published.1 The evidence evaluation process incorporated the input of 281 international resuscitation experts who evaluated research, topics, and hypotheses over a 36-month period before the 2005 Consensus Conference. The process included structured evidence evaluation, analysis, and documentation of the literature.2 It also included rigorous disclosure and management of potential conflicts of interest, a process summarized in two editorials.3,4 Cardiopulmonary resuscitation and emergency cardiovascular care is a relatively new field. The epidemiologic data is incomplete, and high-level evidence is insufficient to support many recommendations. Although sudden cardiac arrest (SCA) is responsible for an estimated 250 000 deaths out of the hospital in the United …