Improving survival from sudden cardiac arrest - The role of the automated external defibrillator

Context Sudden cardiac death is a major public health problem in the United States, and improving survival after out-of-hospital cardiac arrest has be en the subject of intense study. Early defibrillation has been shown to be critical to improving survival. Use of automated external defibrillators (A EDs) has become an important component of emergency medical systems, and re cent advances in AED technology have allowed expansion of AED use to nontra ditional first responders and the lay public. Objectives To examine advancements in AED technology, review the impact of AEDs on time to defibrillation and survival, and explore the future role of AEDs in the effort to improve survival following sudden cardiac arrest. Data Sources MEDLINE was searched for articles from 1966 through December 2 000 (Medical Subject Headings: electric countershock, heart arrest, resusci tation, emergency medical services; keywords: automatic external defibrilla tor, automated external defibrillator, public access defibrillation). Refer ence lists of relevant articles, news releases, and product information fro m manufacturers were also reviewed. Study Selection Initial MEDLINE search produced 4816 articles, from which 1 01 articles were selected for referencing based on having been published in a peer-reviewed journal and on relevance to the subject of the manuscript as determined by all 5 authors. Data Extraction All studies were critically reviewed for relevance, accurac y, and quality of data and study design by all authors. Data Synthesis Recent advances in AED technology and design have resulted i n marked simplification of AED operation, improvements in accuracy and effe ctiveness, and reductions in cost. Use of AEDs by first responders and layp ersons has reduced time to defibrillation and improved survival from sudden cardiac arrest in several communities. Initial studies of the cost-effecti veness of AED use in comparison with other commonly used treatments are fav orable. Conclusion The AED represents an efficient method of delivering defibrillat ion to persons experiencing out-of-hospital cardiac arrest and its use by b oth traditional and nontraditional first responders appears to be safe and effective. The rapidly expanding role of AEDs in traditional emergency medi cal systems is supported by the literature, and initial studies of public a ccess to defibrillation offer hope that further improvements in survival af ter sudden cardiac death can be achieved.