Community approaches to improve resuscitation after out-of-hospital sudden cardiac arrest.

Sudden cardiac arrest (SCA) is a major cause of mortality in North America and other westernized societies, accounting for ≈10% of all deaths and up to 50% of heart disease–related death.1,2 The condition is characterized by an unexpected cardiovascular collapse due to an underlying cardiac cause.3 This definition, although useful as an intellectual foundation, is challenged by operational translation. The challenge of deriving a working case definition for SCA is important because different approaches for ascertainment and classification can influence efforts aimed at estimating incidence, improving prevention strategies, or directing resuscitation care. For example, various strategies may be used to determine incidence. Death certificates, emergency medical services (EMS) records, witness interviews, medical records, and medical examiner reports can be used singly or in combination to ascertain and classify SCA. Each approach has strengths and limitations. Death certificate ascertainment and classification, for example, are efficient and can be defined by specific objective coding criteria but often overestimate incidence because the approach includes people who do not die suddenly or do not truly die from cardiac causes.4 Conversely, death certificates exclude people who were successfully resuscitated. Thus, the “best” strategy for SCA ascertainment and classification depends in large part on the intent of the effort and available resources. The present clinical summary discusses approaches to improve resuscitation of out-of-hospital SCA and therefore focuses on SCA treated by EMS. From an epidemiological perspective, EMS-treated, out-of-hospital SCA constitutes a subset of all heart disease death events. As such, it excludes in-hospital events and out-of-hospital events that either do not have an emergency response or receive a response but no EMS treatment. The latter circumstance arises typically when there are signs of prolonged, irreversible death or when there is a “do not resuscitate” request and documentation.5 Although community-specific heterogeneity exists with …