Out-of-Hospital Cardiac Arrest in Bariloche: Incidence, Distribution and Context. Evaluation of the Potential Usefulness of an Automated External Defibrillator Program

Background: The incidence and distribution of potentially resuscitable out-of-hospital cardiac arrests in a community shouldbe determined before implementing an automated external defibrillator program in order to anticipate its effectiveness.Objectives: The aims of this study were: 1) to determine the annual incidence, distribution and context of out-of-hospitalcardiac arrest in the city of Bariloche; and 2) to evaluate the potential usefulness of an AED program in the city, in publiclocations or in the patients’ homes according to the information obtained.Methods: A retrospective registry of out-of-hospital cardiac arrests was carried out in the setting of the REGIBAR study duringone year, using The Civil Registry as source of information. The cases of myocardial infractions hospitalized and presenting ascardiac arrest prior to arrival at hospital were also analyzed. Verbal autopsies were performed to determine if the death wasdue to cardiovascular disease and to determine its context. Out-of-hospital cardiac arrests were classified as those occurring within the patient’s home or in public locations. The presence of co-habitants and witnesses of cardiac arrests occurring athome and the history of myocardial infarction/heart failure were recorded.Results: During the study period, 61 out-of-hospital cardiac arrests occurred (age: 78.3; range: 47-100), 40% were womenand 52% were ≥80 years. Incidence: 53/100, 000 person-years. None of the cases of cardiac arrest prior to arrival at hospitalundergoing resuscitation arrived alive at hospital. Prior myocardial infarction/heart failure was present in 11.5% (7/61) of thecases. Sixty cardiac arrests occurred at home and one took place in a public space. The emergency medical service system wascontacted in 20% of the cases and 10% of the cases underwent cardiopulmonary resuscitation. Seventy-five percent (45/60)of the subjects who experienced cardiac arrests at home were not living alone, but their co-habitants witnessed the event inonly 12% (7/60) of the cases.Conclusions: The incidence of out-of-hospital cardiac arrest in Bariloche was 53/100,000 person-years. Only one case occurredin a public space.An emergency medical service attended 1 out of 5 cases and half of these cases underwent cardiopulmonary resuscitation.None of the cases of out-of-hospital cardiac arrest arrived alive at hospital.Only 1 of 10 cardiovascular deaths at home was witnessed.The implementation of an automated external defibrillator program does not represent an advisable strategy in Bariloche.