Monitoring intervention programmes for out-of-hospital cardiac arrest in a mixed urban and rural setting

Abstract

Only a few data are available on the survival rate following out-of-hospital cardiac arrest in different Italian settings. We report an analysis of a 10-year experience in a mixed rural/urban setting, the main variables associated with survival, and the preliminary results of the implementation of an automated external defibrillator (AED) programme operated by lay volunteers on the effectiveness of the existing Emergency Medical Service (EMS). We report data from an observational cohort study on all adults, resuscitated from witnessed cardiac arrest between 1994 and 2004 in the district area of Forlì (Italy). The AED programme was introduced in 2002. Entry variables, time intervals and nodal events were tested according to Utstein recommendations. The predictors of favourable outcomes (Overall Performance Category 1-2) were identified by logistic regression analysis. The witnessed cardiac arrest rate was 27/100,000 population per year (95% confidence interval, 18-38). The initial rhythm was shockable in 241/479 cases (50.3%). After resuscitation, 55 (11.5%) subjects had a favourable outcome at discharge and 38 (7.9%) at 1 year. Time-to-treatment was longer for EMS than for AED-equipped units (median, 8 min interquartile range, 6-10 (467 cases) versus 6 min interquartile range, 4-8 (13 cases); P<0.013), but the final results of the AED programme were poor, with only 1 subject saved/171,000 inhabitants in 2 years. Positive outcome predictors were male sex, younger age, shockable rhythms, low number of defibrillations, and no history of hypertension, diabetes, myocardial infarction or congestive heart failure. Even in a mixed urban/rural setting, survival from out-of-hospital cardiac arrest is dependent on well-known predictors. In our setting, the number of cases saved by an AED programme is limited when accompanied by an efficient traditional EMS. The allocation of resources to an AED programme should be reconsidered in a mixed rural/urban setting.