BACKGROUND: Survival after in-hospital cardiac arrest (CA) has been reported to be surprisingly low without any major improvement during the last decade. AIMS: The aim of this study is to evaluate the clinical impact (delay to defibrillation and survival after CA) of an intervention within 1 single hospital (Västerås, Sweden), including (1) a systematic education of all health care professionals in cardiopulmonary resuscitation and (2) the implementation of 18 automated external defibrillators. METHODS: Information was retrieved from the Swedish National Register of Cardiopulmonary Resuscitation. The differences between the 2 calendar periods were evaluated by χ(2) and Fisher exact tests. Logistic regression was used to control for potential confounders. RESULTS: In total, there were 73 in-hospital CAs before (12 months) and 133 after (18 months) the intervention. The overall delay to defibrillation was not reduced after the intervention, and the proportion of survivors to hospital discharge was 26% before and 32% after the intervention (P =.51). Cerebral function, however, was improved after the intervention (as judged by the cerebral performance categories score; P < .001). Thus, the proportion of survivors among all CA patients discharged with a cerebral performance scale score of 1 or 2 (good or acceptable cerebral function) increased from 20% to 32%. CONCLUSION: An intervention within 1 single hospital (systematic training of all health care professionals in cardiopulmonary resuscitation and implementation of automated external defibrillators) did not reduce treatment delay or increase overall survival. Our results, however, suggest indirect signs of an improved cerebral function among survivors.