Abstract 229: What is the Real Incidence of Out-Of-Hospital Cardiac Arrest in Norway

Abstract

Purpose of the study: The Norwegian Cardiac Arrest Registry (NorCAR) is a mandatory national registry of resuscitation attempts that monitors the population incidence, care and outcome for cardiac arrest. Previously, substantial differences in the number of included patients per 100 000 inhabitants were observed in some “atypical” health trusts (HT). It was not known if this is a problem with data collection or reflected genuine population differences. The purpose of this study was to identify all patients that fill NorCAR’s inclusion criteria among these HTs, by imposing consistent methods for data collection. Materials and methods: The registry implemented consistent, standardised and rigorous data collection methods including targeted audits in four “atypical” health trusts, two with a high and two with a low reported population incidence. Registrations from January to March 2019 was compared with similar results from 2018. Results: In 2018, the observed nationwide annual incidence of out-of-hospital cardiac arrest was 64 per 100 000 inhabitants, varying from 40 to 102. At the four study sites the observed population incidence was stable among HT with high incidence (88 and 110) but apparently increased in the two HTs with previous low incidence after implementation of standardised collection method (from 48 to 56, and 46 to 54). Conclusions: The previously “atypical” low incidence probably reflected a problem with data collection. To achieve full coverage of the population, all data collectors need to collect data using the same method with a concise and thorough investigation of ambulance-, air ambulance-, dispatch-, and hospital records. Data collectors need to have a close relationship with ambulance and dispatch, and constant reminders and feedback on reported results are important. Implementing a new method for data collection takes time, and results need to be evaluated over time.