Incidence and percentage of survival after cardiac arrest outside and inside hospital: A comparison between two regions in Sweden.

Aim: To compare the incidence and percentage of survival after cardiac arrest outside and inside hospital where cardiopulmonary resuscitation (CPR) had been started between two regions in Sweden in a 10-year perspective.

Methods: A retrospective observational study including CPR treated patients both after out-of-hospital and in-hospital cardiac arrest (OHCA and IHCA) in Sweden, 2013-2022. Data was retrieved from the Swedish Registry of Cardiopulmonary Resuscitation (SRCR).

Results: The overall incidence of OHCA and IHCA events were 2,940 in Dalarna (having a lower population and population density) and 16,187 in Västra Götaland (having a higher population and population density). The overall incidence of survival when OHCA and IHCA were combined was 20 per 100,000 person years in Dalarna and 19 per 100,000 person years in Västra Götaland. The corresponding result for OHCA was 9 versus 7 and for IHCA 11 versus 12. The overall percentage of survival was 20% in Dalarna and 19% in Västra Götaland. The corresponding result for OHCA was 13% versus 10% and for IHCA 37% versus 36%.

Conclusion: Overall, there was no marked difference neither in incidence nor in percentage of survival after cardiac arrest between the two regions. However, regarding cardiac arrest that took place outside hospital both incidence and percentage of survival was higher in Dalarna than in Västra Götaland despite the fact that the former had lower population density.