Emergency medical system response time does not affect incidence of return of spontaneous circulation after prehospital resuscitation in one million central European agglomeration residents

Abstract

Background: The survival of out-of-hospital sudden cardiac arrest (OHSCA) in Europe still remains low. The State Medical Rescue System is composed of several elements. The efficacy of each of these elements may have an influence on the victim’s survival. Until now, the incidence of return of spontaneous circulation (ROSC) and its correlation with rescue services time in the city of Poznan has not been determined.

Aim: The main purpose of this study was to assess incidents of OHSCA and prehospital frequency of ROSC after OHSCA in Poznan city and district. We also wanted to analyse whether ROSC depends on Emergency Medical System (EMS) reaction time.

Methods: Retrospective analysis based on medical documentation conducted in 2015 in Poznan EMS.

Results: Return of spontaneous circulation was achieved in 68.88% of cases. It was most frequent when OHSCA occurred in public places (p = 0.000, contingency factor = 0.233) and victims were younger (p = 0.042, contingency factor = 0.129). 63.17% of patients were male, but sex did not affect the incidence of ROSC. The median time of system response was 8.53 min, while time from ambulance departure to arrival was 5.42 min. We did not find any statistically significant difference between the number of deaths and those parameters (p = 0.723, p = 0.891). However, longer team response time correlated with the highest mortality (p = 0.042, contingency factor = 0.126). In the group where ROSC was achieved the median time of EMS response was 8.18 min, while among the group of deceased the median was 8.63 min.

Conclusions: The incidence of OHSCA in our region is similar to other Polish and European cities. EMS response time does not affect the frequency of ROSC. ROSC was achieved more often if OHSCA occurred in public and the victim was younger.