Recent trends in out-of-hospital cardiac arrest (OHCA) outcomes in Singapore in the era of covid-19

ABSTRACT

Objectives: To analyse the incidence of emergency medical serviceattended out-of-hospital cardiac arrests (OHCAs) and prehospital return of spontaneous circulation (ROSC) outcomes in Singapore from January to May 2020, as compared to the same period in 2018 and 2019. Methods: This was a retrospective observational study comparing current and previous emergency medical service (EMS) data and OHCA records maintained by the Singapore Civil Defence Force (SCDF). These figures were tabulated from data input by experienced paramedics responding to EMS calls and verified by an internal audit team. The study was conducted in accordance with the STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) guidelines, and examined factors that may have contributed to an increase or decrease in OHCA incidence and prehospital ROSC attainments during the different time periods. Results: Coronavirus Disease 2019 (COVID-19) is a global pandemic of unparalleled scale. Despite total EMS call volumes and overall OHCA incidence remaining comparable to pre-COVID periods, there was a concerning decrease in pre-hospital ROSC attainments between January to May 2020 (an average of 8.4%). Based on multivariable logistic regression, this was much lower when compared to previous years, where the pre-hospital ROSC rates remained around 12% (p<0.001). Further analyses did not reveal significant differences in terms of the median age of OHCA victims, the percentage of shockable rhythm or response times. However, it was noted that more OHCAs were occurring in residential homes, while those in public spaces decreased considerably compared to previous years (p<0.001). In addition, there was also a drop in the overall bystander cardiopulmonary resuscitation (CPR) rates compared to pre-COVID periods (p<0.001). Conclusion: The findings remain preliminary and follow-up data in the subsequent months are necessary to further investigate these trends. Nonetheless, they provide important lessons for public education and pandemic preparedness. To strengthen the first links in the survival chain, members of the public should be educated to initiate CPR and automated external defibrillator (AED) for any non-responsive victim (even without mouth-to-mouth ventilation).