RESUMO
BACKGROUND: The aim of this study was to examine the impact of COVID-19 on the response rate of community-first-responders (CFR) and other out-of-hospital-cardiac-arrest (OHCA) outcomes using the smartphone-first-responder-system (SFRS) "Mobile Retter." METHODS: All adult non-traumatic OHCA in the district of Gütersloh between 01.01.2018-31.12.2021 were included. Periods of interest were 1) prior to the first COVID-19-lockdown; to 2) both lockdowns; and 3) the time in between, as well as after the COVID-19-lockdowns (pre-COVID-19, COVID-19-lockdown and COVID-19-pandemic respectively). The primary outcome was the CFR response rate defined as proportion of CFR alerts that were accepted by a CFR and in which at least one CFR arrived on scene of the emergency out of all CFR alerts. Secondary outcomes included the rate of CFR alerts, defined as proportion of OHCA to which CFR were summoned by the emergency medical dispatcher, as well as the rate of return-of-spontaneous-circulation (ROSC) and rate of survival until hospital discharge. We also examined the incidence COVID-19-infection of CFR in context of the SFRS. RESULTS: A total of 1064 OHCA-patients (mean age: 71.4±14.5 years; female: 33.8%) were included in the study (Pre-COVID-19: 539; COVID-19-lockdown: 109; COVID-19-pandemic: 416). The response rate was 64.0% (pre-COVID-19: 58.7%; COVID-19-lockdown: 63.5%; COVID-19-pandemic: 71.8%, P=0.002 vs. pre-COVID-19). The alert rate was 52.7% (pre-COVID-19: 56.2%; COVID-19-lockdown: 47.7%, P=0.04 vs. Pre-COVID-19; COVID-19-Pandemic: 49.5%, P=0.02 vs. pre-COVID-19). The ROSC-rate was 40.4% (pre-COVID-19: 41.0%; COVID-19-lockdown: 33.9%; COVID-19-pandemic: 41.4%) and hospital discharge rate 31.2% (Pre-COVID-19: 33.0%; COVID-19-lockdown: 36.8%; COVID-19-pandemic: 28.7%). The use of CFR was associated with favorable effects in terms of hospital admission (odds ratio [OR]: 0.654 (CI95: 0.444-0.963), P=0.03), hospital discharge (OR: 2.343 (CI95: 1.002-5.475), P=0.04). None of the CFR became infected with COVID-19. CONCLUSIONS: "Mobile-Retter" was associated with high response rates, improved outcome in OHCA patients and no COVID-19-infections of CFR during the COVID-19-pandemic and -lockdowns.