INTRODUCTION: Out-of-hospital cardiac arrests increased during the COVID-19 pandemic and a direct mechanism of cardiac arrest in infected patients was hypothesized. Therefore, we conducted a systematic review and meta-analysis to assess outcomes of SARS-CoV-2 patients with out-of-hospital cardiac arrest. METHODS: PubMed and EMBASE were searched up to April 05, 2021. We included studies comparing out-of-hospital cardiac arrests patients with suspected or confirmed SARS-CoV-2 infection versus noninfected patients. The primary outcome was survival at hospital discharge or at 30 days. Secondary outcomes included return of spontaneous circulation, cardiac arrest witnessed and occurring at home, bystander-initiated cardiopulmonary resuscitation, proportion of nonshockable rhythm and resuscitation attempted, and ambulance arrival time. RESULTS: In the ten included studies, 18% (1341/7545) of out-of-hospital cardiac arrests occurred in patients with SARS-CoV-2 infection. Patients with out-of-hospital cardiac arrest and SARS-CoV-2 infection had reduced rates of survival (16/856 [1.9%] vs. 153/2344 [6.5%]; odds ratio (OR) = 0.33; 95% confidence interval (CI), 0.17–0.65; P = 0.001; I(2) = 28%) and return of spontaneous circulation (188/861 [22%] vs. 640/2403 [27%]; OR = 0.75; 95% CI, 0.65–0.86; P < 0.001; I(2) = 0%) when compared to noninfected patients. Ambulance arrived later (15 ± 10 vs. 13 ± 7.5 min; mean difference = 1.64; 95% CI, 0.41–2.88; P = 0.009; I(2) = 61%) and nonshockable rhythms (744/803 [93%] vs. 1828/2217 [82%]; OR = 2.79; 95% CI, 2.08–3.73; P < 0.001; I(2) = 0%) occurred more frequently. SARS-CoV-2 positive patients suffered a cardiac arrest at home more frequently (1186/1263 [94%] vs. 3598/4055 [89%]; OR = 1.86; 95% CI, 1.45–2.40; P<0.001; I(2) = 0%) but witnessed rate (486/890 [55%] vs. 1385/2475 [56%]; OR = 0.97; 95% CI, 0.82–1.14; P = 0.63; I(2) = 0%) and bystander-initiated cardiopulmonary resuscitation rate (439/828 [53%] vs. 1164/2304 [51%]; OR = 0.95; 95% CI, 0.73–1.24; P = 0.70; I(2) = 53%) were similar. CONCLUSIONS: One-fifth of out-of-hospital cardiac arrest patients had SARS-CoV-2 infection. These patients had low rates of return of spontaneous circulation and survival and were characterized by higher nonshockable rhythms but similar bystander-initiated cardiopulmonary resuscitation rate. REVIEW REGISTRATION: PROSPERO - CRD42021243540.
Outcomes of out-of-hospital cardiac arrest in patients with SARS-CoV-2 infection: a systematic review and meta-analysis