The short- and mid-term mortality trends in out-of-hospital cardiac arrest survivors: insights from a 5-year multicenter retrospective study in Taiwan.

Background: The survival trend and factors influencing short- and mid-term mortality in Asian out-of-hospital cardiac arrest (OHCA) survivors should be elucidated. We performed survival analyses on days 3 and 30, hypothesizing decreased survival rates within the initial 3 days post-resuscitation. Additionally, variables linked to mortality at these two timepoints were examined. Methods: We performed a retrospective analysis on adult nontraumatic OHCA survivors admitted to the National Taiwan University Hospital and its branches between 2017 and 2021. We collected the following variables from the NTUH-Integrative Medical Database: basic characteristics, cardiopulmonary resuscitation events, inotrope administration, and post-resuscitation management. The outcomes included 3- and 30-day mortality. Subgroup analyses with the Kaplan-Meier method explored the survival probability of the OHCA survivors and assessed differences in cumulative survival among subgroups. Cox proportional hazards model was used to estimate adjusted hazard ratios with 95% confidence interval. Results: Of the 967 survivors, 273 (28.2%) and 604 (62.5%) died within 3 and 30 days, respectively. The 30-day survival curve after OHCA showed an uneven decline, with the most significant decrease within the first 3 days of admission. Various risk factors influence mortality at 3- and 30-day intervals. Although increased age, noncardiac etiology, and prolonged low-flow time increased mortality risks, bystander CPR, targeted temperature management, and continuous renal replacement therapy were associated with reduced mortality at 3- and 30-day timeframes. Conclusion: Survival declined in most OHCA survivors within 3 days post-resuscitation. The risk factors associated with mortality at 3- and 30-day intervals varied in this population.