Rationale: Nearly 3 in 5 in-hospital cardiac arrests (IHCAs) occur in the intensive care unit (ICU), yet large-scale data on the outcomes of in-ICU cardiac arrests have not been published for over a decade. Objectives: We sought to examine outcomes of in-ICU cardiac arrests, evaluating both achievement of return of spontaneous circulation (ROSC) and subsequent survival to hospital discharge and how these have changed over time and by type of cardiac arrest. Methods: This was an observational study using the Get With The Guidelines-Resuscitation registry, an American Heart Association-sponsored, prospective, multisite registry of IHCAs in the United States, including adults 18 years of age and older with a confirmed initial cardiac arrest occurring in the ICU who underwent resuscitation. Outcomes included achievement of ROSC and survival to hospital discharge. Multivariable hierarchical logistic regression adjusting for patient-level factors and hospitals as random effects was used to evaluate ROSC and survival. Results: A total of 114,371 adult, in-ICU IHCAs from January 2006 to December 2018 were studied. The mean age was 63.8 years, 41.3% were women, and 82.1% had a nonshockable initial rhythm. Of the 114,371 ICU cardiac arrests, 70,610 (61.7%) achieved ROSC, and 21,747 (19.0%) survived until hospital discharge. The rate of ROSC improved from 2006 to 2018 (unadjusted rate, 55.0-65.4%; adjusted odds ratio [OR] per year, 1.04; 95% confidence interval [CI], 1.03-1.05). There was an increase in overall survival to discharge during this time (unadjusted rate, 16.7-20.5%; adjusted OR per year, 1.03; 95% CI, 1.03-1.04). The survival to discharge rate of the 70,610 patients who achieved ROSC increased slightly (unadjusted rate, 30.3-31.4%; adjusted OR per year, 1.02; 95% CI, 1.01, 1.02). Conclusions: There is an increase in survival to discharge for patients who experienced a cardiac arrest in the ICU between 2006 and 2018. There is an increase in achievement of ROSC and post-ROSC survival to discharge, although the increase in achievement of ROSC was greater than the increase in post-ROSC survival.
Keywords: ICU; cardiac arrest; return of spontaneous circulation; survival to discharge.