ABSTRACT: IMPORTANCE:Delay in administration of the first epinephrine dose is associated with decreased survival among adults after in-hospital, nonshockable cardiac arrest. Whether this association is true in the pediatric in-hospital cardiac arrest population remains unknown. OBJECTIVE:To determine whether time to first epinephrine dose is associated with outcomes in pediatric in-hospital cardiac arrest. DESIGN, SETTING AND PARTICIPANTS:We performed an analysis of data from the Get With the Guidelines-Resuscitation registry. We included US pediatric patients (age <18 years) with an in-hospital cardiac arrest and an initial nonshockable rhythm who received at least 1 dose of epinephrine. A total of 1558 patients (median age, 9 months [interquartile range [IQR], 13 days-5 years]) were included in the final cohort. EXPOSURE:Time to epinephrine, defined as time in minutes from recognition of loss of pulse to the first dose of epinephrine. MAIN OUTCOMES AND MEASURES:The primary outcome was survival to hospital discharge. Secondary outcomes included return of spontaneous circulation (ROSC), survival at 24 hours, and neurological outcome. A favorable neurological outcome was defined as a score of 1 to 2 on the Pediatric Cerebral Performance Category scale. RESULTS:Among the 1558 patients, 487 (31.3%) survived to hospital discharge. The median time to first epinephrine dose was 1 minute (IQR, 0-4; range, 0-20; mean [SD], 2.6 [3.4] minutes). Longer time to epinephrine administration was associated with lower risk of survival to discharge in multivariable analysis (multivariable-adjusted risk ratio [RR] per minute delay, 0.95 [95% CI, 0.93-0.98]). Longer time to epinephrine administration was also associated with decreased risk of ROSC (multivariable-adjusted RR per minute delay, 0.97 [95% CI, 0.96-0.99]), decreased risk of survival at 24 hours (multivariable-adjusted RR per minute delay, 0.97 [95% CI, 0.95-0.99]), and decreased risk of survival with favorable neurological outcome (multivariable-adjusted RR per minute delay, 0.95 [95% CI, 0.91-0.99]). Patients with time to epinephrine administration of longer than 5 minutes (233/1558) compared with those with time to epinephrine of 5 minutes or less (1325/1558) had lower risk of in-hospital survival to discharge (21.0% [49/233] vs 33.1% [438/1325]; multivariable-adjusted RR, 0.75 [95% CI, 0.60-0.93]; P?=?.01). CONCLUSIONS AND RELEVANCE:Among children with in-hospital cardiac arrest with an initial nonshockable rhythm who received epinephrine, delay in administration of epinephrine was associated with decreased chance of survival to hospital discharge, ROSC, 24-hour survival, and survival to hospital discharge with a favorable neurological outcome.