Association between the timing of prehospital epinephrine administration and patient outcomes after out-of-hospital cardiac arrest in Korea: a nationwide observational study.

Among 10 726 patients, 3589 (33.5%) received epinephrine within 20 min.

In continuous models, each 1-minute delay was associated with lower odds of good Cerebral Performance Category (aOR 0.964, 95% CI 0.942 to 0.987); a 5-minute delay corresponded to aOR 0.833 (95% CI 0.741 to 0.937) and bin-wise estimates showed a marked drop beyond 30 min (aOR 0.048, 95% CI 0.006 to 0.393).