Intraosseous route is associated with prolonged epinephrine-to-ROSC interval in out-of-hospital cardiac arrest.

Background: Prolonged resuscitation is associated with poor patient outcomes. While the importance of bystander CPR and early defibrillation is well-known, the role of other components affecting resuscitation duration is less well-established. We postulated that first-dose intraosseous (IO) epinephrine would prolong the pressor-to-ROSC interval compared to intravenous (IV) drug administration.

Aims: To describe the relationship between first epinephrine administration route and pressor-to-ROSC intervals.

Methods: A retrospective analysis of the 2020 ESO Data Collaborative Annual Research dataset was conducted among adults who experienced non-traumatic, bystander-witnessed arrests. A Cox proportional hazard model was used to determine the influence of first epinephrine route on the pressor-to-ROSC interval. End-of-event was defined as ROSC, field termination of resuscitation, or hospital arrival without ROSC, with right censoring of the latter group.

Results: Overall, 9351 patients were included for analysis, of which 63.9% were males. The mean age of participants was 65.3(± 15.5) years and presumed cardiac etiology was present in 82.7% of arrests. An initial shockable rhythm was present in 27.1%, while 29.7% received bystander CPR and 39.7% attained ROSC. The mean pressor-to-ROSC interval was 13.21(± 9.65), 14.86 (± 10.89), and 14.42 (± 10.52) minutes for the intravenous, tibial IO, and humeral IO routes, respectively (p < 0.001). First epinephrine administration via the tibial or humeral IO route was associated with a decreased hazard of ROSC compared to the IV route (HR = 0.78, p < 0.001 and HR = 0.86, p = 0.01 per minute, respectively).

Conclusions: These data suggest that the tibial and humeral IO routes of first epinephrine administration were associated with marginally prolonged resuscitation duration after drug administration and decreasing hazard of ROSC.