Time to Return of Spontaneous Circulation and Long-Term Outcomes in Bystander-Witnessed Out-of-Hospital Cardiac Arrest Survivors.

BACKGROUND AND AIMS: Immediate Out-of-hospital cardiac arrest (OHCA) survival is time-sensitive, however, evidence linking resuscitation time to recovery is limited. We examined time from emergency call to return of spontaneous circulation (time-to- ROSC) and survivor outcomes.

METHODS

From the Danish Cardiac Arrest Registry, we included adults with bystander-witnessed OHCA (2016-2023) surviving ≥30 days, without prior anoxic brain damage or nursing home admission. Time-to-event and multivariable regression analyses stratified by time-to-ROSC (A:0-10, B:11-18, C:>18 minutes) assessed 11- month anoxic brain damage and nursing home admission, plus long-term survival and return-to-work through December 2024.

RESULTS

We included 2,583 patients (n=875, 869, 839; groups A-C, respectively), 78% male; median age 65; median time-to-ROSC 14 min. Anoxic brain damage increased with time-to-ROSC (A-C: 0.3%, 1.8%, 3.2%; p<0.001). Adjusted analyses showed an overall association (p=0.03); HRs: 5.58 (95% CI 1.58-19.64) for B and 9.98 (95% CI 2.93-33.96) for C versus A. Nursing home admission decreased with time-to- ROSC (A-C: 3.1%, 2.2%, 1.3%; p=0.04), but adjustments attenuated the association (p=0.3). Long-term survival was similar (5-year Kaplan-Meier estimate: 79%; 95% CI 77-81%; p = 0.80; adjusted p = 0.99). Among employed patients (n=177, 168, 179), return-to-work was similar (5-year cumulative incidence: 60%; 95% CI 56-65%; p = 0.31; adjusted p = 0.29).

CONCLUSIONS

In bystander-witnessed 30-day OHCA survivors, prolonged resuscitation does not preclude recovery, time-to-ROSC was associated with anoxic brain damage but not nursing home admission, return-to-work, or long-term survival.