Acute cardiac care & resuscitationCohort study
Association Between Delay to First Shock and Successful First-Shock Ventricular Fibrillation Termination in Patients With Witnessed Out-of-Hospital Cardiac Arrest
- Prospective registry cohort study
- ARREST registry
- Poisson regression with robust standard errors
Authors' conclusion
Every minute of delay to first shock was associated with a significantly lower proportion of VF termination and return of organized rhythm.
Study context
- Population
- Patients with witnessed OHCA and ventricular fibrillation (VF) as initial rhythm (ARREST registry, Amsterdam)
- Participants
- 3,723 patients
- Exposure
- Longer vs shorter delay from emergency call to first shock
- Outcome
- VF termination at 5 seconds after the first shock, return of organized rhythm and survival to discharge, in relation to delay to first shock
Main finding
VF termination by delay to first shock · 5 seconds after first shock
Adjusted relative risk
1.06
95% CI 1.04–1.07
Per additional minute in VF from emergency call
adjusted RR 1.06 (95% CI 1.04–1.07)
Per additional minute in VF from emergency call, as printed
As reported in the abstract
- VF termination with delay to first shock <6 minutes
- 93%
- VF termination with delay to first shock >16 minutes
- 75%
- Trend in VF termination across delay
- P for trend < 0.001
Observational data: associations, not effects.
Further findings
| Outcome | adjusted RR (95% CI) | |
|---|---|---|
| Return of organized rhythm | 0.96 (0.95–0.98) | |
| Survival to discharge | 0.94 (0.93–0.95) | |
| 0.512Adjusted relative risk (log scale) |
Original publication
Association Between Delay to First Shock and Successful First-Shock Ventricular Fibrillation Termination in Patients With Witnessed Out-of-Hospital Cardiac Arrest. Circulation. Published 27 October 2024. doi:10.1161/circulationaha.124.069834
Summarised from the published abstract; every number is checked against it