Written by Jason Lesnick
This nationwide database study found that defibrillation within 2 minutes of starting CPR was associated with increased 1-month survival in out-of-hospital cardiac arrest (OHCA) patients.
Shock sooner, spark survival
These authors asked: Is defibrillation within 2 minutes of starting CPR associated with 1-month survival in patients who suffered atraumatic, shockable OHCA?
This nationwide (Japan, 2010–2019), retrospective, observational cohort study used registry data of 33,940 propensity-score analysis matched patients with initial shockable rhythm who received EMS defibrillation immediately (defined as < 2 minutes) or after ≥ 2 min of CPR.
The primary outcome was higher 1-month survival, while ROSC and good neurologic outcome (defined as cerebral performance category 1 or 2) were secondary outcomes. Immediate defibrillation was associated with: higher 1-month survival, 32.5% vs 29.1%, adjusted OR 1.18 (95%CI 1.12–1.24); ROSC 34.0% vs 29.8%, aOR 1.21 (95%CI 1.16–1.27); and good neurologic outcome, 22.6% vs. 18.9%; aOR 1.27 (1.20–1.34).
This paper outlines how Japan’s EMS system works to provide context for data interpretation, and it is relatively similar to ours in the U.S. (their ambulances have 3 EMTs and do not carry physicians as some European countries do).
How will this change my practice?
This paper strongly emphasizes the importance of time to defibrillation in our OHCA patients. Start CPR while attempting to analyze the patient’s rhythm as soon as possible in OHCA. If a shockable rhythm is identified, shock as soon as possible. Pro tip––charge the defibrillator before the rhythm check to save some time!
Source
Association Between Immediate Defibrillation and Outcomes in Shockable Out-of-Hospital Cardiac Arrest: A Propensity Score Analysis. Prehosp Emerg Care. 2025 Sep 30:1-8. doi: 10.1080/10903127.2025.2558868. Epub ahead of print. PMID: 40932764.
