No-flow duration and outcomes in adult blunt traumatic out-of-hospital cardiac arrest.
The American journal of emergency medicine · 2026-07-30 · Registry study
Abstract
OBJECTIVE: Out-of-hospital cardiac arrest (OHCA) due to blunt trauma has extremely poor outcomes and may have a shorter tolerable no-flow duration than nontraumatic OHCA. This study aimed to characterize the association between no-flow duration and prognosis in adults with witnessed blunt traumatic OHCA using dynamic probability curves. METHODS: This nationwide, population-based, retrospective cohort study used the All-Japan Utstein Registry from January 1, 2010, through December 31, 2023. Adults with witnessed OHCA due to blunt trauma were included. No-flow time was defined as the interval from witnessed cardiac arrest to initiation of CPR by emergency medical services personnel. The primary outcome was 30-day favorable neurological outcome (Cerebral Performance Category 1 or 2), and the secondary outcome was 30-day survival. Dynamic probability curves with pointwise 95% confidence intervals (CIs) were estimated using the exact Clopper-Pearson method, and no-flow thresholds below 1% were estimated with bootstrap 95% CIs. RESULTS: Among 1,795,502 registry patients, 14,334 met the eligibility criteria. Median age was 66 years, 9451 patients (65.9%) were male, and median no-flow time was 10 min. Thirty-day favorable neurological outcome occurred in 73 patients (0.5%), and 264 patients (1.8%) survived to 30 days. The no-flow thresholds below 1% with 95% CIs were 0 (0-0) minutes for 30-day favorable neurological outcome and 6 (4-8) minutes for 30-day survival. CONCLUSIONS: Adults with witnessed OHCA due to blunt trauma, the no-flow duration compatible with a chance of 30-day favorable neurological outcome was extremely short, and overall prognosis was poor.