This retrospective cohort study used the All-Japan Utstein Registry (2005–2023) to compare outcomes in adult witnessed suffocation-related OHCA by bystander CPR type: chest-compression-only (CC-CPR), chest-compression-plus-ventilation (CCV-CPR), or no CPR, with CC-CPR as the reference. The primary outcome was favorable neurological status at one month.
Among 76,774 patients, neither CCV-CPR nor CC-CPR outperformed no CPR. After IPTW adjustment, no CPR was associated with *higher* odds of favorable neurological outcome (aOR 1.20, 95% CI 1.04–1.38) and one-month survival (aOR 1.20, 95% CI 1.12–1.28) vs. CC-CPR; CCV-CPR showed no significant difference for either outcome. No differences were seen for ROSC.
- Observational registry design precludes causal inference; unmeasured confounders (e.g., exact airway obstruction type, time to obstruction relief) cannot be excluded. - CCV-CPR group was small (n=8,182 vs. ~40k CC-CPR), and CPR quality was not captured. - No CPR group may include cases where EMS arrived rapidly, biasing survival estimates upward.
These data challenge the assumption that adding rescue breaths improves outcomes in suffocation-related OHCA—bystander CPR type alone does not appear to drive neurological recovery. Clinicians and dispatchers should recognize that airway clearance and other prehospital factors may matter more than ventilation technique in this specific arrest etiology.
