Abstract 16: Subsequent VF is Associated with Better Outcomes from Out-of-Hospital Cardiac Arrests with Initial Non-shockable Rhythms~population-based Utstein Study In Japan~
OBJECTIVE: To compare survival rates from out-of-hospital cardiac arrest (OHCA) with an initial non-shockable rhythms according to whether they remained in a non-shockable rhythm or converted to shockable rhythms.
METHODS: Designs: Population-based cohort study. Subjects: Witnessed OHCA cases of cardiac etiology with pulseless electrical activity (PEA) or asystole as initially recorded rhythm. Main outcome measure: Neurologically favorable one-month survival. We enrolled all adult (age ≥ 18 years) patients with witnessed OHCA of cardiac etiology who were treated by the emergency medical services (EMS) in Osaka, Japan, from January 1 to December 31, 2005, by means of the Utstein Style. Resuscitation was performed according to the AHA guideline 2000. Survival indicators were compared between patients with sustained non-shockable rhythm (No-shock group) and patients with subsequent VF/VT and electrical shock (Shock group) using logistic regression.
RESULTS: Of 3191 OHCA of cardiac etiology, 824 witnessed cases had PEA or asystole as initially recorded rhythm. Of the 824, 742 (90%) remained in a non-shockable rhythm at each evaluation throughout the resuscitation while 82 (10%) subsequently converted to VF/VT and were shocked by EMS personnel. Neurologically favorable one-month survival was significantly greater in the Shock group (4.9% versus 0.8%, p=0.001). Subsequent VF/VT was a significant predictor (OR, 5.4; 95%CI, 1.38–20.9) of neurologically favorable survival after adjustment for potential confounders.
CONCLUSIONS: Among these patients with OHCA and initial non-hockable rhythm, subsequent VF/VT was associated with better outcomes.