Abstract P179: Effectiveness of CPR Prior to Electrical Shock to Out-of-hospital Cardiac Arrest with Ventricular Fibrillation: A Population-based Study in a Metropolitan Area in Japan “The Utstein Osaka Project”
Objective: To evaluate the effectiveness of CPR prior to electrical shock stratified by the duration from ambulance call to CPR in witnessed out-of-hospital cardiac arrest patients with VF.
Study Design: Population-based observational study (May 1, 1998–December 31, 2006).
Settings: Osaka, Japan with a population of 8.8 million.
Subjects: We analyzed the Utstein Style data on patients who met the following inclusion criteria:
witnessed by citizens,
18 years or older,
initial recorded cardiac rhythm was VF or pulseless VT,
bystander CPR was not performed.
Methods: Subjects were divided into three groups according to the duration from the initiation of CPR by ambulance personnel to first electrical shock; immediate shock group: first electrical shock were given in 0–1 minute after CPR was initiated; 2–3 min delayed group: first electrical shock were given in 2–3 minutes after CPR initiated; and ≥4 min delayed group: first electrical shock were given in more than 4 minutes.
Main outcome measure: Survival at one month.
Results: 909 patients were included in the current analysis. In immediate shock group, survival at one month decreased with an increase in interval between ambulance call and the initiation of CPR. In contrast, 2–3 min delayed group had better prognosis than immediate shock group if CPR was initiated between 8–9 minutes after ambulance call (13% vs. 27% of one month survival; OR 2.50; 95% CI. 1.02–6.00; P=0.045).
Conclusion: Our findings suggested that 2–3 minute-delayed electrical shock was associated with better prognosis compared with immediate electrical shock if CPR by ambulance personnel was initiated in 8–9 minutes from ambulance call.