Abstract 78: 30:2 vs 15:2 Compression-Ventilation Ratio by Emergency Medical Services Responders in Patients with Out-of-Hospital Nonshockable Cardiac Arrest
BACKGROUND The 2010 AHA guidelines for CPR recommended that emergency medical services (EMS) responders should use minimal interruptions in chest compressions using a 30:2 compression-ventilation ratio in adult victims. However, it is unclear whether this CPR by EMS responders can improve survival for adults with non-shockable cardiac arrest (CA) including pulseless electrical arrest (PEA) and asystole.
METHODS We compared the effects of a 30:2 compression-ventilation ratio CPR by EMS responders recommended in the 2005 CPR guidelines with those of a 15:2 compression-ventilation ratio CPR recommended in the 2000 CPR guidelines from the data of the All-Japan Utstein Registry, a prospective, nationwide, observational registry. The study endpoints were return of spontaneous circulation (ROSC) on hospital arrival and 30-day favorable neurological outcome after CA.
RESULTS Of the 58,448 adult patients with bystander-witnessed out-of-hospital CA due to presumed cardiac etiology in the year 2005, 2008 and 2009, 24,250 with non-shockable cardiac arrest who did not receive bystander CPR were included; 16,091 received a 30:2 CPR by EMS responders, and 8,159 received a 15:2 CPR by EMS responders. The 30:2 group had significantly higher rates of ROSC and favorable neurological outcome than the 15:2 group in the whole cohort (ROSC; 6.6% vs. 4.2%, p<0.001, favorable neurological outcome; 1.3% vs. 0.8%, p<0.001), and in the subgroups of patients with PEA (ROSC; 9.8% vs. 5.8%, p<0.001, favorable neurological outcome; 2.4% vs. 1.6%, p=0.002). Although the 30:2 group had a significantly higher ROSC rate than the 15:2 group (4.3% vs. 3.3%, p=0.002), favorable neurological outcome did not differ between the 30:2 group and the 15:2 group (0.5% vs. 0.3%, p=0.28) in the subgroups of patients with asystole. The adjusted odds ratios after a 30:2 CPR was 1.62 (95% CI, 1.43-1.84) for ROSC and 1.56 (95% CI, 1.18-2.05) for favorable neurological outcome, and other independent predictor of each study endpoint was PEA.
CONCLUSION A 30:2 compression-ventilation ratio CPR by EMS responders improved ROSC and favorable neurological outcome in adult patients with bystander-witnessed out-of-hospital PEA CA, but this CPR had not neurological benefits for adult patients with asystole CA.
- © 2011 by American Heart Association, Inc.