Objective For out-of-hospital pediatric cardiac arrest (CA), guidelines have evolved such that AED application has supplanted CPR as the initial resuscitation strategy for children 1 year and older. The best approach to resuscitation, AED first versus CPR first, in a two-tiered emergency medical services (EMS) system depends in part on how likely the patient is to present with ventricular fibrillation. We evaluated the frequency of ventricular fibrillation with respect to age and other potential predictors among pediatric CA patients.
Methods The investigation was a cohort study of EMS-treated, non-traumatic out-of-hospital CA among persons 1–18 years in King County, WA between April 1, 1976 through December 31, 2003. We used multivariable logistic regression to determine characteristics independently associated with ventricular fibrillation.
Results Ventricular fibrillation was the presenting rhythm in 17.6% (48/272). The proportion presenting with ventricular fibrillation was 7.6% (10/131) among children age 1–7 years and 27.0% (38/141) among children 8–18 years (P≤0.001). In multivariable models, ventricular fibrillation was independently associated with age > 8 compared to 1–7 years (Odds ratio[OR]=3.19, 95% confidence interval [1.46–6.97]), witnessed arrest (OR=3.33 [1.63–6.82]), and cardiac etiology (OR=2.89 [1.32–6.34]). Survival was 31.3% (15/48) for ventricular fibrillation and 10.7% (24/224) for non-shockable rhythm CAs.
Conclusion Based on these results, the best approach for initial EMS resuscitation in a two-tiered EMS system, CPR first versus AED first, is uncertain among younger children. Inclusion of witnessed cardiac arrest status into the decision process for younger children potentially could more efficiently allocate the AED versus CPR approach.