Abstract 156: Which Factors Promote Transition From PEA to Spontaneous Circulation and PEA Recurrence in Children?

Abstract

Background: Pediatric cardiac arrests are relatively rare outside specialist centres, and may differ in several ways from adults. The aim of this study was to investigate factors that may impact on the transition from Pulseless electrical activity (PEA) to Return of spontaneous circulation (ROSC), or recurrence of PEA from ROSC, in children and adolescents. Methods: We prospectively registered resuscitation episodes in a pediatric hospital over a period of 3 years, using defibrillators that can register CPR variables like chest compression depth and rate, and ventilation rate. ROSC was defined as an organized electrical rhythm without chest compressions >= 1 minute. CPR variables, patient characteristics and etiology, and dynamic covariates (e.g. the proportion of time spent in PEA or ROSC) were entered as univariate predictors of the transition intensity between PEA and ROSC or the reverse. Statistical anlysis was done with using Aalen’s additive regression model, a variant of survival analysis. Results: In 64 cardiac arrest patients (median age 15, range 2-22 years), there were 49 transitions from PEA to ROSC, and 25 recurrences of PEA from ROSC. Identified factors favoring a transition from PEA to ROSC include greater mean compression depth (p=0.010), higher weight (p=0.006), and lower proportion of PEA for the last 5 minutes (p=0.001). PEA recurrence from ROSC was also associated with greater mean compression depth (p=0.006) and higher weight (p=0.021). However, respiratory etiology was negatively associated with PEA recurrence (p=0.007). Immediate effects (i.e. the last 1-minute average) were more pronounced than 3-minute average effects. Dynamic covariates, which capture the course of the individual patient (e.g. cumulative time in PEA or in ROSC, number of transitions), were strongly associated with the transitions. Conclusion: Some event variables (compression depth, patient weight) were associated with transitions between PEA and ROSC in both directions, and a respiratory etiology appears to protect against PEA recurrence. Dynamic covariates impact on the likelihood of transitioning from PEA to ROSC or PEA recurrence.