Abstract Sat703: Challenging Convention Regarding Pediatric Non-Shockable Rhythms: Pulseless Electrical Activity and Asystole as Distinct Initial Rhythms

Background: Asystole and PEA occur as the initial rhythm in ~85% of pediatric IHCA yet are grouped together as “non-shockable” rhythms in resuscitation research and practice. Aim: To utilize the American Heart Association (AHA) Get with The Guidelines â -Resuscitation (GWTG Ò -R) registry to identify differences in patient and resuscitation characteristics, outcomes and trends over time between pediatric patients suffering IHCA with an initial rhythm of PEA or asystole. Hypothesis: PEA and asystole are distinct initial IHCA rhythms with distinguishing features and outcomes. Methods: Observational cohort study using the prospectively collected GWTG Ò -R registry. Pediatric patients (< 18 years) with an index IHCA and initial rhythm of PEA or asystole between 2000-2023 were included. Logistic regression adjusted a priori for covariates comparing patients with PEA vs. asystole with respect to pre-arrest characteristics, resuscitation practice, and outcomes. Outcomes included return of spontaneous circulation (ROSC) and survival to hospital discharge (SHD). Results: We identified 9,423 pediatric patients with non-shockable rhythms, of which 5,416 (57.5%) had an initial rhythm of PEA and 4,007 (42.5%) asystole. PEA arrests occurred in a lower proportion of neonates (26.6% vs 3.6%, p < 0.0001) with mean age 6.67 days (SD=11.06) in PEA arrests vs 5.20 days (SD=9.72) in asystole arrests (P = 0.0043), more commonly in patients with an illness category surgical-cardiac (20.3% vs 12.5%, p < 0.0001) and in an ICU than asystole (70.3% vs 60.2%, p < 0.0001). The observed and adjusted trend of the outcomes for ROSC and SHD is depicted in Figure 1 (observed) and Figure 2 (adjusted) for both PEA and asystole arrests over time. After controlling for covariates, patients with asystole had lower adjusted odds of ROSC (aOR): 0.70, 95%CI 0.64–0.77 (3,656 [67.5%] PEA vs 2,168 [54.1%] asystole) and lower aOR of SHD: 0.89, 95%CI 0.81-0.99 (1,875 [34.6%] PEA vs 1,193 [29.8%] asystole). Conclusion: Pediatric patients suffering IHCA with an initial rhythm of PEA had significant differences in patient characteristics, resuscitation factors, and outcomes compared to those with asystole. PEA was associated with higher rates of ROSC and SHD, whereas asystole was more frequently observed in less-monitored settings and carried a poorer prognosis. The persistence of these differences even after adjustment underscores the need for future research to refine rhythm-specific resuscitation strategies.