O2106: Should we follow neonatal resuscitation protocol or pediatric advanced life support in the first few days of life in neonates?

Background: A newborn requiring resuscitation in the hospital or brought from home to the ER may receive cardiopulmonary resuscitation (CPR) as per neonatal resuscitation guidelines (NRP) or pediatric advanced life support (PALS) guidelines. Other than data from the piglet model (Morin et al. 2024), no studies have assessed the effects of NRP vs. PALS on immediate outcomes in a transitioning asphyxia model.

Methods: We aimed to evaluate the effects of CPR based on NRP vs. PALS in a term asphyxiated cardiac arrest model, focusing on 1) incidence and time to return of spontaneous circulation (ROSC), and 2) hemodynamics and gas exchange. After IACUC approval, near-term lambs (139-141d gestation) were instrumented to measure hemodynamics (carotid, pulmonary, and coronary blood flows) and gas exchange. Fig. 1a illustrates the NRP and PALS protocol algorithms. The carotid and pulmonary flow snapshot highlights differences in chest compressions (CC) and positive pressure ventilation (PPV), with a 3:1 ratio in NRP vs. continuous CC and PPV in PALS, with pauses every 2 minutes to check the rhythm. To minimize bias, epinephrine (EPI) was administered intravenously at 0.03 mg/kg/dose every 3 minutes until ROSC (HR ≥ 100 bpm and diastolic BP ≥ 20 mmHg), with 100% oxygen used during CC in both groups. Data was analyzed using chi-square, unpaired t-test, and ANOVA.

Results: Characteristics of the lambs are shown in Table 1. 4/6 lambs (66.7%) in NRP group vs 1/6 (16%) in PALS group achieved ROSC. The time to ROSC in the NRP group was 7± 4 min. The only lamb that achieved ROSC in PALS took 18.9 min and went into arrest after 3 min. Since only one lamb briefly achieved ROSC with PALS, no comparisons/analyses were made with the four lambs that achieved ROSC with the NRP algorithm. Fig2a,2b,2c shows the peak coronary, carotid and pulmonary blood flows in lambs that did not achieve ROSC: NRP (N=2/6) & PALS (N=5/6). The blood flows were similar, and there were no differences in blood pressure during CPR. On average, there were ten pauses with PALS compared to 4 (before EPI administration) with NRP to check the rhythm. No differences in gas exchange were observed in ROSC lambs with both algorithms (Fig3a,3b,3c).

Conclusion: The NRP algorithm had higher ROSC rates than PALS, although this difference was not significant. PALS suggested EPI dose of 0.01mg/kg could have worsened the ROSC rate further. Frequent pauses in the PALS algorithm can explain the lower rates of ROSC observed in our study. Our study suggests using the NRP protocol for newborn resuscitation.