Evaluation of Hemodynamic Data in an Ovine Model to Estimate Optimal Time for Compressor Change During Neonatal Resuscitation.

INTRODUCTION: Survival from cardiac arrest is directly and consistently linked to the quality of chest compressions (CC). Although compressor fatigue is well established, neonatal resuscitation guidelines (NRP) do not offer specific recommendations on rotation intervals beyond suggesting provider changes every 2-5 minutes. By comparison, Pediatric Advanced Life Support recommends a strict 2-minute rotation to prevent fatigue and maintain high-quality CC. METHODS: Prospective observational data from resuscitation of asphyxiated cardiac-arrested neonatal lambs to evaluate changes in chest compression rate, blood pressure, carotid blood flow with duration of CC by a single compressor. 41 near-term lambs were asphyxiated by umbilical cord occlusion until asystole resuscitated using NRP's synchronized three CC to one ventilation algorithm. RESULTS: The error rate of providing >3 or <3 CC between ventilations was <1%. CC rate and the percentage of lambs that received NRP's goal CC rate of 90/min decreased over time (p<0.005). After 91-120 seconds of chest compressions, CC rate decreased by 4% [3%,6%], carotid flow decreased by 21% [7%,35%], systolic blood pressure decreased by 3.1 [1.1,5.0] mmHg or 10% [3%,16%], and mean blood pressure decreased by 1.0 [0.3,1.7] or 7% [2%,12%] at the 95% confidence interval compared to baseline CC during the first 30 seconds (p<0.05). CONCLUSIONS: Extended duration of CC beyond 2 minutes is associated with a decrease in carotid blood flow, CC rate, systolic and mean arterial blood pressure. To maintain optimal cerebral perfusion in an ovine model of cardiac arrest, rotating compressors every two minutes may minimize fatigue-induced decrease in CC efficacy.