Targeting survival without morbidity: Heart rate characteristics for oxygen supplementation optimization in neonatal care

The preterm newborn is susceptible to many diseases related to oxidative stress, and supplemental oxygen therapy and its interaction with inflammatory processes may be a contributing factor to their underlying pathophysiology. Supplemental oxygen therapy can lead to over-oxygenation, and can complicate ischemia–reperfusion processes, which in turn can promote oxidative stress pathways. We hypothesize that the optimal dose of supplemental oxygen therapy likely varies for each preterm infant based on their unique and developing physiology, and may be adjusted through the assessment autonomic nervous function and pulmonary resilience by measuring heart rate variability. We present preliminary findings demonstrating that among extremely preterm infants with low-to-moderate heart rate characteristics index (HRCi) scores (indicating healthy ANS function) during the first six postnatal days, exposure to a low target oxygen saturation range was associated with decreased risk of the composite outcome of death by 36 weeks postmenstrual age (PMA), necrotizing enterocolitis (NEC), bronchopulmonary dysplasia (BPD), and/or retinopathy of prematurity (ROP). This suggests a novel therapeutic approach to supplemental oxygen delivery in the neonatal intensive care unit (NICU) wherein the HRCi can be leveraged to guide the prescription of individualized target oxygen saturation ranges that are responsive to each infant’s unique and dynamic physiology, minimizing the risks of morbidity and mortality.