Oxygen Use in Neonatal Care: A Two-edged Sword

Area of Science:

• Neonatology
• Biochemistry
• Pediatric Medicine

Background:

• Oxygen therapy in neonates requires careful consideration of both benefits and toxicity.
• Reactive oxygen species (ROS), such as hydroxyl radical (OH•), are potent oxidants implicated in cellular damage.
• Oxidative stress, an imbalance between ROS production and antioxidant defenses, can lead to significant pathological consequences.

Purpose of the Study:

• To review the mechanisms and consequences of neonatal oxidative stress.
• To discuss the role of hyperoxia in neonatal tissue injury.
• To provide evidence-based recommendations for safe oxygen saturation monitoring in neonates.

Main Methods:

• Literature review of studies on neonatal oxidative stress, ROS generation, and antioxidant capacity.
• Analysis of mechanisms contributing to increased ROS production in neonates.
• Evaluation of clinical evidence regarding optimal oxygen saturation targets.

Main Results:

• Preterm newborns exhibit lower antioxidant capacity compared to term infants.
• Key ROS generation mechanisms include mitochondrial respiration, iron reactions, inflammation, hypoxia/ischemia, reperfusion, and hyperoxia.
• Hyperoxia-induced oxidative stress is linked to injuries in the lungs, central nervous system, retina, and red blood cells.

Conclusions:

• Neonatal oxidative stress results from decreased antioxidants and/or increased ROS, with preterm infants being particularly vulnerable.
• Avoiding fluctuations in oxygen saturation (SpO2) is critical during supplemental oxygen therapy.
• Setting SpO2 alarm limits between 90% and 95% is recommended to mitigate risks of hypoxia and hyperoxia, although further research on antioxidant interventions is ongoing.