ABSTRACT
Reactive oxygen species (ROS) and reactive nitrogen species (RNS) alter biomolecular structure and function. Biochemical immaturity of the preterm newborn limits antioxidant defenses. ROS formation may be favored through sudden transition from the relatively hypoxic fetal environment to markedly increased oxygen. Resuscitation with 21% rather than 100% oxygen may minimize early oxidative stress (1). Intubation and mechanical ventilation are associated with inflammation and therefore additional oxidative (2) and nitrosative stress (3). Chorioamnionitis may contribute to early, even prenatal, oxidative stress in the preterm newborn (4). Likewise, the preterm newborn is predisposed to infection that can compound inflammation and oxidative stress.
