Oxygenation of the newborn: a molecular approach.

In this review oxygenation and hyperoxic injury of newborn infants are described through molecular and genetic levels. Protection and repair mechanisms that may be important for a new understanding of oxidative stress in the newborn are discussed. The research summarized in this article represents a basis for the reduced oxygen supplementation and oxidative load of newborn babies, especially since the turn of the century. The mechanisms discussed may also contribute to an understanding of why hyperoxic resuscitation of the newborn may damage DNA and affect its repair, thus increasing the risk that it may be carcinogenic. Today, term babies should be resuscitated with air rather than 100% oxygen and very and extremely low birth weight infants in need of stabilization or resuscitation at birth should be administered initially 21-30% oxygen and the level should be titrated according to the response, preferably measured by pulse oximetry. In the postnatal period the oxygen saturation should be targeted low <95%; however, saturations between 85 and 89% seem to increase mortality. The optimal oxygen saturation target for these infants postnatally is still unknown.