Resuscitation with room air instead of 100% oxygen prevents oxidative stress in moderately asphyxiated term neonates.

Background. Traditionally, asphyxiated newborn infants have been ventilated using 100% oxygen. However, a recent multinational trial has shown that the use of room air was just as efficient as pure oxygen in securing the survival of severely asphyxiated newborn infants. Oxidative stress markers in moderately asphyxiated term newborn infants resuscitated with either 100% oxygen or room air have been studied for the first time in this work. Methods. Eligible term neonates with perinatal asphyxia were randomly resuscitated with either room air or 100% oxygen. The clinical parameters recorded were those of the Apgar score at 1, 5, and 10 minutes, the time of onset of the first cry, and the tim…

Oxidative stress in asphyxiated term infants resuscitated with 100% oxygen

Although room air is adequate for resuscitating asphyxiated newborn infants, guidelines recommend using 100% oxygen. Hyperoxemia, as has been noted in animal studies, could cause delayed breathing, increased oxygen consumption, and disordered cerebral circulation. In addition, 100% oxygen has caused prolonged oxidation of blood glutathione in neonates. In this study, 51 asphyxiated neonates born at term were randomly assigned to resuscitation with room air (RAR) and 55 to resuscitation with 100% oxygen (OxR). The goal was to learn whether using oxygen for resuscitation triggers oxidative stress. Critical criteria were the Apgar score, the time of the first cry, and sustained respiration. Si…

Hyperoxemia caused by resuscitation with pure oxygen may alter intracellular redox status by increasing oxidized glutathione in asphyxiated newly born infants

In a prospective, randomized, blinded trial we have studied the effects of resuscitation upon oxygenation in a group of asphyxiated newly born infants receiving room air or 100% oxygen as the gas source. During the acute phase of asphyxia and until the resuscitation procedure concluded, we determined serial blood gases as well as reduced and oxidized glutathione, enzymes involved in the glutathione redox cycle, and antioxidant enzyme activities. The use of 100% oxygen caused a remarkable increase of partial pressures of oxygen in arterial blood, with values that were frequently above physiological levels (>100 mm Hg). In addition, we have found a significant correlation between hyperoxemia …

L-cysteine and glutathione metabolism are impaired in premature infants due to cystathionase deficiency.

There are conflicting reports in the literature as to whether L-cysteine is an essential amino acid in premature infants as the result of the absence of hepatic cystathionase activity. To analyze the physiological importance of the cystathionase deficiency, we studied sulfur amino acid metabolism in human neonates of different gestational ages. Plasma cystathionine concentrations are higher in premature infants < or = 32 wk gestation (group 1) than in premature infants of 33-36 wk gestational age (group 2) or in full-term infants (group 3), whereas plasma cysteine concentrations are much lower in group 1 and 2 premature infants than in mature infants. Furthermore, erythrocytes from group 1 …

Resuscitation of Term Neonates with Moderate Asphyxia with Room Air or Oxygen: Consequences on the Glutathione Metabolism