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 and the intra-erythrocyte GSSG (oxidized glutathione) concentration. We hypothesize that hyperoxemia may be 1 of the triggering factors responsible for an increased oxidation of GSH (reduced glutathione). Moreover, an increased antioxidant enzyme activity, which reflects an oxidative stress, indicates that the antioxidant capacity of the newly born infant may have been surpassed.
Vento
Máximo
M
Servicio de Pediatría y Neonatología, Hospital Virgen del Consuelo, Valencia, Spain. maximo.vento@uv.es
Asensi
Miguel
M
Sastre
Juan
J
Lloret
Ana
A
García-Sala
Fernando
F
Miñana
Juan Bautista
JB
Viña
José
J
D000388:Air; D001034:Apgar Score; D001238:Asphyxia Neonatorum / Q000188:drug therapy*; D001784:Blood Gas Analysis; D005978:Glutathione / Q000097:blood; D019803:Glutathione Disulfide / Q000097:blood*; D005979:Glutathione Peroxidase / Q000097:blood; D005980:Glutathione Reductase / Q000097:blood; D005982:Glutathione Transferase / Q000097:blood; D006801:Humans; D018496:Hyperoxia / Q000097:blood / Q000139:chemically induced*; D007231:Infant, Newborn; D010084:Oxidation-Reduction; D010100:Oxygen / Q000008:administration & dosage / Q000009:adverse effects* / Q000097:blood; D010102:Oxygen Inhalation Therapy / Q000009:adverse effects*; D011446:Prospective Studies; D012151:Resuscitation / Q000009:adverse effects / Q000379:methods*; D018709:Statistics, Nonparametric
D005979:Glutathione Peroxidase; D005980:Glutathione Reductase; D005982:Glutathione Transferase; D005978:Glutathione; D010100:Oxygen; D019803:Glutathione Disulfide