Oxidative stress in asphyxiated term infants resuscitated with 100% oxygen.
OBJECTIVE
To test the hypothesis that resuscitation of asphyxiated infants with pure oxygen causes hyperoxemia and oxidative stress.Study design Asphyxiated term newborn infants (n = 106) were randomly resuscitated with room air (RAR = 51) or 100% oxygen (OxR = 55). The Apgar score, time of the first cry, and establishment of a sustained pattern of respiration were recorded. Assays performed included: blood gases; reduced glutathione (GSH) and oxidized glutathione (GSSG) in whole blood; glutathione-related enzyme activities; and superoxide dismutase activity (SOD) in erythrocytes.


RESULTS
The RAR group needed less time of ventilation for resuscitation (5.3 +/- 1.5 vs 6.8 +/- 1.2 min; P <.05). Pure oxygen caused hyperoxemia (PO(2), 126.3 +/- 21.8 mm Hg) that did not occur with the use of room air (PO(2), 72.2 +/- 6.8 mm Hg). GSH was decreased and GSSG, the glutathione cycle enzymes, and SOD activities were increased in both asphyxiated groups. However, the 100% oxygen-resuscitated group showed significantly greater alterations that correlated positively with hyperoxemia.


CONCLUSIONS
Asphyxia causes oxidative stress in the perinatal period, and resuscitation with 100% oxygen causes hyperoxemia and increased oxidative stress. Because there are no advantages to resuscitation with 100% oxygen, room air may be preferred under certain circumstances for the resuscitation of asphyxiated neonates.
Vento
Máximo
M
School of Medicine, University of Alicante, Department of Pediatrics and Neonatology and Division of Neonatology, Hospital Virgen del Consuelo, Valencia, Spain. maximo.vento@uv.es
Asensi
Miguel
M
Sastre
Juan
J
Lloret
Ana
A
García-Sala
Fernando
F
Viña
José
J
D001034:Apgar Score; D001238:Asphyxia Neonatorum / Q000378:metabolism / Q000628:therapy*; D002245:Carbon Dioxide / Q000097:blood; D004311:Double-Blind Method; D005312:Fetal Blood / Q000737:chemistry; D005978:Glutathione / Q000097:blood; D019803:Glutathione Disulfide / Q000097:blood; D005980:Glutathione Reductase / Q000097:blood; D006801:Humans; D007231:Infant, Newborn; D018384:Oxidative Stress; D010100:Oxygen / Q000097:blood; D010102:Oxygen Inhalation Therapy / Q000009:adverse effects; D012151:Resuscitation; D013482:Superoxide Dismutase / Q000097:blood
D002245:Carbon Dioxide; D013482:Superoxide Dismutase; D005980:Glutathione Reductase; D005978:Glutathione; D010100:Oxygen; D019803:Glutathione Disulfide