Antenatal steroids have improved the survival of preterm infants; however, the mechanism of action is not fully understood. We aimed to establish an association between antenatal steroids and antioxidant activity and postnatal oxidative stress. In a prospective cohort study, extremely preterm neonates receiving antenatal steroids (CORT) or not (NOCORT) were enrolled. An association between antenatal steroids and activities of antioxidant enzymes and glutathione cycle enzymes in cord blood was found. In addition, reduced oxidative stress (GSH/GSSG ratio, CORT vs. NOCORT, 35.68 + or - 12.20 vs. 28.38 + or - 9.92; p < 0.01) and, decreased oxidation of proteins (ortho-tyrosine/phenylalanine ratio, CORT vs. NOCORT, 8.66 + or - 2.45 vs. 12.55 + or - 4.41; p < 0.01) and DNA (8oxodG/2dG ratio, CORT vs. NOCORT, 6.73 + or - 2.18 vs. 9.53 + or - 3.83; p < 0.01) also was found. Antenatal steroids were associated with reduced oxygen supplementation, mechanical ventilation, and conditions such as bronchopulmonary dysplasia, intra-periventricular hemorrhage, or retinopathy of prematurity. The maximal effectiveness was when steroids were administered 2-4 days before delivery. Female preterm infants had less oxidative stress and increased antioxidant activity and better clinical outcomes than did male infants, independent of receiving or not antenatal steroids. Antenatal steroids are accompanied by a reduction in postnatal oxidative-stress-derived conditions and increased antioxidant enzyme activity. Both these effects seem to be influenced by specific timing and female gender.

An increasing body of evidence has revealed that interventions performed during resuscitation of extremely-low-gestational-age neonates (ELGANs) may have a direct influence on the immediate survival and also on long-term morbidity. It has been proposed that interventions in the delivery room and/or hypothermia could trigger changes constitutive of chronic lung disease. New approaches in the first minutes of life using more gentle parameters of intervention are being studied. Thus, titrating inspiratory fraction of oxygen, the use of non-invasive ventilation to reduce trauma to the lung, the use of polyethylene/polyurethane wrapping to avoid hypothermia and delaying cord clamping altogether constitute promising initiatives. The first minutes of life are a valuable window for intervention. However, whilst these practice changes make sense and there are emerging data to support them, further evidence including long-term follow up is needed to definitively change resuscitation procedures in ELGANs.

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Surfactant administration using MIST, with no sedation, is feasible in preterm infants with RDS. No significant differences in secondary respiratory outcomes were found between the MIST and INSURE techniques.