Resuscitation of preterm infants with different inspired oxygen fractions.

OBJECTIVE: To test the hypothesis that an initial fraction of inspired oxygen (FiO2) of 30% during resuscitation of preterm infants results in less oxidative stress and is associated with improved clinical outcomes compared with an FiO2 of 65%.

STUDY DESIGN: Preterm infants of gestational age <32 weeks (n = 193) were randomized to start resuscitation with either 30% oxygen (low-oxygen group) or 65% oxygen (high-oxygen group), after which the FiO2 was adjusted based on oxygen saturation values. The primary outcome was bronchopulmonary dysplasia (BPD) assessed at 36 weeks postmenstrual age. Secondary outcomes included major neonatal illnesses and markers of oxidative stress.

RESULTS: The median gestational age of included infants was 28(6)/7 weeks (IQR, 26(5)/7-30(3)/7 weeks). The incidence of BPD was not significantly different between the low-oxygen and high-oxygen groups (24% vs. 17%; P = .15). The FiO2 in both groups was adjusted to a mean of 40% by 7 minutes in the low-oxygen group and by 11 minutes in the high-oxygen group. No differences in markers of oxidative stress were noted between groups.

CONCLUSION: Initial supplementation of preterm infants with 30% oxygen during the fetal-to-neonatal transition is as safe as 65% oxygen, with no differences in oxidative stress markers or BPD.