Targeted Oxygen in the Resuscitation of Preterm Infants, a Randomized Clinical Trial

Lower concentrations of oxygen (O₂) (≤30%) are recommended for preterm resuscitation to avoid oxidative injury and cerebral ischemia. Effects on long-term outcomes are uncertain. We aimed to determine the effects of using room air (RA) or 100% O₂ on the combined risk of death and disability at 2 years in infants <32 weeks' gestation.

A randomized, unmasked study designed to determine major disability and death at 2 years in infants <32 weeks' gestation after delivery room resuscitation was initiated with either RA or 100% O₂ and which were adjusted to target pulse oximetry of 65% to 95% at 5 minutes and 85% to 95% until NICU admission.

Of 6291 eligible patients, 292 were recruited and 287 (mean gestation: 28.9 weeks) were included in the analysis (RA: n = 144; 100% O₂: n = 143). Recruitment ceased in June 2014, per the recommendations of the Data and Safety Monitoring Committee owing to loss of equipoise for the use of 100% O₂. In non-prespecified analyses, infants <28 weeks who received RA resuscitation had higher hospital mortality (RA: 10 of 46 [22%]; than those given 100% O₂: 3 of 54 [6%]; risk ratio: 3.9 [95% confidence interval: 1.1-13.4]; P = .01). Respiratory failure was the most common cause of death (n = 13).

Using RA to initiate resuscitation was associated with an increased risk of death in infants <28 weeks' gestation. This study was not a prespecified analysis, and it was underpowered to address this post hoc hypothesis reliably. Additional data are needed.