Oxygen Saturation and Outcomes in Preterm Infants

This report of the three BOOST II trials, undertaken to examine optimum oxygen saturation in extremely preterm infants, showed that targeting levels below 90% with the use of current oximeter calibrations was associated with increased mortality. The clinically appropriate range for oxygen saturation in preterm infants is unknown. Trials in the 1950s showed that unrestricted oxygen increased the rate of severe retinopathy of prematurity. However, when oxygen was subsequently restricted, increased mortality was observed. 1 The first Benefits of Oxygen Saturation Targeting (BOOST) trial showed that in preterm infants who were still receiving oxygen at 32 weeks' gestation, targeting a higher oxygen-saturation range prolonged oxygen dependence. 2 Observational studies suggested that higher oxygen-saturation levels may increase rates of retinopathy of prematurity. 3 – 5 In five randomized, masked trials with similar protocols conducted in the United States, 6 Australia, New Zealand, . . .