Achieved oxygen saturations and retinopathy of prematurity in extreme preterms

To identify achieved oxygen saturations (SpO₂) associated with increased risk of severe retinopathy of prematurity (ROP).

This is a secondary analysis of the Surfactant Positive Airway Pressure and Pulse Oximetry Trial (SUPPORT)randomised controlled trial. SpO₂ was recorded up to 36 weeks' postmenstrual age. Saturations through 9 postnatal weeks were explored graphically, and logistic regression models were created to predict severe ROP.

20 centres of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network.

984 surviving infants of 24-27 weeks' gestational age born in 2005-2009.

SUPPORT targeted SpO₂ to a lower (85%-89%) or higher (91%-95%) range through 36 weeks' postmenstrual age or off respiratory support.

Severe ROP defined as threshold ROP, ophthalmological surgery or bevacizumab treatment.

There were statistically significant interactions between duration of oxygen supplementation and percentage of time in certain achieved saturation ranges. Specifically, for infants who spent at least 2 weeks on oxygen in postnatal weeks 1-5, a higher percentage of time at 91%-96% SpO₂ was associated with increased odds of severe ROP. For infants who spent at least 3 weeks on oxygen in postnatal weeks 6-9, a higher percentage of time at 97%-100% SpO₂ was associated with increased odds of severe ROP. Other significant risk factors were lower gestational age and birth weight, non-Hispanic white versus black race, prospectively defined severe illness, late-onset sepsis or meningitis, and clinical centre.

Among extremely preterm survivors to discharge, the association between SpO₂ and severe ROP depended on the timing and duration of oxygen supplementation.