Rosemarie de Ridder, Stephanie Balink, Wes Onland, Peter Dijk, Anthon Hulsmann, Anton van Kaam, André Kroon, Maruschka Merkus, Irwin Reiss, Arwen Sprij, Elianne Vrijlandt, Mariëlle Pijnenburg
Background: Supplemental oxygen remains the primary treatment for preterm infants with bronchopulmonary dysplasia (BPD). However, evidence on lower oxygen saturation (SpO2) targets beyond 36 weeks postmenstrual age (PMA) is lacking.
Aim: To assess the effect of an SpO2 lower limit of 95% compared with 90% on weight standard deviation score (SDS), as proxy for lung growth, at 6 months corrected age (CA) in infants with BPD.
Methods: The Supplemental Oxygen Strategies in children with BronchoPulmonary Dysplasia (SOS BPD) study was a multicenter non-blinded randomized controlled trial in the Netherlands. Preterm infants with moderate or severe BPD were randomized between 36-38 weeks PMA to receive an SpO2 lower limit of 90% (n=102) or 95% (n=99), until respiratory support was successfully stopped. The primary outcome was weight SDS at 6 months CA. Twenty-four prespecified secondary outcomes were analyzed up to 6 months CA.
Results: The mean gestational age was 27 weeks, and 46.7% was male. Mean (SD) weight SDS at 6 months CA was -0.9 (1.2) in the 95% group, and -0.8 (1.2) in the 90% group (mean difference -0.16, 95%CI -0.46 to 0.13). Compared with the 90% group, infants in the 95% group had a longer duration of respiratory support (median 41.0 vs 31.5 days, hazard ratio (HR) 0.60, 95%CI 0.44 to 0.81) and a higher PMA at discontinuation of respiratory support (median 42.9 vs 41.1 weeks, median difference 2.6, 95%CI 1.4 to 4.0). Other secondary outcomes were not different.
Conclusion: Targeting an SpO2 lower limit of 95% compared with 90% did not improve weight SDS at 6 months CA in infants with established BPD. No other clinical benefits of the higher SpO2 lower limit were observed. Follow-up studies are needed to assess the impact on long-term neurodevelopment and lung function.