Efficacy of supplemental oxygen in reducing the need for laser or intravitreal bevacizumab in preterm infants with stage 2 retinopathy of prematurity

Abstract

Background: Retinopathy of prematurity (ROP) is a disease that affects preterm infants born younger than 30 weeks of gestation. The pathophysiology of ROP involves an initial vaso-obliterative phase followed by vaso-proliferative phase that leads to disease progression. The use of supplemental oxygen during the vaso-proliferative phase of ROP has been associated with reduced disease progression, but how this impacts the need for ROP treatment is unclear. The goal of this study was to compare the rate of laser or intravitreal bevacizumab after implementation of a new supplemental oxygen therapy protocol in preterm infants with stage 2 ROP. Methods: This is a retrospective chart review of preterm infants diagnosed with stage 2 ROP at Riley Hospital for Children between 1/2017 and 12/2022. Patients diagnosed between 1/2017 and 6/2020 were classified as Cohort A, preprotocol implementation. Patients diagnosed from 8/2020 to 12/2022 were classified as Cohort B, postprotocol implementation. In Cohort A, oxygen saturation was kept at 91-95% through the entire hospitalization. In Cohort B, oxygen saturation was increased to 97-99% as soon as Stage 2 ROP was diagnosed. Statistical analyses were performed using chi-square and Student's T test, followed by multivariate analyses to determine the impact of the oxygen protocol on the need for ROP treatment. Results: A total of 211 patients were diagnosed with stage 2 ROP between 1/2017 and 12/2022. Of those patients, 122 were before protocol implementation therapy (Cohort A), and 89 were after implementation of supplemental oxygen protocol (Cohort B). Gestational age was slightly higher in Cohort B (Cohort A 25.3 ± 1.9, Cohort B 25.8 ± 1.84, p = 0.04). There was no difference in birth weight, NEC, BPD, or survival. Cohort B had lesser need for invasive mechanical ventilation and higher days on CPAP during hospitalization. Notably, Cohort A had 67 (55%) patients treated with laser photocoagulation or intravitreal bevacizumab versus 20 (22%) patients in Cohort B (OR 0.19, 0.08-0.40). Conclusion: The need for laser photocoagulation or intravitreal bevacizumab was significantly decreased in high-risk patients treated with the supplemental oxygen protocol. This result supports the idea that targeted supplemental oxygen therapy to keep saturations between 97 and 99% can reduce disease progression in infants with stage 2 ROP and potentially decrease the burden of additional procedures.