Early Surgery in Very Preterm Infants is Associated with Brain Abnormalities on Term MRI: A Propensity Score Analysis

ABSTRACT Objective To investigate the association between exposure to surgery under general anesthesia during the newborn period and brain abnormalities and neurodevelopmental outcomes in very preterm infants. We hypothesized that exposure to surgery under general anesthesia was associated with structural brain abnormalities on MRI at term-equivalent age and neurodevelopmental impairments at two years corrected age. Study design This prospective observational study includes 392 infants born at or below 32 weeks’ gestational age. Participants completed brain MRI at term-equivalent age and Bayley-III assessment at two years corrected age. We assessed the MRI global brain abnormality score as our primary outcome. Our secondary outcomes were scores on the Bayley-III Cognitive, Language, and Motor subscales. We evaluated the independent effects of surgery on brain MRI abnormalities and neurodevelopmental outcomes using ANOVA analyses after propensity score matching. Results All infants completed brain MRI, and 338 (86%) completed neurodevelopmental testing. Forty-five received surgery under general anesthesia. Exposure to surgery was associated with worse MRI abnormalities. None of the developmental outcomes was associated with surgery after propensity score matching. The global brain abnormality score was associated with the Bayley Cognitive and Motor composite scores. Conclusions Very preterm infants exposed to surgery under general anesthesia were at higher risk of brain abnormalities on MRI at term but not adverse neurodevelopmental outcomes at two years. Global brain abnormality score on MRI was associated with neurodevelopmental outcomes at two years. Brain MRI measures at term may function as sensitive intermediate measures of neurodevelopmental outcomes for very preterm infants.