Surgery requiring General Anesthesia in Preterm infants is associated with Altered Brain Volumes at Term Equivalent Age and Neurodevelopmental Impairment

BACKGROUND: To describe and contrast the brain development and outcome among very preterm infants, that were and were not exposed to surgery requiring general anesthesia prior to term equivalent age (TEA).. METHODS: Preterm infants born ≤30 weeks’ gestation that did (n=25) and did not (n=59) have surgery requiring general anesthesia during the preterm period were studied. At TEA, infants had MRI scans performed with measures of brain tissue volumes, cortical surface area, gyrification index and white matter microstructure. Neurodevelopmental follow-up with the Bayley Scales of Infant and Toddler Development, 3(rd) Edition was undertaken at two years corrected age. Multivariate models, adjusted for clinical and social risk factors, were used to compare the groups. RESULTS: After controlling for clinical and social variables, preterm infants exposed to surgical anesthesia demonstrated decreased relative white matter volumes at TEA, and lower cognitive and motor composite scores at two year follow-up. Those with longer surgical exposure demonstrated the greatest decrease in white matter volumes and lower cognitive and motor outcomes at age two years. CONCLUSION: Very preterm infants who required surgery during the preterm period had lower white mater volumes at TEA and worse neurodevelopemental outcome at age 2 years.