Anesthesia, extremely premature infants and full-scale intelligence quotient at 5 years of age

Background: To determine the association between exposure to Food and Drug Administration (FDA) warned anesthetics in premature infants and their full-scale intelligence quotient (FSIQ) score at 5 years of age. Methods: Premature infants born <27 weeks gestational age (GA) between January 2006 and December 2012 with FDA anesthetic exposure status were included. Exposures included volatile anesthetics, propofol, benzodiazepines, ketamine, chloral hydrate, and barbiturates/phenobarbital. Exposure was treated as a binary variable with infants stratified into those who were or were not exposed to any FDA warned drug. Associations were explored using univariable and multivariable regressions. Results: 238 (61.5%) of 387 eligible infants had available FSIQ scores. Of these, 110 (46.2%) were exposed to warned anesthetics. Unadjusted and adjusted imputed case associations (95% CI) between FDA warned anesthetics and FSIQ were -5 (-10 to -2, p = 0.014) and -2 (-7 to 3, p = 0.528) points. An unobserved confounder(s) the strength of severe IVH [-9 points (-15 to -3)] would be required to overturn the directional association between FDA exposure and FSIQ in our complete case model. Conclusion: Premature infants exposed to anesthetics flagged by the FDA showed no significant reduction in FSIQ at 5 years of age.