Dr. Hartung is correct in pointing out that we erroneously stated that there were “no significant differences between the study groups and population norms.”1The purpose of our letter to the editor was not to disprove the hypothesis that “data obtained in rodents apply to humans” in the context of anesthetic neurotoxicity and the developing brain. This phenomenon should be examined in a formal prospective case–control study in humans with validated outcome measures. The point that we wanted to make in the graph was that, despite the severity of cardiac lesions and the operative conditions (i.e. , hypoxia,2prolonged anesthesia/sedation, and circulatory arrest/support), the mean neurocognitive outcomes at 4 and 8 yr were somewhat lower but within the normal range of the normative values (100 ± 15) of the general population.3,4Delayed repair of congenital heart disease is associated with progressive decrement of cognitive function and justifies early surgical intervention in neonates.5These data are not a direct test of the neurocognitive effects of prolonged anesthesia/sedation in human neonates but should provide some impetus for further investigations. To paraphrase Shakespeare in Love’s Labour’s Lost , “Beauty is bought by judgment of the eye, not utt’red by base sale of chapmen’s tongues.”6We acknowledge our utterance of incorrect statistical analysis of existing data and stand corrected. However, there are no existing human experimental data that clearly demonstrate the neurotoxic effect of anesthetics in pediatric patients.

*Children’s Hospital Boston, Boston, Massachusetts. sulpicio.soriano@childrens.harvard.edu

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Shakespeare W: Love’s Labour’s Lost. Act II, Scene i. 1598