Abstract

Data on the effects of analgesics and sedatives on the brain are needed to develop safe and effective treatments during neonatal intensive care. Electroencephalography (EEG) is an objective but interpretation-dependent method for monitoring cortical activity. Quantitative computational analysis can reveal changes in the EEG that are otherwise undetectable. EEG recordings were retrospectively collected from her 21 infants (mean gestational age 38.7 weeks,range 27–42) who received dexmedetomidine during neonatal care. Registrations were converted to computational functions and analyzed visually, using two computational measures to determine relative and absolute changes in performance (regional EEG; rEEG) and cortico-cortical synchrony (Activation Synchronicity Index; ASI). were quantified respectively. Visual assessment did not reveal any drug effects. rEEG analysis found a negative correlation between baseline and reference frontal (rho = 0.612, p = 0.006) and parietal (rho = -0.489, p = 0.035) leads. ASI changes were negatively correlated with interhemispheric baseline values (rho = -0.753; p = 0.001) and frontal comparisons (rho = -0.496; p = 0.038). Dexmedetomidine brain effects as determined by neonatal EEG were associated with pre- DEX cortical activity, with higher levels of brain activity during baseline (higher rEEG) leading to more pronounced reductions with DEX. Computational measurements show drug effects on both global cortical activity and corticocortical communication. These effects were not evident by visual analysis.