Effects of dexmedetomidine sedation on the EEG in children

OBJECTIVES: To examine the effects of dexmedetomidine sedation on EEG background and epileptiform activity in children, comparing it to natural sleep. AIM: To provide quantitative and qualitative descriptions of the effect of dexmedetomidine sedation on the EEG of children. BACKGROUND: Children with intractable epilepsy admitted for surgery undergo 5 days of continuous EEG monitoring as well as nuclear medicine imaging studies with dexmedetomidine for sedation. Continuous EEG monitoring of each child during both natural sleep and dexmedetomidine-induced sedation provides a unique opportunity to evaluate the effects of dexmedetomidine on the EEG of children. MATERIALS/METHODS: Sixteen children undergoing dexmedetomidine sedation for nuclear medicine studies and simultaneous continuous EEG monitoring were studied. EEG segments during sedation were compared to samples of naturally occurring stage II sleep from the same child. Standard visual EEG analysis, quantification of delta, theta, alpha, beta, and total RMS power, number and location of spike foci, and frequency of spike activity were compared. RESULTS: The EEG during dexmedetomidine sedation resembled stage II sleep. During sedation, statistically significant increases in power of 16% for theta (P = 0.01), 21% for alpha (P = 0.03), and 40% for beta (P < 0.01) were observed, but not for delta (P = 0.63) or total EEG power (P = 0.61). Spike frequency increased by 47% during sedation but no new spike foci or seizures were observed. CONCLUSION: Dexmedetomidine sedation elicited an EEG pattern similar to that of Stage II sleep with modest increases in theta, alpha, and beta activity. Dexmedetomidine does not hinder interpretation of the EEG, suggesting that it may be a uniquely useful agent for EEG sedation in children.