Sedation for electroencephalography with dexmedetomidine or chloral hydrate: a comparative study on the qualitative and quantitative electroencephalogram pattern.
BACKGROUND
Sedation for electroencephalography in uncooperative patients is a controversial issue because majority of sedatives, hypnotics, and general anesthetics interfere with the brain's electrical activity. Chloral hydrate (CH) is typically used for this sedation, and dexmedetomidine (DEX) was recently tested because preliminary data suggest that this drug does not affect the electroencephalogram (EEG). The aim of the present study was to compare the EEG pattern during DEX or CH sedation to test the hypothesis that both drugs exert similar effects on the EEG.


METHODS
A total of 17 patients underwent 2 EEGs on 2 separate occasions, one with DEX and the other with CH. The EEG qualitative variables included the phases of sleep and the background activity. The EEG quantitative analysis was performed during the first 2 minutes of the second stage of sleep. The EEG quantitative variables included density, duration, and amplitude of the sleep spindles and absolute spectral power.


RESULTS
The results showed that the qualitative analysis, density, duration, and amplitude of sleep spindles did not differ between DEX and CH sedation. The power of the slow-frequency bands (δ and θ) was higher with DEX, but the power of the faster-frequency bands (α and β) was higher with CH. The total power was lower with DEX than with CH.


CONCLUSIONS
The differences of DEX and CH in EEG power did not change the EEG qualitative interpretation, which was similar with the 2 drugs. Other studies comparing natural sleep and sleep induced by these drugs are needed to clarify the clinical relevance of the observed EEG quantitative differences.
*Serviço de Anestesiologia da Santa Casa de Misericórdia de Belo Horizonte †Serviço de Neurologia da Santa Casa de Misericórdia de Belo Horizonte ‡Departamento de Cirurgia da Faculdade de Medicina da Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, Minas Gerais, Brazil.
Magda L
ML
Fernandes
Welser Machado de
WM
Oliveira
Maria do Carmo Vasconcellos
Mdo C
Santos
Renato S
RS
Gomez
D000328:Adult; D002697:Chloral Hydrate; D016292:Procedural Sedation / Q000379:methods*; D020927:Dexmedetomidine; D004311:Double-Blind Method; D004569:Electroencephalography / Q000379:methods*; D005260:Female; D006801:Humans; D006993:Hypnotics and Sedatives; D007022:Hypotension / Q000139:chemically induced; D008297:Male; D011446:Prospective Studies; D012890:Sleep / Q000187:drug effects; D012894:Sleep Stages / Q000187:drug effects; D055815:Young Adult
D006993:Hypnotics and Sedatives; D002697:Chloral Hydrate; D020927:Dexmedetomidine