A comparison of bispectral index and spectral entropy during sevoflurane anesthesia in children

Choi, So Ron; Chung, Chan Jong; Park, Sang Won; Lee, Soo Il

Clinical Research

Pediatric Anesthesia

Anesthesia and Pain Medicine 2009;4(2):174-178.
Published online April 30, 2009.

A comparison of bispectral index and spectral entropy during sevoflurane anesthesia in children

So Ron Choi, Chan Jong Chung, Sang Won Park, Soo Il Lee

Department of Anesthesia and Pain Medicine, College of Medicine, Dong-A University, Busan, Korea. cjchung@dau.ac.kr

Abstract

BACKGROUND
Bispectral index (BIS) is a useful tool to assess depth of anesthesia. Recently, spectral entropy has been promoted as a monitor of anesthetic depth in adult, but its characteristics in children remains poorly defined. This study was to compare BIS and entropy indices during sevoflurane anesthesia in children.
METHODS
Forty children (aged 1-12 yr) scheduled for ENT surgery, were included. Anesthesia was induced with 5.0% sevoflurane in O2 6 L/min. Tracheal intubation was performed with rocuronium 0.6 mg/kg. Heart rate, blood pressure, end-tidal sevoflurane concentration (Etsev), BIS, response entropy (RE) and state entropy (SE) were measured every 5 minutes. The correlation between BIS and entropy index and Etsev was calculated, RESULTS: The BIS, SE and RE values decreased with induction and increased with recovery. The BIS, RE, and SE values were inversely proportionally related to the Etsev. The RE and SE values were closely correlated with the BIS values (respectively r = 0.948 and r = 0.946, P< 0.001).
CONCLUSIONS
We demonstrated a close correlation of SE and RE with Etsev and with BIS during sevoflurane anesthesia in children. State entropy and RE seem to be useful electroencephalographic measures of sevoflurane drug effect in children.

Key Words: bispectral index, pediatric anesthesia, sevoflurane, spectral entropy