Role of the bispectral index in sedation monitoring in the ICU.
OBJECTIVE
To review and critique evidence for the use of the bispectral index (BIS) in intensive care unit (ICU) patients.


METHODS
A computer search of English-language articles in MEDLINE (1966-July 2005), International Pharmaceutical Abstracts (1971-July 2005), and Scientific Citation Index Expanded (1980-July 2005) was conducted. A manual search of abstracts was also performed using the key search terms BIS, sedation, and critical care.


METHODS
Case series, letters, editorials, and clinical studies that evaluated BIS in ICU patients were considered for inclusion.


RESULTS
Nineteen studies comparing the BIS with sedation scales were evaluated, revealing that the BIS trends lower with increasing sedation. The BIS appeared to correlate better when sedation scores were grouped rather than individual values. However, correlations between BIS and subjective scales were low in most studies (r(2) 0.21-0.93). Additionally, there was poor correlation between drug dosage and the BIS. Randomized, controlled trials demonstrating improved outcomes with BIS monitoring have not been reported.


CONCLUSIONS
Interpreting literature on the usefulness of the BIS in the ICU is difficult for reasons that include heterogeneous populations, different methods of collecting BIS data, and use of different versions of BIS software and hardware. Outcomes data are lacking. The 2002 Society of Critical Care Medicine Sedation Guidelines recommendation that more data are needed before the BIS should be used routinely in the ICU remains unchanged. We recommend that further studies be conducted to determine the optimal method of obtaining BIS data and evaluate the impact of the BIS on relevant patient outcomes.
College of Pharmacy, The Ohio State University, Columbus, 43210, USA.
Jaclyn M
JM
LeBlanc
Joseph F
JF
Dasta
Sandra L
SL
Kane-Gill
D003422:Critical Care; D004569:Electroencephalography / Q000187:drug effects; D006801:Humans; D006993:Hypnotics and Sedatives / Q000494:pharmacology; D016896:Treatment Outcome
D006993:Hypnotics and Sedatives