Premium
BIS and Entropy in the elderly
Author(s) -
Arnold G.,
Kluger M.,
Voss L.,
Sleigh J.
Publication year - 2007
Publication title -
anaesthesia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.839
H-Index - 117
eISSN - 1365-2044
pISSN - 0003-2409
DOI - 10.1111/j.1365-2044.2007.05149.x
Subject(s) - medicine , bispectral index , general anaesthesia , anesthesia , electroencephalography , population , pathological , hypnotic , surgery , propofol , psychiatry , environmental health
Summary The interaction of many poorly defined, physiological, pharmacological, and pathological factors make titration of general anaesthesia in the elderly difficult. There may be a potential clinical benefit using the processed electroencephalogram (EEG) to monitor hypnotic level in this population. We prospectively studied 16 patients aged over 65 years having hip fractures repaired under general anaesthesia by experienced anaesthetists blinded to Bispectral Index (BIS XP ) and Entropy values. Pre‐induction EEG indices did not correlate with age or mini‐mental state examination (MMSE). During maintenance of anaesthesia, BIS XP and Response Entropy (RE) values were within the recommended range of 40–60, 45% and 32% of the total time, respectively. BIS XP and Response Entropy (RE) values were above 60 for 11% and 13% of the total time, respectively, and below 40 for 44% and 55% of the total time, respectively. BIS XP correlated well with RE in 12 patients, but in the other four patients there was a difference of more than 20 points between BIS XP and RE.