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Monitoring sedation in critically ill patients: bispectral index, Ramsay and observer scales

Published online by Cambridge University Press:  27 January 2006

C. Hernández-Gancedo ,
D. Pestaña ,
N. Peña ,
C. Royo ,
H. Pérez-Chrzanowska  and
A. Criado
C. Hernández-Gancedo
Affiliation:
Hospital Universitario La Paz, Residencia General, Servicio de Anestesia-Reanimación, Madrid, Spain
D. Pestaña
Affiliation:
Hospital Universitario La Paz, Residencia General, Servicio de Anestesia-Reanimación, Madrid, Spain
N. Peña
Affiliation:
Hospital Universitario La Paz, Residencia General, Servicio de Anestesia-Reanimación, Madrid, Spain
C. Royo
Affiliation:
Hospital Universitario La Paz, Residencia General, Servicio de Anestesia-Reanimación, Madrid, Spain
H. Pérez-Chrzanowska
Affiliation:
Hospital Universitario La Paz, Residencia General, Servicio de Anestesia-Reanimación, Madrid, Spain
A. Criado
Affiliation:
Hospital Universitario La Paz, Residencia General, Servicio de Anestesia-Reanimación, Madrid, Spain
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Extract

Summary

Background and objective: Sedation is commonly required by critically ill patients and inadequate sedation may be hazardous. Traditionally, subjective scales have been used for monitoring sedation. Bispectral index has been proposed, although its utility in the intensive care unit is debated. Our aim was to evaluate the depth of sedation in intubated surgical critically ill patients by means of two sedation scales (Ramsay and Observer's Assessment of Alertness and Sedation) and bispectral index. Methods: Sedation was assessed prospectively in 50 postoperative intubated patients requiring at least 24 h of sedation (35 propofol, 15 midazolam/fentanyl), every 8 h for a 24 -h period. The bispectral index value recorded was the mean value obtained during a 10-min observation period, whenever the quality signal index was above 75% and the electromyographic signal was below 25%. Results: Most of the patients (78%) were oversedated (bispectral index < 60). The three sedation scores (global data) correlated significantly (P < 0.001). This correlation was lost in the midazolam group in which the patients were also significantly more sedated than the propofol group (P = 0.001). The correlation between the bispectral index and the scales in the midazolam group reappeared when the measurements with a Ramsay = 6 or an Observer's Assessment of Alertness and Sedation = 1 were excluded. Conclusions: Sedation should be monitored routinely in intensive care units. The Ramsay and the Observer's Assessment of Alertness and Sedation scales showed equal efficacy. Bispectral index might prove useful for discriminating between deeper levels of sedation.

Keywords

INTENSIVE CARESEDATION, propofol, midazolam, fentanylMONITORING, bispectral index, sedation scoring
Type
Original Article
Information
European Journal of Anaesthesiology , Volume 23 , Issue 8 , August 2006 , pp. 649 - 653
Copyright
© 2006 European Society of Anaesthesiology

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