title: Monitoring sedation in critically ill patients: bispectral index, Ramsay and observer scales.
abstract: 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.
authors.affiliation: Hospital Universitario La Paz, Residencia General, Servicio de Anestesia-Reanimación, Madrid, Spain. mhgancedo@hotmail.com
authors.forename: C
authors.initials: C
authors.lastname: Hernández-Gancedo
authors.forename: D
authors.initials: D
authors.lastname: Pestaña
authors.forename: N
authors.initials: N
authors.lastname: Peña
authors.forename: C
authors.initials: C
authors.lastname: Royo
authors.forename: H
authors.initials: H
authors.lastname: Pérez-Chrzanowska
authors.forename: A
authors.initials: A
authors.lastname: Criado
mesh_terms: D000368:Aged; D000758:Anesthesia / Q000379:methods*; D016292:Procedural Sedation / Q000379:methods*; D003422:Critical Care / Q000379:methods; D004576:Electromyography; D005260:Female; D005283:Fentanyl / Q000008:administration & dosage / Q000009:adverse effects; D006801:Humans; D008297:Male; D008874:Midazolam / Q000008:administration & dosage / Q000009:adverse effects; D016343:Monitoring, Intraoperative / Q000379:methods*; D015742:Propofol / Q000008:administration & dosage / Q000009:adverse effects; D011446:Prospective Studies; D012372:ROC Curve
chemical_list: D008874:Midazolam; D005283:Fentanyl; D015742:Propofol