Hostname: page-component-586b7cd67f-vdxz6 Total loading time: 0 Render date: 2024-11-23T01:47:54.044Z Has data issue: false hasContentIssue false
  • English
  • Français

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
Get access

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

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Young C, Knudsen N, Hilton A, Reves JG. Sedation in the intensive care unit. Crit Care Med 2000; 28: 854–866.Google Scholar
Sydow M, Neumann P. Sedation for the critically ill. Intens Care Med 1999; 25: 634–636.Google Scholar
Soliman HM, Mélot C, Vincent J-L. Sedative and analgesic practice in the intensive care unit: the results of a European survey. Br J Anaesth 2001; 87: 186–192.Google Scholar
Meyer TJ, Eveloff SE, Bauer MS et al. Adverse environmental conditions in the respiratory and medical ICU settings. Chest 1994; 105: 1211–1216.Google Scholar
De Jonghe B, Cook D, Appere-De-Vecchi C, Guyatt G, Meade M, Outin H. Using and understanding sedation scoring systems: a systematic review. Intens Care Med 2000; 26: 275–285.Google Scholar
Koller MH, Levy NT, Ahrens TS et al. The use of continuous i.v. sedation is associated with prolongation of mechanical ventilation. Chest 1998; 114: 541–548.Google Scholar
Kress JP, Pohlman AS, O'Connor MF, Hall JB. Daily interruption of sedative infusions in critically ill patients undergoing mechanical ventilation. N Engl J Med 2000; 342: 1471–1477.Google Scholar
Rello J, Diaz E, Roque M, Valles J. Risk factors for developing pneumonia within 48 hours of intubation. Am J Respir Crit Care Med 1999; 159: 1742–1746.Google Scholar
Sebel PS, Lang E, Rampil IJ et al. A multicenter study of bispectral electroencephalogram analysis for monitoring anesthetic effect. Anesth Analg 1997; 84: 891–899.Google Scholar
Frenzel D, Greim C-A, Sommer C et al. Is the bispectral index appropriate for monitoring the sedation level of mechanically ventilated surgical ICU patients? Intens Care Med 2002; 28: 178–183.Google Scholar
Nasraway SA, Wu EC, Kelleher RM et al. How reliable is the bispectral index in critically ill patients? A prospective, comparative, single-blinded observer study. Crit Care Med 2002; 30: 1483–1487.Google Scholar
Ramsay MAE, Savege TM, Simpson BRJ, Goodwin R. Controlled sedation with alphaxalone–alphadolone. BMJ 1974; 2: 656–659.Google Scholar
Chernik DA, Gillings D, Laine H et al. Validity and reliability of the observer's assessment of alertness/sedation scale: study with intravenous midazolam. J Clin Psychopharmacol 1999; 10: 244–251.Google Scholar
Andrzejowski J, Sleigh JW, Johnson AT, Sikiotis L. The effect of intravenous epinephrine on the bispectral index and sedation. Anaesthesia 2000; 55: 761–763.Google Scholar
Bailey JM. Pharmacokinetic–pharmacodynamic modeling and ICU sedation. Anesthesiology 2001; 95: 281–282.Google Scholar
Barr J, Zomorodi K, Bertaccini EJ et al. A double-blind, randomized comparison of iv lorazepam versus midazolam for sedation of ICU patients via a pharmacologic model. Anesthesiology 2001; 95: 286–298.Google Scholar
Ostermann ME, Keenan SP, Seiferling RA, Sibbald WJ. Sedation in the intensive care unit. A systematic review. JAMA 2000; 283: 1451–1459.Google Scholar
Hansen-Flaschen J, Coven J, Polomano RC. Beyond the Ramsay scale: need for a validated measure of sedating drug efficacy in the intensive care unit. Crit Care Med 1994; 22: 732–733.Google Scholar
Avramov MN, White PF. Methods for monitoring the level of sedation. Crit Care Clin 1995; 11: 802–826.Google Scholar
Rampil IJ. A primer for EEG signal processing in anesthesia. Anesthesiology 1998; 89: 980–1002.Google Scholar
Simmons L, Ricker R, Prato S, Fraser G. Assessing sedation during intensive care unit mechanical ventilation with the Bispectral Index and Sedation–Agitation Scale. Crit Care Med 1999; 27: 1499–1504.Google Scholar
Liu J, Singh H, White PF. Electroencephalogram bispectral analysis predicts the depth of midazolam-induced sedation. Anesthesiology 1999; 84: 64–69.Google Scholar
Liu J, Singh H, White PF. Electroencephalographic bispectral index correlates with intraoperative recall and depth of propofol induced sedation. Anesth Analg 1997; 84: 185–189.Google Scholar
Glass PS, Bloom M, Kearse L et al. Bispectral analysis measures sedation and memory effects of propofol, midazolam, isofluorane, and alfentanil in healthy volunteers. Anesthesiology 1997; 86: 836–847.Google Scholar
Bruhn J, Bouillon T, Shafer S. Electromyographic activity falsely elevates the bispectral index. Anesthesiology 2000; 92: 1485–1487.Google Scholar
Hirota K, Kubota T, Ishihara H, Matsuki A. The effect of nitrous oxide and ketamine on the bispectral index and 95% spectral edge frequency during propofol–fentanyl anaesthesia. Eur J Anaesthesiol 1999; 16: 779–783.Google Scholar
Brocas E, Dupont H, Paugam-Burtz C et al. Bispectral index variations during tracheal suction in mechanically ventilated critically ill patients: effect of an alfentanil bolus. Intens Care Med 2002; 28: 211–213.Google Scholar