Abstract
Purpose
During clinical monitoring, vecuronium appeared to reduce the rapidly extracted auditory evoked potentials index (A-line ARX index or AAI) to some extent. A prospective and randomized study was designed to analyze this phenomenon.
Methods
Forty adult patients undergoing elective surgery were studied. After tracheal intubation, anesthesia was maintained with an end-tidal isoflurane concentration (FETISO) of 1.0% for 20 min, then a 10-mL dose of either vecuronium 0.05 mg·kg−1, 0.1 mg·kg−1, 0.2 mg·kg−1 or saline was administered in a randomized, double-blind design. The AAI and bispectral index (Blhx) were monitored throughout the study and analyzed off-line.
Results
Blhx was unaltered after the administration of saline or vecuronium. The mean of the averaged (per patient) AAI values recorded from two minutes to ten minutes after the administration of saline or vecuronium 0.05 mg·kg−1 did not differ significantly from the corresponding mean recorded from 15 min to 20 min after FETISO maintained 1.0% (P = 0.678, 0.169), however after the administration of vecuronium 0.1 mg·kg−1 or 0.2 mg·kg−1, AAI was reduced from 18.3, 18.0 to 14.8, 13.4 (P = 0.016, 0.017).
Conclusions
Neuromuscular block with vecuronium reduces AAI in patients during steady state anesthesia without surgical stimuli, while Blhx is unaltered. The cut-off values of AAI for events should be determined according to the level of neuromuscular blockade when monitoring the depth of anesthesia/sedation.
Résumé
Objectif
Pendant le monitorage clinique, le vécuronium a semblé réduire, jusqu’à un certain point, l’index des potentiels évoqués d’extraction rapide (A-line ARX index ou AAI). Nous avons voulu analyser ce phénomène par une étude prospective et randomisée.
Méthode
Quarante patients adultes devant subir une opération réglée ont participé à l’étude. Après l’intubation endotrachéale, l’anesthésie a été maintenue avec une concentration d’isoflurane téléexpiratoire (FETISO) de 1,0% pendant 20 min, puis une dose de 10 mL de vécuronium, à 0,05 mg·kg−1, 0,1 mg·kg−1 ou 0,2 mg·kg−1, ou de soluté physiologique, a été administrée de façon randomisée et en double aveugle. L’AAI et l’index bispectral (Bihx) ont été enregistrés tout au long de l’étude et analysé en différé.
Résultats
Le Bihx n’était pas modifié après l’administration de solution saline ou de vécuronium. La moyenne des valeurs centrales d’AAI (par patient), notée de deux à dix minutes après l’administration de solution salée ou de 0,05 mg·kg−1 de vécuronium, ne différait pas de façon significative de la moyenne correspondante notée de 15 à 20 min après le maintien de la FETISO à 1,0 % (P = 0,678; 0,169), même si après l’administration de 0,1 mg·kg−1 ou de 0,2 mg·kg−1, l’AAI a été réduit de 18,3, 18,0 à 14,8, 13,4 (P = 0,016, 0,017).
Conclusion
Le bloc neuromusculaire avec du vécuronium réduit l’AAI pendant l’anesthésie en état d’équilibre sans stimuli chirurgical, mais le Bihx n’est pas modifié. Les valeurs seuil de l’AAI des événements chirurgicaux doivent être déterminées selon le niveau de bloc neuromusculaire pendant le monitorage de la profondeur de l’anesthésie/sédation.
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References
Jensen EW, Lindholm P, Henneberg SW. Autoregressive modeling with exogenous input of middle-latency auditory-evoked potentials to measure rapid changes in depth of anesthesia. Methods Inf Med 1996; 35: 256–60.
Struys MM, Jensen EW, Smith W, et al. Performance of the ARX-derived auditory evoked potential index as an indicator of anesthetic depth. A comparison with bispectral index and hemodynamic measures during propofol administration. Anesthesiology 2002; 96: 803–16.
Urhonen E, Jensen EW, Lund J. Changes in rapidly extracted auditory evoked potentials during tracheal intubation. Acta Anaesthesiol Scand 2000; 44: 743–8.
Alpiger S, Helbo-Hansen HS, Jensen EW. Effect of sevoflurane on the mid-latency auditory evoked potentials measured by a new fast extracting monitor. Acta Anaesthesiol Scand 2002; 46: 252–6.
Litvan H, Jensen EW, Revuelta M, et al. Comparison of auditory evoked potentials and the A-line ARX index for monitoring the hypnotic level during sevoflurane and propofol induction. Acta Anaesthesiol Scand 2002; 46: 245–51.
Litvan H, Jensen EW, Galan J, et al. Comparison of conventional averaged and rapid averaged,autoregressive-based extracted auditory evoked potentials for monitoring the hypnotic level during propofol induction. Anesthesiology 2002; 97: 351–8.
Ge SJ Zhuang XL, Wang YT, Wang ZD, Li HT. Changes in the rapidly extracted auditory evoked potentials index and the bispectral index during sedation induced by propofol or midazolam under epidural block. Br J Anaesth 2002; 89: 260–4.
Richmond CE, Matson A, Thornton C, Dore CJ, Newton DE. Effect of neuromuscular block on depth of anaesthesia as measured by the auditory evoked response. Br J Anaesth 1996; 76: 446–8.
Greif R, Greenwald S, Schweitzer E, et al. Muscle relaxation does not alter hypnotic level during propofol anesthesia. Anesth Analg 2002; 94: 604–8.
Stanski DR. Monitoring depth of anesthesia.In: Miller RD (Ed.). Anesthesia, 5th ed. Beijing: Science Press; 2001: 1087–116.
Lanier WL, Iaizzo PA, Milde JH, Sharbrough EW. The cerebral and systemic effects of movement in response to a noxious stimulus in lightly anesthetized dogs. Possible modulation of cerebral function by muscle afferents. Anesthesiology 1994; 80: 392–401.
Thornton C, Sharpe RM. Evoked responses in anaesthesia. Br J Anaesth 1998; 81: 771–81.
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This work was attributed to the Department of Anesthesiology, Shanghai First People’s Hospital.
Financial support was received from the Department of Anesthesiology, Shanghai First People’s Hospital.
There are no commercial or non-commercial affiliations that are or may be perceived to be a conflict of interest with this work.
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Ge, SJ., Zhuang, XL., He, RH. et al. Neuromuscular block with vecuronium reduces the rapidly extracted auditory evoked potentials index during steady state anesthesia. Can J Anesth 50, 1017–1022 (2003). https://doi.org/10.1007/BF03018365
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DOI: https://doi.org/10.1007/BF03018365