Abstract
Objective. The aim of this study was to evaluate Bispectral Index values and awareness during two different anaesthesia regimens (fentanyl-propofol and fentanyl-midazolam) in patients undergoing off-pump CABG surgery. Methods. Fifty patients were included in the study. Patients were premedicated with midazolam and were randomly divided into two groups. Anaesthesia was induced with fentanyl (7–15 μg/kg), with either propofol (2–2.5 mg/kg, Group I) or midazolam (0.1–0.3 mg/kg, Group II) and vecuronium (0.1 mg/kg). Anaesthesia was maintained with fentanyl (15 μg/kg/h) together with either propofol (6 mg/kg/h) or midazolam (0.1 mg/kg/h). Depth of anaesthesia was adjusted according to clinical signs and haemodynamic responses. The level of sedation was monitored with Bispectral index continuously, but these levels were not shown to the attending anaesthetist. Bispectral index values were recorded for nine phases. Twenty-four hours after the operation, the patients were interviewed to determine intraoperative awareness and recall. Results. In all patients, Bispectral index values were found to decrease after induction (in Group I, p = 0.005, in Group II, p = 0.008) with the mean values remaining below 60 for all phases. The differences between the groups were not statistically significant in inter-group comparison. No patients were noted to recall the sounds presented during the operation and the preoperative events. Conclusions. BIS monitoring with clinical signs may be used to assess the adequacy of both types of anaesthesia techniques as well as to detect awareness during off-pump CABG surgery.
Similar content being viewed by others
References
Schwender D, Kunze-Kronawitter H, Dietrich P, Klasing S, Forst H, Madler C. Conscious awareness during general anaesthesia: Patients’ perceptions, emotions, cognition and reactions. Br J Anaesth 1998; 80: 133–139.
Ghoneim MM. Awareness during anesthesia. Anesthesiology 2000; 92: 597–602.
Dowd NP, Cheng DCH, Karski JM, Wong DT, Carroll Munro JA, Sandler AN. Intraoperative awareness in fast-track cardiac anesthesia. Anesthesiology 1998; 89: 1068–1073.
Ranta SO, Herranen P, Hynynen M. Patients’ conscious recollections from cardiac anesthesia. J Cardiothorac Vasc Anesth 2002; 16: 426–430.
Phillips AA, McLean RF, Devitt JH, Harrington EM. Recall of intraoperative events after general anaesthesia and cardiopulmonary bypass. Can J Anaesth 1993; 40: 922–926.
Ranta S, Jussila J, Hynynen M. Recall of awareness during cardiac anaesthesia: Influence of feedback information to the anaesthesiologist. Acta Anaesth Scand 1996; 40: 54–560.
Johansen JW, Sebel PS. Development and clinical application of electroencephalographic bispectrum monitoring. Anesthesiology 2000; 93: 1336–1344.
Drummond JC. Monitoring depth of anesthesia (With emphasis on the application of the Bispectral. Index and the Middle Latency Auditory Evoked Response to the prevention of recall). Anesthesiology 2000; 93: 876–882.
Sebel PS. Central nervous system moniyoring during open heart surgery: An update. J Cardiothorac Vasc Anesth 1998; 12: 3–8.
Heames RM, Gill RS, Ohri SK, Hett DA. Off-pump coronary artery surgery. Anaesthesia 2002; 57: 676–685.
Schmidlin D, Hager P, Schmid ER. Monitoring level of sedation with bispectral EEG analysis: Comparison between hypothermic and normothermic cardiopulmonary bypass. Br J Anaesth 2001; 86: 769–776.
Barr G, Anderson RE, Samuelsson S, Öwall A, Jakobsson JG. Fentanyl and midazolam anaesthesia for coronary bypass surgery: A clnical study of bispectral electroenephalogram analysis, drug concentrations and recall. Br J Anaesth 2000; 84: 749–752.
Kubota T, Hirota K, Yoshida H, Yatsu Y, Maeda A, Matsuki A. Haemodynamic comparison of propofol-fentanyl anaesthesia with midazolam-fentanyl anaesthesia in CABG patients without preoperative heart failure. Acta Anaesth Belg 2000; 51: 197–200.
Oddby-Muhrbeck E, Jakobsson J. Recall of music: A comparison between anaesthesia with propofol and isoflurane. Acta Anaesthesiol Scand 1993; 37: 33–37.
Lehmann A, Zeitler C, Thaler E, Isgro F, Boldt J. Comparison of two different anesthesia regimens in patients undergoing aortocoronary bypass grafting surgery: Sufentanil-midazolam versus remifentanil-propofol. J Cardiothorac Vasc Anesth 2000; 14: 416–420.
Djaiani GN, Ali M, Heinrich L, et al. Ultra-fast-track anesthetic technique facilitates operating room extubation in patients undergoing off-pump coronary revascularization surgery. J Cardiothorac Vasc Anesth 2001; 15: 152–157.
Sebel PS, Bovill JG, Boekhorst RA, Rog N. Cardiovascular effects of high-dose fentanyl anaesthesia. Acta Anaesth Scand 1982; 26: 308–315.
Mathew JP, Weatherwax KJ, East CJ, White WD, Reves JG. Bispectral analysis during cardiopulmonary bypass: The effect of hypothermia on the hypnotic state. J Clin Anesth 2001; 13: 301–305.
Glass P, Bloom M, Kearse L, Rosow C, Sebel P, Manberg P. Bispectral analysis measures sedation and memory effects of propofol, midazolam, isoflurane, and alfentanyl in healthy volunteers. Anesthesiology 1997; 86: 836–847.
Kuizenga K, Wierda JMKH, Kalkman JC. Biphasic EEG changes in relation to loss of consciousness during induction with thiopental, propofol, etomidate, mdazolam or sevoflurane. Br J Anaesth 2001; 86: 354–360.
Hirschi M, Meistelman C, Longrois D. Effects of normothermic cardiopulmonary bypass on bispectral index. Eur J Anaesthesiol 2000; 17: 499–505.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Bestas, A., Yasar, M.A., Bayar, M.K. et al. The Effects of Two Different Anaesthesia Techniques on Bispectral Index Values and Awareness During Off-Pump Coronary Artery Bypass Grafting. J Clin Monit Comput 18, 347–351 (2004). https://doi.org/10.1007/s10877-005-7320-9
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/s10877-005-7320-9