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A comparison of the effects on bispectral index of mild vs. moderate hypothermia during cardiopulmonary bypass

Published online by Cambridge University Press:  14 February 2006

D. Honan ,
D. Doherty  and
H. Frizelle
D. Honan
Affiliation:
Mater Misericordiae University Hospital, Division of Anaesthesia, Dublin, Ireland
D. Doherty
Affiliation:
Mater Misericordiae University Hospital, Division of Anaesthesia, Dublin, Ireland
H. Frizelle
Affiliation:
Mater Misericordiae University Hospital, Division of Anaesthesia, Dublin, Ireland
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Abstract

Summary

Background and objective: Bispectral Index® correlates with depth of hypnosis in adult patients. Bispectral index monitoring has been separately examined and validated during both mild and moderate hypothermic cardiopulmonary bypass. However, the effect on bispectral index of these two differing cardiopulmonary bypass temperature regimes has not previously been compared, particularly with the use of volatile anaesthetic agents. Methods: Following Institutional Ethics Committee approval and informed consent, 30 patients undergoing coronary artery bypass grafting had additional bispectral index monitoring. Sixteen patients had mild hypothermic bypass (32–34°C), and 14 had moderate hypothermic bypass (28–30°C). Anaesthesia was standardized, and was maintained with enflurane throughout surgery. Scores were recorded at 14 specific event-related time points during surgery. Results: This study has demonstrated that in this adult population, a relationship exists between bispectral index score and temperature throughout the duration of cardiac surgery, which included mild or moderate hypothermic cardiopulmonary bypass. It also demonstrated that patients which were categorized as having received moderately hypothermic cardiopulmonary bypass had lower bispectral index scores than those patients who received mild hypothermic cardiopulmonary bypass, at time points corresponding approximately with median steady-state bypass temperature, pre-re-warming and early re-warming periods. Conclusions: Moderate hypothermic cardiopulmonary bypass has lower bispectral index scores when compared to mild hypothermic cardiopulmonary bypass, at a steady state of inspired enflurane. This may reflect an actual increase in the depth of hypnosis. However, as this study did not address the physico-chemical changes of the volatile agent or the accuracy of the bispectral index algorithm at lower temperatures, we would not advocate a change in practice based solely on this report.

Keywords

ELECTROENCEPHALOGRAPHY, Bispectral IndexCARDIOPULMONARY BYPASSHYPOTHERMIASURGERY, CARDIAC
Type
EACTA Original Article
Information
European Journal of Anaesthesiology , Volume 23 , Issue 5 , May 2006 , pp. 385 - 390
Copyright
2006 European Society of Anaesthesiology

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References

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.Google Scholar
Ranta SO, Herranen P, Hynynen M. Patients’ conscious recollections from cardiac anesthesia. J Cardiothorac Vasc Anesth 2002; 16: 426–430.Google Scholar
Rampil IJ. A primer for EEG signal processing in anesthesia. Anesthesiology 1998; 89: 980–1002.Google Scholar
Sebel PS. Central nervous system monitoring during open heart surgery: an update. J Cardiothorac Vasc Anesth 1998; 12 (2 Suppl 1): 3–8.Google Scholar
Doi M, Gajraj RJ, Mantzaridis H, Kenny GN. Effects of cardiopulmonary bypass and hypothermia on electroencephalographic variables. Anaesthesia 1997; 52: 1048–1055.Google Scholar
Barr G, Anderson RE, Samuelsson S, Owall A, Jakobsson JG. Fentanyl and midazolam anaesthesia for coronary bypass surgery: a clinical study of bispectral electroencephalogram analysis, drug concentrations and recall. Br J Anaesth 2000; 84: 749–752.Google Scholar
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.Google Scholar
Puri DG, Bagchi A, Anandamurthy B, Dhaliwal RS. The Bispectral Index and induced hypothermia – electrical silence: an unusually high temperature. Anaesth Intensive Care 2003; 31: 578–580.Google Scholar
Dewandre PY, Hans P, Bonhomme V, Brichant JF, Lamy M. Effects of mild hypothermic cardiopulmonary bypass on EEG bispectral index. Acta Anaesthesiol Belg 2000; 51: 187–190.Google Scholar
Hirschi M, Meistelman C, Longrois D. Effects of normothermic cardiopulmonary bypass on bispectral index. Eur J Anaesthesiol 2000; 17: 499–505.Google Scholar
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.Google Scholar
Glass PS, Bloom M, Kearse L, Rosow C, Sebel P, Manberg P. Bispectral analysis measures sedation and memory effects of propofol, midazolam, isoflurane, and alfentanil in healthy volunteers. Anesthesiology 1997; 86: 836–847.Google Scholar
Lockwood GG, Sapsed-Byrne SM, Smith MA. Effect of temperature on the solubility of desflurane, sevoflurane, enflurane and halothane in blood. Br J Anaesth 1997; 79: 517–520.Google Scholar
Zhou JX, Liu J. The effect of temperature on solubility of volatile anesthetics in human tissues. Anesth Analg 2001; 93: 234–238.Google Scholar
Targ AG, Yasuda N, Eger II EI. Solubility of I-653, sevoflurane, isoflurane, and halothane in plastics and rubber composing a conventional anesthetic circuit. Anesth Analg 1989; 69: 218–225.Google Scholar
Tarr TJ, Snowdon SL. Blood/gas solubility coefficient and blood concentration of enflurane during normothermic and hypothermic cardiopulmonary bypass. J Cardiothorac Vasc Anesth 1991; 5: 111–115.Google Scholar
Stecker MM, Cheung AT, Pochettino Aet al. Deep hypothermic circulatory arrest: I. Effects of cooling on electroencephalogram and evoked potentials. Ann Thorac Surg 2001; 71: 14–21.Google Scholar
Bashein G, Nessly ML, Bledsoe SWet al. Electroencephalography during surgery with cardiopulmonary bypass and hypothermia. Anesthesiology 1992; 76: 878–891.Google Scholar
Levy WJ, Pantin E, Mehta S, McGarvey M. Hypothermia and the approximate entropy of the electroencephalogram. Anesthesiology 2003; 98: 53–57.Google Scholar
Puri GD, Murthy SS. Bispectral index monitoring in patients undergoing cardiac surgery under cardiopulmonary bypass. Eur J Anaesthesiol 2003; 20: 451–456.Google Scholar
Laussen PC, Murphy JA, Zurakowski D, Sullivan LJ, McGowan JrFX, Demaso DR. Bispectral index monitoring in children undergoing mild hypothermic cardiopulmonary bypass. Paediatr Anaesth 2001; 11: 567–573.Google Scholar
Maruyama M, Okamoto H, Suwa J, Asou T, Hoka S. Bispectral index monitoring in fast track pediatric cardiac surgery. Masui 2004; 53: 629–633.Google Scholar
Bein B, Tonner PH. Bispectral index monitoring in patients undergoing cardiac surgery under cardiopulmonary bypass: the influence of temperature changes should be considered. Eur J Anaesthesiol 2004; 21: 330–333.Google Scholar
Zabala L, Ahmed MI, Denman WT. Bispectral index in a 3-year-old undergoing deep hypothermia and circulatory arrest. Paediatr Anaesth 2003; 13: 355–359.Google Scholar
Spain K. Use of deep hypothermic circulatory arrest following ventricular laceration: a case report. AANA J 2004; 72: 193–195.Google Scholar
Fay T, Smith GW. Observations on reflex responses during prolonged periods of human refridgeration. Arch Neuro Psychiat 1941; 45: 215.Google Scholar