Effect of isoflurane on the auditory evoked response in man.

We have examined the effects of isoflurane (0.6-2.9% end-tidal) on the auditory evoked response (AER) in six patients before elective surgery. Isoflurane produced significant dose-related changes in the AER: reductions in amplitude and increases in latency of the cortical waves Pa and Nb, and increases in the latency of the brainstem waves III and V. When isoflurane was compared with halothane and enflurane using an MAC-based comparison, we found no differences in the effect of the three agents on the amplitude of the early cortical waves, although the latencies showed significant differences. The consistent dose-related effect on the amplitudes of the cortical waves implies that the AER could be a promising index of the depth of anaesthesia.

[1]  A. Lam,et al.  The Effects of Isoflurane and Isoflurane‐Nitrous Oxide Anesthesia on Brainstem Auditory Evoked Potentials in Humans , 1985, Anesthesia and analgesia.

[2]  Hughes Cc.  Lipid solubility, pharmacokinetics, and the EEG: are you better off today than you were four years ago? , 1985 .

[3]  C P Heneghan,et al.  Selective effect of althesin on the auditory evoked response in man. , 1986, British journal of anaesthesia.

[4]  T. A. Ryan,et al.  Minitab Student Handbook , 1979 .

[5]  M. Reivich,et al.  Local Cerebral Glucose Uptake in Awake and Halothane‐anesthetized Primates , 1978, Anesthesiology.

[6]  J. Sear,et al.  Plasma concentrations of alphaxalone during continuous infusion of Althesin. , 1979, British Journal of Anaesthesia.

[7]  C P Heneghan,et al.  Effects of halothane or enflurane with controlled ventilation on auditory evoked potentials. , 1984, British journal of anaesthesia.

[8]  C. Thornton,et al.  Enflurane anaesthesia causes graded changes in the brainstem and early cortical auditory evoked response in man. , 1983, British journal of anaesthesia.

[9]  Louis Sokoloff,et al.  Potential Pitfalls in Measuring Regional Cerebral Glucose Utilization , 1983 .

[10]  L S Hibbard,et al.  Regional Cerebral Glucose Utilization during Althesin® Anesthesia , 1984, Anesthesiology.

[11]  L. Sokoloff,et al.  Localization of Functional Activity in the Central Nervous System by Measurement of Glucose Utilization with Radioactive Deoxyglucose , 1981, Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism.

[12]  C. Hug.  Lipid solubility, pharmacokinetics, and the EEG: are you better off today than you were four years ago? , 1985, Anesthesiology.

[13]  J. Whitby,et al.  AWARENESS DURING ANAESTHESIA , 1977 .

[14]  B. Rosner,et al.  Neurophysiologic Effects of General Anesthetics: I. The Electroencephalogram and Sensory Evoked Responses in Man , 1973, Anesthesiology.

[15]  K. Maurer,et al.  Detection and localization of brainstem lesions with auditory brainstem potentials , 1980 .