Recording the middle latency auditory evoked potential as a measure of depth of anaesthesia. A technical note

Institute of Sound and Vibration Research, University of Southampton, Highfield, Southampton SO17 1BJ, UK.
BJA British Journal of Anaesthesia (Impact Factor: 4.85). 04/2004; 92(3):442-5. DOI: 10.1093/bja/aeh074
Source: PubMed


The middle latency response of the auditory evoked potential may be useful as an indicator of the hypnotic state during anaesthesia.
However, it is difficult to record in some circumstances. This communication provides some suggestions and guidance for those
not familiar with the technique.

Br J Anaesth 2004; 92: 442–5

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    • "All participants had normal hearing, with mean hearing thresholds below 25 dB hearing level, as assessed by pure-tone audiometry (with frequencies: 250, 500, 1000, 3000 and 8000 Hz) at the start of the experiment. Three participants were excluded from the statistical analysis as their MLR was contaminated by a postauricular muscle (PAM) response (Bell et al., 2004). The study was approved by the Ethical Committee of the University of Barcelona, and was in accordance with the Code of Ethics of the World Medical Association (Declaration of Helsinki ). "
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