Monitoring Depth of Hypnosis under Propofol General Anaesthesia - Granger Causality and Hidden Markov Models

Nicoletta Nicolaou, Julius Georgiou

Abstract

Intra-operative awareness is experienced when a patient regains consciousness during surgery. This work presents a Brain-Computer Interface system that can be used as part of routine surgery for monitoring the patient state of hypnosis in order to prevent intra-operative awareness. The underlying state of hypnosis is estimated using causality-based features extracted from the spontaneous electrical brain activity (EEG) of the patient and a probabilistic classification framework (Hidden Markov Models). The proposed method is applied to EEG activity from 20 patients under propofol anaesthesia. The mean discrimination performance obtained was 98% and 85% for wakefulness and anaesthesia respectively, with an overall performance accuracy of 92%. The use of a probabilistic framework increases the anaesthetist’s confidence on the estimated state of hypnosis based on the marginal probabilities of the underlying state.

References

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Paper Citation


in Harvard Style

Nicolaou N. and Georgiou J. (2013). Monitoring Depth of Hypnosis under Propofol General Anaesthesia - Granger Causality and Hidden Markov Models . In Proceedings of the International Congress on Neurotechnology, Electronics and Informatics - Volume 1: BrainRehab, (NEUROTECHNIX 2013) ISBN 978-989-8565-80-8, pages 256-261. DOI: 10.5220/0004679402560261


in Bibtex Style

@conference{brainrehab13,
author={Nicoletta Nicolaou and Julius Georgiou},
title={Monitoring Depth of Hypnosis under Propofol General Anaesthesia - Granger Causality and Hidden Markov Models},
booktitle={Proceedings of the International Congress on Neurotechnology, Electronics and Informatics - Volume 1: BrainRehab, (NEUROTECHNIX 2013)},
year={2013},
pages={256-261},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0004679402560261},
isbn={978-989-8565-80-8},
}


in EndNote Style

TY - CONF
JO - Proceedings of the International Congress on Neurotechnology, Electronics and Informatics - Volume 1: BrainRehab, (NEUROTECHNIX 2013)
TI - Monitoring Depth of Hypnosis under Propofol General Anaesthesia - Granger Causality and Hidden Markov Models
SN - 978-989-8565-80-8
AU - Nicolaou N.
AU - Georgiou J.
PY - 2013
SP - 256
EP - 261
DO - 10.5220/0004679402560261