The Narcotrend Index: classification algorithm, correlation with propofol effect-site concentrations, and comparison...

Area of Science:

• Anesthesiology
• Neuroscience
• Medical Devices

Background:

• Assessing hypnosis depth during anesthesia is crucial for patient safety.
• Current EEG monitoring methods have limitations in providing a reliable depth of hypnosis measure.

Purpose of the Study:

• To evaluate the Narcotrend Index's performance in assessing hypnosis depth.
• To compare the Narcotrend Index with traditional spectral EEG parameters and propofol effect-site concentration.

Main Methods:

• The Narcotrend Index, from the Narcotrend EEG monitor (version 4.0), was used for automatic EEG classification.
• Correlation analysis was performed between the Narcotrend Index and propofol effect-site concentration.
• Comparison with traditional spectral EEG parameters including total power, relative power (delta, theta, alpha, beta), median frequency, 95% spectral edge frequency, burst-compensated spectral edge frequency, and spectral entropy.

Main Results:

• The Narcotrend Index demonstrated the highest average correlation with propofol effect-site concentration.
• It exhibited the smallest variability in individual correlation values compared to other parameters.
• The Narcotrend Index was the sole parameter showing a consistent monophasic trend throughout the study period.

Conclusions:

• The Narcotrend Index provides a reliable measure of hypnosis depth during anesthesia.
• It offers superior correlation and consistency compared to traditional EEG spectral parameters.
• The Narcotrend monitor can enhance anesthesia quality by enabling individualized hypnotic drug titration.