Frontal EEG Temporal and Spectral Dynamics Similarity Analysis between Propofol and Desflurane Induced Anesthesia...

Area of Science:

• Neuroscience
• Anesthesiology
• Signal Processing

Background:

• Electroencephalogram (EEG) signal analysis is crucial for understanding brain dynamics and activity under different anesthetic agents.
• Gamma-amino butyric acid (type A -GABAA) dependent anesthetics like propofol and desflurane significantly impact brain activity, necessitating comparative analysis.

Purpose of the Study:

• To compare the EEG spectrogram dynamics under propofol and desflurane anesthesia.
• To evaluate the efficacy of Hilbert-Huang Transform (HHT) against Fourier-based methods for analyzing anesthetic-induced EEG changes.

Main Methods:

• EEG data from 28 patients receiving propofol and 23 patients receiving desflurane were analyzed.
• Hilbert-Huang Transform (HHT) was employed to compute time-varying spectral properties.
• Comparison of HHT with Fourier-based methods for analyzing band power, peak frequency, and frequency band differences.

Main Results:

• HHT demonstrated more concentrated power distribution in slow and alpha bands compared to Fourier methods during anesthetic-induced unconsciousness.
• HHT showed improved convergence for peak frequency in slow and theta bands and a shift to lower alpha band frequencies.
• Significant differences in high beta and delta band power were observed between propofol and desflurane when analyzed with HHT during unconsciousness.

Conclusions:

• EEG analysis reveals considerable differences between HHT and Fourier methods in characterizing brain activity under anesthesia.
• HHT provides a more refined spectral analysis of EEG signals, offering deeper insights into anesthetic effects.
• The study highlights distinct neural activity patterns associated with propofol and desflurane, particularly in high beta and delta bands, when analyzed with HHT.