Postoperative Delirium Severity and Recovery Correlate With Electroencephalogram Spectral Features

Area of Science:

• Neuroscience
• Geriatric Medicine
• Anesthesiology

Background:

• Delirium is an acute brain syndrome with no reliable biomarker.
• Electroencephalogram (EEG) oscillations may serve as a potential biomarker for delirium.
• This study investigates EEG frequencies in relation to postoperative delirium.

Purpose of the Study:

• To evaluate the association between EEG oscillation frequencies and delirium onset, severity, and recovery.
• To determine if EEG can serve as a biomarker for postoperative delirium.
• To explore the relationship between specific EEG spectral features and core delirium symptoms.

Main Methods:

• Longitudinal EEG recordings from 26 adults undergoing major surgery.
• Analysis of relative power in delta, theta, and alpha bands during eyes-open and eyes-closed states.
• Mixed-effects models used to assess delirium severity and EEG power relationships, and EEG power over time.

Main Results:

• Occipital alpha power inversely correlated with delirium severity and inattention.
• Occipital theta power positively correlated with delirium severity, inattention, and disorganized thinking.
• Frontal theta power correlated with altered consciousness and decreased over time post-surgery.

Conclusions:

• Postoperative delirium presence, severity, and core features correlate with EEG spectral features.
• EEG offers a cost-effective and accessible tool for delirium research.
• Findings support EEG's potential for future mechanistic and interventional delirium trials.