Understanding EEG Patterns in Anesthesia
Electroencephalography (EEG) is a vital monitoring tool that measures electrical activity in the brain during anesthesia. Different anesthetic agents produce characteristic EEG patterns that can help clinicians assess the depth of anesthesia and avoid awareness during procedures.
Loading EEG visualization...
Interactive chart: Use the slider and controls below to navigate through the recording. Use keyboard arrow keys for precise navigation (Home/End to jump to start/end).
Processing spectral data...
Common EEG Patterns During Anesthesia
ⓘ Understanding EEG frequency bands
Different frequency bands in EEG correlate with different states of consciousness.
During anesthesia, there's typically a shift from high to low frequencies.
- Alpha Waves (8-12 Hz): Present during relaxed wakefulness
- Beta Waves (13-30 Hz): Associated with light anesthesia or sedation
- Delta Waves (0.5-4 Hz): Predominant in deep anesthesia
- Theta Waves (4-8 Hz): Often seen during drowsiness and light sleep
- Burst Suppression: Alternating periods of activity and electrical silence in deep anesthesia
Reading the EEG Spectrogram
The spectrogram above provides a powerful visual representation of EEG frequency content over time:
- Color intensity indicates power - brighter colors represent stronger signals at that frequency
- Vertical axis shows frequency (0-30 Hz) with lower frequencies at the bottom
- Horizontal axis represents time, matching the EEG time window above
- Horizontal lines mark the boundaries between clinical frequency bands (delta, theta, alpha, beta)
- During anesthesia, you'll typically see a shift from high-frequency (upper) to low-frequency (lower) power