EEG; Index; Medical Systems; Systems; analyzed; anesthesiologists; anesthetized; capitalize; cells; changed; claimed; company; complex; consciousness; data; depth; developing; devices; discovered; electrical; emitted; end-tidal; entered; exhibited; finding; gauge; heart; high-frequency; hypnotic; lost; low-frequency; measure; measuring; methods; monitoring; nerve; oximetry; patients; provided; pulse; reacting; relied; researchers; signals; signals.Aspect; true; variety; waves... show all keywordsEEG; Index; Medical Systems; Systems; analyzed; anesthesiologists; anesthetized; capitalize; cells; changed; claimed; company; complex; consciousness; data; depth; developing; devices; discovered; electrical; emitted; end-tidal; entered; exhibited; finding; gauge; heart; high-frequency; hypnotic; lost; low-frequency; measure; measuring; methods; monitoring; nerve; oximetry; patients; provided; pulse; reacting; relied; researchers; signals; signals.Aspect; true; variety; waves
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For years, anesthesiologists relied on a variety of methods to gauge how patients were reacting to anesthesia, such as measuring heart rate, pulse oximetry and end-tidal CO2. Then researchers discovered that anesthetized patients exhibited changes in the electrical signals emitted by the nerve cells in the brain. As patients lost consciousness and entered a hypnotic state, their EEG waves changed from low-amplitude, high-frequency signals to large-amplitude, low-frequency signals.
