Electrophysiologic effects of propofol sedation.
The scalp electroencephalogram (EEG), the long latency cognitive P300 auditory evoked response (AER), and reaction times were recorded in 10 volunteers sedated with a computer-controlled infusion of propofol to target plasma concentrations of 0.3, 0.6, 0.9, and 1.2 micrograms/mL. The observed mean +/- SE venous plasma concentrations were 0.152 +/- 0.042, 0.372 +/- 0.078, 0.679 +/- 0.104, and 1.065 +/- 0.112 micrograms/mL, respectively. Scalp EEG topographic mapping revealed that beta 1 activation was primarily frontal and central with relative sparing of the temporal lobes. The P300 response was dramatically reduced by propofol in a concentration-dependent manner, even though the subjects were conscious but clearly sedated. Mean +/- SE reaction times were increased by propofol sedation from 347 +/- 35 ms (control) to 391 +/- 48, 460 +/- 70, 549 +/- 64, and 622 +/- 120 ms at increasing mean venous plasma propofol concentrations. The mean percentage +/- SE of correct responses decreased from 98.1 +/- 2.0 (control) to 99.1 +/- 1.7, 87.4 +/- 9.2, 82.8 +/- 12.9, and 69.8 +/- 20.9 at increasing propofol concentrations. Dramatic alterations in the EEG, P300 response, and reaction times were observed, especially with the higher plasma concentrations which produced conscious sedation.
Department of Anesthesiology, University of Michigan, Ann Arbor 48109-0630.
J R
JR
Sneyd
S K
SK
Samra
B
B
Davidson
T
T
Kishimoto
C
C
Kadoya
E F
EF
Domino
D000328:Adult; D001611:Beta Rhythm / Q000187:drug effects*; D016292:Procedural Sedation; D004305:Dose-Response Relationship, Drug; D004594:Electrophysiology; D005072:Evoked Potentials, Auditory / Q000187:drug effects*; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D015742:Propofol / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*
D015742:Propofol