Effect of sub-anaesthetic infusions of propofol on peak velocity of saccadic eye movements.
Peak velocity of saccadic eye movements was studied in six healthy volunteers who received either 0.9% sodium chloride (as a control) or a stepwise rising propofol infusion regime of 0.24, 0.6 and 1.5 mg kg-1 h-1, which produced arterialized venous concentrations equivalent to 1%, 6% and 13% of the estimated EC50 for propofol. The infusion lasted for 75 min (25 min at each infusion rate) and was followed by a 2-h post-infusion recovery period. Peak saccadic velocity was highly significantly depressed during the 15-25-min period after the start of the second and third propofol infusions compared with saline. The relationship between arterialized venous blood concentration and peak saccadic velocity was similar during recovery when concentrations were falling to that during increasing blood propofol concentrations. Peak saccadic velocity decreased linearly with increasing log10 propofol concentration in the range of 25-800 ng ml-1 (14% of control per decade). Measured arterialized venous-blood propofol concentrations were variable, and systematically greater than computer predictions at the two higher infusion rates. In only half the subjects were the subjective assessments significantly correlated with log10 propofol concentrations or with percentage reduction in peak saccadic velocity.
Gao
F
F
Department of Anaesthetics, University of Wales College of Medicine, Heath Park, Cardiff, United Kingdom.
Mapleson
W W
WW
Vickers
M D
MD
D000328:Adult; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D015742:Propofol / Q000008:administration & dosage / Q000494:pharmacology*; D012016:Reference Values; D012438:Saccades / Q000187:drug effects* / Q000502:physiology
D015742:Propofol