Pierre Fiset

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In the present study, we investigated changes in regional cerebral blood flow (rCBF) in humans during the progression from relaxed wakefulness through slow wave sleep (SWS). These changes were examined as a function of spindle (12-15 Hz) and delta (1.5-4.0 Hz) electroencephalographic (EEG) activity of SWS. rCBF was studied with positron emission tomography(More)
In the present study, we used positron emission tomography to investigate changes in regional cerebral blood flow (rCBF) during a general anesthetic infusion set to produce a gradual transition from the awake state to unconsciousness. Five right-handed human volunteers participated in the study. They were given propofol with a computer-controlled infusion(More)
BACKGROUND Remifentanil (GI87084B) is a new short-acting opioid with a unique ester structure. Metabolism of remifentanil by ester hydrolysis results in very rapid elimination. The aim of this study was to characterize in detail the pharmacokinetic profile of remifentanil in healthy male volunteers. METHODS Ten healthy adult male volunteers received a(More)
We investigated the effects of the general anesthetic agent propofol on cerebral structures involved in the processing of vibrotactile information. Using positron emission tomography (PET) and the H(2)(15)O bolus technique, we measured regional distribution of cerebral blood flow (CBF) in eight healthy human volunteers. They were scanned under five(More)
BACKGROUND The extent to which complex auditory stimuli are processed and differentiated during general anesthesia is unknown. The authors used blood oxygenation level-dependent functional magnetic resonance imaging to examine the processing words (10 per period; compared with scrambled words) and nonspeech human vocal sounds (10 per period; compared with(More)
The aim of this study was to assess dynamic changes in protein and glucose metabolism during surgery. Twelve patients undergoing colorectal surgery received either intravenous propofol anesthesia (n = 6) or inhalational anesthesia with desflurane (n = 6). Pre- and intraoperative protein and glucose kinetics were analyzed by an isotope dilution technique(More)
BACKGROUND Functional brain imaging offers a way to investigate how general anaesthetics impair consciousness. However, functional imaging changes may result from drug effects unrelated to hypnosis. Establishing a causal link with loss of consciousness is thus difficult. METHODS To identify changes of neuronal activity functionally linked to the level of(More)
BACKGROUND Anatomic and physiologic data show that multiple regions of the forebrain are activated by pain. However, the effect of anesthetic level on nociceptive input to these regions is not well understood. METHODS The authors used positron emission tomography to measure the effect of various concentrations of propofol on pain-evoked changes in(More)
The main objective of this investigation was to test the hypothesis that brain serotonin (5-HT) synthesis, as measured by trapping of alpha-[(11)C]methyl-L-tryptophan (alpha-MTrp) using positron emission tomography (PET), can be modulated by changes in blood oxygen. The study involved six healthy participants (three male and three female), who breathed a(More)