BACKGROUND: The precise neural mechanisms of @entity1875 anesthesia in @entity1 are still unknown. The authors examined the acute effects of @entity1875 on regional cerebral blood flow (rCBF) using positron emission tomography in @entity1 with severe @entity308 . METHODS: In six severely @entity308 @entity1 (mean age, 55.0 yr) scheduled for electroconvulsive therapy, anesthetic levels were monitored by electroencephalography, and rCBF was serially quantified in the awake, sedated, and anesthetized states. The authors used high-resolution positron emission tomography with @entity8493 -labeled water and statistical parametric mapping 99 for imaging and analysis of the data. RESULTS: Global cerebral blood flow showed sharp decreases from the awake level during the administration of @entity1875 , decreasing 26.8% in the sedated state and 54.4% in the anesthetized state. Moreover, a dose effect was seen in both parietal cortices and the left lateral prefrontal region with larger regions of relative decrease in rCBF at higher @entity1875 doses. At the higher dose, the values of rCBF in the pulvinar nucleus of the thalamus, the pontine tegmentum, and the cerebellar cortex were also affected. Meanwhile, there were few changes of relative rCBF in the basal frontal lobes during both sedated and anesthetized states. CONCLUSIONS: As in earlier studies using normal subjects, pronounced suppression in rCBF in the brain stem reticular formation, the thalamus, and the parietal association cortex occurred even in severely @entity308 @entity1 . However, previously reported decreases in rCBF in the basal frontal lobe were absent in @entity308 @entity1 .

Neural mechanism of XXXX anesthesia in severe @entity308 : a positron emission tomographic study.

@entity1 :: ('9606', 'Species') :: ['humans', 'patients'] @entity8493 :: ('CHEBI:36932', 'Chemical') :: ['15O'] @entity308 :: ('MESH:D003866', 'Disease') :: ['depressed', 'depression'] @entity1875 :: ('MESH:D015742', 'Chemical') :: ['propofol']
@entity1875 :: (MESH:D015742,Chemical) :: ['propofol']
