Effects of Xenon Anesthesia on Cerebral Blood Flow in Humans

University of Turku, Turku, Varsinais-Suomi, Finland
Anesthesiology (Impact Factor: 5.88). 06/2007; 106(6):1128-33. DOI: 10.1097/01.anes.0000267596.57497.92
Source: PubMed


Animal studies have demonstrated a strong neuroprotective property of xenon. Its usefulness in patients with cerebral pathology could be compromised by deleterious effects on regional cerebral blood flow (rCBF).
15O-labeled water was used to determine rCBF in nine healthy male subjects at baseline and during 1 minimum alveolar concentration (MAC) of xenon (63%). Anesthesia was based solely on xenon. Absolute changes in rCBF were quantified using region-of-interest analysis and voxel-based analysis.
Mean arterial blood pressure and arterial partial pressure for carbon dioxide remained unchanged. The mean (+/-SD) xenon concentration during anesthesia was 65.2+/-2.3%. Xenon anesthesia decreased absolute rCBF by 34.7+/-9.8% in the cerebellum (P<0.001), by 22.8+/-10.4% in the thalamus (P=0.001), and by 16.2+/-6.2% in the parietal cortex (P<0.001). On average, xenon anesthesia decreased absolute rCBF by 11.2+/-8.6% in the gray matter (P=0.008). A 22.1+/-13.6% increase in rCBF was detected in the white matter (P=0.001). Whole-brain voxel-based analysis revealed widespread cortical reductions and increases in rCBF in the precentral and postcentral gyri.
One MAC of xenon decreased rCBF in several areas studied. The greatest decreases were detected in the cerebellum, the thalamus and the cortical areas. Increases in rCBF were observed in the white matter and in the pre- and postcentral gyri. These results are in clear contradiction with ketamine, another N-methyl-D-aspartate antagonist and neuroprotectant, which induces a general increase in cerebral blood flow at anesthetic concentrations.

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    • "We observed a departure from slow and temporally correlated dynamics in frontal regions and in the thalamus. These areas strongly overlap with those where decreased metabolism under anesthesia was reported (Alkire et al., 1997; Kaisti et al., 2002; Kaisti et al., 2003; Schreckenberger et al., 2004; Laitio et al., 2007; Bonhomme et al., 2008). Breakdown of longrange temporal correlations was also reported in other unconscious brain states such as deep non-rapid eye movement (NREM) sleep (Tagliazucchi et al., 2013a). "
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    • "A recent study by Laitio et. al. [35] showed that administration of xenon (63%) in humans decreased rCBF in the cerebellum, thalamus, and cortical areas, while increasing rCBF in white matter and in parts of the precentral and postcentral gyri. Based on work by Rex et. "
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    • "In rat brain synaptic plasma membranes, xenon inhibits plasma membrane calcium ATPase pump activity, resulting in an increase in neuronal Ca2+ concentration and an altered excitability in these cells [156]. The decrease in regional CBF after xenon treatment [157] may help reduce intracranial pressure, and the regional cerebral metabolic rate for glucose [158]. "
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