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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    • "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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    • "However, most drugs used for anaesthesia have effects on blood brain pressure, which is already high when a brain tumor grows, or are known to be radioprotective for the normal brain parenchyma. Ketamine, which is commonly used for anaesthesia of rodents, induces a general increase in cerebral blood flow at anaesthetic concentrations [15]. Some authors reported that pentobarbital protects against radiation-induced damage to normal rat brain. "
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