Comparative effects of dexmedetomidine, propofol, sevoflurane, and S-ketamine on regional cerebral glucose metabolism in humans: a positron emission tomography studyShow others and affiliations
2018 (English)In: British Journal of Anaesthesia, ISSN 0007-0912, E-ISSN 1471-6771, Vol. 121, no 1, p. 281-290Article in journal (Refereed) Published
Abstract [en]
IntroductionThe highly selective α2-agonist dexmedetomidine has become a popular sedative for neurointensive care patients. However, earlier studies have raised concern that dexmedetomidine might reduce cerebral blood flow without a concomitant decrease in metabolism. Here, we compared the effects of dexmedetomidine on the regional cerebral metabolic rate of glucose (CMRglu) with three commonly used anaesthetic drugs at equi-sedative doses.
MethodsOne hundred and sixty healthy male subjects were randomised to EC50 for verbal command of dexmedetomidine (1.5 ng ml−1; n=40), propofol (1.7 μg ml−1; n=40), sevoflurane (0.9% end-tidal; n=40) or S-ketamine (0.75 μg ml−1; n=20) or placebo (n=20). Anaesthetics were administered using target-controlled infusion or vapouriser with end-tidal monitoring. 18F-labelled fluorodeoxyglucose was administered 20 min after commencement of anaesthetic administration, and high-resolution positron emission tomography with arterial blood activity samples was used to quantify absolute CMRglu for whole brain and 15 brain regions.
ResultsAt the time of [F18]fluorodeoxyglucose injection, 55% of dexmedetomidine, 45% of propofol, 85% of sevoflurane, 45% of S-ketamine, and 0% of placebo subjects were unresponsive. Whole brain CMRglu was 63%, 71%, 71%, and 96% of placebo in the dexmedetomidine, propofol, sevoflurane, and S-ketamine groups, respectively (P<0.001 between the groups). The lowest CMRglu was observed in nearly all brain regions with dexmedetomidine (P<0.05 compared with all other groups). With S-ketamine, CMRgludid not differ from placebo.
ConclusionsAt equi-sedative doses in humans, potency in reducing CMRglu was dexmedetomidine>propofol>ketamine=placebo. These findings alleviate concerns for dexmedetomidine-induced vasoconstriction and cerebral ischaemia.
Place, publisher, year, edition, pages
Elsevier, 2018. Vol. 121, no 1, p. 281-290
National Category
Other Medical Sciences not elsewhere specified
Research subject
Consciousness and Cognitive Neuroscience
Identifiers
URN: urn:nbn:se:his:diva-15615DOI: 10.1016/j.bja.2018.04.008ISI: 000439025500072PubMedID: 29935583Scopus ID: 2-s2.0-85046622088OAI: oai:DiVA.org:his-15615DiVA, id: diva2:1219082
Conference
10th International Symposium on Memory and Awareness in Anesthesia (MAA), Helsinki, Finland, June 19-21, 2017
Note
CC BY-NC-ND 4.0
2018-06-152018-06-152020-11-02Bibliographically approved