ArticleAnesthesiology2017
Neurophysiologic Correlates of Ketamine Sedation and Anesthesia: A High-density Electroencephalography Study in Healthy Volunteers.
Article in Anesthesiology, 2017. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 55 papers, 1 of them a synthesis that pooled it.
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Who cites it
55 citing papers in PubMed, 1 synthesis or guideline pooled it, 124 citations in OpenAlex.
- A methodological guideline for consciousness assessment via neural electrophysiological activity.Military Medical Research · 2025Guideline
- Opioid-Free Anesthesia Improved the Quality of Recovery After Thyroidectomy Through Pre-Emptive and Preventive Analgesia: A Randomized Controlled Trial.Drug design, development and therapy · 2025Trial
- The effect of low-dose ketamine on electroencephalographic spectrum during gynecology surgery under desflurane anesthesia.Journal of the Chinese Medical Association : JCMA · 2024Trial
- Effects of intra-operative administration of subanesthetic s-ketamine on emergence from sevoflurane anesthesia: a randomized double-blind placebo-controlled study.BMC anesthesiology · 2023Trial
- Trial
- Study on EEG neural oscillation characteristics during ciprofol general anesthesia.Journal of anesthesia · 2026Observational
- Catecholamine modulation of frontal cortical ignition during wakefulness, sleep and anesthesia.National science review · 2026Article
- Monitoring the Depth of Sedation During Gastrointestinal Endoscopy: A Narrative Review of Current Evidence and Clinical Recommendations.Diagnostics (Basel, Switzerland) · 2026Review
- Neural Circuit Mechanisms of General Anaesthesia Induction: Current Advances and Future Directions.Current neuropharmacology · 2026Review
- Illuminating consciousness.Frontiers in psychology · 2026Review
- Windows to Consciousness: The Role of Fronto-Parietal Connectivity in Anesthesia-Induced Unconsciousness.Current neuropharmacology · 2026Review
- Article
- Neurophysiological correlates of ketamine-induced dissociative state in bipolar disorder: insights from real-world clinical settings.Molecular psychiatry · 2025Article
- Ketamine in clinical practice: transitioning from anesthetic agent to psychiatric therapeutic.CNS spectrums · 2025Review
- A neuroscientific model of near-death experiences.Nature reviews. Neurology · 2025Review
- Convergent effects of different anesthetics on changes in phase alignment of cortical oscillations.Cell reports · 2025Article
- The Administration of Ketamine Is Associated with Dose-Dependent Stabilization of Cortical Dynamics in Humans.The Journal of neuroscience : the official journal of the Society for Neuroscience · 2025Article
- Electroencephalogram monitoring during anesthesia and critical care: a guide for the clinician.Journal of clinical monitoring and computing · 2025Review
- Connectome harmonic decomposition tracks the presence of disconnected consciousness during ketamine-induced unresponsiveness.British journal of anaesthesia · 2025Article
- Consciousness and the Dying Brain.Anesthesiology · 2024Review
Corrections and comments
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Authors and funding
12 authors at 2 institutions in 1 country.
Funding
Abstract
backgroundPrevious studies have demonstrated inconsistent neurophysiologic effects of ketamine, although discrepant findings might relate to differences in doses studied, brain regions analyzed, coadministration of other anesthetic medications, and resolution of the electroencephalograph. The objective of this study was to characterize the dose-dependent effects of ketamine on cortical oscillations and functional connectivity.
methodsTen healthy human volunteers were recruited for study participation. The data were recorded using a 128-channel electroencephalograph during baseline consciousness, subanesthetic dosing (0.5 mg/kg over 40 min), anesthetic dosing (1.5 mg/kg bolus), and recovery. No other sedative or anesthetic medications were administered. Spectrograms, topomaps, and functional connectivity (weighted and directed phase lag index) were computed and analyzed.
resultsFrontal theta bandwidth power increased most dramatically during ketamine anesthesia (mean power ± SD, 4.25 ± 1.90 dB) compared to the baseline (0.64 ± 0.28 dB), subanesthetic (0.60 ± 0.30 dB), and recovery (0.68 ± 0.41 dB) states; P < 0.001. Gamma power also increased during ketamine anesthesia. Weighted phase lag index demonstrated theta phase locking within anterior regions (0.2349 ± 0.1170, P < 0.001) and between anterior and posterior regions (0.2159 ± 0.1538, P < 0.01) during ketamine anesthesia. Alpha power gradually decreased with subanesthetic ketamine, and anterior-to-posterior directed connectivity was maximally reduced (0.0282 ± 0.0772) during ketamine anesthesia compared to all other states (P < 0.05).
conclusionsKetamine anesthesia correlates most clearly with distinct changes in the theta bandwidth, including increased power and functional connectivity. Anterior-to-posterior connectivity in the alpha bandwidth becomes maximally depressed with anesthetic ketamine administration, suggesting a dose-dependent effect.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.