In search of Universal Cortical Power Changes Linked to NMDA-Antagonist based Anesthetic Induced Reductions in Consciousness
Andria Pelentritou, Levin Kuhlmann, John Cormack, Steven McGuigan, Will Woods, Suresh Muthukumaraswamy, David T. J. Liley
bioRxiv (Cold Spring Harbor Laboratory) March 9, 2019 preprint DOI: 10.1101/572636 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Crossover study |
|---|---|
| Sample size | 22 |
| Population | Healthy males |
| Interventions | Xenon Nitrous oxide |
| Dose | 0.25, 0.50, 0.75 equi MAC-awake for both gases; 1.30 MAC-awake xenon |
| Topics | Ketamine |
| Keywords | Anesthetic Nmda receptor Magnetoencephalography Anesthesia Electroencephalography Crossover study Placebo |
| Citations | 1 |
| Key points | Xenon and nitrous oxide produce distinct, frequency-dependent changes in cortical oscillatory source power, with Xe increasing low-frequency power and N2O reducing frontal alpha and increasing gamma power. |
Abstract
B. Abstract Background. Despite their intriguing nature, investigations of the neurophysiology of N-methyl-D-aspartate (NMDA)-antagonists Xenon (Xe) and nitrous oxide (N 2 O) are limited and have revealed inconsistent frequency-dependent alterations, in spectral power and functional connectivity. Discrepancies are likely due to using low resolution electroencephalography restricted to sensor level changes, concomitant anesthetic agent administration and dosage. Our intention was to describe the effects of equivalent stepwise levels of Xe and N 2 O administration on oscillatory source power using a crossover design, to explore universal mechanisms of NMDA-based anesthesia. Methods. 22 healthy males participated in a study of simultaneous magnetoencephalography and electroencephalography recordings. In separate sessions, equivalent subanesthetic doses of gaseous anesthetic agents N 2 O and Xe (0.25, 0.50, 0.75 equi MAC-awake) and 1.30 MAC-awake Xe (for Loss of Responsiveness) were administered. Source power in various frequency bands was computed and statistically assessed relative to a conscious baseline. Results. Delta (l-4Hz) and theta (4-8Hz) band power was significantly increased at the highest Xe concentration (42%, 1.30 MAC-awake) relative to baseline for both magnetoencephalography and electroencephalography source power (p<0.005). A reduction in frontal alpha (8-13 Hz) power was observed upon N 2 O administration, and shown to be stronger than equivalent Xe dosage reductions (p=0.005). Higher frequency activity increases were observed in magnetoencephalographic but not encephalographic signals for N 2 O alone with occipital low gamma (30-49Hz) and widespread high gamma (51-99Hz) rise in source power. Conclusions. Magnetoencephalography source imaging revealed unequivocal and widespread power changes in dissociative anesthesia, which were divergent to source electroencephalography. Loss of Responsiveness anesthesia at 42% Xe (1.30 MAC-awake) demonstrated, similar to inductive agents, low frequency power increases in frontal delta and global theta. N 2 O sedation yielded a rise in high frequency power in the gamma range which was primarily occipital for lower gamma bandwidth (3049 Hz) and substantially decreased alpha power, particularly in frontal regions. Clinical trial number and Registry URL Not applicable. Prior Presentations Pelentritou Andria, Kuhlmann Levin; Lee Heonsoo; Cormack John; Mcguigan Steven; Woods Will; Sleigh Jamie; Lee UnCheol; Muthukumaraswamy Suresh; Liley David. Searching For Universal Cortical Power Changes Linked To Anesthetic Induced Reductions In Consciousness. The Science of Consciousness April 4 th 2018. Tucson, Arizona, USA. Summary Statement Not applicable.
Comparable studies
Other randomized controlled trials on ketamine, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Subanesthetic Effects of the Noncompetitive NMDA Antagonist, Ketamine, in Humans Healthy human subjects recruited from the community | 1994 | Randomized controlled trial | n = 19 |
| Antidepressant Efficacy of Ketamine in Treatment-Resistant Major Depression: A Two-Site Randomized Controlled Trial Patients with treatment-resistant major depression experiencing a major depressive episode | 2013 | Randomized controlled trial | n = 73 |
| Remifentanil-induced Postoperative Hyperalgesia and Its Prevention with Small-dose Ketamine Patients undergoing major abdominal surgery | 2005 | Randomized controlled trial | n = 75 |
| Efficacy of Intravenous Ketamine for Treatment of Chronic Posttraumatic Stress Disorder Patients with chronic PTSD related to a range of trauma exposures | 2014 | Randomized controlled trial | n = 41 |
| Ketamine-Induced Deficits in Auditory and Visual Context-Dependent Processing in Healthy Volunteers Healthy volunteers | 2000 | Single-blind placebo-controlled study | n = 20 |
Citations in the library
Cites 9
- Psychometric Evaluation of the Altered States of Consciousness Rating Scale (OAV) PLoS One August 31, 2010
- Unresponsiveness ≠ Unconsciousness Anesthesiology February 7, 2012
- Disruption of Frontal–Parietal Communication by Ketamine, Propofol, and Sevoflurane Anesthesiology May 22, 2013
- Evidence that Subanesthetic Doses of Ketamine Cause Sustained Disruptions of NMDA and AMPA-Mediated Frontoparietal Connectivity in Humans Journal of Neuroscience August 19, 2015
- Recording Brain Electromagnetic Activity During the Administration of the Gaseous Anesthetic Agents Xenon and Nitrous Oxide in Healthy Volunteers. Journal of Visualized Experiments January 13, 2018
and 4 more in the library