Acute Effects of Esketamine on the EEG Power Spectrum and Signal Complexity in Prolonged Disorders of Consciousness: A Prospective Exploratory Cohort Study.
Journal of neurosurgical anesthesiology June 15, 2026 Yi Liang, Wanning Yang, Xinxin Wang et al.
In patients with prolonged disorders of consciousness, a one-hour intravenous infusion of esketamine (0.3 mg/kg/h) altered brain activity as measured by electroencephalography. The drug suppressed delta wave power while increasing beta and gamma wave power across the whole brain, and increased alpha wave power specifically in patients diagnosed as vegetative state/unresponsive wakefulness syndrome. Signal complexity, measured by Lempel-Ziv complexity, increased in the parietal and occipital brain regions. In minimally conscious patients, this complexity increase persisted for 30 minutes after the infusion stopped, while changes were transient in vegetative state patients. However, these neurophysiological changes were not accompanied by any improvements in behavioral responsiveness as assessed by the Coma Recovery Scale-Revised.