Clinical neurophysiology : official journal of the International Federation of Clinical Neurophysiology
March 1, 2025
Weizhuang Kong, Zhe Sun, Jing Zhu et al.
Nitrous oxide inhalation produced time-dependent increases in brain entropy, particularly in the frontal lobe, among patients with treatment-resistant depression. These entropy changes, measured via multivariate multiscale entropy analysis of resting-state EEG, correlated with symptom severity and treatment efficacy, suggesting frontal region temporal-spatial brain entropy may serve as a biomarker for treatment-resistant depression and its treatment outcomes.
Psychiatry research
August 1, 2023
Jin Liu, Xiaotian Zhao, Xiyu Wei et al.
A double-blinded, placebo-controlled randomized trial tested whether nitrous oxide (N2O) improves cognitive function in 44 patients with treatment-resistant depression. Thirty-four patients completed cognitive tests before treatment and at 1 and 2 weeks after a one-hour inhalation of 50% N2O/50% oxygen or placebo (50% air/50% oxygen). Although N2O did not produce a significant antidepressant effect at 1 week, patients who received N2O showed better executive function at 1 week compared with placebo, and this improvement remained after controlling for changes in depressive symptoms. No significant differences were found in subjective cognitive function, processing speed, or attention over the 2-week follow-up. The results suggest N2O may have a pro-cognitive effect on executive function independent of mood improvement.
Psychiatry Research
January 1, 2023
Xuexiao Shao, Danfeng Yan, Wenwen Kong et al.
In patients with treatment-resistant depression, a single 1-hour inhalation of nitrous oxide improved depressive symptoms more than a placebo, as measured by the 17-Hamilton Depression Rating Scale. The treatment altered brain function, shown by changes in event-related potential components (N1, P1, N2, P2) and increased functional connectivity networks. These brain changes correlated with symptom reduction, suggesting nitrous oxide works by modifying brain function.
Psychiatry research
November 1, 2022
Danfeng Yan, Bangshan Liu, Xiyu Wei et al.
A single one-hour inhalation of 50% nitrous oxide (N2O) mixed with oxygen rapidly alleviated depression in patients with treatment-resistant depression in China, but the effect lasted no more than one week. In a double-blind, placebo-controlled trial, 44 patients were randomized to receive either 50% N2O or a placebo mixture. Depression scores on the Hamilton Depression Rating Scale were significantly lower in the N2O group at two hours and 24 hours after treatment, but no significant difference remained at one week or two weeks. Patients receiving N2O reported more adverse events, all of which resolved within 24 hours, and no serious adverse events occurred.