In patients with disorders of consciousness, the anesthetic esketamine preserved brain electrical complexity and gamma-band functional connectivity better than propofol during spinal cord stimulator implantation. Esketamine was linked to faster recovery of spontaneous breathing (12 vs. 17 minutes on average) and a lower need for blood pressure support during surgery. At three months, esketamine was associated with significantly improved consciousness outcomes. The findings suggest esketamine may offer neuroprotective benefits in this population.
Global signal regression (GSR), a common preprocessing step in fMRI analysis, affects brain activity patterns differently depending on the anesthetic agent used. Using fMRI data from patients under general anesthesia, the work shows that GSR alters specific network connections under propofol but broadly reduces connectivity differences under sevoflurane. Network topology analyses reveal that GSR minimally affects propofol-induced changes in graph theoretical measures but significantly diminishes sevoflurane-related network alterations. These findings indicate that GSR's impact on functional brain organization is anesthetic-specific, with sevoflurane-induced changes being particularly sensitive to global signal removal. The results suggest that GSR should be applied cautiously when comparing different anesthetic agents.