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.
Altered consciousness—from anesthesia and sleep to disorders of consciousness—involves distinct changes in thalamic nuclei. Analyzing fMRI data across these states, the authors found that propofol anesthesia disrupted pulvinar-cortical connections, sleep transitions affected specific nuclei (VLp, medial geniculate, centromedian), and disorders of consciousness showed widespread disconnections. Five key nuclei showed state-specific alterations, with higher-order nuclei (pulvinar, centromedian, mediodorsal) more consistently involved. Decreased local brain signal complexity occurred in 4–6 nuclei during anesthesia and 4–5 in patients with disorders of consciousness. The coupling between local fluctuation and connectivity varied systematically with consciousness state, suggesting potential therapeutic targets.