Changes in information integration and brain networks during propofol-, dexmedetomidine-, and ketamine-induced unresponsiveness.
British journal of anaesthesia March 1, 2024 Zhenhu Liang, Yu Chang, Xiaoge Liu et al. 10 citations
Information integration and brain network measures derived from EEG can distinguish conscious from unconscious states induced by three different anaesthetics. In 72 participants given propofol, dexmedetomidine, or ketamine until they lost responsiveness, permutation cross mutual information (PCMI) within frontal, parietal, and occipital regions decreased during unresponsiveness—for example, frontal within-area PCMI fell from 0.54 to 0.46. Alpha-band PCMI in the frontal region and gamma-band PCMI in posterior areas also dropped. Network analyses showed reduced clustering coefficients and nodal efficiency in frontal, parietal, and occipital areas, while normalized path length increased in delta, theta, and gamma bands, indicating impaired global integration. The three drugs produced similar changes, suggesting a common EEG signature of anaesthesia-induced unconsciousness.