Study on EEG neural oscillation characteristics during ciprofol general anesthesia

Ciprofol, a novel intravenous anesthetic with GABAA affinity akin to propofol, lacks characterized electroencephalogram (EEG) oscillation profiles during anesthesia.

This prospective observational study included 54 patients undergoing surgery, divided into two groups: 30 adults (18-64 years) and 24 elderly (≥ 65 years). The EEG monitor recorded frontal region EEG, and we analyzed spectral power, wavelet coherence, and phase-amplitude coupling (PAC) across various states.

In the awake state, the spectral analysis power, wavelet coherence, and PAC were similar between the patient groups. Under anesthesia, both groups exhibited dominant slow oscillation (SO) and alpha oscillations, but the elderly group showed significantly lower alpha power (adult 4.367 [1.492-6.059] vs. elderly 1.729 [- 2.340-4.096], P < 0.001) and wavelet coherence (adult 0.0375 [0.0092-0.0935] vs. elderly 0.0073 [0.0030-0.0235], P = 0.041) compared to the adult group. During the recovery period, the restoration of beta/gamma activity and the increase in the intensity of the SO-alpha modulation index (MI) indicated a gradual recovery of consciousness. Frontal alpha power showed age dependency under ciprofol-maintained general anesthesia. Alpha-band wavelet coherence and the SO-alpha MI exhibited no significant age dependence, and the PAC pattern weakened with age.

This study characterizes the EEG neural oscillation dynamics during ciprofol-induced general anesthesia. Despite the physiological decline in spectral power associated with increasing age, wavelet coherence and PAC demonstrate remarkable stability across different age cohorts. These findings support their potential as reliable, age-independent biomarkers for monitoring the depth of anesthesia.