Objective This study aims to explore the effect of propofol deep sedation on brain activity by observing changes in amplitude of low-frequency fluctuations(ALFF)during this state.Methods This was a prospective,observational study involving healthy volunteers aged 18 to 60 years.Subjects underwent target-controlled infusion of propofol while fully awake,and their sedation status was assessed using the modified Observer's Assessment of Alertness/Sedation Scale.Resting-state functional magnetic resonance imaging(rs-fMRI)scans were performed in both awake and deep sedation states to analyze changes in mean ALFF(mALFF).Re-sults A total of 26 healthy volunteers were included in the study.The average effect site concentration for achieving deep sedation with propofol was(2.35±0.49)mg/L.Compared with the awake state,mALFF increased in the bilateral temporal lobes,parts of the fron-tal lobes,and occipital regions during deep sedation(all P＜0.05),while mALFF decreased in the bilateral frontal lobes,the middle fron-tal gyrus,and parts of the occipital regions(all P＜0.05).The difference in the number of voxels between regions with increased mALFF and those with decreased mALFF was not statistically significant(P＞0.05).Conclusions During deep sedation with propofol,neuro-nal activity is enhanced in the bilateral temporal lobes,parts of the frontal lobes,and occipital regions,while it is reduced in the bilater-al frontal lobes,the middle frontal gyrus,and parts of the occipital regions.These findings suggest that the sedative mechanism of propo-fol may involve combined effect of enhancement in some brain regions and suppression in others.
关键词
丙泊酚/静息态功能磁共振成像/低频振幅
Key words
Propofol/Resting-state functional magnetic resonance imaging/Amplitude of low-frequency fluctuations
万方数据