Propofol-Induced Moderate–Deep Sedation Modulates Pediatric Neural Activity: A Functional Connectivity Study

Abstract

Background

Previous studies have demonstrated the underlying neurophysiologic mechanism during general anesthesia in adults. However, the mechanism of propofol-induced moderate–deep sedation (PMDS) in modulating pediatric neural activity remains unknown, which therefore was investigated in the present study based on functional magnetic resonance imaging (fMRI).

Methods

A total of 41 children (5.10 ± 1.14 years, male/female 21/20) with fMRI were employed to construct the functional connectivity network (FCN). The network communication, graph-theoretic properties, and network hub identification were statistically analyzed (t test and Bonferroni correction) between sedation (21 children) and awake (20 children) groups. All involved analyses were established on the whole-brain FCN and seven sub-networks, which included the default mode network (DMN), dorsal attentional network (DAN), salience network (SAN), auditory network (AUD), visual network (VIS), subcortical network (SUB), and other networks (Other).

Results

Under PMDS, significant decreases in network communication were observed between SUB-VIS, SUB-DAN, and VIS-DAN, and between brain regions from the temporal lobe, limbic system, and subcortical tissues. However, no significant decrease in thalamus-related communication was observed. Most graph-theoretic properties were significantly decreased in the sedation group, and all graphical features of the DMN showed significant group differences. The superior parietal cortex with different neurological functions was identified as a network hub that was not greatly affected.

Conclusions

Although the children had a depressed level of neural activity under PMDS, the crucial thalamus-related communication was maintained, and the network hub superior parietal cortex stayed active, which highlighted clinical practices that the human body under PMDS is still perceptible to external stimuli and can be awakened by sound or touch.