全麻状态下静脉麻醉药丙泊酚对大脑功能连结性的影响

Effects of intravenous anesthetic propofol on brain functional connectivity under surgical anesthesia level

目的应用静息态功能磁共振(rest state functional magnetic resonance imaging,rs-fMRI)成像技术观察深度麻醉下静脉麻醉药丙泊酚对大脑功能连结性的影响。方法 6位在术中磁共振手术室行经蝶垂体瘤切除术的神经外科患者,采用丙泊酚靶控输注(效应室浓度4μg/mL)进行麻醉诱导并维持。分别在患者处于清醒、麻醉和麻醉下进行疼痛刺激三种状态时应用3.0T场强磁共振仪进行扫描。获取的影象学资料应用AFNI软件分析大脑默认网络,体感运动网络和疼痛相关网络的功能连结性,并用SPSS统计软件进行统计分析。结果种子体素相关分析法结果显示,与清醒状态相比,丙泊酚导致在外科麻醉水平大脑默认网络、躯体运动感觉皮层以及疼痛相关脑区岛叶皮层的脑功能连接显著下降,表现为扣带回、内侧前额叶、岛叶等脑区被抑制(P<0.01)。疼痛刺激后在躯体运动感觉皮层及疼痛相关脑区的功能连接呈现部分恢复,表现为右侧舌回、梭状回、岛叶及扣带回区出现不同程度的激活(P<0.01);而默认网络的功能连接则进一步下降(P<0.01)。结论在外科麻醉水平,丙泊酚导致大脑各脑区功能连接减弱,提示可能与意识水平降低相关。扣带回、岛叶以及内侧前额叶可能是丙泊酚中枢作用靶点。而疼痛刺激虽可恢复部分脑区功能连结性,但重要脑区的功能连结性仍显著下降。

Objective To investigate the effects of intravenous anesthetic propofol under surgical anesthesia level on brain functional connectivity using rest state functional magnetic resonance imaging （rs-fMRI） technique.Methods Six neurosurgical patients undergoing pituitary tumor resection were enrolled in this study.They were induced to unconscious and maintained general anesthesia with propofol target controlled infusion （effect-site concentration 4 μg/mL）.Three fMRI scans with 3.0 T high field MRI scanner were performed under wake,general anesthesia and pain stimulation,respectively.With AFNI software,the obtained neuroimage data were used for analyzing function connectivity of default mode network,sensormotor network and painrelated network.And SPSS software was used for statistic analysis.Results The seed voxel correlation analysis method showed that compared with awake status,propofol significantly suppressed functional connectivity of default mode network,sensorimotor network and pain-related network which are important relevant to consciousness and nociceptive stimulation under deep anesthesia level.The involved brain regions included cingulate,medial prefrontal and insular cortex （P〈0.01）.When pain stimulation applied,right lingual gyrus,fusiform gyrus,insular cortex and cingulate were activated （P〈0.01）,indicating the brain functional connectivity in somatic sensormotor cortex,and the network consisted of pain-related brain regions were partially restored.However,functional connectivity of default network further declined （P〈0.01）.Conclusions Propofol significantly suppressed functional connectivity of several neural networks,suggesting role of functional connectivity disruption between brain regions in propofol-induced loss of consciousness.The cingulate,medial prefrontal and insular cortex may be the effect sites of propofol in the central nervous system.The functional connectivity of important neural networks was still suppressed,although pain stimulation under surgical anesthesia level could partially restore connectivity of several brain regions.