Niesters Marieke, Sitsen Elske, Oudejans Linda, Vuyk Jaap, Aarts Leon P H J, Rombouts Serge A R B, de Rover Mischa, Khalili-Mahani Najmeh, Dahan Albert
1 Department of Anesthesiology, Leiden University Medical Center , Leiden, The Netherlands .
Brain Connect. 2014 Aug;4(6):404-16. doi: 10.1089/brain.2014.0247.
Patients may perceive paradoxical heat sensation during spinal anesthesia. This could be due to deafferentation-related functional changes at cortical, subcortical, or spinal levels. In the current study, the effect of spinal deafferentation on sensory (pain) sensitivity was studied and linked to whole-brain functional connectivity as assessed by resting-state functional magnetic resonance imaging (RS-fMRI) imaging. Deafferentation was induced by sham or spinal anesthesia (15 mg bupivacaine injected at L3-4) in 12 male volunteers. RS-fMRI brain connectivity was determined in relation to eight predefined and seven thalamic resting-state networks (RSNs) and measured before, and 1 and 2 h after spinal/sham injection. To measure the effect of deafferentation on pain sensitivity, responses to heat pain were measured at 15-min intervals on nondeafferented skin and correlated to RS-fMRI connectivity data. Spinal anesthesia altered functional brain connectivity within brain regions involved in the sensory discriminative (i.e., pain intensity related) and affective dimensions of pain perception in relation to somatosensory and thalamic RSNs. A significant enhancement of pain sensitivity on nondeafferented skin was observed after spinal anesthesia compared to sham (area-under-the-curve [mean (SEM)]: 190.4 [33.8] versus 13.7 [7.2]; p<0.001), which significantly correlated to functional connectivity changes observed within the thalamus in relation to the thalamo-prefrontal network, and in the anterior cingulate cortex and insula in relation to the thalamo-parietal network. Enhanced pain sensitivity from spinal deafferentation correlated with functional connectivity changes within brain regions involved in affective and sensory pain processing and areas involved in descending control of pain.
患者在脊髓麻醉期间可能会感觉到反常热感。这可能是由于皮质、皮质下或脊髓水平与传入神经阻滞相关的功能变化所致。在本研究中，研究了脊髓传入神经阻滞对感觉（疼痛）敏感性的影响，并将其与通过静息态功能磁共振成像（RS-fMRI）评估的全脑功能连接性相关联。在12名男性志愿者中，通过假手术或脊髓麻醉（在L3-4注射15mg布比卡因）诱导传入神经阻滞。RS-fMRI脑连接性是相对于八个预定义的和七个丘脑静息态网络（RSN）确定的，并在脊髓/假注射前、注射后1小时和2小时进行测量。为了测量传入神经阻滞对疼痛敏感性的影响，每隔15分钟测量一次非传入神经阻滞皮肤对热痛的反应，并将其与RS-fMRI连接性数据相关联。脊髓麻醉改变了与体感和丘脑RSN相关的、参与疼痛感知的感觉辨别（即与疼痛强度相关）和情感维度的脑区之间的功能脑连接。与假手术相比，脊髓麻醉后观察到非传入神经阻滞皮肤的疼痛敏感性显著增强（曲线下面积[平均值（标准误）]：190.4[33.8]对13.7[7.2]；p<0.001），这与丘脑内与丘脑-前额叶网络相关的功能连接变化以及前扣带回皮质和岛叶内与丘脑-顶叶网络相关的功能连接变化显著相关。脊髓传入神经阻滞引起的疼痛敏感性增强与参与情感和感觉性疼痛处理的脑区以及参与疼痛下行控制的区域内的功能连接变化相关。
