Hyman S A, Parris W C, Prysi N H, Skelley C, Lindsey K
Department of Anesthesiology, Vanderbilt University Medical Center, Nashville, Tennessee 37232-2125.
Clin J Pain. 1991 Sep;7(3):226-9. doi: 10.1097/00002508-199109000-00009.
Median nerve somatosensory evoked potentials (SEPs) were monitored in patients with chronic pain before and after stellate ganglion blockade. A change caused by the syndrome or by the block would suggest that SEPs might be useful in the diagnosis and treatment of chronic pain. We observed 20 subjects. Group I (n = 10) had chronic pain not involving the upper extremity. Group II (n = 8) had reflex sympathetic dystrophy of the arm. All patients underwent unilateral stellate ganglion block using an anterior paratracheal approach. The SEPs were recorded by median nerve stimulation on the blocked (affected) side and unblocked (unaffected) side before and 30 min after the block. Recording sites were ipsilateral brachial plexus, the cervical spinal cord, and the contralateral sensory cortex. There were no between-group differences before or after the block. Paired analysis within each group showed that the SEPs were not different from baseline (unaffected side before block) at any time throughout the study. We conclude that since SEPs are not changed by the reflex sympathetic dystrophy or stellate ganglion block, they would not be useful in the evaluation of pain or in determining the effectiveness of sympathetic block. Both the pain and the block appear to involve alteration of conducting pathways separate from those monitored by median nerve SEPs.
在星状神经节阻滞前后，对慢性疼痛患者进行正中神经体感诱发电位（SEP）监测。由该综合征或阻滞引起的变化将提示SEP可能对慢性疼痛的诊断和治疗有用。我们观察了20名受试者。第一组（n = 10）患有不涉及上肢的慢性疼痛。第二组（n = 8）患有手臂反射性交感神经营养不良。所有患者均采用气管旁前路进行单侧星状神经节阻滞。在阻滞前和阻滞后30分钟，通过刺激正中神经在阻滞（患）侧和未阻滞（未患）侧记录SEP。记录部位为同侧臂丛神经、颈脊髓和对侧感觉皮层。阻滞前后两组之间无差异。每组内的配对分析表明，在整个研究过程中的任何时间，SEP与基线（阻滞前未患侧）均无差异。我们得出结论，由于SEP不会因反射性交感神经营养不良或星状神经节阻滞而改变，因此它们在评估疼痛或确定交感神经阻滞的有效性方面没有用处。疼痛和阻滞似乎都涉及与正中神经SEP所监测的传导通路不同的传导通路改变。
