sympathectomy /sim′pəthek″təmē/ [Gk, sympathein, to feel with, ektomē, excision] , a surgical interruption of part of the sympathetic nerve pathways to relieve chronic pain or to promote vasodilation in vascular diseases, such as arteriosclerosis, claudication, Buerger’s disease, and Raynaud’s phenomenon. The sheath around an artery carries the sympathetic nerve fibers that control constriction of the vessel. Removal of the sheath causes the vessel to relax and expand and allows more blood to pass through it. The operation also may be done with a vascular graft to increase the blood flow through the graft area. Preoperatively the physician may assess the effect of surgery by injecting sympathetic ganglia with a local anesthesia to interrupt temporarily the sympathetic nerve impulses. The nerves lie along the spinal column and are approached through the back or the neck, by using local anesthesia. Postoperatively, the adequacy of circulation and peripheral nervous supply in the affected extremity is monitored. An arteriogram shows a widened pathway.
