Blood flow in the anterior tibial skeletal muscle group and skin temperature of the foot were measured before and after epidural sympathetic nerve blockade in 8 patients with no evidence of arterial insufficiency, and in 17 patients with obliterative arterial disease of the lower limb. Muscle blood flow was calculated from the clearance of locally injected xenon Xe 133 in order to measure tissue nutritional blood flow only.
Resting muscle blood flow was significantly reduced, and skin temperature of the foot significantly increased after sympathetic block in both groups of patients.
It is suggested that the intense skin vasodilation due to the release of vasoconstrictor tone causes redistribution of total limb blood flow with a reduction of the blood flow to muscle which has low metabolic requirements at rest.
Wright CJ, Cousins MJ. Blood Flow Distribution in the Human Leg Following Epidural Sympathetic Blockade. Arch Surg. 1972;105(2):334-337. doi:10.1001/archsurg.1972.04180080180030