In recent years a much more hopeful attitude has come into the literature concerning vascular diseases in the extremities.1One of the important factors in this has been the recognition of vasospasm as a significant, often the decisive, element in many local circulatory disturbances. In the conservative therapy of those vascular diseases that lead to gangrene the central problem is terminal nutrition, the blood supply to the distal part of the extremity. Consequently, today in studying such conditions it becomes of paramount importance to determine not only the presence or absence of vascular spasm and occlusion but also the relative contributions of each to the circulatory deficiency in the extremity. The latter is now possible. Paralysis of the sympathetic innervation of the part temporarily overcomes vasospasm.2In individuals with normal blood vessels such regional paralysis or a general anesthesia abolishes the vasoconstrictor gradient and all areas of the