The Results of Sympathectomy

THis paper deals only with sympatlhectomy lor the cxtremities anld includles the results of three operations. For the lower limb, anl excision of the sympathetic chain, 3 to 6 cm. in length, centred opposite the third lumbar vertebra, has been the stanidard procedure. rhis includes the fourth lumbar ganglion and in many cases the third ganglion also. The extraperitoneal route is used, with spinal anaesthesia, and in bilateral conditions both sides are done at one session. For the upper limb, cervicothoracic gatnglionectomy was given up in Manichester in 1935, when Professor Telford introduced his preganglionic section. In this operation the sympathetic chain is sectionedl opposite the third rib, by the anterior approach, and after division of the rami from the second and third thoracic ganglia, the upper end is turned up and sutured to the scalenus anterior. No Horner's syndrome follows this procedure. The results can be considered under two headings, physiological and clinical. PHYSIOLOGICAI, lThere is an increased blood flow in the extremity from abolition of vasocon-strictor tone, and to this increase are due the beneficial results such as abolition of ischaemic pain, healing of ulcers, and rapid separation of dead tissue. The increase is greatest in the distal parts of the limbs because: 1. The greatest vasoconstrictor tone is in the skin which forms a greater proportion of the bulk of the digits than of any other part of the limbs. 2. The presence of arteriolo-venous anastomosis in the digits permits great increase in the blood flow. 3. Normal limbs have a skin temperature gradient, with the distal parts coldest because of greatest vasoconstrictor tone; after sympathectomy this gradient is abolished or even reversed. T he immediate result is a hot and dry extremity, with the skin temperature only slightly below blood heat, in the absence of severe organic arterial obstruction. The heat is not maintained, however, and the hand or foot begins to cool, often at the third day and with a pronounced fall in temperature on the fifth or sixth day. rhis fall is partly accounted for by the return of autonomous tone in the musculature of the arterioles, but to some extent it is due to the disappearance of the pyrexial reaction to the operation, caused, no doubt, by the absorption of products of tissue damage. Is this cooling an indication that sympathetic denervation is complete? To answer this question, tests for sympathetic activity must …