The excision of neural structures which elaborate adrenergic substances during the process of regulating visceral function continues to be a valuable investigative and therapeutic maneuver.
In general, sympathtectomy has been used for one or more of the following purposes:
1/ to eliminate tonic or engendered responses which depend upon impulses in adrenergic nerves;
2/ to eliminate visceral stores of adrenergic substances which depend upon the integrity of the postganglionic sympathetic innervation;
3/ to eliminate postganglionic sympathetic tissue as a locus for the synthesis, uptake, binding, release and metabolism of adrenergic substances;
4/ to eliminate visceral afferent fibers which are frequently distributed in common with autonomic nerves.
It is clear that sympathectomy is not a selective excision of adrenergic elements only. It is well recognized that preganglionic sympathectomy involves division of cholinergic elements and sensory fibers.
Although the larger portion of sympathetic inflow to an organ can be eliminated by excision of relatively large, well defined anatomical structures in the sympathetic nervous system, there may be many aberrant pathways of innervation. The structure of the terminal apparatus for innervation in most organs is not clear, and it is not known how widely or how rapidly a seemingly small residue of postganglionic fibers can proliferate or branch to occupy sites of degenerated elements.
Theodore Cooper
Surgical Sympathectomy and Adrenergic Function
Department of Surgery, St Louis University School of Medicine
Pharmacological Reviews, Vol. 18, No.1
http://pharmrev.aspetjournals.org/cgi/pdf_extract/18/1/611