Cold hypersensitivity after sympathectomy for Raynaud's disease.

Two patients with socially handicapping Raynaud's disease underwent bilateral upper thoracic sympathectomy. One to two days after the operation, both developed local hypersensitivity to cold in the form of a rebound. The cold hypersensitivity persisted in one of the patients, although complete degeneration of vasoconstrictor fibres was proven by absence of the sympathetic veno-arteriolar reflex after sympathectomy. Pre-operative sympathetic blockade could not predict the outcome of sympathectomy.