Clinical and physiologic evaluation of stellate ganglion blockade for complex regional pain syndrome type I. (Ludwig‐Maximilians‐University, Munich, Germany) Clin J Pain.2001;17:94–100.

Stellate ganglion blockade with local anesthetics was carried out via an anterior paratracheal approach in 33 patients suffering from complex regional pain syndrome type I. Twenty‐three (70%) of the 33 patients developed an increased in temperature difference between the treated hand and the contralateral hand of more than 1.5°C after the procedure, which is a clinical sign of sympathicolysis. In 48% of these patients, the sympathetic function test showed an undisturbed sympathetic nervous function. In 10 patients, no significant increase in temperature difference was observed. Only 7 patients with pain relief revealed both clinical sympathicolysis and extinguished sympathetic nerve function and qualified for sympathetically maintained pain. Conclude that clinical investigation is not reliable in the assessment of stellate ganglion blockade. Proof of sympathetically maintained pain based on pain relief after stellate ganglion blockade is not conclusive.