A small insignificant pneumothorax can be expected after ETS in about    75% of cases [15], which gets spontaneously absorbed, usually within   24  h. 
Comparing T2 and T2–T3 ablation in thoracoscopic sympathectomy for palmar hyperhidrosis: a randomized control trial
A. N. Katara, J. P. Domino, W.-K. Cheah, J. B. So, C. Ning, D. Lomanto
Received: 13 October 2006/Accepted: 2 November 2006
Surg Endosc (2007) DOI: 10.1007/s00464-007-9241-9
[15] Ojimba TA, Cameron AEP (2004) Drawbacks of endoscopic thoracic sympathectomy. Br J Surg 91: 264–269 
Permanent side effects included  compensatory sweating in 67.4%,  gustatory sweating in 50.7% and  Horner's trias in 2.5%. However, patient  satisfaction declined over  time, although only 1.5% recurred. This left  only 66.7% satisfied, and a  26.7% partially satisfied. Compensatory and  gustatory sweating were  the most frequently stated reasons for  dissatisfaction. Individuals  operated for axillary hyperhidrosis without  palmar involvement were  significantly less satisfied (33.3% and 46.2%,  respectively).
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1234291/
"Sympathectomy is a technique about which we have limited knowledge, applied to disorders about which we have little understanding." Associate Professor Robert Boas, Faculty of Pain Medicine of the Australasian College of Anaesthetists and the Royal College of Anaesthetists, The Journal of Pain, Vol 1, No 4 (Winter), 2000: pp 258-260
The amount of compensatory sweating depends on the patient, the damage that the white rami communicans incurs, and the amount of cell body reorganization in the spinal cord after surgery.
Other potential complications include inadequate resection of the ganglia, gustatory sweating, pneumothorax, cardiac dysfunction, post-operative pain, and finally Horner’s syndrome secondary to resection of the stellate ganglion.
www.ubcmj.com/pdf/ubcmj_2_1_2010_24-29.pdf
After severing the cervical sympathetic trunk, the cells of the cervical sympathetic ganglion undergo transneuronic degeneration
After severing the sympathetic trunk, the cells of its origin undergo complete disintegration within a year.
http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0442.1967.tb00255.x/abstract
Other potential complications include inadequate resection of the ganglia, gustatory sweating, pneumothorax, cardiac dysfunction, post-operative pain, and finally Horner’s syndrome secondary to resection of the stellate ganglion.
www.ubcmj.com/pdf/ubcmj_2_1_2010_24-29.pdf
After severing the cervical sympathetic trunk, the cells of the cervical sympathetic ganglion undergo transneuronic degeneration
After severing the sympathetic trunk, the cells of its origin undergo complete disintegration within a year.
http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0442.1967.tb00255.x/abstract
 
