Bilateral ETSs were performed in a one-stage procedure by the same surgeon. General anaesthesia using single-lung ventilation technique was performed and patient was placed in standard lateral thoracotomy position. Immediately after the induction of anaesthesia, a local infiltration with 2% lidocaine and epinephrine was injected at each port 5 minutes before the incision to reduce postoperative pain. The first port was placed in the 3th intercostal space below and anterior to inferior angle of scapula and through that a 10 mm 30 degree camera was inserted. A second 5 mm working port was placed at the same intercostal space in the anterior axillary line. After identification of sympathetic chain, in Sympathectomy Group the T3 ganglion was excised at the top of the third rib while in Sympathicotomy Group the sympathetic chain was resected between T2-T3 ganglia at the same level but the T3 ganglion was left intact. At the end of the procedure, a 16 F drainage was inserted through the port and the lung was re-inflated to allow the air drainage from pleural cavity and to prevent pneumothorax. The drain was subsequently removed.