 Morphine consumption, the number of analgesia demands, and pain intensity at rest, during movement and with cough will be recorded at predetermined time intervals as follows: After surgery, when VAS pain score at rest falls below 30 mm, tDCS will be applied. VAS pain will be measured immediately before the intervention T0 and immediately after the intervention T1, and then regularly every one hour for the four hours Т2-Т5, and then every six hours Т6-Т9 for five days. 