Sevoflurane will be used for anesthesia induction and maintance. Laryngeal mask airway will be placed without neuromuscular blocking agent. In group P (popliteal block), a single dose of 0.3ml.kg(-1) of 0.25% bupivacaine will be performed for popiteal nerve block (with ultrasound guidence). In group C ( control), only plaster cover will be applied without nerve block for sham procedure to provide double-blinded study. Intraoperative heart rate, mean arterial pressure, BIS (bispectral index) values, sevoflurane consumption will be recorded ten minutes interval. Wong Baker faces scale and skin conductance fluctuations will be recorded at postoperative 0, 10th min, 20th min , 1st h, 4th h, 12th h qnd 24th h. Total analgesic consumption (paracetamol orally ) will be recorded.