Inclusion Criteria:  patient scheduled for elective video-assisted thoracoscopic surgery American Society of Anesthesiologists physical grade I, II, III patient aged from 18 years old  Exclusion Criteria:  history of allergy in nonsteroidal anti-inflammatory drugs, or nefopam renal insufficiency liver insufficiency myocardial infarction glaucoma pregnant and lactating women at the time of surgery patient who did not consent to the use of patient-controlled analgesia