This prospective, randomized, double-blinded study is designed to evaluate the postoperative analgesic effect of the intravenous acetaminophen/ibuprofen fixed-dose combination in patients undergoing video-assisted thoracic surgery (VATS). We hypothesize that the intravenous acetaminophen/ibuprofen fixed-dose combination can significantly reduce postoperative opioid consumption and pain severity in patients with VATS.

Adult patients undergoing elective unilateral VATS wedge resection, segmentectomy, or lobectomy are randomly allocated to receive intravenous acetaminophen (1000 mg)/ibuprofen (300 mg) fixed-dose combination (n=48) or not (n=48). At the end of induction, the intervention group will receive intravenous acetaminophen (1000 mg)/ibuprofen (300 mg) for 15 min, every 6 hours, a total of 4 times. The control group will receive intravenous normal saline with the same volume and same time points as the intervention group receives.

Inclusion Criteria:

• Patients scheduled to undergo elective unilateral VATS segmentectomy or lobectomy under general anesthesia
• American Society of Anesthesiologists (ASA)physical classification I-II
• Consent to IV-patient controlled analgesia use
• Willingness and ability to sign an informed consent document

Exclusion Criteria:

• Do not understand our study
• Allergies to anesthetic or analgesic medications
• Continuous local anesthetics infiltration for postoperative pain control
• Patients who receive mechanical ventilation more than 2 hours after surgery
• Pregnancy/Breastfeeder
• Medical or psychological disease that can affect thetreatment response

The nurse who is not involved in this study knows the allocated group and sends the bottle of the drug which looks the same in both groups, to the operation room and ward.

The care provider, investigator, patients, and outcomes assessor will be not informed of the infusion of the drug by not attaching an identifiable label so that it cannot be distinguished from normal saline.