Postoperative pain remains a major challenge after video-assisted thoracoscopic surgery (VATS), despite the use of multimodal analgesia. This randomized, triple-blind, placebo-controlled clinical trial will evaluate whether adding a 5 mcg/hour transdermal buprenorphine patch to the standard multimodal analgesic regimen reduces postoperative pain in adults undergoing unilateral VATS. Participants will be randomly assigned to receive either transdermal buprenorphine or placebo in addition to standard analgesia. Postoperative pain will be assessed at 24, 48, and 72 hours and 7 days after surgery. Secondary outcomes include opioid rescue requirements, length of hospital stay, postoperative nausea and vomiting, pruritus, and urinary retention.