Postoperative nausea and vomiting (PONV) are the most common complications that can occur after general anesthesia. Postoperative use of opioids and morbid obesity have been reported as risk factors of PONV. In this study, the investigators aimed to compare the degree of postoperative side effects and pain control when an intravenous patient-controlled analgesia combining fentanyl and ketorolac via a dual-chamber device was provided to participants undergoing laparoscopic sleeve gastrectomy.