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.

Morbidly obese patients undergoing laparoscopic sleeve gastrectomy experience a relatively high incidence of postoperative nausea and vomiting, but no effective treatment method has been established yet to prevent them. Through this study, the investigators can expect that if a dual-chamber patient-controlled analgesia device can provide effective analgesia while reducing the amount of opioid used, and thus reduce postoperative nausea and vomiting, it can have the effect of increasing the quality of recovery and satisfaction of participants who have undergone laparoscopic sleeve gastrectomy. Furthermore, this dual-chamber patient-controlled analgesia device can be applied to various surgeries and various patient groups who are at risk for postoperative nausea and vomiting, and it is expected that it can be adapted as one of the methods to prevent postoperative nausea and vomiting.

Inclusion Criteria:

• Adult females aged 19 to 65 years
• American Society of Anesthesiologists physical status (ASA class) 1 to 3
• Patients scheduled for laparoscopic sleeve gastrectomy under general anesthesia
• Patients requesting the use of IV-PCA after surgery

Exclusion Criteria:

• Patients with hypersensitivity to the drugs used in this study (Ketorolac, Fentanyl)
• Patients with alcohol or drug dependence, long-term use of opioids or analgesics
• Patients with liver disease or renal failure
• Patients with peptic ulcer, patients with gastrointestinal bleeding predisposition
• Patients with suspected cerebrovascular hemorrhage, organic disorders of the head related to increased intracranial pressure
• Patients with bronchial asthma or bronchospasm symptoms
• Patients with severe respiratory depression
• Nasal polyps, angioedema
• Patients with or history of convulsive disease
• Patients for whom the use of neuromuscular blocking agents is contraindicated