The Effects of Sufentanil vs. Remifentanil in Total Intravenous Anesthesia With Remimazolam on Postoperative Pain

Inclusion Criteria: 1. 20years or older 2. Scheduled for laparoscopic-assisted gastrectomy 3. American Society of Anesthesiologists(ASA) physical status I and III Exclusion Criteria: 1. Emergency operation 2. Patients with a history of severe hypersensitivity reaction to dextran 40 3. Patients who cannot use patient controlled analgesia(PCA) 4. Patients with morbid obesity \[body mass index (BMI) \>35 kg/m2\] 5. Patients with history of uncontrolled hypertension (diastolic BP \>110mmHg) or DM 6. Patients with history of heart failure (unstable angina, congestive heart failure) 7. Patients with history of liver failure, renal failure, allergic to medicine 8. Patients with history of cerebrovascular disease (cerebral hemorrhage, cerebral ischemia) 9. Patients with history of uncontrolled psychiatric disease (PTSD, anxiety, depression) 10. Patients with obstructive sleep apnea 11. Patients who cannot read the consent form (examples: Illiterate, foreigner) 12. Patients who withdraw the consent