Stress reactions caused by surgical stimuli can cause sympathetic nervous system activation and increased stress hormones, such as catecholamines, inflammatory cytokines, and pituitary hormones, and insulin resistance. In addition, increased catecholamine levels may exacerbate postoperative outcomes, especially delayed wound recovery, increased cardiovascular and respiratory complications, and immunosuppression. In particular, it is important to reduce the stress response for cancer patients during surgery because they are already immunocompromised status and more vulnerable to perioperative stressful situation. However, there are insufficient results on the benefits of deep neuromuscular block in these patients, although some have reported a reduction of postoperative pain and fewer complications in the deep neuromuscular block compared with moderate neuromuscular block. Therefore, the investigators aim to investigate the difference in the stress response of patients who received conventional moderate neuromuscular block or deep neuromuscular block in robot-assisted gastric cancer surgery.

Inclusion Criteria:

• 1. ASA Ⅰ - Ⅱ patients between 20 and 65 years undergoing robot-assisted gastric cancer surgery

Exclusion Criteria:

• 1. Patients with neuromuscular disease
• 2. Hypertensive patients with β-blockers
• 3. Diabetic patients receiving insulin therapy
• 4. Patients with severe heart (EF <45%), kidney (GFR <60), liver dysfunction (ALT / AST> 100)
• 5. Patients with obesity (BMI ≥30)
• 6. Do not understand Korean language
• 7. For vulnerable subjects who are unable to obtain consent