Although the acute and chronic postoperative pain of surgical patients has gradually been paid attention to, it has not yet been better resolved.and, the incidence of anxiety and depression in cancer patients is constantly increasing，The new analgesic anesthetic esketamine hydrochloride was launched in China last year，however, in the domestic and foreign literature, there are still few reports of esketamine hydrochloride in postoperative analgesia, and most of them are retrospective and small samples.This study aims to investigate whether esketamine has advantages over traditional opioids in terms of postoperative analgesia, anxiety and depression in cancer patients.

Inclusion Criteria:

• Age ≥18 years old;
• Patients undergoing elective tumor surgery
• Use intravenous analgesia pump (PCIA) after operation

Exclusion Criteria:

• Patients with severe infection or respiratory system diseases;
• Severe arrhythmia, unstable angina or myocardial infarction, heart failure;
• Patients with severe diseases of liver, kidney, endocrine or immune system; ·Patients with fever before operation;
• One month before operation Patients receiving chemotherapy, radiotherapy or immunotherapy;
• Drug or alcohol dependence;
• Mental illness, disturbance of consciousness and communication difficulties or inability to understand the questionnaire or refusal to complete;
• Long-term use of antidepressant and anxiety drugs;
• High intracranial pressure High intraocular pressure