Effect of Esketamine on Anxiety State in Patients Undergoing Abdominal Tumor Surgery

Inclusion Criteria:

* Patients undergoing abdominal tumor surgery;
* older than 18 years old and younger than 70 years old;
* ASA grade I-III；
* Hamilton anxiety scale ≥ 8.

Exclusion Criteria:

* Having serious mental illness before surgery or on antipsychotic medication in the two weeks before screening;
* Severe organ function lesions such as heart failure (left ventricular ejection fraction \<30%), myocardial infarction, kidney failure (requiring kidney replacement therapy), liver function impairment (Child-Pugh grade C), etc.
* Patients arranged to receive general anesthesia combined with epidural anesthesia patients;
* Patients who cannot communicate, read or write due to visual, auditory, language or other reasons;
* Patients allergic to ketamine;
* Patients refused to use postoperative self-controlled intravenous analgesia pump;
* Patients refused to participate in the study.