Effect of Low-dose Esketamine on Postoperative Depression in Patients With Breast Cancer

Inclusion Criteria: * (1) Female patients who planned to undergo unilateral modified radical mastectomy in breast surgery; (2)Years of education ≥5 years,American Society of Anesthesiologists Ⅰ-II grade; (3) All patients undergoing surgery within 1 week after diagnosis of breast cancer, and do not receive preoperative radiotherapy or chemotherapy; (4) All the patients were married and had children, and were mainly cared for by their immediate family members after surgery. Exclusion Criteria: * (1) Antidepressant treatment was received within the last 2 months; (2) previous personality disorder, intellectual retardation, brain injury or brain disease, combined with schizophrenia, mania and other mental diseases; (3) Preoperative patients with hyperthyroidism or hypothyroidism, severe cardiovascular disease, diabetes, severe blood deficiency, and abnormal heart, lung, liver, and kidney functions; (4) with diseases of the immune system, or use drugs that have obvious effects on the immune system; (5) Pregnancy or lactation;