Postoperative cognitive dysfunction (POCD) is a common postoperative complication in patients aged 65 and over, which refers to cognitive function changes such as memory decline and attention deficit after anesthesia and surgery. In severe cases, personality changes and social behavior decline may also occur, resulting in irreversible cognitive impairment.Previous studies have suggested that cognitive dysfunction after general anesthesia is linked to a genetic disorder of the body clock.Exosomes are cellular forms of cellular microvesicles containing complex RNA and proteins.Exosomes can mediate the expression of genes in the late transcriptional period of the clock system, and directly or indirectly participate in the negative regulation of rhythm expression of minute control genes, playing an important role in the intercellular circadian rhythm information output pathway.Rhythm disorders in the core biological clock system of urinary exosomes and the clock control genes related to kidney can early indicate circadian rhythm changes in the core biological clock system.The sorting and detection of urinary exosome clock information materials in patients has the advantages of easy access, continuous monitoring, early diagnosis and less damage, making urinary exosome a biomarker for the diagnosis and monitoring of circadian rhythm of a good kidney biological clock system.

Inclusion Criteria:

• patients whose age ≥ 18 years old and <90 years of preoperative sleep disorder;
• Primary cancer patients who had not received any radiotherapy or chemotherapy before surgery;
• Surgeries expected to be performed under general anesthesia after ≧3 hours

Exclusion Criteria:

• a history of schizophrenia, epilepsy, Parkinson's disease, or myasthenia gravis;
• inability to communicate due to coma, severe dementia, language impairment or serious illness;
• critically ill (preoperative ASA (American Society of Anesthesiologists)>III), Childe-Pugh C or severe renal insufficiency (preoperative dialysis);
• Neurosurgery.