To explore the correlation between tear metabolomics and POD. The purpose of this study was to compare the results of tear metabolomics between POD and non-POD elderly patients undergoing abdominal surgery, to clarify the correlation between tear metabolomics and POD, and to find tear markers related to POD.

Inclusion Criteria:

• age 65-90 years old;
• ASA I-III;
• patients who plan to undergo elective abdominal surgery under general anesthesia;
• Volunteer to participate in this study and sign informed consent.

Exclusion Criteria:

• patients with known mental illness or lack of communication or cognitive impairment before operation;
• severe vision, hearing, language impairment or other reasons unable to communicate with visitors;
• severe dysfunction of important organs such as heart, brain, lung, liver, kidney, etc.;
• long-term use of sedatives, antidepressants or alcoholism;
• patients with severe postoperative complications and admitted to intensive care unit;
• patients who refused or failed to complete the cognitive function test.
• patients who could not cooperate with the study for any other reason

In the elderly patients who underwent abdominal surgery under general anesthesia, there were no serious systemic diseases and severe cognitive impairment before operation.

The individual participant data for this study is available from the sponsor on reasonable request through email