This study looks at memory problems after surgery in people with liver disease. We want to know how often these problems happen and what might cause them. The main question it aims to answer is:

1. Do people with liver disease have more memory problems after stomach surgery than people without liver disease? If yes, how much more often?
2. Are changes in stomach bacteria and body chemicals related to these memory problems?

Who can join:

• Adults getting stomach surgery
• Both people with and without liver disease

What participants will do:

• Take memory tests before and after surgery
• Give stool (poop) and blood samples before and after surgery

Why this matters:

Memory problems after surgery can make recovery harder. If we find that stomach bacteria or body chemicals are involved, doctors might find new ways to prevent these problems in people with liver disease.

Liver cirrhosis is one of the most prevalent global diseases, ranking as the 11th leading cause of death worldwide with approximately 1 million annual fatalities. China has an estimated 300 million patients with liver diseases, including 7 million cirrhosis cases, accounting for 11% of global cirrhosis-related mortality. Previous studies report that approximately 1 in 10 cirrhosis patients require hepatic or non-hepatic surgical interventions during their final two years of life. With advancements in perioperative techniques including surgery, anesthesia, critical care, and nursing, non-hepatic surgeries for cirrhotic patients have become increasingly common.

The major postoperative complications in cirrhotic patients include coma, hepatic failure, sepsis, hemorrhage, thrombosis, and renal failure, among which coma represents the most frequent complication. These findings highlight the critical scientific importance of reducing postoperative complications in cirrhotic patients, particularly neurological complications.

Postoperative delirium (POD) refers to delirium occurring within one week after surgical procedures, with characteristic temporal features predominantly manifesting 24-72 hours postoperation. POD adversely impacts both short- and long-term patient outcomes. Studies demonstrate that POD patients face 2-3 times higher risk of other postoperative complications, 2-3 times increased perioperative mortality risk and prolonged hospitalization. Long-term follow-up studies reveal that POD patients exhibit increased incidence of postoperative cognitive dysfunction, reduced quality of life and higher long-term mortality rates. Cirrhotic patients frequently present with overt or subclinical cognitive impairment. Surgical intervention in this population may exacerbate neurological dysfunction, potentially explaining the significantly elevated risk of postoperative neurological complications. The commonly observed gut microbiota dysbiosis and metabolic disturbances in cirrhotic patients may play pivotal roles in this process.

This study aims to compare POD incidence and perioperative cognitive function changes between cirrhotic and non-cirrhotic patients undergoing upper abdominal surgery, and investigate the role of gut microbiota dysbiosis and metabolic abnormalities in POD pathogenesis among cirrhotic patients through integrated microbiome-metabolome analysis. The findings may provide valuable insights into the mechanisms and potential therapeutic approaches for cognitive dysfunction in cirrhotic patients.

Inclusion Criteria:

1. Age: 18-80 years
2. Patients with or without liver cirrhosis scheduled for upper abdominal surgery due to various clinical indications
3. Ability to comply with the study protocol and provide informed consent

Exclusion Criteria:

1. Comorbid severe cardiac, pulmonary, or renal diseases

2. Patients with mental status incompatible with study participation, including:

   • Psychiatric disorders
   • Inability to communicate clearly

3. Any condition preventing effective communication or cooperation

Hospitalized patients scheduled for surgical treatment at Sichuan Provincial People's Hospital.

If the subsequent metabolomics or gut microbiome analyses yield particularly significant findings, these data may initially remain unpublished as they could require further validation through basic animal experiments.