This study aims to clarify the preventive effect of perioperative liraglutide application on postoperative delirium in elderly patients with Type 2 diabetes undergoing cardiac surgery.

Delirium is the most prevalent neurological complication following cardiac surgery. It is characterized by an acute and fluctuating disturbance in consciousness, attention, and cognitive function. The incidence of delirium post-cardiac surgery ranges between 11% and 46%. It is closely linked to increased postoperative mortality, extended hospital stays, higher healthcare costs, and long-term cognitive impairment. Currently, it is widely recognized that the development of delirium is influenced by multiple factors, including advanced age, diabetes, surgical and anesthetic techniques, depression, baseline cognitive function, and infections, among others.

Inflammatory responses, crucial for protecting against external or internal threats, can, following surgery, lead to neuroinflammation and neurological damage due to elevated postoperative inflammatory markers and blood-brain barrier disruption. The involvement of microglia and astrocytes, key players in the central nervous system's immune response, has been identified in mediating postoperative delirium, making them potential targets for prevention.

Liraglutide, a Glucagon-like peptide-1 receptor agonist primarily used for treating Type 2 diabetes, has shown promise in mitigating neurocognitive damage associated with diabetes and Alzheimer's disease, suggesting its potential in preventing postoperative delirium in cardiac surgery patients with Type 2 diabetes. Preliminary animal studies and a randomized controlled trial indicate that perioperative liraglutide application could reduce the incidence of postoperative delirium by inhibiting glial activation and the subsequent neuroinflammatory response. However, differences in patient demographics, disease severity, and dosing in previous studies highlight the need for further investigation.

The study aims to investigate whether the perioperative administration of liraglutide can prevent the onset of postoperative delirium in elderly patients with Type 2 diabetes undergoing cardiac surgery. Secondary objectives include assessing the impact on the severity and duration of delirium, cognitive function, anxiety, depression, cardiac function, cardiovascular events, ICU stay, mechanical ventilation duration, and levels of serum markers for brain injury, inflammation, myocardial damage, and cardiac function.

Inclusion Criteria:

1. Age ≥ 60 years
2. Type 2 diabetes
3. Patients undergoing elective cardiac surgery

Exclusion Criteria:

1. History of neurological or psychiatric disorders, such as schizophrenia, epilepsy, Parkinson's disease, severe dementia, etc
2. Patients with communication difficulties, such as severe visual, auditory, or speech impairments
3. History of central nervous system damage or surgery
4. Cardiac function NYHA Class IV
5. Severe liver dysfunction (Child-Pugh Class C)
6. Severe renal failure requiring renal replacement therapy
7. History of pancreatitis
8. Type 1 diabetes
9. Patients whose blood sugar is difficult to control within 4-8 mmol/L during the screening period
10. Patients with medullary thyroid carcinoma or a family history of it
11. Pregnant or breastfeeding women
12. Intolerance or allergy to liraglutide
13. Previous use of GLP-1A and SGLT2i
14. Patients who refuse to sign the informed consent