Tehran University of Medical Sciences Archives of Anesthesiology and Critical Care 2423-5849 0 0 2025 12 02 1315 1315 Natalina Manalu Department of Anaesthesia, Intensive Care and Pain Management, Hasanuddin University, Makassar, Indonesia. Syafruddin Gaus Department of Anaesthesia, Intensive Care and Pain Management, Hasanuddin University, Makassar, Indonesia. & Department of Anaesthesia, Intensive Care and Pain Management, Dr. Wahidin Sudirohusodo General Hospital, Makassar, Indonesia. Syamsul Salam Department of Anaesthesia, Intensive Care and Pain Management, Hasanuddin University, Makassar, Indonesia. & Department of Anaesthesia, Intensive Care and Pain Management, Dr. Wahidin Sudirohusodo General Hospital, Makassar, Indonesia. Andi Salahuddin Department of Anaesthesia, Intensive Care and Pain Management, Hasanuddin University, Makassar, Indonesia. Muhammad Rum Department of Anaesthesia, Intensive Care and Pain Management, Hasanuddin University, Makassar, Indonesia. Madonna Datu Department of Anaesthesia, Intensive Care and Pain Management, Hasanuddin University, Makassar, Indonesia. & Department of Anaesthesia, Intensive Care and Pain Management, Dr. Wahidin Sudirohusodo General Hospital, Makassar, Indonesia. 2025 06 15 2025 07 10 Background: The incidence of postoperative delirium (POD) in geriatric patients is aged 3-61%. The combined effects of inflammatory factors and depth of anesthesia can affect neurotransmitters and receptors in the central nervous system that affect POD. To analyze the relationship between depth of anesthesia and IL-6 with the incidence of POD in geriatric patients undergoing general anesthesia. Methods: A prospective cohort study was conducted in geriatric patients undergoing general anesthesia. Patients were divided into two groups based on the bispectral index (BIS): BIS 40-45 and BIS 51-60. POD was measured using the Confusion Assessment Method (CAM) and Mini-Mental State Exam (MMSE) 24 hours postoperatively. Serum IL-6 measurements were also performed before and 24 hours postoperatively. Results: A total of 22 patients were collected with the results that the MMSE score decreased insignificantly at 24 hours postoperatively, and there was no difference in MMSE scores based on BIS (p > 0.05). The depth of anesthesia was significantly associated with CAM (p < 0.05). Delirium incidence was more frequent in BIS 40-45. IL-6 levels increased significantly at 24 hours postoperatively (p < 0.05). IL-6 levels were not significantly associated with MMSE and CAM scores (p > 0.05). Conclusion: BIS 40-45 has the potential to be a predictor of POD in geriatric patients with general anesthesia. https://aacc.tums.ac.ir/index.php/aacc/article/view/1315