Effect of Hypothermia on BIS and PSI Correlation During Cardiopulmonary Bypass

The goal of this observational study is to evaluate whether hypothermia affects the relationship between electroencephalography-derived indices during cardiac surgery in adult patients undergoing cardiopulmonary bypass. The main questions it aims to answer are: Does the correlation between Bispectral Index (BIS) and Patient State Index (PSI) change between normothermic and hypothermic phases during cardiopulmonary bypass? How do BIS and PSI values change in response to decreasing body temperature? Participants will: Undergo standard general anesthesia for elective on-pump coronary artery bypass surgery Be monitored simultaneously with BIS and PSI devices during surgery Have data recorded at predefined temperature-based time points during cardiopulmonary bypass

Inclusion Criteria: * Age ≥18 years * Elective on-pump Coronary Artery Bypass Grafting (CABG) surgery * Planned use of general anesthesia * Written informed consent Exclusion Criteria: * Preexisting neurological disease * Use of medications affecting Electroencephalography (e.g., antiepileptics) * Severe hepatic dysfunction * Emergency surgery * Inadequate signal quality for anesthesia depth monitoring