Low-Flow Desflurane Anesthesia and Its Effects on BIS and Postoperative Cognitive Functions

This study investigates the effects of low-flow desflurane anesthesia in adult patients undergoing major abdominal surgery. The researchers will examine whether different low-flow strategies: Cause differences in the Bispectral Index (BIS), which measures brain activity during anesthesia, Affect postoperative cognitive functions such as memory and attention. Participants will: Receive desflurane anesthesia during surgery, Have anesthesia delivered at different low-flow rates, Have their BIS values monitored throughout the operation, Complete tests after surgery to evaluate their cognitive functions. This research will help determine the safety of different low-flow strategies and their impact on patients' cognitive recovery after surgery.