With the increasing geriatric population, age-related physiological changes and common comorbidities increase the risk of surgical and anesthesia-related complications in this patient group. Therefore, careful planning of anesthesia management and ventilation strategies is crucial to achieve safe and successful clinical outcomes. Positive end-expiratory pressure (PEEP), one of these strategies, should be applied with careful consideration of the balance between ensuring oxygenation and maintaining cardiovascular stability in geriatric patients. Early detection of hypoperfusion during the intraoperative period is also an important part of perioperative management. To this end, near-infrared spectroscopy (NIRS) is used as a noninvasive monitoring method to assess cerebral oxygenation, while the perfusion index (PI) is used to evaluate peripheral circulation, providing clinicians with valuable information for predicting potential complications. However, one of the most important neurological complications that can occur after surgery in geriatric patients is postoperative cognitive dysfunction (POCD). The Mini-Mental State Examination (MMSE) is widely preferred for assessing cognitive function during the perioperative period due to its ease of application and reliability.
The primary objective of this study is to investigate the effects of different PEEP levels on PI in geriatric patients undergoing laparoscopic cholecystectomy and to reveal changes in neurocognitive function by comparing preoperative and postoperative MMSE scores. Our secondary objectives are to evaluate the effects of PEEP on NIRS values and to analyze the possible relationships between NIRS, PI, hemodynamic parameters, and MMSE scores.