Clinical Research Directory

Inclusion Criteria: * Patients with informed consent Elective planned cases * Patients between the ages of 18-65 * American Society of Anesthesiologists ASA classification ASA 1-2 patients * Surgeries planned to last at least 30 minutes. Exclusion Criteria: * Patients who refuse to participate in the study, * patients who are considered for emergency surgery, * pediatric patients, * patients with peripheral vascular diseases or carotid stenosis, * patients using antidepressants or antipsychotic drugs * those with neurological diseases will be excluded from the study.