The Effect of Bupivacaine Liposome Preemptive Analgesia on Postoperative Pain and Delirium in Elderly Patients Undergoing Hip Fracture Surgery

Inclusion Criteria: * Patients with hip fractures scheduled for surgical treatment (including femoral neck fractures, intertrochanteric fractures, and fractures more than 5 cm below the lesser trochanter of the femur). * Age ≥65 years. * American Society of Anesthesiologists (ASA) grade I - III. * The patient or family member signed the informed consent form Exclusion Criteria: * Compound injuries (such as combined fractures of the head, chest, pelvis, or limbs). * Have a clear history of mental illness or are taking psychotropic drugs. * Preoperative delirium or the use of delirium-related medications (such as olanzapine). * A history of acute cerebrovascular disease (cerebral infarction or cerebral hemorrhage) within 6 months. * Patients requiring sedation or postoperative coma due to the condition. * Allergy to amide local anesthetics. * Severe arrhythmia or liver or kidney dysfunction