70 patients with hip fractures were randomized to receive either general anesthesia combined with fascia iliaca compartment block (FICB; n=35) or general anesthesia alone (n=35). The primary outcome of interest was heart rate variability (HRV) at various perioperative time points. Secondary outcomes included mean arterial pressure, heart rate, visual analog scale (VAS) scores, doses of oral pain medication over 24 hours, and patient satisfaction scores. Outcomes were assessed at admission to the operating room, during positioning, at skin incision, 30 minutes after the start of surgery, and 6 hours postoperatively. Overall, the results of the study revealed that the FICB group had significantly reduced HRV indicators and lower heart rates at several perioperative time points, alongside lower postoperative pain scores and analgesic requirements. The findings suggest that ultrasound-guided FICB can effectively manage perioperative pain and autonomic function in elderly hip fracture patients.