The aim of this pilot study is to establish a correlation between perioperative heart rate variability (HRV) as an expression of the shift in the balance of the autonomic nervous system and the occurrence of postoperative inflammation and delirium. The main question it aims to answer is: Do patient with increased sympathetic nervous system activity develop postoperative delirium (POD) more often than patients with increased parasympathetic tone?
> 50 years of age
Scheduled for elective moderate to major risk traumatology or orthopedic surgery (excluding spine surgery) and anticipated duration of general anaesthesia ≥ 60 minutes.
Delirium before surgery.
Patients with emergency surgery
Contraindication to general anesthesia
ASA ≥ 4.