The aim of the present study is to investigate whether in non-cardiac surgery the frequency of POD after intraoperative undeliberate cerebral saturation could be modulated by the choice of the anesthetic strategy (Volatile Induction and Maintenance of Anesthesia [VIMA] and Total Intravenous Anesthesia [TIVA]). Based on our previous data we hypothesized that incidence of POD would be lower with VIMA compared to TIVA.