Post Operative Cognitive Recovery and Neuropsychological Complications After General Anesthesia. A Comparison Between Different Techniques of Anesthesia: A Multi-Center Observational Study

The rationale for this study comparing different types of anesthetic maintenance is based on the amount of systemic metabolic breakdown and the low repartion rates within the various tissues and the very rapid elimination of desflurane in respect to the other common inhalation and intravenous anesthetics as possible factors in the rate of recovery of cognitive function and the appearance of post operative delirium. After general anesthesia with desflurane there is less residual hypnotic agent for elimination in the circulation and tissue with respect to the amount given than with propofol or sevoflurance (1-3).

Perioperative cerebral injury correlated with surgical intervention and anesthesia can result in a decline in cognitive function (4) defining the entity of post operative cognitive dysfunction (POCD).

In this study it is possible to distinguish:

• Early POCD: attributable to anesthesia
• Long-Term POCD: could be attributable to of cognition associated with advanced age rather than to procedural effects (surgery, anesthesia, or confinement to a hospital bed)

The prevalence of POCD is higher in patients with advanced age (>70) and in cases where general anesthesia is used for highly invasive surgery (orthopedic, abdominal and thoracic surgery) (5-7). A consensus does not exist regarding tests for evaluation of POCD. In this protocol we propose to use three scales concurrently that are commonly used for evaluation of cognitive function.