Cognitive Dysfunction after Surgery: An Emergent Problem

Postoperative cognitive dysfunction (POCD) results as a large problem that causes a reduction in the quality of life and increases morbidity and mortality especially in elderly patients. The increased age of patients undergoing surgery has made evident the problem and several studies evaluated pathogenesis and implemented a targeted therapy. This review analyses POCD, delirium and mild cognitive impairment (MCI) definition, risk factors and physiopathology with an analysis on anaesthesia technique influence. Unlike the postoperative delirium, POCD is more difficult to diagnose because of several tests that must be administered in the pre and postoperative period, even at a distance of time. Furthermore adequate depth of anaesthesia, monitored with Bispectral Index (BIS) or Electroencephalography (EEG), reduces the cognitive dysfunction incidence. Currently the pathogenesis is not well understood although neuro inflammation plays a central role while the importance of anaesthesia techniques has not established.