[Changes in mental function after anesthesia and surgery]

Minor short-term depression of mental function is seen after anaesthesia and surgery. However, general anaesthesia does not seem to cause permanent damage or depress mental function beyond the first 2-4 postoperative days and no significant advantages of regional anaesthesia, as regards to cerebral function, are found after this period. Severe cases of long term mental deterioration after surgery and anaesthesia may be explained by other factors such as per- and postoperative complications. The risk of mental disturbance is increased in patients with psychiatric disease or presenile dementia and may be due to ongoing treatment with tricyclic antidepressant and neuroleptic drugs. Centrally acting cholinergic drugs, hypotension and hypoxia together with postoperative pain and sleep deprivation should be avoided.