Summary:

Postoperative delirium is a highly prevalent disease (10-30% prevalence) after surgery in intensive care unit, however, it is often misdiagnosed and mistreated. The aim of the present project is to investigate risk factors for postoperative delirium in more detail, to evaluate respective cognitive test systems and to measure EEG activity parallel to patients' serum anticholinergic activity. The pathophysiology of delirium is unknown up to now: a possible dysbalance between cerebral acetylcholine and dopamine concentrations is a likely hypothesis. Therefore, the measurement of peripheral serum anticholinergic activity could be a new prognostic factor for evaluation of delirium. Because delirium is also associated with higher postoperative mortality and morbidity, with delayed functional recovery, and postoperative delirium makes patient management much more difficult, increases costs, and, above all, causes severe discomfort to the patient new interdisciplinary diagnostic strategies are necessary to resolve this problem.

Inclusion Criteria:

• All patients at Intensive Care Unit over a defined time period
• Over 18 years old

Exclusion Criteria:

• Elective heart and vascular patients