Postoperative cognitive dysfunction.

Postoperative cognitive dysfunction is a severe and life-threatening complication after an operation. The mobilisation of the patient is difficult and, therefore, the stay of the patient in the hospital is extended and the resulting immobilisation is associated with further complications (e.g. decubitus, pneumonia, or thrombosis). The genesis of the postoperative cognitive dysfunction has different causes and the highest risk factors are the age of the patient and the character and the duration of the operation. Preexisting diseases, like diabetes mellitus, heart failure, depression or alcohol excess are high risk factors as well as the use of anticholinergic drugs. A specific therapy for this cognitive dysfunction is unknown and, therefore, preventive measures should be used in patients with a preexisting high risk.