Cognitive disorders common in the post-operative period, are the post-operative delirium (POD) and the post-operative cognitive dysfunction (POCD). The Diagnostic and Statistical Manual of Mental Disorders (DSM) does not mention POCD as a separate disease entity, and thus little is known about the pathogenesis of this disorder. The aim of this study was to review, detect and highlight the most important data cited, regarding pathogenesis mechanisms and treatment of the post-operative cognitive dysfunction (POCD). The study was carried out from March 2015 to June 2015. Literature review was achieved by searching a number of bibliographic databases including PubMed, Google Scholar and SCOPUS, surveying published articles from 1955 to 2014. As far as the selection criteria, the material consists of scientific articles published mainly over the last fifteen years, while material published before 2000 was selected because it was considered to be important. This review showed that deficits are observed in one or more discrete areas of the patient’s mental state, such as attention, concentration, memory, psychomotor speed and more. This condition is usually developed over a period of more than a week or month after surgery and is more common in elderly patients. Mechanisms that have been proposed to explain this phenomenon are hyperventilation, hypotension, cerebral microemboli and inflammatory mechanisms. Its differential diagnosis will be made mainly from delirium. POCD treatment will first include the exclusion of any other serious diseases that can cause organic psychosyndrome and then focus on the actual symptoms.

Cardiac operations which require Cardiopulmonary bypass (CPB) are considered the most common procedures in cardiac surgery, performed for more than half a century, especially in Europe and North America. Despite that new technologies are being incorporated in CPB as long as the development of new techniques in CPB, some debates still remain. These debates regard the achievement of the needed optimal perfusion during CPB and the relation between perfusion pressures and the optimal blood flow during extracorporeal circulation. Blood flow and blood pressure during Cardiopulmonary bypass are very important factors. Although more studies are in favor of a minor superiority of the optimal blood flow requirements, compared to the corresponding optimal blood pressure needs, their role is quite interdependent. The usage of contemporary electronic Data Management Systems (DMS) led to a significant evolution of the perfusion science. Adequate perfusion can now be judged by its results in real time, while information from DMS, such as venous saturation, levels of haemoglobin and lactate, may be used as the markers of optimal perfusion and additionally for the development of the perfusion protocols in the future.

Background: Many studies have shown that a large number of patients undergoing surgery show a measurable cognitive deterioration after surgery, while many of them still show cognitive deficits even three months later an operation. These specific cognitive deficits in which there is a temporal association between surgery and mental disorders are defined as postoperative impairment of cognitive function. Among cognitive disorders occurring during the postoperative period, the post-operative cognitive dysfunction (POCD) is less studied.Aim: Risk factors concerning POCD will be overviewed in order to be considered as a measure of prevention of POCD.Method: A literature search using combined keywords was undertaken on bibliographic databases including PubMed, Google Scholar and Scopus and through systematic selection 72 scientific articles were identified. Concerning the selection criteria, the material of this study consists of sources published mainly over the last fifteen years, while some articles that published before 2000 were selected because they were considered to be important.Results: These disorders frequently occur in patients of advanced age. It is obvious that as the population of humanity ages, many older people are likely to develop health problems that require surgery and therefore a large number of people are likely to develop post-operative cognitive disorders. For the appearance of POCD, as for other mental disorders (e.g. delirium), several factors are implicated. According to the findings, except the advanced age, genetic polymorphism, idiosyncratic condition, the presence of metabolic syndrome and neurological diseases, the type of anaesthesia and surgical operation and sleep disturbance are among the most important risk factors.