Mecanismo da Circulação Extracorpórea e Eventos Neurológicos em Cirurgia Cardíaca

Abstract

Introduction: Neurological complications after cardiac surgery are, following cardiac complications, the responsibles for the great morbidity and mortality still observed in this type of surgery. However, the underlying mechanisms and effective prevention measures are still unknown. Extracorporeal circulation was, from the beginning of its use, pointed as the principal cause. The objective of this paper is to describe the development and the mechanism of cardiopulmonary bypass and the main neurological complications associated with cardiac surgery, including pathophysiological mechanisms and possible prevention measures. Material and Methods: Review of the literature on the evolution of cardiopulmonary bypass, its fundamental role for cardiovascular surgery and the complications associated with cardiac surgery. Results: The process of development and application of cardiopulmonary bypass was a fundamental advance that allowed open heart surgery, considered as one of the most important clinical advances of medicine of the twentieth century. Since the beginning of its application, the incidence of neurological complications has been object of concern and numerous attempts to reduce it have been made. Currently, it is known that its occurrence is related to the cardiac surgery itself and not only to the cardiopulmonary bypass, having a multifactorial aetiology. Complications include stroke, neuropsychiatric disorders and peripheral neuropathies. Discussion and Conclusion: Cardiopulmonary bypass has progressed steadily and safely over the last decades since its conception by Gibbon, in 1953. Despite its evolution and all the procedures performed in an attempt to alleviate the complications, there is still a significant risk of adverse neurological effects during cardiac surgery. Therefore, more studies are necessary to be able to describe, with more certainty, the mechanisms underlying these complications, in order to improve all perioperative care of the patient. Currently, one of the foci is the possible genetic role in the pathophysiology of the lesions. This risk also highlights the importance of the application of preventive measures and the fundamental role of the surgeon, anaesthesiologist and perfusionists and teamwork, since these neurological complications can have catastrophic results.