Cardiopulmonary bypass in cardiac surgery

Cardiopulmonary bypass (CPB) is a standard procedure in cardiac surgery; however, apart from its therapeutic options a CPB might also initiate systemic and organ-specific complications, such as heart failure, renal and pulmonary dysfunction, impaired coagulation as well as neurological and cognitive dysfunction. The immunological response to the extracorporeal circulation generates systemic inflammation which often meets the definition of systemic inflammatory response syndrome (SIRS). The main inducers of SIRS are contact of blood with the artificial surfaces of the CPB, mechanical stress which affects the blood components and the extensive surgical trauma. Hence, a number of technical and surgical developments aim at reduction of the inflammatory response caused by the CPB. By reason of surgical demands, the majority of cardiothoracic procedures still depend on the use of CPB; however, there is an on-going development of new techniques trying to reduce the surgical trauma and the negative consequences of CPB. Here, minimized systems with biocompatible surfaces have been shown to be effective in attenuating the inflammatory response to CPB. Alternative procedures such as off-pump surgery may help to avoid CPB-associated complications but due to specific limitations will not replace conventional bypass surgery.