Abstract
Brain injury after cardiovascular surgery is associated with significantly reduced prognosis. The ability to predict and prevent brain injury during the perioperative period is thus important. There are two categories of brain damage after cardiac surgery: type 1, focal neurologic deficits, coma and stupor; and type 2, decline in intellectual function and memory impairment. These types have an incidence of 3.1% and 3.0%, respectively. With both types, mortality rates are increased. Important risk factors for brain injury after cardiovascular surgery include age, atherosclerosis of the central artery, intraaortic balloon pumping, diabetes mellitus, lung disease and alcohol abuse.
Cardiopulmonary bypass (CPB) can induce brain injury after cardiovascular surgery, as CPB can evoke embolization, low perfusion rates and inflammatory response. As off-pump coronary artery bypass graft (OPCAB) significantly inhibits embolization and inflammatory response, we consider OPCAB to protect against brain injury after surgery. However, many reports suggest that these considerations are insufficient in low-risk patients.
In aortic arch replacement, it is important to protect against cerebral ischemia during revascularization of the cervical artery. Methods of brain protection for aortic arch replacement include deep hypothermic circulatory arrest, selective antegrade cerebral perfusion and retrograde cerebral perfusion. These methods are selected according to patient risk and the policy of the specific institution. The optimal methods for brain protection remain unclear.
