الفهرس 
Incidence of neurological complications after CPBOnly 14 pages are availabe for public view
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Abstract
Neurological complications are an important cause of morbidity and mortality during cardiac operations. Neuropsychological impairment is a well-documented and a very common complication occurring in the majority of the patients in the early postoperative period and in approximately one third of the patients several months after the operation.
Neurological morbidity includes seizures, strokes, post pump choreoathetosis and abnormal cognitive functioning. Cerebral microemboli generated during CABG with cardiopulmonary bypass might be implicated in postoperative neurological impairment.
CABG can lead to serious neurological complications, the incidence of these complications ranges from 0.4 to 5.7% for ischemic stroke, 10 to 30% for delirium, and 33 to 80% for persistent cognitive dysfunction with or without behavioral changes. Recent myocardial infarction (within 24 hours before CABG) was associated with a 3 times higher risk of stroke reported a higher incidence of stroke after recent myocardial infarction. Furthermore, the length of stay in the intensive care unit and hospital ward is longer for patients with neurological complications resulting in a two folds increase in the total cost of care.
The following are some of the risk factors for postoperative complications: Old age, Cardiovascular Risk Factors include (Hypertension and Coronary artery diseases), History of Prior Brain Ischemia, Craniocervical Artery Stenosis, Aortic Arch Atherosclerosis.
Neurological complications could be prevented by preoperative Trans-esophageal echo (TEE), it can guide the ideal surgical approach by detecting the exact location, characteristics and severity of aortic atherosclerosis. TEE helps to select where to place the partial occlusion clamp and aortic cannula and avoiding plaque disruption. Screening for Craniocervical stenosis should be performed in patients considered at high risk for perioperative stroke. Off-pump CABG should be considered for patients with severe proximal arch atherosclerosis, since the technique avoids aortic cross clamping. Intraaortic filters are also under study with the theory that the system may capture and remove aortic embolic material during procedures.
Cardiac surgery is associated with a higher incidence of perioperative seizures owing to severe metabolic, hemodynamic or blood modifications that are induced by cardiopulmonary bypass.
Brain MRI is the diagnostic method and more sensitive than CT for detecting brain ischemia and hemorrhage, In addition to the MRI, an MRA of the Circle of Willis can provide valuable information regarding the patency and collateralization of the intracranial vasculature. An EEG can also provide important clues includes ruling out nonconvulsive status.
Once the diagnosis of acute postoperative encephalopathy (with or without brain ischemia) has been established, the main goals of the medical team are the prevention of further brain ischemia, the prevention and management of medical complications (such as myocardial ischemia, systemic hypotension, acute renal Failure shock liver, infection, deep venous thrombosis and pulmonary embolism), and finally coordination of the initial rehabilitation efforts. When the neuroimaging studies suggest intracranial stenosis or regional brain hypoperfusion, a bolus of normal saline should be immediately administered and all antihypertensive drugs should be withheld if possible.
Treatment of seizures in medically ill patients is aimed at correction of the underlying cause with appropriate short-term anticonvulsant medication, Non-convulsive status epilepticus should be considered in any patient with confusion or coma of unclear cause and electroencephalography should be done at the earliest opportunity.