Abstract
CORONARY ARTERY BYPASS GRAFTING (CABG) surgery has been associated with different neurologic complications such as intracerebral hemorrhage, seizures, delirium, cognitive impairment, and peripheral neuropathy.
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Specifically, the incidence of seizures after cardiac surgery varies between 0.5% and 7.6%.
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Seizures are due mainly to thromboembolic ischemic stroke, cerebral air embolism, or specific drugs.
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When seizures occur, recurrence rates range between 40% and 66%, and an association with an abnormal outcome has been reported. Diagnosis of nonconvulsive seizures (NCS) often is elusive and frequently is missed in the cardiac surgery intensive care unit (ICU) setting. NCS are difficult to diagnose because they require the following: (1) a high degree of clinical suspicion, especially in patients with prolonged unresponsiveness or confusion without a better explanation; (2) recognition of subtle clinical signs (eg, nystagmus and face/hand twitching); and (3) availability of continuous electroencephalographic (EEG) monitoring, recorded for at least 24 hours. Electrocardiography (ECG) is a commonly used diagnostic tool for seizure detection and has been confirmed to be clinically relevant by using heart rate variability (HRV) analysis.
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HRV is defined as the beat-to-beat variation in either heart rate (HR) or the duration of the RR interval in the beat-to-beat interval of the heart, and recent advancements in the analysis of HRV in epilepsy have revealed that epileptic seizures are accompanied by changes in various autonomic functions such as HR, which might help to unravel the causes of sudden unexpected death in epilepsy.
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