Seizures After Cardiac Surgery -- A Study With Continuous EEG Monitoring

• Frequency of non-convulsive seizures in postoperative cardiac surgery patients [ Time Frame: Immediate postoperative monitoring with continuous EEG ] [ Designated as safety issue: No ]
  Immediately after surgery, while still sedated and in the cardiac surgery recovery unit, 9 sticker electrodes will be applied to the skin just below the hairline, which record brain activity onto a computer. The EEG will be recorded for 24 hours. This brain activity (EEG) will later be interpreted by a neurologist who will be looking for evidence of seizure activity in the brain waves. Other relevant information: age, sex, the nature of other health problems, drugs used, complications and whether or not seizures are found will be stored on our computer for further evaluation.
  
  

Background: Most patients do not have any neurological complications after cardiac surgery, but fewer than 1% may have a seizure (abnormal brain activity), with or without a convulsion. This can be due to a reaction to certain types of drugs or less commonly stroke or inflammation. Some seizures in post-operative and intensive care unit patients do not result in convulsions, but rather the abnormal brain activity simply causes confusion or unresponsiveness. The incidence of this type of "nonconvulsive"seizure after cardiac surgery is unknown.

Purpose of the study: The aim of this study is to determine the frequency of nonconvulsive seizures after cardiac surgery using an electroencephalogram or EEG, which records brainwaves through the scalp.

Design of the study: The investigators target is to enroll 150 patients undergoing cardiac surgery. The investigators are including patients greater than 18 years of age who are admitted to the CSRU immediately after cardiac surgery. Included patients are of normal mentation and are able to give their own consent. The investigators will exclude only those patients for whom technical issues prevent us from recording the EEG.