CONTINUOUS EEG AND EVOKED-POTENTIAL MONITORING IN THE NEUROSCIENCE INTENSIVE-CARE UNIT

As with other methods long used in intensive care units (ICU) and oper ating rooms (OR), the goal of neuroscience ICU continuous EEG (NICU-CE EG) and evoked potential (NICU-EP) monitoring is to extend our powers of observation to detect abnormalities at a reversible stage. EEG is a n appropriate monitoring tool because it is linked to cerebral metabol ism, is sensitive to ischemia and hypoxemia, correlates with cerebral topography, detects neuronal dysfunction at a reversible stage, and is the best method for detecting seizure activity. When applied systemat ically, it can impact medical decision-making in 81% of monitored pati ents. It is useful in monitoring precarious cerebral perfusion at the bedside, and it has revealed that nonconvulsive seizures, undetectable otherwise, occur in 34% of NICU patients. In convulsive status epilep ticus, NICU-CEEG can help avoid undertreatment and overtreatment. In c omatose patients, it can provide useful prognostic information as well as detect potentially treatable causes. Traditional impediments to it s application are yielding to technological advances and educational e fforts. Real-time digitized EEG in particular has been a major advance . Within limits, somatosensory evoked potential monitoring (ICU-SEP) i s useful in the prognosis of coma, but it is less helpful in monitorin g focal cerebral ischemia. Brainstem auditory evoked potential monitor ing has a relatively restricted role in the NICU but is helpful in dis tinguishing structural from nonstructural causes of coma and can suppl ement ICU-SEP in predicting outcome.