Abstract
Even in an age of contracting medical resources, intraoperative EEG monitoring is gaining increasing acceptance as a tool to identify the need for intervention. However, central nervous activity is characterized by very rapid fluctuations. Neurologic injury can happen so quickly that most tests of cerebral well-being do not give useful information in time to intervene. Offline processing techniques for sophisticated derivation of EEG parameters are too slow to provide effective monitoring. To be effective, monitors must be able to detect a change soon enough for something to be done immediately; even 2 h later is too late.