Electroencephalographic Changes in Carotid Endarterectomy Correlated with Ischemia

Continuous electroencephalography (cEEG) is increasingly employed for real-time monitoring of brain activity, particularly for detecting cerebral ischemia, a condition caused by reduced blood flow to the brain. In carotid endarterectomy (CEA) surgeries, neurophysiologists visually monitor the cEEG for significant changes in the frequency and amplitude of the waveforms. Due to the tedium of prolonged visual monitoring, quantitative EEG (QEEG) parameters that quantify various aspects of the electroencephalogram, such as frequency, amplitude, and power, have been developed to aid visual analysis. We investigated the utility of ten QEEG parameters in detecting cerebral ischemia during CEA using a database of 1551 patients who were monitored with intraoperative EEG. Our findings indicate a statistically significant decrease in the trough values in all ten QEEG parameters when there were visual changes in the EEG. Furthermore, our findings show that women are more likely than men to experience ischemia during CEA, with the odds of an ischemic change being nearly twice as high in women.