Computer-derived density spectral array in detection of mild analog electroencephalographic ischemic pattern changes...

Area of Science:

• Neuroscience
• Medical Technology
• Surgical Monitoring

Background:

• Carotid endarterectomy requires continuous monitoring for cerebral ischemia.
• Analog electroencephalography (EEG) is a standard method for detecting ischemic changes.
• Density spectral array (DSA) offers a computer-derived analysis of EEG data.

Purpose of the Study:

• To evaluate the sensitivity and specificity of DSA in detecting EEG ischemic patterns during carotid artery cross-clamping.
• To compare DSA's ability to identify ischemic changes with the severity and type of changes observed in analog EEG.

Main Methods:

• A prospective study involving 103 patients undergoing carotid endarterectomy under general anesthesia.
• Simultaneous monitoring using 16-channel analog EEG and 4-channel DSA.
• Interpretation of DSA and analog EEG data by two independent observers.

Main Results:

• DSA sensitivity for detecting ischemic changes varied between observers (72% and 59%), with high specificity (99% and 96%).
• DSA sensitivity correlated with the severity of ischemic changes, being highest for severe ischemia (95%) and lower for mild ischemia (18-61%).
• High inter-observer reproducibility was noted for both analog EEG (k=0.95) and DSA (k=0.85) changes.

Conclusions:

• Density spectral array is not a reliable substitute for 16-channel analog EEG monitoring during carotid endarterectomy.
• DSA fails to reliably detect mild analog EEG pattern changes indicative of cerebral ischemia.
• Analog EEG remains essential for comprehensive cerebral ischemia monitoring in this surgical context.