Cerebral protection during carotid endarterectomy--EEG monitoring as a guide to the use of intraluminal shunts.

The authors have reviewed the literature concerning measures for cerebral protection during carotid endarterectomy, with particular reference to the controversy regarding the use of an intraluminar shunt. The authors use preoperative EEG analysis during the carotid compression test as well as intraoperative EEG monitoring, and insert a shunt only when signs of cerebral ischaemia appear. This approach was used in 100 patients during a 4 year period and an internal shunt was required in only 10% of these patients. The mortality was 1% and morbidity 1% in this series. The authors believe that EEG monitoring is a reliable technique in detecting signs of cerebral ischaemia before irreversible changes occur and that an intraoperative shunt should be used only when necessary, and not routinely, as it may contribute to operative and postoperative complications.