Multimodal Neurophysiological Monitoring Reduces Shunt Incidence during Carotid Endarterectomy

The use of shunt during carotid surgery is controversial. Different experiences are found in literature with transcranial Doppler (TCD), electroencephalogram (EEG), stump pressure (SP), and somatosensorial evoked potentials (SSEP). We realized a retrospective analysis of patients treated with carotid endarterectomy in our unit in the last 2 years. We use several cerebral monitoring: until 2017 we preferred SP + TCD, and, if not available, EEG. Since 2017 we introduced EEG with SSEP, always in association with SP. We analyzed those 2 groups of patients: before and after introduction of EEG with SSEP. From January 2016 to December 2018 we performed 156 carotid revascularizations. In the first group of 93 patients treated under combined SP + TCD (or EEG), we observed 1 stroke (1.1%) and 2 transient ischemic attacks (TIAs) (2.1%); we selectively used a shunt in 21 cases (22.5%). In the second group, 63 patients had an SP + EEG with SSEP monitoring; we observed 1 stroke (1.5%) and 2 TIAs (3.1%), a shunt was necessary in 12 cases (12.9%). In our experience, EEG with SSEP represents an effective parameter to indicate shunt positioning, as we were able to reduce its use, with the same incidence of stroke and TIA.