Intraoperative Neurological Monitoring With Evoked Potentials During Carotid Endarterectomy Versus Cooperative Patients Under General Anesthesia Technique: A Retrospective Study

Introduction:The best technique to evaluate contralateral carotid flow during carotid endarterectomy (CEA) is still debated; an accurate detection of efficient contralateral blood flow can avoid unnecessary shunt placement and its complications. The aim of this retrospective observational study was to evaluate and compare the safety and efficacy of general anesthesia with motor-evoked potential and somatosensory-evoked potentials (mSSEP and tcMEP) versus cooperative patients under general anesthesia (CPGA) technique for CEA. Primary outcome was the rate of technical failure. The procedural time and shunt incidence between the 2 neuromonitoring strategies were also analyzed.Patients and Methods:A total of 331 patients who consecutively underwent CEA were included (100 patients in the CPGA group and 231 in the mSSEP+tcMEP group). The anesthesia technique was customized according to the cerebral monitoring needs. Comparison between groups was performed along with risk analysis.Results:Electrophysiological monitoring seems to be a safe and effective strategy of neuromonitoring during CEA. Compared with the CPGA technique, it ensures fewer technical failures, reduces surgical and anesthesiological time and, moreover, it may reduce shunt risk/incidence. The incidence of shunt between the CPGA group and mSSEP+tcMEP was statistically different (CPGA 12%, mSSEP+tcMEP 5.2%; P=0.02), and the relative risk reduction in the mSSEP+tcMEP group, compared with the CPGA group, was 0.57.Conclusions:mSSEP and tcMEP neuromonitoring was associated with less technical failure and procedural time than asleep-awake-asleep strategy. The evoked potential neuromonitoring may be an alternative technique to awake clinical assessment during CEA.