[Combined intraoperative neuromonitoring during carotid endarterectomy].

Abstract

Background: Carotid endarterectomy belongs to the most common vascular operations performed in atherosclerotic lesions of brachiocephalic arteries for prevention of ischemic stroke. One of intraoperative complications of this intervention is ischemic stroke, therefore, currently important remains the task of choosing an optimal technique of intraoperative monitoring and improving methods of preventing the development of ischemic stroke.

Objective: The purpose of this study was to determine an optimal combination of methods of comprehensive intraoperative neuromonitoring during carotid endarterectomy.

Patients and methods: We analyzed the results of treating a total of 206 patients subjected to carotid endarterectomy. The mean age of the patients was 63.9±8.7 years. Depending on the method of intraoperative control over the development of cerebral ischemia, the patients were divided into 2 groups. Group One comprised 97 patients in whom the method of control was the measurement of the retrograde arterial pressure in the internal carotid artery with the calculation of the retrograde arterial pressure index. Group Two was composed of 109 patients in whom the control method consisted in measuring the retrograde arterial pressure and comprehensive intraoperative monitoring.

Results: By the main parameters, the patient groups were comparable (p>0.05). The frequency of developing ischemic stroke amounted to 4.1 and 0.9% in Group One and Group Two, respectively (p=0.048). An intraluminal shunt was used significantly more often in Group Two (with intraoperative monitoring), i. e., in 26.5% (28 patients) vs 12.4% (12 patients) in Group One (without intraoperative monitoring) (p=0.025). The predictive model of reposition of an intraluminal shunt based on the data of intraoperative monitoring: somatosensory evoked potentials + transcranial dopplerography + electroencephalography and intraoperative monitoring: somatosensory evoked potentials + transcranial dopplerography was assessed by means of the ROC analysis and demonstrated comparable parameters of sensitivity and specificity (83%). Therefore, the protocol of intraoperative monitoring with the use of an intraluminal shunt was reduced to assessing alterations in 2 diagnostic parameters (somatosensory evoked potentials + transcranial dopplerography).

Conclusion: Combined neuromonitoring during carotid endarterectomy under conditions of general anesthesia makes it possible to verify critically decreased cerebral perfusion and to determine intraoperative indications for placing an intraluminal shunt and assess its condition during the main stage of surgery, thus resulting in a decrease in the frequency of neurological complications.