Evaluation of selective shunt with transcranial Doppler during carotid endarterectomy

Abstract

Objeclive Using transcranial Doppler （TCD） to evaluate the effect of selective shunt （SS） during carotid endarterectomy （CEA）. Methods TCD was used for intraop-erative bilateral middle cerebral artery （MCA） cerebral blood flow continuous monitoring in 169 patients with carotid stenosis treated with CEA. The patients were divided into shunt （n = 32） and non-shunt （n = 137） groups according to whether they performed shunt or not. The open approaches of anterior collateral circulation were recorded. The peak systolic velocity （PSV）, mean velocity （MV）, pulsatility index （PI）, and ratio of MV in bilateral MCA were compared after anesthesia, before and after carotid artery occlusion, before and after shunt, and after carotid artery open. Results MV before carotid artery occlusion in the shunt and non-shunt groups were 34.73±13.54 cm/s and 35.32±13.18 cm/s, respectively, and there was no significant difference （P = 0. 825）. MV in the shunt group after carotid artery occlusion was significantly decreased in the non-shunt group （P =0. 000）. The mean decline rate of MCA MV was 69.34% - 20.93%, and it was decreased more significantly than that in the non-shunt group （P = 0. 000）. The decline rate of MCA MV was increased significantly after shuntoperation, the average increase was 35.68±16.69 cm/s （P = 0. 000）. Conclusions TCD can objectively evaluate the hemodynamic changes before and after shunt operation. Key words: Endarterectomy, carotid; Carotid stenosis; Monitoring, intraoperative; Ultrasonography, Doppler, transcranial; Blood flow velocity