Application Of Dexmedetomidine Hydrochloride In Carotid Endarterectomy

Objective To investigate the effect of dexmedetomidine hydrochloride in carotid endarterectomy on cerebrovascular reactivity,and to analyze the preventive effect of dexmedetomidine hydrochloride on cerebral hyperperfusion syndrome and vascular cognitive dysfunction.Methods 60 patients with carotid endarterectomy who were admitted to our hospital from January 2019 to December 2020 were randomly divided into two groups:control group and dexmedetomidine group（n=30）.In the dexmedetomidine group,dexmedetomidine was pumped on patients at 10 minutes before anesthesia induction,which dose was 1.0ug/kg,and dexmedetomidine was continuously infused after anesthesia induction,which dose was 0.40ug/kg/h.Dexmedetomidine was withdrawn40 minutes before the end of operation.After anesthesia induction,propofol and remifentanil were given for anesthesia maintenance;patients in the control group were not given dexmedetomidine,and other anesthesia methods were the same as those in the dexmedetomidine group.The Vs（Systolic cerebral blood flow velocity）,Vd（Diastolic cerebral blood flow velocity）,Vm（Mean cerebral blood flow velocity）,Dmean（Mean cerebral blood flow velocity decreased index）,PI（Pulsation index）and BHI（Breathless index）of two groups at T₀（before operation）,T₁（when internal carotid artery was blocked）,T₂（when internal carotid artery was opened）and T₃（after operation）were compared,and MoCA scores of two groups before and after operation were compared.Result At T₀time,there was no significant difference on Vs,Vd,Vm,PI,BHI and MoCA scores before operation between the control group and dexmedetomidine group（p>0.05）.At T1 time,Dmean index in the two groups was lower than 100%at internal carotid artery occlusion,and there was no significant difference（p>0.05）.At T2（open internal carotid artery）time point,the Dmean level of both groups was higher than 100%,and the increase degree of the control group was more significant than that of the dexmedetomidine group（p<0.05）.Vs,Vd,and Vm were significantly higher in both groups at T3（postoperative）time point than at T0 time point（p<0.05）.There was no statistically significant difference between the two groups（p>0.05）.Compared with T0 time,the PI values index in two groups decreased,and the dexmedetomidine group decreased more significantly than control group（p<0.05）.Compared with T0 time,the BHI and MoCA scores in the two groups at T3 time increased,and the BHI and MoCA scores in the dexmedetomidine group increased more significantly than those in the control group（p<0.05）.Conclusion The application of dexmedetomidine hydrochloride in carotid endarterectomy can regulate arterial blood flow velocity,reduce the incidence of cerebral hyperperfusion syndrome,improve postoperative cerebrovascular reactivity in patients,and may improve vascular cognitive dysfunction caused by carotid stenosis.