Effects Of Goal-directed Fluid Therapy On Cerebral Oxygen Supply-demand Balance In Patients Undergoing Carotid Endarterectomy

Objective:To evaluate the effects of goal-directed fluid therapy（GDFT）on cerebral oxygen supply-demand balance in patients undergoing carotid endarterectomy（CEA）.Methods:We included 48 patients underwent CEA from January 2020 to January 2021.They were randomly divided into two groups:the goal-directed fluid therapy group（group G）and the conventional fluid therapy group（group C）.In group G,SVV values calculated by the Flotrac/Vigileo monitor were used to guide fluid supplementation,and SVV was maintained≤13%.While in group C,volume therapy was performed according to the classical fluid management strategies.Intraoperative CVP were maintained at 8 to12cm H2O.Heart rate（HR）,mean arterial pressure（MAP）and local cerebral oxygen saturation（r SO2）of the two groups were recorded before anesthesia induction（T₀）,10 min after anesthesia（T₁）,before carotid artery blocking immediately（T₂）,20 min after carotid artery blocking（T₃）,carotid artery opening immediately（T₄）,5 min after carotid artery opening（T₅）and 20 min after carotid artery opening（T₆）.Radial artery blood and jugular bulb blood were collected for blood gas analysis at T₁,T₂,T₃,T₆points.Jugular bulb oxygen saturation（Sjv O2）and lactic acid value（jv Lac）were recorded at the same time,the arterial to jugular bulb oxygen content difference（Da-jv O₂）and cerebral extraction rate of oxygen（CERO₂）were calculated,and the concentrations of S100βprotein and NSE were detected.The anesthesia duration,volume of fluid infusion,urine volume and hosipitalization days were recorded.We assessed MMSE scores on the 1st day before operation,1st day after operation and 3rd day after operation to evaluate the prognosis of patients.Results:1.A total of 48 patients were included in this study,8 of whom were excluded,and 40 patients（20 each in group G and C）were eventually included in the analysis.Compared with group C,the amount of total transfusion,crystalloid and colloid in group G were significantly decreased（P<0.05）.2.Compared with group C,the MAP of T₁ in group G were significantly higher（P<0.05）.3.Compared with group C,the r SO₂ were significantly higher in group G at T₃,T₄,T₅,T₆ points（P<0.05）.4.Compared with group C,the Sjv O₂were significantly higher in group G at T₂,T₃and T₆points（P<0.05）,the Da-jv O₂and CERO₂were significantly lower at T₂,T₃and T₆points（P<0.05）.5.Compared with group C,the concentration of S100βprotein in group G were significantly decreased at T₆（P<0.05）,and the NSE concentration in group G were significantly lower at T₃ and T₆（P<0.05）.6.Compared with group C,the MMSE scores of group G were significantly increased in d₁ and d₃（P<0.05）.Conclusions:Goal-directed fluid therapy in patients with carotid endarterectomy can improve the cerebral oxygen supply-demand balance,optimize fluid therapy and increase the early prognosis of patients.