Clinical Observation Of Goal-directed Fluid Therapy Combined With Highly Selective Alpha-2 Agonist In Severed Finger Replantation

Objective The clinical effects of goal-directed Fluid Therapy（GDFT）combined with Dexmedetomidine（DEX）on blood lactic acid,blood glucose,hemodynamics,Ramsay se-dation score and intraoperative adverse events in patients undergoing finger replantation were observed.Methods From August 2018 to December 2019,100 patients with finger replantation were selected from the Department of hand surgery of Renhe Hospital Affiliated to Three Gorges University.According to the random number method,100 patients were randomly divided into four groups,25 patients in each group:Control group（Group C）,goal-directed fluid therapy group（group G）,dexmedetomidine group（group D）,goal-directed fluid therapy combined with dexmedetomidine group（group G+D）.After entering the operating room,routine ECG monitoring was established while the venous channel was established,and non-invasive impedance hemodynamic monitor(Lifegard^TM ICG)was connected to monitor the stroke volume（SV）.All the 100 patients had brachial plexus block guided by ultrasound.According to the different experimental methods,four groups of patients were treated with different interventions.Group C:Control fluid therapy.Group G:The goal-directed fluid therapy was performed according to the SV maximization test.Group D:Dexmedetomidine was injected by intravenous pump with 0.5μg/kg load for 15min and continued to be injected at the rate of 0.5μg·kg^-1·h^-1 until 30min before the end of the operation.Group G+D:Dexmedetomidine was injected by intravenous pump with 0.5μg/kg load for 15min and continued to be injected at the rate of 0.5μg·kg^-1·h^-1 until 30min before the end of the operation.Goal-directed fluid therapy was performed by monitoring SV according to SV maximization test.The General information of the four groups were recorded,such as gender,age,weight,fasting time and operation time.Radial artery blood was collected before anesthesia（T₀）,immediately after tourniquet loosening（T₁）,15minutes after tourniquet loosening（T₂）,and 60 minutes after tourniquet loosening（T₃）to measure the blood lactate and blood glucose.The mean arterial pressure（MAP）,stroke volume（SV）,cardiac output（CO）,heart rate（HR）and Ramsay scores were collected at four time points.The occurrence of intraoperative adverse events was recorded.Results（1）There were no significant differences in gender composition,age,weight,fasting time and operation time among the four groups（P>0.05）.（2）Changes of blood lactate:Compared with T₀,the blood lactate of group G+D at each time of T₁,T₂ and T₃decreased significantly（P<0.05）.Compared with group C,G and D groups at the same time point,the blood lactate of group G+D at each time of T₁,T₂ and T₃ decreased signifi-cantly（P<0.05）.（3）Changes of blood glucose:Compared with T₀,the blood glucose of group G+D decreased at all times of T₁,T₂ and T₃（P<0.05）.Compared with C and G groups,the blood glucose of group G+D decreased at all times of T₁,T₂ and T₃ more sig-nificantly（P<0.05）.Compared with group D,the blood glucose of group G+D decreased at all times of T₁,T₂ and T₃ more significantly,but the difference was not statistically signifi-cant（P>0.05）.（4）Hemodynamic changes:In the group G+D,the intraoperative hemody-namics were stable.Compared with T₀,MAP and HR were decreased at T₁,T₂ and T₃,SV was increased,and CO was not significantly changed（P<0.05）.Compared with group G+D at the same time point,group C presented intraoperative hemodynamics instability,MAP fluctuated and SV decreased（P<0.05）.Compared with group G+D at the same time point,MAP decreased and SV increased in group G,the difference was more significant（P<0.05）,HR difference was not statistically significant（P>0.05）.Compared with group D,the hemodynamic instability,MAP,HR,SV and CO in group D were all decreased,and the difference was statistically significant（P<0.05）.（5）Ramsay sedation score changes:Ram-say sedation scores in the G+D and D groups using dexmedetomidine were significantly higher at T₁,T₂ and T₃ than those in groups C and G without dexmedetomidine（P<0.05）,and the patients had good sedation effect.There was no significant difference in Ramsay score between G+D and D groups（P>0.05）.（6）Comparison of intraoperative adverse events:Intraoperative hemodynamics was stable in the group G+D,and the incidence of hypotension and bradycardia was significantly lower than that in the C,G and D groups,while no tachycardia and vasospasm occurred during the operation（P<0.05）.Conclusion Goal-directed fluid therapy combined with dexmedetomidine can reduce the stress response of the body in the replantation of severed fingers,make the patients ob-tain good sedation and anti-anxiety effect in the perioperative period,and reduce the oc-currence of vasospasm.Reduction of microcirculatory anaerobic metabolism by dynamic optimization of circulatory perfusion alleviates tourniquet response and maintains hemo-dynamic stability.At the same time,reducing the adverse effects of dexmedetomidine on cardiovascular system and play a positive role in replantation.