The Appropriate Dosage Of Dexmedetomidine For Prevention Of Shivering In Percutaneous Nephrolithotomy

Objective The purpose of this topic is to evaluate the effects of dexmedetomidine on shivering response in Percutaneous nephrolithotomy,the differences of shivering prevention and treatment,hemodynamics,adverse reactions and sedation effects.To investigate the appropriate dose of dexmetoimidine for shivering response during percutaneous nephroscopy for clinical reference.Methods A total of 120 patients who was in Dongguan Hospital Affiliated to Jinan University and the First Affiliated Hospital of Jinan University in November 2016-November 2017undergoing percutaneous nephrolithotomy undergoing spinal canal anesthesia were enrolled.Patients aged 20-75 years with ASA grade I-II were randomly divided into four groups?n=30,DI,D2 and D3?.After the anesthesia were given the loading dose of 0.5?g/kg,0.75?g/kg,1.0?g/kg,infusion time of 15min,and then give 0.4?g/?kg.h?speed continuous pump until the end of surgery.The control group,N group,was given 0.9%sodium chloride injection.The patients'vital signs,chills classification,sedation score,the number of flushing fluid and adverse reactions were recorded.SPSS17.0 was used for statistical analysis of data.Measured data were expressed as mean±standard deviation.Two-factor multi-level analysis was used for repeated measurement design within the group.Then Bonferroni test was used for comparison between the two groups.Count data comparison usingc2 test,Kruskal-Wallis H rank sum test was used to compare grade data.P<0.05 for the difference was statistically significant.Results 1.There was no significant difference in age,sex,BMI and infusion between the four groups?P>0.05?;2.With the prolongation of the operation time,the increase of intraoperative flushing volume,the rectal temperature is also reduced,and the degree of chilliness is also increased.It can be considered that there is a correlation between the chilling level and the temperature;when the flush volume is greater than 20L at room temperature the incidence of chills significantly increased;3.Within group comparison,the HR of D2 and D3 groups at T3,T4 and T5 after intravenous injection of DEX was significantly lower than that at T0?P<0.05?.There was no significant difference in MAP,RR and SPO₂ at all times?P>0.05?;And there was also no significant difference in group D1 and N?P>0.05?;the Ramsay scores at T3,T4,and T5in the D3 and D2 groups were significantly different from those at T0?P<0.05?.There was no significant difference between the other groups at different time points and T0?P>0.05?;4.Between groups,D2 and D3 groups compared with N group,HR decreased significantly after pumping DEX?P<0.05?,MAP had no significant difference?P>0.05?,D1 group compared with N group,There was no significant difference in HR and MAP?P>0.05?;the Ramsay score of D3 and D2 groups after pumping Dex was higher than that of N group,and Ramsay score of D3 group was higher than that of D2 group after time T2,and the difference was statistically significant?P<0.05?;The Ramsay score was no significant difference between group D1 and group N?P>0.05?;5.The perioperative body temperature of the four groups was lower than that of T0 at time T4 in the group?P<0.05?,and both were in a low temperature state;with the extension of the operation time and anesthetic time,the flushing volume increased,the D2and D3 groups were lower than the control group N and D1 groups.The reason may be related to the decrease of chilling threshold by dexmedetomidine.There was no significant difference between the N group and the D1 group in the control group?P>0.05?;6.11 people experienced varying degrees of chills In Group N,and their chills reached Level 4.8 people experienced varying degrees of chills In Group D1 and their chilling levels also reached Level 3.The incidence of chills in group N and group D1 was 36.7%and 26.7%,respectively.The incidence of chills in group D2 and group D3 was 6.7%and3.3%,respectively,which was significantly lower than that in group D1 and group N?P<0.05?.There was no significant difference between D2 and D3 groups?P>0.05?.;7.Five patients in the D2 group and 6 patients in the D3 group had bradycardia?HR<60 beats/min.?,0.3-0.5 mg atropine was needed after injection of the drug,there was significant difference compared with group D1 and N?P<0.05?;shivering occurred in the N group and the D1 group.Patients who did not respond to intravenous administration of tramadol 50-100 mg had varying degrees of nausea and vomiting,intravenous ondansetron5 mg.There were no nausea and vomiting at all time points in each group,no bradycardia and no respiratory depression.Conclusion Dexmedetomidine can effectively prevent the occurrence of intraoperative chills in patients undergoing percutaneous nephrolithotomy,and its appropriate dose is 0.75?g/kg,which can be significantly increased after venous pumping in prone position in patients with combined spinal and epidural anesthesia Reduce the incidence and severity of chills,at the same time effectively sedating and prolonging the role of the spinal cord,relieve anxiety and improve patient comfort,no adverse drug reactions,no significant effect of ventilation in the prone position and provide a good reference for the choice of clinical drug dosage.