Abstract: Objective To explore the effect comparison of dexamethasone combined with ropivacaine in intermuscular groove brachial plexus block.Methods  A total of 100 patients who underwent elective upper limb surgery in orthopedics department of our Hospital from March 2020 to July 2021 were enrolled.They were divided into control group according to the random number table method and groups A,B,C,and D,20 cases in each.The control group was given 0.5% ropivacaine 20ml + saline 1ml;group A was given 0.5% ropivacaine 20ml + dexamethasone 1mg,group B was given 0.5% ropivacaine 20ml + dexamethasone 2mg,and group C was given 0.5% ropivaca 20ml + dexamethasone 3mg ,group D was given 0.5% ropivacaine 20ml+ dexamethasone 4mg.Compare the effects of anesthesia,stress related indicators and adverse reactions of patients in each group.Results There were no obvious differences in the mean arterial pressure(MAP)mmHg and heart rate(HR)between the five groups of patients before anesthesia,5 min utes after anesthesia,and 6 hours after anesthesia(P>0.05).The maintenance time of sensory and motor nerve blocks in patients in groups A,B,C,and D was obvious longer than control group,and with the increase of dexamethasone dosage,the maintenance time of sensory and motor nerve blocks was gradually extended(P<0.05).The levels of norepinephrine(NE),epinephrine(E),and cortisol(Cor)in each group increased to varying degrees at 24 hours after operation,but the levels of NE,E,and Cor in the two groups were lower than those in the control group,A,B three groups,the difference is statistically significant(P<0.05).There was no significant difference in adverse reactions between the five groups during and after surgery(P>0.05).Conclusion Dexamethasone combined with ropivacaine and brachial plexusblock anesthesia can significantly prolong the nerve block time and reduce the body's stress response in patients,and it is within the safe dose range of dexamethasone  more obvious.

Key words: dexamethasone, ropivacaine, brachial plexus block, anesthetic effect