Abstract: Objective: To observe the effects of pre-injection of parecoxib sodium on emergence agitation in children with sevoflurane anesthesia.Methods: One hundred and twenty children scheduled by cheft palate repair treated with sevoflurance anesthesia were randomly divided into the low dose parecoxib sodium(L group),medium dose parecoxib sodium(M group),high dose parecoxib sodium(H group) and control group(C group)(30 cases each group).Before induction of anaesthesia,the L,M,H and C group were intravenously injected using 0.5mg/kg parecoxib,0.75mg/kg parecoxib,1mg/kg parecoxib and 0.9% normal saline,respectively.All cases were induced with oxygen mask(6 L/min) combined with 8% sevoflurance,and then were treated with 0.05mg/kg midazolam,0.1mg/kg vecuronium and 3μg/kg fentanyl by intravenous injection.The patients were endotracheally intubated and maintained anaesthesia using 2% to 3% until the end of operation.The operation condition,emergence agitation,pain,sedation and adverse reaction after 24 h of operation were recorded.Results: The differences of the anesthesia time,operation time,extubation time and PACU stay time between four groups were not statistically significant(P>0.05).The incidences of the agitation in M group and H group were lower than that in C group(P<0.05).The PAED scores in L,M and H groups after anesthesia were significantly lower than that in C group(P<0.01),whose in M and H groups were lower than that in L group(P<0.05),and the differences of the incidences of the agitation and PAED scores between M and H group were not statistically significant(P>0.05).Compared with the FLACC and Ramsay scores in C group,whose in L,M and H group decreased and increased significantly,respectively(P<0.05 to P<0.01).Compared with the L group,the FLACC scores in M and H groups at T₀ and T₁ decreased(P<0.05 to P<0.01),and the Ramsay scores in M and H groups at T₁ and H group at T₂ increased(P<0.05 to P<0.01).The differences of between the FLACC scores at each point and Ramsay scores at T₀ and T₁ in H group,and M group were not statistically significant(P>0.05),but the Ramsay score in H group at T₂ was significantly higher than that in M group(P<0.01).The differences of headache,dizziness and respiratory depression between four groups were not statistically significant(P>0.05).Conclusions: The pre-injection of parecoxib sodium can effectively prevent the occurrence of emergence agitation and obvious adverse reaction in children with sevoflurane anesthesia.The pre-injection of 0.75mg/kg parecoxib sodium in preventing the emergence agitation in children.