Abstract: 【Abstract】objective To investigate the influence of preemptive analgesia with different dosage tramadol in children with inhalational anesthetic sevoflurane on postoperative palinesthesia time, extubation time, circulation, postoperative agitation and conscious-sedation extent. Methods Ninty children(ASAⅠgrade)undertaking appendectomy were randomly divided into low dose tramadol group(group T1，n=30) , large dose tramadol group(group T2，n=30) and control group(group C，n=30).Anaesthesia was induced with sevoflurane,fentanyl and atracurium for tracheal intubation. In group T1 and group T2, 1mg/kg and 2mg/kg tramadol was administered intravenously after intubation, and in group C, normal saline was administered intravenously, anaesthesia was maintained with sevoflurane. Extubation was accomplished after the children awaked. Results There was no significant difference of palinesthesia time, extubation time and pulse oxygen saturation among three groups(P>0．05).Compared with group C,the heart rate（HR）and mean arterial pressure（MAP）of extubating and ten miniutes after extubating in group T2 decreased significantly, the incidence of postoperative agitation in group T2 also decreased significantly,and conscious-sedation extent increased significantly(P<0．01)，the HR,MAP and the incidence of postoperative agitation in group T1 decreased slightly,but there were no statistic difference（P>0．05）。Conclusion 2mg/kg tramadol could prevent postoperative agitation effectively in school children receiving inhalational sevoflurane,obtained satisfactory conscious-sedation extent and stable circulation when extubating and after extubating,and also,there were no influence on postoperative palinesthesia time and extubating time.

Key words: tramadol, Preemptive analgesia, sevoflurane, children, agitation