Estudo comparativo sobre sevoflurano e halotano na induçåo e manutençåo de anestesia pediátrica ambulatorial / A comparative study of sevoflurane versus halothane dor induction and maintance of anesthesia in pediatric outopatients

RESUMO

Background and objectives - Sevoflurane is a new anhalational agent with low blood solubility which provides rapid induction and recovery, desirable characteristics in outpatient anesthesia. The aim of this study was to compare sevoflurane and halothane regarding quality of induction, cardiovascular stability and characteristics of post-anesthetic recovery in pediatric outpatients. Methods - Forty-one physical status ASA I pediatric outpatients were allocated into two groups, as they received sevoflurane or halothane in N2O/O2 (50/50 per cent) for induction and maintenance of anesthesia. Orotracheal intubation was performed after a sigle dose of succinylcholine. Monitoring throughout the study included PET CO2, ET N2O, ET O2, ET SEVO, ET HALO, SBP, DBP and HR. Results - Exposure time to the anesthetics were similar in both groups. There were no significant differences in induction times between the groups. Times to eye opening, to obey command, to orientation, and to discharge from phase I recovery were significantly shorter in the sevoflurane group as compared to the halothane group. Time to discharge from phase II recovery was also shorter in the sevoflurane group, although not statistically significant. The incidence of adverse effects was similar in both groups. Cardiovascular stability was good with both agents. Conclusions - The smooth and rapid induction, the good cardiovascular stability and the relatively low incidence of adverse effects make sevoflurane a good anesthetic for pediatric outpatients. The results of thie study regarding postanesthetic recovery time indicate some advantage of sevoflurane over halothane. Nevertheless, the early arousal causes intense pain perception soon after discontinuation of the anesthetic, thus requiring an effective method of postoperative analgesia