The Study Of Remifentanil In Children Anesthesia

【Objective】The aim of this study was to evaluate the safety and efficacy of anaesthesia using propofol and remifentanil in children undergoing gastrointestinal endoscopy;and to determine the ED₅₀ of remifentanil to produce successful intubating conditions following inhalation induction of anaesthesia using 5%sevoflurane without the use of neuromuscular blocking drugs.【Methods】1.Comparing remifentanii with ketamine in children undergoing gastrointestinal endoscopy80 ASAâ… -â…¡,aged 3 to 7 years children,undergoing gastrointes-tinal endoscopy were randomly assigned to receive either remifentanil-propofol(RP;n=40) or ketamine-propfol(KP;n=40).RP group received 80μg.kg^-1.min^-1 propofol+0.1μg. kg^-1.min^-1 remifentanil,and KP group received 80μg.kg^-1.min^-1 propofol+20μg.kg^-1. min^-1 ketamine after a bolus of propofol(2mg.kg^-1) was administered i.v.in each group.Additional propofol(1mg.kg^-1) was administered before procedu-ral in either group.HR,NIBP,S_pO2,RR,were recorded perioperatively for each child.In addition, recovery,discharge times and side effect were recorded.2.ED₅₀ of remifentanil for tracheal intubation during 5%sevoflurane induction without neuromuscular blockade in childrenTwenty-five ASAⅠ～Ⅱchildren aged 3-10 years,undergoing general anesthesia. Sixty seconds after inhalation induction of anaesthesia using sevoflurane 5%in 100% oxygen,a predetermined dose of remifentanil was injected over 30s.The dose of remifentanil was determined using the modified Dixon's up-and-down method(1.2 as a step size).The first patient was tested at 1.0μg.kg-1 remifentanil.Ninety seconds following the bolus administration of remifentanil,the child's trachea was intubated.【Results】1.Comparing remifentanil with ketamine in children undergoing gastrointestinal endoscopy1.1 All 80 procedures were completed with no complication in less than 1 hours.1.2 circulatory system change(1) blood pressure changeâ‘ comparison in the group:Compared with the pre-anesthesia,in RP group,children's mean arterial pressure(MAP) did not change significantly between before and 10 min after gastroscopy placement,p＞0.05;in KP group,there is no different change of children's MAP between the pre-anesthesia and pre-gastroscopy placement,but after 10 min gastroscopy placement,MAP increased significantly(p＜0.05).â‘¡comparison between two groups:There was no significant difference of MAP pre-anesthesia and before gastroscopy placement in the two groups(P＞0.05);MAP increased after 10 min of gastroscopy placement in KP group(p＜0.05).(2) heart rate changeâ‘ comparison in the group:there was no significant change of the heart rate before and after gastroscopy placement compared with the pre-anesthesia in the RP group(p＞0.05).There was no significant change of the heart rate before gastroscopy placement compared with pre-anesthesia in KP group,but the heart rate increased significantly after 10min of gastroscopy placement compared with pre-anesthesia,(p＜0.05).â‘¡compared between two groups:there was no significant change of the heart rate in the pre-anesthesia between RP and KP group,(p＞0.05);HR in RP group increased significantly before and after 10 min of gastroscopy placementer compared with these in KP group,(p＜0.05).1.3 The RP combination resulted in shorter wakentime and faster recovery.(p ＜0.05).But the group RP experienced higher ratio in respiratory depression compared with group KP.2.ED₅₀ of remifentanil for tracheal intubation during 5%sevoflurane induction without neuromuscular blockade in childrenThe ED₅₀ of remifentanil required for successful tracheal intubation was 0.68μg.kg-1 during inhalation induction using 5%sevoflurane in the absence of neuromuscular blocking drugs.【Conclusions】1.Both RP and KP combinations provided effective,safe sedation in paediatric patients undergoing gastrointestinal endoscopy.But the group RP experienced shorter wakentime,faster recovery and higher ratio in respiratory depression too.2.Remifentanil can be used safely and effectively in inhalation induction of anaesthesia using 5%sevoflurane without the use of neuromuscular blocking drugs. And the ED₅₀ ofremifentanil was 0.68μg.kg^-1(95%CI,0.654～0.706),during inhalation induction using 5%sevoflurane in the absence of neuromuscular blocking drugs.