The Influence Of Remifentanil On The ED50 Of Propofol For Successful Insertion Of The Laryngeal Mask Airway In Pediatric Patients

ObjectivesTo observe the influence on the LMA insertion by remifentanyl pretreatment in children.Methods50 patients(3-7years old)undergoing lower abdominal or perinea surgery were randomly allocated to propofol with saline group (PS) and propofol with 1ug/kg remifentanil group (PR). The patients were premedicated with intramuscular atropine 0.01mg/kg 30 min before anesthesia. Thirty s after the remifentanyl or saline injection, a predetermined dose of 1% propofol was given. Insertion of the LMA was attempted 90 s after the completion of the propofol injection. The dose of propofol given to a particular patient was determined by the response of the preceding patient in that group to a higher or lower dose, using the up-and-down method. The first patient in each group received 2mg/kg of propofol, ED50 of propofol requirements for the two groups were obtained using the probit model.ResultsThere was no statistical difference in age, sex ratio, weight, surgery time and duration of anesthesia(P>0.05). ED50 of propofol requirements were significantly less in the remifentanyl group (1.91mg/kg) than those in the saline group (3.18mg/kg)(P<0.05).ConclusionsOur results indiicate that preadministration of remifentanyl lug/kg decreases the propofol requirement for the LMA insertion.