RESUMEN
Objective To find out an optimal anesthesia and the d osage used in painless gastroscopy, and to evaluate its efficiency. Meth ods 200 patients undergoing painless gastroscopy were divided into 4 gr oups randomly. 2?g/kg iv of propofol was used in group Ⅰ, fentani 1?g/kg + pr opofol 2?g/kg in group Ⅱ, rimifentani 0.5?g/kg + propofol 1.5?g/kg in grou p Ⅲ, and rimifentani 0.75?g/kg + propofol 0.75?g/kg in group Ⅳ. Observed o bjects induced starting time and depth of anaesthesia, HR, R and SpO2 during o peration, side effects such as cough reflex and larynx spasm, time of regaining consciousness, postoperative side effects such as nausea and vomiting. R esult Significant differences (P≤0.01) were found between group Ⅳand the other 3 groups in starting time and depth of anaesthesia, side effects , time of regaining consciousness and suppression of respiration during operatio n. Conclusion Combined rimifentani 0.75?g/kg + propofol 0.75 ?g/kg are optimal anestheties in painless gastroscopy if side effects are preve nted.