ABSTRACT
Objective To investigate the effects of low-dose ketamine combined with fentanyl or sulfentanyl in postoperative patient-controlled intravenous analgesia.Methods Two hundred cases with ASA Ⅰ~Ⅱ undergoing elective orthopedic operations were randomly allocated into four groups(50 cases for each group): 0.4?g/(kg?h) fentanyl(group F);0.2?g/(kg?h) fentanyl+120?g/(kg?h) ketamine(group FK);0.04?g/(kg?h) sulfentanyl(group S);and 0.02?g/(kg?h) sulfentanyl+120 ?g/(kg?h) ketamine(group SK).8mg of ondansetron was added to each recipe,and then diluted into 100ml with normal saline.The loading doses of all the patient-controlled-analgesics were 2ml administered 30min before the end of the operation.The background infusion doses were 2ml/h,while the pressing doses were 2ml,with intervals of 30min.Heart rate(HR),blood pressure(BP),respiration rate(RR),pulse O2 saturation and visual analogue scales(VAS),sedation score(SS) with adverse effects and the total times of pressing PCA pump button were observed and recorded in all patients respectively for 48h after operations.Results No statistically significant differences were found in HR,BP and RR among the four groups.VAS and the total pressing times in group F were higher than that in the other groups significantly(P