Clinical evaluation of fentanyl combined with small dose ketamine for post-operative analgesia

Objective To compare the static pain score and the complications of fentanyl intravenous postoperative analgesia with those of fentanyl combined with a small dose of ketamine.Methods One hundred and twenty patients after the upper abdomen operation undergoing intravenous postoperative analgesia were randomly divided into three groups(n =40 in each group).Group F:fentanyl 0.4μg/(kg ? h) plus droperidol 5 mg;Group KF1:fentanyl 0.2μg/(kg ? h) plus ketamine 40μg/(kg ? h) plus droperidol 5 mg;Group KF2:fentanyl 0.2μg/(kg·h) plus ketamine 80μg/(kg·h) plus droperidol 5 mg.The drugs in each group were diluted in normal saline 100 ml with a disposable perfusion pump of 2 ml/h. The static pain scores,incidences of nausea,vomiting,itching,urinary retention and illusion were recorded during 48 h intravenous postoperative analgesia.Results The static pain score of group KF1 and group KF2 during first 12 hours was significantly lower than that of group F(P0.05),which became similar after 12 hours.The incidences of nausea,vomiting,itching and urinary retention in group KF1 and group KF2 were also significantly lower than those of group F(P 0.01 ).These were no obvious differences in the static pain score and the adverse effects between group KF1 and group KF2.And there was no illusion occurred in three groups.Conclusion A small dose of ketamine used for intravenous postoperative analgesia could reduce fentanyl repuirement,and also reduce the incidences of nausea,vomiting,itching and urinary retention.The analgesic effects of this method is better than that of fentanyl alone.