Impact Of Epidural Low-dose Naloxone On Patients Receiving Intravenous Sufentanil For Postoperative Analgesia

Objective:Through ovserving the effect of low-dose naloxone on the analgesic potency of sufentanil in patient-controlled intravenous analgesia(PCIA) and on post-operative nausea and vomiting(PONV),then investigate its possible mechanism.Methods:1.General materials:100 Female patients that received hysterectomy in general anesthesia combined epidural block anesthesia,ASAâ… -â…¡,age 30-50,BMI 17-25kg/m²,choose L_2-3 intervertebral space to puncture,2%lidocaine injected in epidural space to ensure interface,then maintain the blocking interface in T8-6 level during the operation with 1%lidocaine+0.2%decicaine.Take general anesthesia with sufentanil+succinylcholin+propofol,maintain with vecuronium+ sevoflurane.2.Group:Four groups divided by random charter method(25 case, each group):C group(control):sufentanil 0.4ug/kg/h for intravenous analgesia;N1,N2,N3 group receive the same analgesic medicine with C group,but the addition of epidural naloxone 5ug/ml,10ug/ml,20ug/ml.3. Observation:After operation 6,12,24h,record the vital signs,effect of analgesia(VAS score),PONV,respiration status etc by double blind method.4.Statistical analysis:Choose SPSS 11.5 software to analyse, mean standard deviation express quantitative date,and use two independent sample t-test or one way analysis of variation(ANOVA),then use LSD or SNK test further;Chi-squared test were used in qualitative data,the degree and the incidence of PONV were tested by Kruskal-Wallis test,P＜0.05 wereconsidered significant.Results:1.Analgesic potency:At rest,compared with C group,the VAS of N1 group is obviously low than C group in 12h after operation(P＜0.05),the VAS of N2 and N3 group is no better than C group(P＞0.05).Compared with N1 group,the VAS of N2 and N3 group is obviously high in 12h after operation(P＜0.05 and P＜0.01).At movement,compared with C group,the VAS of N1 group is obviously low in 12h after operation(P＜0.05),N3 group is obviously high than C group in 6h after operation(P＜0.05).Compared with N1 group,in 12h after operation,the VAS of N2 and N3 group is obviously high(P＜0.05 and P＜0.01).2.PONY:Compared with C group,the symptoms of nausea,vomiting is obviously decreased in group N1,N2,N3(P＜0.05,P＜0.05,P＜0.05),the number of patients who need treatment for PONV are decreased also((P＜0.05,P＜0.05,P＜0.05).Conclusions:Epidural low-dose naloxone can decrease nausea and vomiting caused by postoperative sufentanil analgesia;5ug/ml of naloxone can inhance the analgesic potency of sufentanil also;but 10ug/ml or 20ug/ml of naloxone can't do the same.