Comparision of Continuous Epidural and Intravenous Sufentanil Infusion

To compare the potency, the median effective concentration(EC50)and side effects of epidural and intravenously administered sufentanil for postoperative pain relief,using a double-blind,prospective design, 60 ASAⅠorⅡ patient aged 30~50 yr with body weight index ﹤30kg/m+2 scheduled for lower abdominal operations during epidural anesthesia were randomized into one of two groups:group E (epidural) and group I (intravenous).The results show that the EC50 of sufentanil in Group E was 0.87μg/ml (95% confidence interval was between 0.79μg/ml and 0.96μg/ml);the EC50 of sufentanil in Group I was 0.63μg/ml (95% confidence interval was between 0.55 μg/ml and 0.70μg/ml);The severity of nausea,pruritus were similar for both groups.The scores of Rammsay in group I were significantly higher than in those who received epidural sufentanil.Therefore the potency of continuous intravenous sufentanil infusion is significantly greater than epidural route.This suggest that when sufentanil is administered epidurally the primary mechanism is via systemic absorption to produce supraspinal analgesia.