芬太尼对罗哌卡因低位硬膜外麻醉效果的影响

Effects of fentanyl on the anesthetic effect and dose-effect relationship of ropivacaine in lower epidural anesthesia

目的探讨芬太尼对罗哌卡因行低位酽膜外麻醉时的麻醉效果及其量效关系的影响。方法60例ASAⅠ-Ⅱ级择期腰椎间盘手术成年病人,随机分为A、B、C三组,每组20例,均于T_(12)/L_1椎间隙行硬膜外腔穿刺,向下置管3cm。硬膜外局麻药配方分别为:A组0.5%罗哌卡因、B组0.5%罗哌卡因+芬太尼2mg/L、C组0.5%罗哌卡因+芬太尼4 mg/L。观察记录麻醉效果,持续时间,运动阻滞程度及副作用等。应用Probit半数效量回归法分别计算三组ED_(50)值和ED_(95)值。结果三组配方60例病人在腰椎手术中行硬膜外麻醉有58例获得满意效果。罗哌卡因在C组ED_(50)值和ED_(95)值均明显小于A组(P<0.05)。C组麻醉持续时间较A、B组长,Bmmage评级较A、B组低(P<0.05),三组间不良反应发生例数无统计学意义(P>0.05)。结论低位硬膜外麻醉时芬太尼能明显增强罗哌卡因麻醉效果,延长麻醉作用时间,并减轻下肢运动阻滞程度,其中C组效果最佳。

Objective To investigate the effects of fentanyl on the anesthetic effect and dose-effect relationship of ropivacaine for epidural anesthesia. Methods Sixty patients with ASA physical status I-Ⅱ scheduled for partial removal of vertebral disc were randomly divided into 3 groups（ A, B, C） , 20 patients in each group. Epidural puncture was performed at T12/ L1 intervertebral space, and the catheter was inserted 3 cm into the epidural space toward caudae in all patients. The local anesthetic compounding regimen was 0. 5% ropivacaine, 0.5% ropivacaine ＋ fentanyl 2 mg/L, or 0.5% ropivacaine ＋ fentanyl 4 mg/L for group A, B, C, respectively. The level of sensory anesthesia and degree of motor block were assessed by pinprick and modified Bromage scale, respectively. The volume of local anesthetic administrated, anesthesia duration, and side effects were also recorded. The ED50 and ED95 in each group were obtained by probit analysis. Results The anesthetic effect was satisfactory in 58 of 60 patients. The ED50 （ 27.94 mg ±8.4 mg） and ED95 （56.48 mg ±9.92 mg ） of ropivacaine of group C were significantly less than those of group A （ ED50 37.56 mg ± 8.5 mg and ED95 75.94 mg±21.4 mg, P 〈 0.05）. The modified Bromage score in group C （0.45±0.5） was significantly lower than that in group A （1.85±0.7） and groupB （1.65±0.7）, P〈 0.05. The duration of anesthesia for groupA, B, Cwere225 min ± 23 min, 340 min ± 47 min, and 410 min ＋ 36 min,respectively. There was no significant difference in the incidence of side effects and complications among the 3 groups. Conclusion In epidural anesthesia, fentanyl could improve the anesthetic effects of ropivacaine, prolong the anesthetic duration and decrease ropivaeaine dosage, diminish motor blockade, especially in group C.