A Comparative Study of Combined Spinal-epidural Anesthesia with Ropivacaine and Bupivacaine in Cesarean Section  <?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

赵普文  

施永平   

余大松  

中国福利会国际和平妇幼保健院麻醉科,上海  200030

Puwen Zhao, Yongping Shi and Dasong Yu

The International Peace Maternity and Child Health Hospital of the China Welfare Institute, Shanghai, 200030 
                                                       　　ABSTRACT

  Objective:  To investigate dose-response relationship of ropivacaine for combined spinal-epidural anesthesia in cesarean section, and to determine the effects of ropivacaine for combined spinal-epidural anesthesia on the cardiovascular system and side-effects as compared with bupivacaine.

　　Methods:  120 primiparae (ASAⅠ-Ⅱ) scheduled for elective cesarean section were divided into four groups: group Ⅰ(n=30) received ropivacaine 9mg𔅖ml^-1 for spinal anesthesia; group Ⅱ(n=30) received ropivacaine 12mg𔅖ml^-1 for spinal anesthesia; group Ⅲ(n=30) received ropivacaine 15mg𔅖ml^-1 for spinal anesthesia; group Ⅳ(n=30) received bupivacaine 10mg𔅖ml^-1 for spinal anesthesia. During operation when spinal analgesia was inadequate, 2% lidocaine was supplemented via epidural catheter. Blood pressure, heart rate and SpO₂ were monitored. The onset time of analgesia, the height of sensory block(pin prick), Apgar score for neonates and side-effects were recorded.

　　Results:  Among the four groups ,the age, height, weight, pregnant weeks were similar before the operation(p>0.05). The MAP was declined among the four groups after anesthesia. There was no significant difference in MAP during anesthesia on same time among the four groups(p>0.05). The onset time of analgesia and the height of sensory block were similar among the four groups. The effect of anesthesia was satisfied for groupⅡ,Ⅲ,Ⅳ. There were 8 patients to require 2% lidocaine(6.75±1.62ml) via epidural catheter in group Ⅰ because the spinal analgesia was inadequate. The incidence of hypotension and bradycardia were not statistically significant among the four groups. The incidence of nausea and vomit were significantly higher in groupⅢ than that in groupⅠand Ⅱ.       

　　Conclusions:  The anesthetic efficacy of 12mg, 15mg ropivacaine were similar with combined spinal-epidural anesthesia in cesarean section  as compared with 10mg bupivacaine.The dosage of ropivacaine didn't affecte the onset time of analgesia and the height of sensory block for spinal.

  Key words: Ropivacaine; Bupivacaine; Combined Spinal-epidual Anesthesia; Cesarean Section

  Corresponding author: Puwen Zhao, MD; zhaopw2002@yahoo.com.cn 
  罗哌卡因是一种新的酰胺类局麻药，因其对中枢神经和心血管毒性低，在临床上用于腰麻的报道日益见多。药理学研究表明罗哌卡因的麻醉性能和布比卡因类似，只是效能稍弱^[1]。在临床所用硬膜外浓度下，怀孕的母羊模型中发现它对子宫动脉血流和胎儿无影响^[2]。对产妇来讲，罗哌卡因可能是一种理想的麻醉药。

  本文旨在探讨腰-硬联合麻醉下剖宫产术，罗哌卡因随剂量增加的麻醉量效关系、对循环的影响和不良反应及其与老局麻药布比卡因在这几方面的比较。

　　　　　　　　　　　　　　资料与方法
    产妇分组: 120例行剖宫产术的初产妇，ASAⅠ-Ⅱ级，随机等分为四组，Ⅰ组(n=30)腰麻用药为罗哌卡因9mg•2ml^-1;Ⅱ组(n=30)腰麻用药为罗哌卡因12mg•2ml^-1;Ⅲ组(n=30)腰麻用药为罗哌卡因15mg•2ml^-1;Ⅳ组 (n=30) 腰麻用药为布比卡因10mg•2ml^-1;四组局麻药均用0.9%的生理盐水稀释至2ml，四组产妇均无严重内科和产科并发症。
    方法: 麻醉前开放静脉，输入平衡液300ml-500ml。用一点法腰麻-硬膜外联合麻醉，L_3-4穿刺，腰麻注药时间20s-30s，硬膜外腔向头端置管3cm，术中持续鼻导管吸氧，麻醉效果不足时硬膜外腔追加2%利多卡因，术毕经硬膜外导管行病人自控镇痛(PCA)。当收缩压低于 90mmHg(1kpa=7.5mmHg)时，麻黄碱10mg静注。
    观察并记录麻醉前，麻醉后3、6、10、15分钟时血压、心率、氧饱和度；采用体表针刺法，测定阻滞平面达T₈时所需时间(起效时间)，及术前、术后麻醉阻滞最高平面；记录新生儿娩出后1min，5minApgar平分，硬膜外腔用药量及麻醉后不良反应。
    统计学处理  所有数据均用SPSS10.0统计软件包进行处理。数据用均数±标准差表示。组间用独立样本t检验，组内用配对t检验，比率用卡方检验，P<0.05为有显著性差异。
　                       　　结   果
　　一般情况  四组产妇在年龄、身高、体重和孕周等方面均无差异(p>0.05)。术中ECG， SpO₂未见异常，见表1。

　　循环系统  四组产妇注药后各观察时间段MAP均有下降，与注药前MAP比较有显著性差异(p<0.01)，罗哌卡因组与布比卡因组同一时间段MAP下降幅度无显著性差异(p>0.05)，见表2。

　　痛觉阻滞  四组麻醉起效时间及手术前后最高感觉阻滞平面相似(p>0.05)，剖宫产术历时30分钟-50分钟，术后测最高感觉阻滞平面均较术前高1-2脊髓阶段，见表3。术中Ⅱ组、Ⅲ组、Ⅳ组腰麻麻醉效能均能达到手术满意要求，Ⅰ组有8例麻醉效果不满意，硬膜外腔追加2%利多卡因(6.75±1.62ml)。<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /> 
　　不良反应  四组产妇低血压、心动过缓、恶心呕吐、颤抖的发生率，见表4。四组产妇均无术后头痛。                        
                       　讨   论
　　罗哌卡因是一种新型长效可注射用局麻药，在人类健康志愿者中，静注罗哌卡因后，产生的中枢神经系统和心血管改变较布比卡因少^[3]。在体外游离迷走神经试验中证实，对于C纤维放电的阻滞作用罗哌卡因与布比卡因具有相同的效价，但罗哌卡因对大的运动神经阻滞较弱^[4]。  

　　在麻醉质量方面 ，12mg ，15mg 罗哌卡因与10mg布比卡因在腰麻下行剖宫产术的麻醉效能相近，三组产妇的麻醉镇痛效果均满意，而9mg罗哌卡因腰麻有30%的产妇麻醉镇痛效果差，需硬膜外追加局麻药。在研究中发现，当罗哌卡因用量逐渐增加，其感觉阻滞的起效时间及阻滞扩散范围几乎不受局麻药用量的影响，与Brockway等^[5]和Wolff等^[6]报道罗哌卡因硬膜外麻醉的试验结果相似，同时他们还发现随罗哌卡因用量的增加，运动和感觉阻滞的持续时间随之延长，运动阻滞的程度也增加。

　　在循环系统影响方面，四组产妇腰麻后各观察时间段平均动脉压较麻醉前有显著下降，这可能与罗哌卡因和布比卡因对Aδ和C类纤维有更强阻滞效能，充分阻滞交感神经密切相关^[7]。经加快输液，给予适量麻黄素等对症处理后效果良好。

　　在胎儿影响方面，麻醉前后四组产妇的胎儿心率无病理性变化；新生儿Apgar 1min，5min评分为8-10分，未发现对新生儿有不良影响。　

　　在不良反应方面，心动过缓与低血压常同时发生，给予麻黄素10mg-30mg治疗后，血压回升，心率恢复。罗哌卡因组低血压和心动过缓的发生率与布比卡因组相似，但罗哌卡因组恶心呕吐的发生率随局麻药剂量增加而升高；各组均未发现术后头痛，可能是采用了笔尖型带侧孔腰麻穿刺针，此类穿刺针与传统的锐头穿刺针相比，穿刺时是钝性分开，而后者是切断硬膜纤维，故减少了腰麻后的头痛发生率^[8]。

    在腰-硬联合麻醉下行剖宫产术，12mg、15mg罗哌卡因与10mg布比卡因的麻醉效能相似;罗哌卡因腰麻下感觉阻滞起效时间和扩散范围不受局麻药用量影响。

参 考 文 献

1.     Feldman HS, Covino BG. Comparative motorblocking effects of bupivacaine and ropivacaine, a new amino amide local anesthetic, in the rat and dog. Anesth Analg, 1988, 67: 1047-1052.

2.     Santos AC, Arthur GR, Roberts DJ, et al. Effect of ropivacaine and bupivacaine on uterine blood flow in pregnant ewes. Anesth Analg, 1992, 74: 62-67.

3.     Scott DB, Lee A, Fagan D,et al. Acute toxicity of ropivacaine with that of bupivacaine. Anesth Analg, 1989, 69:563.

4.     Bader AM,Datta S, Flanagan H, et al. Comparison of bupivacaine and ropivacaine induced conduction blockade in the isolated rabbit vagus nerve. Anesth Analg, 1989, 68:724.

5.     Brockway MS, Bannister J, Mcclure JH, et al. Comparison of extradural ropivacaine and bupivacaine. Br J Anaesth, 1991, 66: 31-37.

6.     Wolff AP,  Hasselstrom L, Kerkkamp HE, et al. Extradural ropivacaine and bupivacaine in hip surgery. Br J Anaesth, 1995, 74: 458-460.

7.     Rosemberg PH, Heinonen E. Differential sensitivity of A and C fibers to long-acting  amide local anesthesia. Br J Anaesth, 1983, 55:163.

8.    王俊科等译，临床麻醉手册，第五版.辽宁科学技术出版社，193.