St. Luke's-Roosevelt Hospital Center, 1111 Amsterdam Avenue, New York, NY 10025, USA.
Anesth Analg. 2011 Feb;112(2):471-6. doi: 10.1213/ANE.0b013e3182042f7f. Epub 2010 Dec 14.
Short- and long-acting local anesthetics are commonly mixed to achieve nerve blocks with short onset and long duration. However, there is a paucity of data on advantages of such mixtures. We hypothesized that a mixture of mepivacaine and bupivacaine results in a faster onset than does bupivacaine and in a longer duration of blockade than does mepivacaine.
Sixty-four patients undergoing arthroscopic shoulder surgery (ages 18 to 65 years; ASA physical status I-II) with ultrasound-guided interscalene brachial plexus block as the sole anesthetic were studied. The subjects were randomized to receive 1 of 3 study solutions: 30 mL of mepivacaine 1.5%, 30 mL of bupivacaine 0.5%, or a mixture of 15 mL each of bupivacaine 0.5% and mepivacaine 1.5%. The block onset time and duration of motor and sensory block were assessed.
Onset of sensory block in the axillary nerve distribution (superior trunk) was similar among the 3 groups (8.7 ± 4.3 minutes for mepivacaine, 10.0 ± 5.1 minutes for bupivacaine, and 11.3 ± 5.3 minutes for the combination group; P = 0.21 between all groups). The duration of motor block for the combination group (11.5 ± 4.7 hours) was between that of the bupivacaine (16.4 ± 9.4 hours) and mepivacaine (6.0 ± 4.2 hours) groups (P = 0.03 between bupivacaine and combination groups; P = 0.01 between mepivacaine and combination groups). Duration of analgesia was the shortest with mepivacaine (4.9 ± 2.4 hours), longest with bupivacaine (14.0 ± 6.2 hours), and intermediate with the combination group (10.3 ± 4.9 hours) (P < 0.001 for mepivacaine vs. combination group; P = 0.01 for bupivacaine vs. combination group).
For ultrasound-guided interscalene block, a combination of mepivacaine 1.5% and bupivacaine 0.5% results in a block onset similar to either local anesthetic alone. The mean duration of blockade with a mepivacaine-bupivacaine mixture was significantly longer than block with mepivacaine 1.5% alone but significantly shorter than the block with bupivacaine 0.5% alone.
短时效和长时效局部麻醉剂常混合使用，以实现起效迅速、时效持久的神经阻滞。然而，目前关于此类混合制剂优势的数据有限。我们假设甲哌卡因和布比卡因的混合物起效快于布比卡因，时效长于甲哌卡因。
64 例行超声引导下肩胛上神经丛阻滞的择期肩关节镜手术患者（年龄 18-65 岁；ASA 身体状况 I-II 级）参与本研究。患者随机接受 3 种研究药物之一：30ml 甲哌卡因 1.5%、30ml 布比卡因 0.5%或 15ml 布比卡因 0.5%和 15ml 甲哌卡因 1.5%的混合物。评估阻滞起效时间和运动及感觉阻滞的时效。
腋神经（上干）分布的感觉阻滞起效时间在三组间相似（甲哌卡因组 8.7±4.3 分钟，布比卡因组 10.0±5.1 分钟，混合组 11.3±5.3 分钟；组间比较 P=0.21）。混合组的运动阻滞时效（11.5±4.7 小时）在布比卡因组（16.4±9.4 小时）和甲哌卡因组（6.0±4.2 小时）之间（布比卡因组与混合组间比较 P=0.03，甲哌卡因组与混合组间比较 P=0.01）。镇痛时效最短的是甲哌卡因（4.9±2.4 小时），最长的是布比卡因（14.0±6.2 小时），混合组处于中间（10.3±4.9 小时）（甲哌卡因组与混合组间比较 P<0.001，布比卡因组与混合组间比较 P=0.01）。
在超声引导下肩胛上神经丛阻滞中，甲哌卡因 1.5%和布比卡因 0.5%的混合物起效与单独使用任一局部麻醉药相似。甲哌卡因-布比卡因混合物的阻滞时效显著长于单独使用甲哌卡因，但短于单独使用布比卡因。
