Department of Anesthesia, University of Iowa, Roy J. and Lucille A. Carver College of Medicine, Iowa City, IA 52242, USA.
Reg Anesth Pain Med. 2012 Jan-Feb;37(1):28-33. doi: 10.1097/AAP.0b013e318236bc30.
Practitioners mix faster-onset, intermediate-duration local anesthetics (LAs) with slower-onset, long-duration LAs to get fast peripheral nerve block (PNB) onset and long duration. We hypothesized that 1.5% mepivacaine (with epinephrine) (mepivacaine) or 1.5% mepivacaine (with epinephrine) mixed with 0.5% bupivacaine (mixed) would reduce PNB sensory onset by 20% or more versus 0.5% bupivacaine alone (bupivacaine).
Patients (n = 93) having arm surgery were randomized to 1 of the 3 LA groups. Infraclavicular PNB was administered using 1 of 3 LAs; afterward, PNB sensory (motor) onset, duration, and other outcomes were assessed. Subjects, physicians, and the biostatistician were blinded until study completion.
Median (interquartile range) PNB sensory onset (in minutes) was as follows: mepivacaine, 3 (3-6); mixed, 6 (3-6); and bupivacaine, 6 (3-12) (P = 0.0085). Mepivacaine PNB sensory onset was not faster than mixed (P = 0.57), but mixed was faster than bupivacaine (P = 0.0035). More mixed group patients achieved PNB sensory onset (0.81) versus the bupivacaine group (0.54) at 6 mins. Median (interquartile range) PNB motor onset (in minutes) was as follows: mepivacaine, 15 (12-18); mixed, 17 (12-21); and bupivacaine, 21 (12-24) (P < 0.0001). Median sensory and motor PNB duration (in minutes) was as follows: mepivacaine, 281 and 320; mixed, 439 and 556; and bupivacaine, 850 and 1109. Sensory (motor) PNB duration was shorter with mepivacaine versus mixed (P < 0.0001, P = 0.034), and mixed was shorter versus bupivacaine (P = 0.0243, P = 0.034).
Mixing 1.5% mepivacaine (with epinephrine) with 0.5% bupivacaine speeds up PNB sensory (motor) onset compared with 0.5% bupivacaine alone.
从业者将起效较快、作用时间中等的局部麻醉剂（LA）与起效较慢、作用时间较长的 LA 混合，以获得起效较快的周围神经阻滞（PNB）和较长的作用时间。我们假设 1.5%甲哌卡因（含肾上腺素）（甲哌卡因）或 1.5%甲哌卡因（含肾上腺素）与 0.5%布比卡因（混合）混合将使 PNB 感觉起始时间比单独使用 0.5%布比卡因快 20%或更多。
接受上肢手术的患者（n=93）被随机分配到 3 种 LA 组中的 1 种。使用 3 种 LA 中的 1 种进行锁骨下 PNB；之后，评估 PNB 感觉（运动）起始、持续时间和其他结果。受试者、医生和生物统计学家在研究完成前保持盲态。
中位（四分位间距）PNB 感觉起始时间（分钟）如下：甲哌卡因，3（3-6）；混合，6（3-6）；布比卡因，6（3-12）（P=0.0085）。甲哌卡因 PNB 感觉起始时间不比混合快（P=0.57），但混合比布比卡因快（P=0.0035）。混合组更多的患者在 6 分钟时达到 PNB 感觉起始时间（0.81），而布比卡因组为 0.54。中位（四分位间距）PNB 运动起始时间（分钟）如下：甲哌卡因，15（12-18）；混合，17（12-21）；布比卡因，21（12-24）（P<0.0001）。中位感觉和运动 PNB 持续时间（分钟）如下：甲哌卡因，281 和 320；混合，439 和 556；布比卡因，850 和 1109。与混合相比，甲哌卡因的感觉（运动）PNB 持续时间更短（P<0.0001，P=0.034），而混合比布比卡因更短（P=0.0243，P=0.034）。
与单独使用 0.5%布比卡因相比，将 1.5%甲哌卡因（含肾上腺素）与 0.5%布比卡因混合可加速 PNB 感觉（运动）起始。
