超声引导下臂丛神经阻滞技术,浙医二院麻醉科 周金锋,一、臂丛相关解剖基础,由第5-8颈神经前支和第1胸神经前 支大部分构成，经椎动脉后方、斜 角肌间隙向外侧穿出，组成三条干： C5、C6前支组成上干 C7前支单独成为中干 C8前支和T1前支大部分合成下干在锁骨后第1肋骨中外缘分为前后两股腋窝水平分成三束： 上干和中干的前股合成外侧束-肌皮和正中神经 下干的前股成为内侧束-尺神经 三条干的后股组成后束-桡神经,一、臂丛相关解剖基础,一、臂丛相关解剖基础,一、臂丛相关解剖基础,一、臂丛相关解剖基础,二、超声下图像,C5 C6 C7VA,二、超声下图像,C5 C6 C7 C8 VA,二、超声下图像,M A UR,三、实战攻略,临床关注点 起效时间 阻滞程度 药物剂量 成功率 操作难度 并发症,超声技术可以解决以上问题的关键神经的定位及辨识度设备因素 神经变异（50%） 操作技术,三、实战攻略定位,三、实战攻略定位,三、实战攻略定位,三、实战攻略定位,三、实战攻略,三、实战攻略,单点阻滞用于术后镇痛An ultrasound (US)-guided block at the C7 root； Initial volume of ropivacaine 0.75% was 6 mL； Block success or failure determined a 1-mL decrease or increase for the subsequent patient； The minimum effective volume of local anesthetic in 50% and 95% of the patients was 2.9 mL (95% confidence interval, 2.4-3.5 mL) and 3.6 mL (95% confidence interval, 3.3-6.2 mL)；Minimum effective volume of local anesthetic for shoulder analgesia by ultrasound-guided block at root C7 with assessment of pulmonary function.Reg Anesth Pain Med. 2010 Nov-Dec;35(6):529-34.,三、实战攻略,分干阻滞最低剂量 Successful surgical anesthesia for arthroscopic shoulder surgery can be achieved with 5 mL of 0.75% ropivacaine, or approximately 1.7 mL per each of the 3 trunks of the brachial plexus (superior, middle, and inferior). For the group as a whole, the median (range) sensory block onset time was 5 (5-20) minutes, the median (range) motor block for the biceps was 7.5 (5-15) minutes. The median (range) block duration was 9.9 (5-19) hours, and the mean (SD) block performance time was 8.0 3.2 minutes. Mean duration of analgesia was 9.9 3.7 hours. Duration of analgesia was not associated with volume of LA (r = 0.05, P = 0.83)The minimum effective anesthetic volume of 0.75% ropivacaine in ultrasound-guided interscalene brachial plexus block. Anesth Analg. 2011 Oct;113(4):951-5.,三、实战攻略,单点阻滞最低剂量研究 The proportion of patients with successful blockade increased sharply from approximately 57% at 6 ml to 100% by 7 ml, indicating that a small increase in volume of ropivacaine 0.75% markedly affects the success rate. The median (min-max) sensory block onset time was 5 (5-20) min, the median (min-max) motor blocks for the biceps and the deltoid muscles were 7.5 (5-15) min and 10 (5-15) min, respectively. The median (min-max) block duration was 8.9 (3-15) h.Effective volume of ropivacaine 0.75% through a catheter required for interscalene brachial plexus blockade.Anesthesiology. 2013 Apr; 118 (4):863-7.,三、实战攻略,最低剂量及作用时间研究 Lidocaine 1.5% with epinephrine 1:200 000 The mean (95% CI) volume to surround each nerve was: radial 3.42 (2.84-3.99) ml, median 2.75 (2.31-3.19) ml, ulnar 2.58 (2.14-3.03) ml, and musculocutaneous 2.30 (1.96-2.64) ml. The mean (95% CI) onset time for complete sensory block was: radial 22.5 (13.5-31.5) min, median 26.8 (18.5-35.0) min, ulnar 26.6 (17.8-35.4) min, and musculocutaneous 15.8 (7.45-24.2) min. The mean (95% CI) last recorded time with complete block was: radial 137.1 (105.6-168.7) min, median 144.7 (123.4-166.0) min, ulnar 183.2 (158.1-208.2) min, and musculocutaneous 158.3 (131.8-184.9) min. Minimum volume of local anaesthetic required to surround each of the constituent nerves of the axillary brachial plexus, using ultrasound guidance: a pilot study.Br J Anaesth. 2010 May; 104 (5) :633-6.,三、实战攻略,锁骨下阻滞High-resolution ultrasonography has revealed anatomical variations of C5, C6 and C7 nerve roots in almost half of the patients examined, without negative block effectiveness. Infraclavicular catheters provide superior analgesia when compared with supraclavicular catheters. Multiple-site injections of local offer no advantage over a single-site injection during an infraclavicular block.Ultrasound-guided peripheral nerve blockade of the upper extremity. Curr Opin Anaesthesiol. 2012 Apr;25(2):253-9.,三、实战攻略,锁骨下阻滞 The supraclavicular approach of the brachial plexus has a high success rate including blockade of the ulnar and musculocutaneous nerve, which can be missed respectively with the interscalene and axillary approach.Supraclavicular brachial plexus blocks: review and current practice. Acta Anaesthesiol Belg. 2012;63(1):15-21.,三、实战攻略,地塞米松The addition of dexamethasone may prolong analgesia after single-shot interscalene and supraclavicular blocks.Ultrasound-guided peripheral nerve blockade of the upper extremity. Curr Opin Anaesthesiol. 2012 Apr;25(2):253-9.,三、实战攻略,地塞米松 The median time of a sensory block was equivalent for perineural and i.v. dexamethasone: 1405 min (IQR 1015-1710) and 1275 min (IQR 1095-2035) for RD and RDiv. I.V. dexamethasone is equivalent to perineural dexamethasone in prolonging the analgesic duration of a single-shot ISB with ropivacaine. There was a significant difference between the ropivacaine group: 757 min (IQR 635-910) and the dexamethasone groups (P0.0001). As dexamethasone is not licensed for perineural use, clinicians should consider i.v. administration of dexamethasone to achieve an increased duration of Interscalene brachial plexus block（ISB）.I.V. and perineural dexamethasone are equivalent in increasing the analgesic duration of a single-shot interscalene block with ropivacaine for shoulder surgery: a prospective, randomized, placebo-controlled study. Br J Anaesth. 2013 Sep;111(3):445-52.,