Section of Anesthesia and Intensive Care, Department of Critical Medical-Surgical Area, University-Hospital Careggi, Largo Brambilla, 1, 50143, Florence, Italy,
J Anesth. 2014 Jun;28(3):407-12. doi: 10.1007/s00540-013-1748-8. Epub 2013 Nov 21.
A hemodynamic event such as hypertension after interscalene block (ISB) is a complication that is often overlooked. The irregular spread of local anesthetic would cause a blockade of carotid sinus baroreceptors leading to the adverse event. The purpose of the present study is to compare ultrasound and neurostimulation technique in preventing hypertension after ISB.
Thirty patients without hypertension history who underwent arthroscopic shoulder surgery for a rotator cuff tear were enrolled. After preoperative administration of the State Trait Anxiety Inventory questionnaire, patients were allocated to receive ultrasound-guided ISB with 20 ml levobupivacaine-HCl 0.5 % (group US) and 40 ml levobupivacaine-HCl 0.5 % with neurostimulation (group NS). The need for antihypertensive drug was recorded. Block onset sensory and motor times were assessed. Systolic and diastolic blood pressures, and heart rate and pulse oximetry (SpO2), were evaluated before the block as well as 2, 5, 10, 15, 20, and 30 min after.
No differences in patient characteristics and anxiety were found in the two groups. Block onset times were similar. At 15 min after block placement, group NS showed significantly higher systolic and diastolic blood pressures compared to group US. No differences in heart rate and SpO2 were found between the two groups. Three patients of group NS required urapidil administration because of hypertension.
Ultrasound-guided ISB permits the use of a low volume of local anesthetic and seems to reduce the incidence of hypertension.
肌间沟阻滞（ISB）后出现的血流动力学事件（如高血压）是一种常被忽视的并发症。局部麻醉药的不规则扩散会导致颈动脉窦压力感受器阻滞，从而导致不良事件。本研究的目的是比较超声和神经刺激技术在预防 ISB 后高血压中的作用。
纳入 30 例无高血压病史的行肩关节镜下肩袖撕裂修复术的患者。在术前进行状态特质焦虑问卷评估后，患者被分配接受超声引导的 ISB，给予 20ml 左旋布比卡因盐酸盐 0.5%（US 组）和 40ml 左旋布比卡因盐酸盐 0.5%加神经刺激（NS 组）。记录需要使用降压药物的情况。评估感觉和运动阻滞的起始时间。在阻滞前、阻滞后 2、5、10、15、20 和 30min 时评估收缩压和舒张压、心率和脉搏血氧饱和度（SpO2）。
两组患者的一般特征和焦虑评分无差异。阻滞起始时间相似。在阻滞后 15min，NS 组的收缩压和舒张压明显高于 US 组。两组的心率和 SpO2 无差异。NS 组有 3 例患者因高血压需要使用乌拉地尔。
超声引导的 ISB 可以使用较低容量的局部麻醉药，似乎可以降低高血压的发生率。
