血管手术的区域麻醉

背景建立初级动静脉瘘（arteriovenous fistula，AVF）的失败率约为25％，其原因在于血栓形成或管径与血流不足。患者的特征和手术技术影响瘘管的成熟，但是增加血管直径和提高瘘管血流速度是AVFs成功的两个最重要的预后因素。应用于血管手术的麻醉技术（监测下的麻醉、区域阻滞和全身麻醉）可能影响这些特征和瘘管的建立。方法通过关键字在PubMed／MEDLINE数据库进行文献检索。有7篇文章涉及麻醉对AVF形成的影响，包括交感阻滞、静脉扩张、血流、不良后果或者开放率，本综述的数据来源于这7篇文章。结果区域麻醉处理后血管显著扩张，见于头静脉和贵要静脉，这些血管扩张的特性可能有助于AVF部位的选择。在术中和术后，区域麻醉的应用相比于其他的麻醉技术，可明显增加瘘管血流。交感阻滞有利于血管扩张和减少血管痉挛。应用区域阻滞来建立AVF可缩短瘘管成熟时间，降低失败率，提高开放率。结论区域阻滞可有效的扩张血管，增加瘘管血流，交感截断样效应和缩短成熟时间，从而提高血管手术的成功率。然而仍需要大规模的前瞻性的临床试验来比较不同麻醉技术从而证实本文的观点。

BACKGROUND： Approximately 25% of initial arteriovenous fistula （AVF） placements will fail as a result of thrombosis or failure to develop adequate vessel size and blood flow. Fistula maturation is impacted by patient characteristics and surgical technique, but both increased vein diameter and high fistula blood flow rates are the most important predictors of successRtl AVFs. Anesthetic techniques used in vascular access surgery （monitored anesthesia care, regional blocks, and general anesthesia） may affect these characteristics and fistula failure. METHODS： We performed a Literature search using key words in the PubMed/MEDLINE database. Seven articles that related to the effects of anesthesia on AVF construction, including sympathetic block, vein dilation, blood flow, adverse outcomes, or patency rates, comprised the sources for this review. RESULTS： Significant vasodilation after regional block administration is seen in both the cephalic and basilic veins. These vasodilatory properties may assist with AVF site selection. In the intraoperadve and postoperative periods, use of a regional block, compared with other anesthetic techniques, resulted in significantly increased fistula blood flow. The greater sympathetic block contributed to vessel dilation and reduced vasospasm. Use of regional techniques in AVF construction yielded shorter maturation times, lower failure rates, and higher patency rates. CONCLUSIONS： Use of regional blocks may improve the success of vasoular access procedures by producing significant vasodilatation, greater fistula blood flow, sympathectomy-like effects, and decreased maturation time. However, a largescale, prospective, clinical trial comparing the different anesthetic techniques is still needed to verify these findings.