Schier Robert, Guerra Diana, Aguilar Jorge, Pratt Gregory F, Hernandez Mike, Boddu Krishna, Riedel Bernhard
Department of Anesthesiology and Postoperative Intensive Care Medicine, University of Cologne, Cologne, Germany.
Anesth Analg. 2009 Dec;109(6):2012-21. doi: 10.1213/ANE.0b013e3181bc113a.
The best method for identifying the epidural space for neuraxial blocks is controversial. We conducted this meta-analysis to test the hypothesis that loss of resistance with liquid reduces complications with epidural placement.
The MEDLINE, EMBASE, and Cochrane databases were searched for prospective, randomized studies comparing air versus liquid as the medium for loss of resistance during epidural space identification in adults. Data were abstracted from 5 studies (4 obstetric and 1 nonobstetric) (n = 4422 patients) that met inclusion criteria and analyzed for the following 6 outcomes: difficult catheter insertion, paresthesia, intravascular catheter insertion, accidental dural puncture, postdural puncture headache, and partial block.
The overall risk differences for adverse outcome between the different mediums were not statistically different for the obstetric population. A small, but statistically significant, risk difference for postdural puncture headache was observed when fluid was used during epidural placement for chronic pain management.
Larger studies that overcome limitations of heterogeneity across studies and a relatively infrequent occurrence of complications are required to determine the optimal medium for loss of resistance during epidural block.
确定神经轴阻滞硬膜外间隙的最佳方法存在争议。我们进行了这项荟萃分析，以检验使用液体阻力消失法可减少硬膜外穿刺并发症这一假设。
检索MEDLINE、EMBASE和Cochrane数据库，查找比较空气与液体作为成人硬膜外间隙识别中阻力消失介质的前瞻性随机研究。从5项符合纳入标准的研究（4项产科研究和1项非产科研究）（n = 4422例患者）中提取数据，并对以下6项结局进行分析：导管插入困难、感觉异常、血管内导管插入、意外硬膜穿刺、硬膜穿刺后头痛和部分阻滞。
不同介质之间不良结局的总体风险差异在产科人群中无统计学差异。在硬膜外穿刺用于慢性疼痛管理时使用液体，观察到硬膜穿刺后头痛存在微小但具有统计学意义的风险差异。
需要开展更大规模的研究，克服研究异质性的局限性以及并发症相对少见的问题，以确定硬膜外阻滞时阻力消失的最佳介质。
