Department of Anesthesia and Perioperative Medicine, Western University, London, Ontario, Canada.
Department of Anesthesia and Perioperative Medicine, Western University, London, Ontario, Canada.
J Clin Anesth. 2017 Nov;42:69-76. doi: 10.1016/j.jclinane.2017.08.018. Epub 2017 Aug 19.
The role of the programmed intermittent bolus (PIB) technique for infusion of local anesthetics in continuous peripheral nerve blockade (CPNB) remains to be elucidated. Randomized controlled trials (RCTs) on PIB versus continuous infusion for CPNB have demonstrated conflicting results and no systematic review or meta-analysis currently exists. We aimed to delineate via systematic review with meta-analysis if there is any analgesic benefit to performing PIB versus continuous infusion for CPNB.
We conducted a systematic review and random-effects meta-analysis of RCTs.
We searched Medline, Embase, and the Cochrane Library without language restriction from inception to 2-May-2017.
Included RCTs had to compare PIB to continuous infusion in adult surgical patients receiving any upper or lower limb CPNB for postoperative analgesia. VAS pain scores were the primary outcome. The Cochrane Risk of Bias Tool with GRADE methodology was utilized to assess evidence quality.
Nine RCTs (448 patients) met the inclusion criteria. Two studies performed upper limb blocks and the rest lower limb blocks. Five RCTs activated the CPNB with long-acting local anesthetic and only five used multi-modal analgesia. PIB modestly reduced VAS pain scores at 6h (-14.2mm; 95%CI -23.5mm to -5.0mm; I=82.5%; p=0.003) and 12h (-9.9mm; 95%CI -14.4mm to -5.4mm; I=12.4%; p<0.001), but not at later time points. There were no other meaningful differences in the rest of the outcomes, apart from more residual motor block with PIB (OR 4.27; 95% CI 1.08-16.9; p=0.04; NNTH=8). GRADE scoring ranged from low to very low.
The existing evidence demonstrates that PIB does not meaningfully reduce VAS pain scores in CPNB. This systematic review provides important information about the limitations of existing studies. Future studies should reflect contemporary practice and focus on more painful operations.
程控间歇性推注（PIB）技术在连续外周神经阻滞（CPNB）中输注局部麻醉剂的作用仍有待阐明。PIB 与 CPNB 连续输注的随机对照试验（RCT）结果相互矛盾，目前尚无系统评价或荟萃分析。我们旨在通过系统评价和荟萃分析来确定 PIB 与 CPNB 连续输注相比是否具有任何镇痛优势。
我们对 RCT 进行了系统评价和随机效应荟萃分析。
我们在 Medline、Embase 和 Cochrane Library 进行了无语言限制的检索，检索时间截至 2017 年 5 月 2 日。
纳入的 RCT 必须比较 PIB 与成人手术患者接受任何上肢或下肢 CPNB 术后镇痛的连续输注。视觉模拟评分（VAS）疼痛评分是主要结局。采用 Cochrane 偏倚风险工具和 GRADE 方法学评估证据质量。
9 项 RCT（448 例患者）符合纳入标准。两项研究进行了上肢阻滞，其余研究进行了下肢阻滞。五项 RCT 使用长效局部麻醉剂激活 CPNB，只有五项研究使用多模式镇痛。PIB 在 6 小时（-14.2mm；95%CI-23.5mm 至-5.0mm；I=82.5%；p=0.003）和 12 小时（-9.9mm；95%CI-14.4mm 至-5.4mm；I=12.4%；p<0.001）时，VAS 疼痛评分略有降低，但在其他时间点没有差异。除了 PIB 残留运动阻滞更多（OR 4.27；95%CI 1.08-16.9；p=0.04；NNTH=8）外，其他结局无其他有意义差异。GRADE 评分范围为低至极低。
现有证据表明，PIB 不能显著降低 CPNB 中的 VAS 疼痛评分。本系统评价提供了关于现有研究局限性的重要信息。未来的研究应反映当代实践，并侧重于更疼痛的手术。
