Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University, Stanford, California, USA.
Department of Anesthesiology, Santa Clara Valley Medical Center, San Jose, California, USA.
Reg Anesth Pain Med. 2021 Feb;46(2):124-129. doi: 10.1136/rapm-2020-101922. Epub 2020 Nov 12.
Previous case reports describe the reversal of phrenic nerve blockade from the interscalene nerve block using normal saline injectate washout. This randomized clinical trial aimed to evaluate whether using normal saline injectate to wash out local anesthetic from an interscalene nerve block catheter would restore phrenic nerve and diaphragm function, while preserving analgesia.
Institutional review board approval, clinical trial registration and consent were obtained for patients undergoing shoulder surgery with an interscalene nerve block catheter. 16 patients were randomized to receive three 10 mL aliquots of normal saline injectate (intervention group, n=8) or three sham injectates (control group, n=8) via their perineural catheters in the postanesthesia care unit (PACU). Primary outcome measures were the effects on ipsilateral hemidiaphragmatic paralysis, and secondary outcome measures included PACU opioid consumption, pain scores and change in brachial plexus sensory examination and motor function.
There was no significant difference in reversal of hemidiaphragmatic paralysis. However, there was a greater number of patients in the intervention group who ultimately displayed partial, as opposed to full, paralysis of the hemidiaphragm (p=0.03). There was no significant difference in pain scores, PACU opioid requirement, and brachial plexus motor and sensory examinations between the two groups.
All patients had persistent hemidiaphragmatic paralysis after the intervention, but fewer patients in the intervention group progressed to full paralysis, suggesting that a larger bolus dose of normal saline may be needed to completely reverse hemidiaphragmatic paralysis. Although normal saline injectate in 10mL increments given through the interscalene nerve block catheter had no clinically significant effect on reversing phrenic nerve blockade, it also did not lead to a reduction in analgesia and may be protective in preventing the progression to full hemidiaphragmatic paralysis.
NCT03677778.
先前的病例报告描述了使用生理盐水冲洗剂从肌间沟神经阻滞中逆转膈神经阻滞。这项随机临床试验旨在评估使用生理盐水冲洗剂从肌间沟神经阻滞导管中冲洗局部麻醉剂是否会恢复膈神经和膈肌功能，同时保持镇痛效果。
经机构审查委员会批准、临床试验注册和患者同意，对接受肌间沟神经阻滞导管的肩部手术患者进行研究。16 名患者随机分为两组，每组 8 名：干预组接受三次 10ml 生理盐水注射，对照组接受三次假注射。主要观察指标为同侧膈肌麻痹的影响，次要观察指标包括术后恢复室（PACU）阿片类药物消耗、疼痛评分以及臂丛神经感觉和运动功能的变化。
两组患者膈神经麻痹的逆转无显著差异。然而，干预组中最终出现膈神经部分而非完全麻痹的患者数量更多（p=0.03）。两组患者的疼痛评分、PACU 阿片类药物需求以及臂丛神经运动和感觉检查均无显著差异。
所有患者在干预后均持续出现膈肌麻痹，但干预组中进展为完全麻痹的患者较少，提示需要更大剂量的生理盐水冲洗剂才能完全逆转膈神经麻痹。尽管通过肌间沟神经阻滞导管给予 10ml 递增的生理盐水冲洗剂对逆转膈神经阻滞没有明显的临床效果，但也不会导致镇痛效果降低，并且可能有助于预防完全性膈肌麻痹的进展。
NCT03677778。
