Kapural Leonardo, Kim Billy, Eidt John, Petersen Erika A, Schwalb Jason M, Slavin Konstantin V, Mekhail Nagy
Carolinas Pain Institute and Center for Clinical Research, Winston-Salem, NC, USA.
Department of Vascular Surgery, The Surgical Clinic, Nashville, TN, USA.
Neuromodulation. 2024 Dec;27(8):1383-1392. doi: 10.1016/j.neurom.2024.08.010. Epub 2024 Sep 24.
The multicenter, randomized, double-blinded, active-sham controlled trial (high-freQUEncy nerve block for poST amputation pain [QUEST]) was conducted to show the safety and efficacy of a novel, peripherally placed high-frequency nerve block (HFNB) system in treating chronic postamputation pain (PAP) in patients with lower limb amputations. The primary outcomes from QUEST were reported previously. This study presents the long-term, single-cross-over, secondary outcomes of on-demand HFNB treatment for chronic PAP.
After the three-month randomized period, subjects in the active-sham group were crossed over to receive therapy for 12 months. Subjects self-administered HFNB therapy as needed and reported their pain (numerical rating scale [NRS]; range, 1-10) before and 30 and 120 minutes after each treatment. Pain medication use was reported throughout the study. Pain-days per week and quality of life (QOL) were assessed using the Brief Pain Inventory (BPI). Adverse events (AEs) were recorded for all subjects implanted for 12 months.
Of 180 subjects implanted in QUEST, 164 (91%) were included in the cross-over period, and 146 (82%) completed follow-up. By month 12, average NRS pain in the combined cohort was reduced by 2.3 ± 2.2 points (95% CI, 1.7-2.8; p < 0.0001) 30 minutes after treatment and 2.9 ± 2.4 points (95% CI, 2.2-3.6; p < 0.0001) 120 minutes after treatment. Mean pain-days per week were significantly reduced (-3.5 ± 2.7 days; p < 0.001), and subject daily opioid use was reduced by 6.7 ± 29.0 morphine equivalent dose from baseline to month 12 (p = 0.013). Mean BPI-interference scores (QOL) improved by 2.7 ± 2.7 points from baseline (p < 0.001). The incidence of nonserious AEs and serious AEs was 72% (130/180) and 42% (76/180), respectively; serious device-related AEs occurred in 15 of 180 subjects (8%).
Overall, HFNB delivered directly to the damaged peripheral nerve provided sustained, on-demand relief of acute PAP exacerbations, reduced opioid utilization, and improved QOL for patients with lower limb amputations with chronic PAP.
开展多中心、随机、双盲、活性安慰剂对照试验（高频神经阻滞治疗截肢后疼痛[QUEST]），以证明一种新型的、置于外周的高频神经阻滞（HFNB）系统治疗下肢截肢患者慢性截肢后疼痛（PAP）的安全性和有效性。QUEST的主要结果已在之前报道。本研究呈现了按需进行HFNB治疗慢性PAP的长期单交叉次要结果。
在为期3个月的随机分组期后，活性安慰剂组的受试者交叉接受为期12个月的治疗。受试者根据需要自行进行HFNB治疗，并在每次治疗前以及治疗后30分钟和120分钟报告其疼痛情况（数字评分量表[NRS]；范围为1 - 10）。在整个研究过程中记录疼痛药物的使用情况。使用简明疼痛量表（BPI）评估每周疼痛天数和生活质量（QOL）。记录所有植入治疗12个月的受试者的不良事件（AE）。
在QUEST研究中植入装置的180名受试者中，164名（91%）进入交叉期，146名（82%）完成随访。到第12个月时，联合队列中治疗后30分钟平均NRS疼痛评分降低了2.3±2.2分（95%CI，1.7 - 2.8；p<0.0001），治疗后120分钟降低了2.9±2.4分（95%CI，2.2 - 3.6；p<0.0001）。每周平均疼痛天数显著减少（-3.5±2.7天；p<0.001），从基线到第12个月受试者每日阿片类药物使用量减少了6.7±29.0吗啡当量剂量（p = 0.013）。平均BPI干扰评分（QOL）较基线提高了2.7±2.7分（p<0.001）。非严重AE和严重AE的发生率分别为72%（130/180）和42%（76/180）；180名受试者中有15名（8%）发生了与装置相关的严重AE。
总体而言，直接作用于受损外周神经的HFNB为下肢截肢慢性PAP患者提供了持续的、按需的急性PAP加重缓解，减少了阿片类药物的使用，并改善了生活质量。
