Impact of ultrasound-guided popliteal sciatic nerve block on endovascular therapy for below-the-knee lesions in chronic limb-threatening ischemia.

Abstract

This study aimed to investigate the impact of ultrasound-guided popliteal sciatic nerve block (PSNB) on the outcomes of endovascular therapy (EVT) for below-the-knee (BTK) lesions in patients with chronic limb-threatening ischemia (CLTI). This single-center retrospective observational study enrolled 180 consecutive patients with CLTI (median age, 75 years [interquartile range (IQR), 43-95 years]; male, 77.8%; diabetes mellitus, 66.7%; dialysis, 52.8%) who underwent EVT for BTK lesions between July 2024 and June 2025. PSNB was introduced at our institution in March 2025. We compared 73 consecutive patients treated with PSNB from March to June 2025 (PSNB group) with 107 consecutive patients treated without PSNB from July 2024 to February 2025 (non-PSNB group). The end points included technical success, procedure time, failure rate of digital subtraction angiography owing to leg motion, contrast volume, radiation exposure (cumulative dose-area product), and PSNB-related complications. Propensity score matching was performed to reduce the baseline differences. Propensity score matching extracted 65 pairs with no significant baseline differences between the groups. There was no significant difference in technical success between the PSNB and non-PSNB groups (96.9% vs 96.9%; P > .99). The total room time was comparable (57 minutes [IQR, 28-157 minutes] vs 60 minutes [IQR, 22-190 minutes]; P = .26), but the procedure time from puncture to sheath removal was significantly shorter in the PSNB group (46minutes [IQR, 14-149minutes] vs 53 minutes [IQR, 18-184 minutes]; P = .02). The median duration required to perform PSNB was 7 minutes (IQR, 2-15 minutes). The failure rate of digital subtraction angiography imaging owing to leg movement was significantly lower in the PSNB group (18.5% vs 53.8%; P < .001). Although contrast volume tended to be lower in the PSNB group (51 mL [IQR, 0-210 mL] vs 65 mL [IQR, 13-241 mL]; P = .22), the cumulative dose-area product was significantly lower in the PSNB group (7.1 Gy·cm² [IQR, 1.7-32.7 Gy·cm²] vs 8.6 Gy·cm² [IQR, 2.5-69.6 Gy·cm²]; P = .02). No PSNB-related complications were observed. Ultrasound-guided PSNB appears to be a safe and effective adjunct during EVT for BTK lesions in CLTI, contributing to shorter procedure times, improved imaging success by minimizing leg movement, and decreased radiation exposure.