Popliteal sciatic nerve block in the endovascular management of critical limb ischaemia: a UK single-centre experience

Abstract

Objective: This study aims to assess the safety and efficacy of the use of popliteal nerve block (PNB) in the endovascular management of patients with critical limb threatening ischaemia. Design: Single-centre retrospective observational study. Methods: All patients with rest pain who received PNB from March 2018 to August 2021 were included. Pain scores were recorded before and after block using a visual analogue scale (VAS). Requirements for analgesia or sedation, complications related to nerve block, and level of intervention were recorded. Results were compared with a historical cohort of patients prior to implementation of nerve blocks. Results: 68 nerve blocks were performed in 63 patients (M:F 46:17) of mean age 71.7 years (range 43–91). All patients were Fontaine classification III–IV. Sonographically, all nerve blocks were technically successful. The mean VAS pain score was 8.2 pre-block, reducing to 0.3 (p<0.0001) post-block. There were no complications related to the block. Four patients required supplementary analgesia for breakthrough ischaemic pain. Compared with the historical comparison group of patients (n=62), there was a statistically significant reduction in the requirement for conscious sedation (p=0.004) and no procedures were abandoned due to pain compared with three in the historical comparison group (p=0.034). Conclusion: Popliteal sciatic nerve block is safe and effective in patients with critical limb threatening ischaemia undergoing lower limb endovascular intervention, significantly reducing the need for conscious sedation and risk of procedural abandonment.