Prolonged blockade of the sciatic nerve in the treatment of pain in patients with chronic limb-threatening ischemia: prospective longitudinal clinical study

Abstract

BACKGROUND: Systemic multimodal analgesia does not always relieve ischemic pain, and the side effects of its components may be intolerable in patients with comorbid and physically debilitation with chronic limb-threatening ischemia (CLTI). An alternative effective and safe method of pain relief for patients with CLTI is needed.
 OBJECTIVE: To evaluate the efficacy and safety of prolonged popliteal sciatic nerve block in patients with CLTI at the stages of treatment.
 MATERIALS AND METHODS: A prospective clinical study was performed in 31 patients with CLTI. Pain intensity was assessed by a numerical rating scale at the stages of treatment: (1) on admission, (2) presence of systemic multimodal analgesia (paracetamol, ketoprofen, tramadol, and morphine), (3) after catheter insertion to the popliteal sciatic nerve and prolonged nerve block with 0.5% ropivacaine solution, (4) after revascularization without anesthesia, (5) after revascularization in the presence of nerve blockade, and (6) upon discharge. Catheter insertion was performed under ultrasound control and neurostimulation. Pain intensity, frequency of insomnia, and forced lowering of the limb, need for narcotic analgesics, and patient satisfaction with treatment were assessed.
 RESULTS: Regional block before surgery provided better pain relief than systemic multimodal analgesia (p 0.001) and reduced the need for narcotic analgesics (p 0.001). Insomnia was observed less frequently with prolonged blockade of the sciatic nerve than with systemic multimodal analgesia (p 0.05), as well as forced lowering of the limb (p 0.05). Revascularization of the lower extremity has an analgesic effect; however, pain relief is required for most patients. Pain relief through sciatic nerve block at all stages of CLTI treatment, sleep normalization, and freedom from forced posture improved the quality of life and satisfaction with treatment. No complications associated with the regional blockade were recorded.
 CONCLUSION: Prolonged popliteal sciatic nerve block effectively relieves pain in patients with CLTI, is safe, and can be an alternative to systemic anesthesia.