Effectiveness of Analgesia of Combined Femoral and Sciatic Blocks Versus Epidural Anesthesia for Lower Limb Amputations

Background: Peripheral neural blockade appears to provide effective analgesia compared with central neuraxial techniques. We compared both techniques as an anesthesia plan for unilateral lower limb amputations.Aim of Work: Comparing of onset of sensory and motor block sufficient to perform the surgical procedure. Assessment of duration of post-operative analgesia using Visual Analogue Score (VAS), incidence of intra operative and post-operative complications, and risk of failure: Complete failure, patchy or single block only.Patients and Methods: Eighty patients, undergoing unilateral lower limb amputations were prospectively randomized to receive either combined femoral and sciatic nerve blocks (single shot each) or lumbar epidural anesthesia. Combined femoral sciatic block group (n=40) received isobaric bupivacaine 0.375% (femoral 20ml and sciatic 20ml) with nerve stimulator guidance. While epidural group (n=40) received isobaric bupivacaine 0.375% using loss of resistance to air technique for space detection then 5-mL aliquots were given to attain a sensory level at T10 which is adequate for lower limb amputation surgery. Block onset time, visual analogue pain scores and first time to ask for analgesia were recorded postoperatively and perioperative complications were also assessed.Results: The onset of epidural block was significantly shorter. However, statistically and clinically significant more prolonged post-operative analgesia was noted with femoral sciatic block group. There was no major difference in peri-operative complication within first 24h, apart from shivering with epidural group and non-significant higher failure rate with femoral-sciatic block group.Conclusion: The use of combined femoral-sciatic nerve block is superior in prolonged post-operative analgesia to conventional epidural analgesia in patients undergoing unilat-eral lower limb amputations. However, block onset is faster and success rate is better in epidural block.