Ultrasound combined with neurostimulation-guided lumbar plexus block in obese patients

Abstract

Objective To assess the efficacy of ultrasound combined with neurostimulation for improving the success rate of lumbar plexus block in obese patients undergoing lower extremity surgeries. Methods We randomized 80 obese patients undergoing lower limb surgeries under lumbar plexus block anesthesia between June, 2016 and June, 2018 into 2 equal groups, in which lumbar plexus block was performed under ultrasound localization (U group) or ultrasound combined with neurostimulation localization (UN group). The findings by ultrasound imaging and the success rate of lumbar plexus were compared between the 2 groups. Results All the 80 patients completed the study. In the U group, the ultrasound visibility score was 11 (range 6-15), and the lumbar plexus was seen in 26 patients; The ultrasound visibility score of the UN group was 11 (5-15), and the lumbar plexus was observed in 23 patients, showing no significant differences between the two groups (P>0.05). In the U group, lumbar plexus block was achieved successfully in 31 cases and failure occurred in 9 cases; successful block was achieved in 38 cases and failure occurred in 2 cases in the UN group, demonstrating a significantly higher success rate in the latter group (P < 0.05). Conclusion Ultrasound combined with neurostimulation can improve the success rate of lumbar plexus block in obese patients.

Keywords

• lumbar plexus block
• neurostimulation
• ultrasound
• obesity