Ultrasound-Guided Versus Peripheral Nerve-Stimulator-Guided Supraclavicular Brachial Plexus Block for Elective Upper-Limb Surgery: An Observational Comparative Study

Abstract

Background: Ultrasound (USG) visualisation of the brachial plexus has revitalised the supraclavicular approach, yet many centres still use peripheral-nerve stimulators (PNS). High-quality comparative data remain limited.

Methods: In a single-centre observational study, 84 ASA I–II adults undergoing elective upper-limb surgery were randomised to USG (n = 42) or PNS (n = 42) guidance. Primary outcomes were block-execution time and success rate. Secondary outcomes were onset of sensory and motor block and complications. Thirty millilitres of 0.5 % bupivacaine + 2 % lignocaine (1:1) were injected in both groups. Data were analysed with Wilcoxon-Mann-Whitney, t-test or χ² as appropriate; p < 0.05 was significant.

Results: Groups were comparable for age, sex and baseline vitals. Median block-execution time was shorter with USG (6 min [IQR 5–6.8]) than PNS (7 min [6–9]; p < 0.001). Motor-block onset was faster with USG (median 8 min [7.3–9] vs 9 min [8–9]; p = 0.019). Sensory-block onset did not differ (≈5.5 min, p = 0.51). Success reached 97.6 % with USG and 92.9 % with PNS (ns). One vascular puncture occurred in PNS; no pneumothorax or neurological injury was noted.

Conclusion: For supraclavicular blocks, ultrasound shortens execution time and hastens motor blockade while maintaining a high success rate and safety profile. These findings support adopting US guidance where resources allow.