Comparison of Costoclavicular Block and Infraclavicular Block Effects on Tissue Oxygen Saturation in Upper Extremity Surgery: A Randomized, Assessor-Blinded Controlled Trial.

Study Summary

80 patients undergoing upper extremity surgery were randomized to receive ultrasound-guided costoclavicular block (CCB) or infraclavicular block (ICB), with 77 patients included in the final analysis. Both groups received 30 mL of local anaesthetic consisting of 0.5% bupivacaine and 2% lidocaine. The primary outcomes were tissue oxygen saturation (StO2) and change in tissue oxygen saturation (ΔStO2), measured using near-infrared spectroscopy (NIRS). Secondary outcomes included sensory and motor block assessments and haemodynamic parameters. Outcomes were assessed at baseline and 0, 5, 10, 15, and 20 minutes after block completion. Overall, the results revealed significant increases in StO2 and ΔStO2 in both groups, without consistent between-group differences. Both techniques demonstrated similar sensory and motor block findings and maintained haemodynamic stability. These findings suggested that NIRS-derived tissue oxygenation measurements may provide a useful complementary method for assessing early peripheral nerve block onset.