Clonidine as an Adjuvant to 0.5% Ropivacaine for Ultrasound-Guided Supraclavicular Brachial Plexus Block in Upper-Limb Surgeries: A Randomised Prospective Study

Background and Aims; Ultrasound-guided supraclavicular brachial plexus block provides effective anaesthesia and postoperative analgesia for upper-limb surgeries. Ropivacaine is favoured due to its safer pharmacological profile, and adjuvants such as clonidine may enhance block characteristics. This study aimed to compare the efficacy of 0.5% ropivacaine alone with 0.5% ropivacaine plus clonidine (1 µg/kg) for ultrasound-guided supraclavicular brachial plexus block.

Methods; This prospective, randomised controlled study included 80 adult patients (ASA I–II), aged 18–60 years, scheduled for elective upper-limb surgeries. Patients were allocated into two groups: Group R (n=40) received 20 mL of 0.5% ropivacaine, and Group RC (n=40) received 20 mL of 0.5% ropivacaine with clonidine 1 µg/kg. Blocks were performed under ultrasound guidance. Primary outcomes were onset and duration of sensory and motor block and duration of postoperative analgesia. Secondary outcomes included visual analogue scale (VAS) scores, haemodynamic parameters, rescue analgesic requirement, and adverse effects.

Results; Demographic variables and baseline haemodynamic parameters were comparable between groups. The onset of sensory (6.3±1.5 vs. 7.5±1.1 min) and motor block (10.9±1.5 vs. 13.2±1.8 min) was significantly faster in Group RC (p<0.001). Duration of sensory block (11.3±1.1 vs. 5.0±0.4 h), motor block (9.7±1.1 vs. 4.5±0.3 h), and analgesia (12.8±1.3 vs. 5.4±0.6 h) were significantly prolonged in Group RC (p<0.001). VAS scores were significantly lower at 4 and 8 hours, and rescue analgesic requirement was reduced in Group RC (p<0.001). No significant adverse effects were observed.

Conclusion; Clonidine (1 µg/kg) added to 0.5% ropivacaine significantly improves block quality and prolongs postoperative analgesia without added adverse effects.