A Comparative Study of Effect of 0.25% Levobupivacaine with Dexmedetomidine versus 0.25% Levobupivacaine in Ultrasound-Guided Supraclavicular Brachial Plexus Block

CONTEXT: Dexmedetomidine, an α(2)-agonist, has been studied widely as an adjuvant to local anesthetics in regional anesthesia techniques to enhance the quality and duration of analgesia (DOA). It was hypothesized that addition of dexmedetomidine 0.5 ug.kg(‒1) to levobupivacaine would prolong the DOA. AIMS: We aimed to evaluate the efficacy of dexmedetomidine as an adjuvant to levobupivacaine in supraclavicular brachial plexus block with respect to onset and duration of sensory and motor blockade, and duration of analgesia. SETTINGS AND DESIGN: This was a prospective randomized double-blind study carried out at a tertiary hospital attached to medical college. SUBJECTS AND METHODS: Sixty American Society of Anesthesiologists PS Class I and II patients aged between 18 and 60 years of either sex, undergoing elective upper-limb surgery lasting more than 30 min, were included in the study. They were randomly divided into two groups of thirty each to receive ultrasound-guided supraclavicular brachial plexus block. Group L was given nerve block with 20 mL of 0.25% levobupivacaine and 1 mL saline, and Group D received 20 mL of 0.25% levobupivacaine with 0.5 ug.kg(‒1) of dexmedetomidine (diluted to volume of 1 mL). Onset time and duration of sensory and motor blockade, time to first rescue analgesia, and hemodynamic parameters were recorded. STATISTICAL ANALYSIS USED: Chi-square test for qualitative variables and Student's unpaired “t“ test for continuous variables were used for statistical analysis. RESULTS: The onset of sensory and motor blockade was 6.51 ± 0.77 min and 10.71 ± 0.34 min in Group D and 9.9 ± 0.45 and 15.93 ± 1.92 min in Group L, respectively (P < 0.005). DOA was 9.53 ± 0.29 h in Group D and 3.89 ± 0.30 h in Group L (P < 0.001). The duration of sensory and motor block was 9.14 ± 0.19 h and 8.55 ± 0.31 h in Group D and 6.15 ± 3.02 and 5.61 ± 2.98 h in Group L, respectively (P < 0.005). No adverse effects were observed in either of the groups. CONCLUSIONS: Addition of 0.5 ug.kg(‒1) of dexmedetomidine to 20 mL 0.25% levobupivacaine in ultrasound guided (USG)-guided supraclavicular brachial plexus block shortens the onset time of sensory and motor blockade and prolongs duration of sensory and motor block and DOA.