A Clinical Comparative Study of Dexmedetomidine, Dexamethasone, and Clonidine as Adjuvants to Local Anesthetics in Supraclavicular Brachial Plexus Blocks.

INTRODUCTION

The brachial plexus block is one of the peripheral blocks, beneath which the majority of upper limb surgical procedures are carried out. During upper limb surgery, a supraclavicular nerve block is an excellent substitute for general anesthesia.

AIM

This is a clinical comparative study of dexmedetomidine, dexamethasone, and clonidine as adjuvants to local anesthetics in supraclavicular brachial plexus block.

MATERIAL AND METHODS

Ninety patients with American Society of Anesthesiologists (ASA) grades I and II scheduled for upper limb surgeries were randomly divided into three groups. Group RDEX (ropivacaine + dexmedetomidine; n = 30) received 20 ml of 0.5% inj. ropivacaine with 10 ml of 2% lignocaine and adrenaline with inj. dexmedetomidine 1 µg /kg (32 ml solution). Group RC (ropivacaine + clonidine; n = 30) received 20 ml of 0.5% inj. ropivacaine with 10 ml of 2% lignocaine and adrenaline with inj. clonidine 1 µg /kg (32 ml solution). Group RD (ropivacaine + dexamethasone; n = 30) received 20 ml of 0.5% inj. ropivacaine with 10 ml of 2% lignocaine and adrenaline with inj. dexamethasone 2 ml (8 mg) (32 ml solution).

RESULTS

The onset of sensory and motor block was a statistically significant difference among the three groups (p < 0.001), showing that Group RDEX has the faster onset, followed by Group RC and Group RD as the slowest. There was a statistically significant difference in the mean duration of sensory and motor block among the three groups (p < 0.001), showing that Group RDEX has the longest average duration, followed by Group RC, while Group RD has the shortest. The comparison of the mean duration of analgesia shows a statistically highly significant difference among the three groups (p < 0.001). Dexmedetomidine (RDEX) has the longest duration of analgesia, followed by Group RC and then Group RD. The hemodynamic profile was comparable among the three groups. Sedation was observed in Groups RDEX and RC. Overall, no complications were found in Group RD.

CONCLUSION

Dexmedetomidine, when added to 0.5% ropivacaine for supraclavicular brachial plexus blocks, decreases the time of onset of sensory and motor blockade and prolongs the duration of the block and the duration of analgesia as compared to clonidine and dexamethasone with 0.5% ropivacaine, making it a better adjuvant to ropivacaine for upper limb surgeries.