Dexmeditomedine as an adjuvant reduces the minimum effective anesthetic volume of ropivacaine required for supraclavicular brachial plexus nerve block

Background: Dexmeditomidine has been used as an adjuvant with local anaesthetic amides for supraclavicular brachial plexus block for improving the quality and duration of analgesia. We conducted this study to find out that whether as an adjuvant it reduces the minimum effective anaesthetic concentration (MEAC) and minimum effective anaesthetic volume (MEAV). Materials and Methods: 90 patients undergoing upper limb surgery were randomized into three groups and given ultrasound guided supraclavicular block. Group A received 30 ml of 0.5% Ropivacaine, Group B received 20 ml of 0.5% ropivacaine with 50 mu gm dexmeditomidine and Group C received 15 ml of 0.5% ropivacaine with 50 mu gm of dexmeditomidine. The onset of sensory and motor block, the duration of sensory and motor block, quality of analgesia, haemodynamic and sedative parameters were recorded. SPSS software was used for statistical analysis. Results: The onset of sensory block in Group B(9.47 +/- 3.54mins) and Group C (12.45 +/- 3.86) was faster in comparison to Group A(17.64 +/- 5.36) which was statistically significant. The duration of the block was also more in Group B and C in comparison to Group A. The requirement of rescue analgesia was also less in Group B and C. There were no statistically significant changes in the haemodynamic parameters and sedation scores. Although the patients of Group C received lesser volume and dose of ropivacaine than Group B, there was no statistically significant delay in onset or duration of sensory and motor block neither any change in the quality of analgesia. Conclusion: We concluded that 15 ml of ropivacaine with 50 mu gm of dexmeditomidine is adequate for good quality of analgesia with no compromise on onset of analgesia and duration of block..