A study to evaluate the effectiveness of Bupivacaine (0.5%) versus Ropivacaine (0.5%, 0.75%) in patients undergoing upper limb surgery under brachial plexus block

Brachial plexus block is the commonest form of regional anaesthesia being used for upper limb surgeries. Bupivacaine is most widely used local anaesthetic in regional anaesthesia, but its cardiotoxicity has led to the development of a new and safer local anaesthetic agent. Ropivacaine is a pures (−) enantiomer and is less cardiotoxic than equivalent concentrations of bupivacaine has recently introduced for its clinical use. The aim of this study was to evaluate the efficacy of different concentrations of ropivacaine 0.5% and 0.75% as compared to bupivacaine 0.5% in supraclavicular brachial plexus block in upper limb surgeries.

A randomized double blind study was conducted on 60 adult patients of ASA grade I and II, were randomly allocated into three groups of 20 each. Group I and group II received 30 ml of 0.5% and 0.75% ropivacaine respectively and group III received 0.5% bupivacaine in supraclavicular brachial plexus block. Onset and duration of sensory and motor block, sparing of dermatomes and duration of analgesia were studied as primary outcome. VAS scores, analgesic consumption in 24 hours, hemodynamics and side effects were also evaluated as secondary outcome.

Ropivacaine 0.5% and 0.75% produced quick onset of motor and sensory blockade compared to bupivacaine (p<0.05). Duration of sensory and motor blockade was shortest in patients receiving 0.5% ropivacaine compared to 0.75% ropivacaine and 0.5% bupivacaine (p< 0.001). Sparing of dermatomes was present in all the three groups but statistically insignificant (p> 0.05). Pain scores in all three groups were statistically insignificant (p> 0.05). However, total doses of rescue analgesia required was least in group II (1.86 ± 7.86) as compared to group I (3.60 ±8.83) and group III (3.26 ± 8.06) (p< 0.001). There were no significant hemodynamic changes among all the three groups. Incidence of perioperative complications were similar in all the three groups.

To conclude, 0.5% ropivacaine was less effective than 0.75% ropivacaine and 0.5% bupivacaine. Postoperatively although the duration of analgesia was comparable among all the three groups but the total dose of rescue analgesia required was significantly lesser in 0.75% ropivacaine than 0.5% ropivacaine and 0.5% bupivacaine. No significant adverse effects were noted in all the three groups.