A prospective randomized clinical study to compare the efficacy of 0.25% bupivacaine with clonidine and 0.25% levobupivacaine with clonidine in supraclavicular brachial plexus block for upper limb surgeries

Abstract

:Bupivacaine is an amide local anesthetic, available as a racemic mixture of Dextro and Levorotatory Isomers. Due to its rapid onset and longer duration of anesthesia, It is routinely preferred in various regional anesthetic techniques. However, it is associated with serious cardiovascular and neurological toxicity. Its pure S- enantiomer, Levobupivacaine having similar pharmacological profile is known to have lesser cardiovascular and CNS toxicity. Combining adjuvants like clonidine, a centrally acting partial alpha-2-adrenergic agonist to improve quality of anesthesia is common practice. Hence, the aim of our study is to compare efficacy and safety of 0.25% Levobupivacaine and 0.25% Bupivacaine when combined with clonidine in supraclavicular brachial plexus block for upper limb surgeries.Eighty patients aged between 18 to 60 years with ASA physical status I-II, scheduled for elective upper limb surgeries under were randomized into two groups. Peripheral nerve stimulator guided Supraclavicular brachial plexus block was administered. Group BC received 30ml of 0.25% Bupivacaine plus 1µg/kg Clonidine and Group LC 30ml of 0.25% Levobupivacaine plus 1µg/kg Clonidine. The time of onset of sensory and motor block, duration of sensory and motor block, perioperative hemodynamic parameters, postoperative pain for 24hours and adverse effects were studies.Group LC had faster onset of sensory block (p= 0.014) as well as faster onset of motor block (p= 0.012) compared to group BC. However, durations of sensory block and motor block were statistically not significant in both the groups (p>0.05). Perioperative hemodynamic parameters and assessment of pain during 24 hours of post operative period were comparable and statistically not significant.1mcg/kg of clonidine used as an adjuvant to 30ml of 0.25% Levobupivacaine produces faster onset of sensory and motor block compared to 0.25% Bupivacaine in supraclavicular brachial plexus block. However, similar anesthetic efficacy in terms of duration of sensory and motor block, hemodynamics and postoperative analgesia were observed.