H. R. Swetha1
Background and objectives: Regional anaesthetic technique such as brachial plexus block by supraclavicular approach is widely used for upper limb surgeries. This study compared the addition of potassium chloride to bupivacaine on the onset time and duration of brachial plexus block. METHODS: Sixty patients between 20 - 70 years of either sex of ASA I and ASA II were randomly allotted to one of the two groups of thirty each. Group I received 30ml of 0.375% bupivacaine with 0.2mmol of potassium chloride. Group II received 30ml of 0.375% plain bupivacaine. Sensory blockade were determined by pinprick test in the C4- T2 skin dermatomes, while motor blockade was graded according to the movement of upper limb by the patient. RESULTS: Potassium chloride group showed rapid onset of sensory and motor blockade when compared to other group (p< 0.001). The decreased requirements of adjuvants in potassium group suggest greater quality of blockade with respect to other group. The duration of anaesthesia was prolonged in potassium group in relation to other group (p<0.001). CONCLUSION: These data suggest that addition of potassium chloride to bupivacaine for brachial plexus block significantly decreases onset time, increases depth of blockade and prolongs the duration.