Brachial Plexus Block with Ropivacaine, Effects of Added Alpha Adrenergic Agonists - Comparison between Clonidine and Epinephrine

BACKGROUND To improve the time of regional anaesthesia many methods have been used. Epinephrine continues to be the most commonly used drug for this purpose. We wanted to compare the effects of alpha-adrenergic agonists clonidine and adrenaline as an adjuvant to ropivacaine in blocking brachial plexus by the supraclavicular approach in patients undergoing upper limb surgeries. METHODS It is a prospective randomised comparative study conducted for 18 months in 40 patients randomly divided into group RA and group RC, conducted on American Society of Anesthesiology (ASA) I and II patients undergoing upper limb surgeries under supraclavicular brachial plexus block. In group RA 30 mL of 0.5 % ropivacaine with 5 microgram / mL of epinephrine was given and in group RC 30 mL of 0.5 % ropivacaine with 1 microgram / Kg of clonidine was given. RESULTS On comparing effects of added alpha-adrenergic agonists clonidine and epinephrine to ropivacaine for supraclavicular brachial plexus block, it was found that there was no significant difference in the onset of the sensory blockade and motor blockade in the two groups. Duration of sensory blockade was significantly more in the clonidine with ropivacaine group when compared with the epinephrine and ropivacaine. There was no significant difference in haemodynamic responses between the two groups. CONCLUSIONS Supraclavicular approach brachial plexus block is effective in terms of cost and performance, and the margin of safety along with good postoperative analgesia. Hence, it can be concluded that the addition of 1 µg / Kg of clonidine to 0.5 % ropivacaine in supraclavicular brachial plexus block provides a longer duration of analgesia as compared to 5 µg / mL of epinephrine added to 0.5 % ropivacaine. KEYWORDS Ropivacaine, Supraclavicular Brachial Plexus, Epinephrine