Evaluation of the analgesic effect of 2 doses of verapamil with bupivacaine compared with bupivacaine alone in supraclavicular brachial plexus block

Background: Different adjuvant drugs have been used with local anesthetics in order to decrease the time of onset and elongate the duration and quality of regional blocks. This study was performed to study the effects of one of the adjuvants, verapamil, in supraclavicular block. Methods: In this double blinded clinical trial, we divided 60 ASA class I and II patients who were to undergo upper extremity surgery (aged between 18-40 yrs) into 3 different groups randomly. In group I the patients received 30ml Bupivacaine 0.5% plus 2ml normal saline for injection. Group II included patients who received 30ml bupivacaine 0.5% plus 2.5mg verapamil locally and 1ml normal saline for injection. In group III the patients got 30ml bupivacaine 0.5% plus 5mg of local verapamil. All blocks were performed through a supraclavicular brachial plexus procedure, and time of initiating sensory and motor blocks and onset of complete anesthesia and also blood pressure alterations and heart rates were studied and taken into consideration. For data analysis we used SPSS 11.5 software. Results: Our results clarified that verapamil decreased the onset time of anesthesia, motor block and total anesthesia but there was no statistical difference between 2.5 and 5mg doses of verapamil (P>0.05). Among patients who received verapamil in the block, variation of more than 20% from baseline wasn’t detected in blood pressure and heart rate. Conclusion: According to our findings, verapamil causes a decrease in onset times of sensory and motor block and the initiation of complete anesthesia of bupivacaine in supraclavicular block, but there were no significant differences between groups II (verapamil 2.5mg) and III (verapamil 5mg). Blood pressure and heart rate fluctuations were not more than 20% in group II and III.