Ultrasound-guided continuous infraclavicular brachial plexus block using bupivacaine alone or combined with adenosine for pain control in upper limb surgery

ABSTRACT

The infraclavicular brachial plexus block [ICB] is designed to deposit anesthetic high in the plexus, achieving anesthesia of the hand, forearm, elbow, and distal arm. Adenosine is a metabolic intermediate that is involved in nearly all aspects of cell function, including neurotransmission and signal transduction.This study was aimed to show whether addition of adenosine to bupivacaine in ultrasound-guided ICB had an analgesic effect. Sixty adult patients were divided into two equal groups, each group included 30 patients. Group I received infraclavicular bupivacaine 0.325% in a volume of 30 ml. Group II received 30 ml of 0.325% bupivacaine + 12 mg adenosine. The block was maintained with an infusion of 10 ml/h. The following parameters were assessed Success rate, time of the sensory onset, motor block, visual analog scale [VAS], and amount of i.v. pethidine needed. This study showed an analgesic effect of infraclavicular adenosine as evidenced by a statistically significant shorter mean time of onset of the sensory block [16 vs. 20 min, P<0.05], lower mean VAS score over 48 h [1.7 vs. 2.7, P<0.05], longer mean time of first parenteral analgesic requirement [299 vs. 255 min, P<0.05], and lower mean total dose of pethidine needed over 48 h after surgery [25.5 vs. 56.6 mg, P<0.05]. All patients got successful infraclavicular block and recovered uneventfully without any sensory or motor deficit. Adenosine may provide valuable addition to the therapeutic options in anesthesia and pain management. Further research is required to figure out its exact role