Non-alkalinized and alkalinized 2-chloroprocaine vs lidocaine for intravenous regional anesthesia during outpatient hand surgery

Purpose: Chloroprocaine should be an ideal agent for intravenous regional a nesthesia (IVRA) because of its rapid onset and ester hydrolysis. Raising t he pH of local anesthetics may increase the speed of onset and the intensit y of nerve blocks. We compared plain and alkalinized 2-chloroprocaine 0.5% with lidocaine for IVRA. Methods: in two separate double-blind studies, 78 patients scheduled for da ycare hand surgery, were randomized to receive 40 mt plain 2-chloroprocaine 0.5%, alkalinized 2-chloroprocaine 0.5% or lidocaine 0.5% for IVRA, Time t o sensory and motor block, need for supplemental analgesia, and side effect s were compared. Results: There was no difference in time to sensory or motor block in eithe r group. Patients who received plain chloroprocaine required more supplemen tal opioid and had a higher incidence of metallic taste and of hives than p atients who received lidocaine (P < 0.05). Comparing alkalinized chloroproc aine with lidocaine, there was no difference found with respect to opioid s upplementation, CNS side effects, or incidence of hives. Conclusion: In conclusion, alkalinized chloroprocaine was found to be an ef fective agent or IVRA, but no benefit over lidocaine was detected, Plain ch loroprocaine for IVRA produced more minor side effects than lidocaine.