Bilateral Brachial Plexus Block Using Chloroprocaine For Surgery Of Bilateral Radial Fractures [Response To Letter]

Department of Anesthesiology, New York Presbyterian Brooklyn Methodist Hospital, Brooklyn, NY, USA Dear editor We would like to thank Dr Hendrickson et al for their interest in our work and writing about their opinion. We agree with the comment that mixing local anesthetics might make individual safe doses unknown, so maximum recommended doses of each local anesthetic should not be used. There are no human studies but it can be presumed to be additive based on some animal studies. We mixed local anesthetics in our patients so that we could decrease the volume of more toxic local anesthetics (Bupivacaine) by using some less toxic ones (like chloroprocaine). We also used doses of each local anesthetic of well below the recommended toxic doses and did spacing in our blocks to avoid toxicity. Though axillary blocks along with medial brachial cutaneous and intercostobrachial block can be used, we chose not to perform bilateral axillary blocks because it requires individual blockage of the terminal nerves which might lead to inadequate coverage, and also, performance of the block time and onset time is longer. Instead, we did infraclavicular block on one side, which greatly decreases the chances of phrenic nerve palsy. Dr Hendricken made a very good point of using ropivacaine instead of bupivacaine due to less toxicity, but unfortunately we do not have ropivacaine available at our institution. Lastly, smaller volume of local anesthetics can be used with the use of ultrasound for a successful block. We used 30 mL volume for each block, as we wanted to ensure complete coverage of surgical anesthesia and to avoid any supplementation/ deeper sedation or general anesthesia in case of an incomplete block. Also, our second block was more than two hours later, hence we avoided the overlap of peak plasma concentration of the local anesthetics from first and second blocks.