When I first learned digital nerve blocks in the late 1990’s I was taught to mix Lidocaine and Bupivacaine 50/50 to provide faster onset (Lidocaine) and a longer duration of action (Bupivacaine). My use of two agents for digital nerve blocks was recently questioned by one of my colleagues.
Any time additional medications are drawn up into a syringe there is opportunity for error, and there is additional time added to the procedure. A review of the (limited) literature will try to answer the following questions:
- Does the addition of Lidocaine to Bupivacaine decrease the time to onset of anesthesia?
- Does the addition of Lidocaine to Bupivacaine decrease the pain of injection?
- Does the use of Lidocaine with Epinephrine prolong the duration of digital block long enough to obviate the need for Bupivacaine?