Lidocaine: The Origin of a Modern Local Anesthetic

Before the introduction of lidocaine, the choice of local anesthetics was limited Procaine was most commonly used and offered less toxicity than cocaine, but it had a short duration faction Tetracaine had substantial systemic toxicity, limiting its use largely to spinal anesthesia An agent with low toxicity, a quick onset, and a longer duration of action was needed This article reports the initial clinical trials with the newly synthesized lidocaine The first trials were wheal tests on the forearms of human volunteers Lidocaine anesthesia duration was markedly longer than that produced by procaine Lidocaine was first tested for infiltration anesthesia in many short procedures performed in the emergency department, followed by major procedures, including those for goiter and hernia in the operating room Consistent success was observed in both environments Lidocaine was then tested for conduction anesthesia using brachial plexus and mandibular, sacral, and paravertebral blocks Its onset as again substantially faster and longer lasting than that of procaine Lidocaine also provided good spinal and surface anesthesia of the cornea