Anesthesia Student Survival Guide.pdf - Index of

Pharmacology of Local Anesthetics
John W. Wolfe and Jerome M. Adams
Chapter 6
For maximum impact, it is recommended that the case study and questions found
on page xix are reviewed before reading this chapter.
Key Learning Objectives
● Understand the basic mechanisms of local anesthetic action and metabolism
● Appreciate the differences in the properties among commonly used local
anesthetics
● Learn the signs of local anesthetic toxicity and its treatment
History of Local Anesthetics
Cocaine was the first local anesthetic to be discovered after isolation from coca
leaves by Albert Niemann in the 1860s. Cocaine was first used clinically in 1884
by Sigmund Freud, who used it to wean a patient from morphine addiction.
Freud and Karl Kollar also noticed the anesthetic effects of cocaine, and Kollar
later described its utility as a topical ocular anesthetic. Later in 1884, William
Halsted published a description of the injection of cocaine into a sensory nerve
to provide surgical anesthesia.
Local Anesthetic Mechanism of Action
The cell membrane of a nerve axon contains sodium and potassium channels
that control the flow of ions between the extracellular fluid and the interior of
the cell. Local anesthetics exert their effects by inhibition of sodium channels.
J.M. Ehrenfeld et al. (eds.), Anesthesia Student Survival Guide: A Case-Based Approach,
DOI 10.1007/978-0-387-09709-1_6, © Springer Science+Business Media, LLC 2010
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