Perioperative Management of Local Anesthetic Allergies

Local anesthesia is defined as the temporary loss of sensation to a targeted area of the body conferred by a topically-applied or locally-injected anesthetic agent—or local anesthetic (LA)—that provides pain prevention or reduction without inducing loss of consciousness. 1 Malamed S.F. Handbook of Local Anesthesia. 4th ed. Harcourt Brace, 1998 Google Scholar LAs function at the level of afferent nociceptive (pain) neurons, where these agents enter pain neurons and bind to voltage-gated sodium channels located on the cytoplasmic surface. LA binding prevents the opening of voltage-gated sodium channels and subsequent influx of sodium into the neuron, which blocks the neuron’s depolarization and propagation of pain impulses to the brain. Since conduction of the pain signal is stopped before reaching the brain, the painful trigger will not be registered, resulting in loss of sensation to the area supplied by the affected nerves. 2 Taylor A. McLeod G. Basic pharmacology of local anaesthetics. BJA Educ. 2020; 20: 34-41 Abstract Full Text Full Text PDF PubMed Scopus (58) Google Scholar