Drugs and Other Agents Used in Anesthesia and Surgery

Abstract

Neuromuscular blocking drugs (NMBDs) are the most common cause of anaphylaxis during anesthesia representing ~60 % of reactions and an incidence of 1 in 1,000–20,000. Reactions are mediated by IgE antibodies with specificity for tertiary and quaternary ammonium ions, but adjoining structures may also be recognized. Recognition of the substituted ammonium groups accounts for the extensive cross-reactivity between the NMBDs. Diagnosis of reactions is effected by skin testing with free drugs, IgE antibody assays (especially using a morphine-solid phase), and the tryptase assay. Reversal of rocuronium-induced NM block with the cyclodextrin sugammadex has highlighted the question of changed allergenicity of such chemically sequestered drugs in host–guest complexes. Anaphylactic reactions to the hypnotics thiopentone and propofol are rare. Both are diagnosed by skin testing and the former also by a specific IgE test. True IgE-mediated reactions to local anesthetics are extremely rare; many reactions appear to be vasovagal responses, but delayed reactions are well known. Anaphylactic and other adverse reactions occasionally occur to colloids such as hydroxyethyl starch, gelatin, and dextrans, to the polypeptides protamine and aprotinin, and to heparins and patent blue V. Pre-injection of small MW dextran 1 reduces the incidence of dextran-induced anaphylaxis from 25 to 3 per 100,000.