20 YEARS OF PROGRESS IN THE UNDERSTANDING AND DIAGNOSIS OF ALLERGIC COMPLICATIONS OF GENERAL-ANESTHESIA

The incidence of peranesthetic anaphylactoid reactions is currently assessed at 1/3,500 anesthetias, taking all mechanisms together, and 1/6,500 when the mechanism is allergic (anaphylactic reaction). Immunoglobulin E-dependent anaphylaxis is found in 52 % of patients tested. Curarizing agents are responsible for 70 % of anaphylactic shocks. All can be involved : suxamethonium retains its first place, followed by vecuronium. Latex is responsible for 12.5 % of cases of per-anesthetic shock. Shock due to propofol, of immunological origin, has been described but remains very rare (1/45,000 propofol anesthetics). There are known risk factors in the case of latex allergy, but this still remains to be shown as far as curarizing agents are concerned. Mediators (tryptase, histamine, urinary methylhistamine) should be assayed immediately following the adverse event since they are of diagnostic and medicolegal value. The diagnosis of anaphylaxis can be confirmed by skin tests and by assay of specific antibodies to anesthetic agents (thiopental, propofol) as well as to curarizing agents, and latex. No specific premedication against anaphylaxis exists at present. The use of H1 antihistamines is suggested. Properly defined treatment should contribute to a decrease in the severity of these events.