Prevalence of muscle relaxant sensitivity in a general population: implications for a preoperative screening

Background Muscle relaxants (MR) an responsible for 59% of peroperative ana phylactic reactions. A major issue would be to determine whether a systemat ic preoperative screening in the general population should be recommended. Objective The purpose of the study was to evaluate the prevalence of muscle relaxant sensitivity in a sample of the general population and to assess t he role of possible risk factors. Methods Two hundred and fifty-eight subjects, aged 20-40 years, visiting a health care centre for a check-up were evaluated. Protocol included a quest ionnaire (occupation, symptoms of atopy, previous surgery, history of drug allergy), skin-prick tests to four commercial muscle relaxants and measurem ent of specific IgE against quaternary ammonium ions. Atopy was evaluated b y skin-prick tests to common inhalant allergens and by a Phadiatop test. Results Of the study group, 9.3% had either a positive skin test to one or more muscle relaxant or a presence of specific IgE to quaternary ammonium i ons. No risk factor was identified in the studied group. Conclusion Since the rate of MR sensitivity is much higher than the anticip ated rate of peroperative reactions due to allergy, a systematic preoperati ve screening for MR allergy should not be recommended for adults in a gener al population.