Subsequent general anaesthesia in patients with a history of previous anaphylactoid/anaphlactic reaction to muscle relaxant

Of 151 patients with a possible anaphylactoid/anaphylactic reaction to a muscle relaxant investigated over a 20-year period follow-up for any subsequent general anaesthesia was complete in 145 (96%). One hundred and twenty-two anaesthetics in 72 patients were documented There were no anaesthetic-related deaths. No subsequent reactions were seen if muscle relaxants were not used in the subsequent anaesthetic nor were they in patients with severe reactions if the original intradermal rest had been equivocal or negative. In the patients with a severe reaction and a positive intradermal test to one or more muscle relaxants, six: out of 40 later anaesthetics using muscle relaxants were associated with clinical problems, three being probable anaphylactic reactions whilst three were minor: Intradermal testing should be performed prior to surgery in this group of patients for the muscle relaxant(s) planned or an anaesthetic technique which avoids relaxants should be used. This review should encourage other centres to under-take similar follow-up.