Anaphylaxis to Mivacurium

We describe a patient who suffered cardiovascular collapse and bronchospasm following induction of anaesthesia.This was demonstrated by subsequent intradermal testing to be the result of anaphylaxis to the new nondepolarizing muscle relaxant mivacurium.To our knowledge, anaphylaxis to mivacurium has not been previously described. CASE HISTORYA 49 kg twelve-year-old boy presented with right iliac fossa pain and was diagnosed as having appendicitis with perforation.Past medical history included an apparently uneventful anaesthetic for tonsillectomy at another hospital.The patient received papaveretum, hyoscine, thiopentone, suxamethonium and halothane at that time.He did not receive a nondepolarizing muscle relaxant.On another occasion, several years previously, he had experienced an isolated episode of wheeze, although no diagnosis of asthma had been made.He was taking no medications.It was elected to perform a modified rapid sequence induction including pre-oxygenation and application of cricoid pressure.Fentanyl 1.0 µg.kg -1 and metoclopramide 0.1 mg.kg -1 were given via an intravenous crystalloid infusion running through a 22 gauge cannula in a forearm vein.Subsequently propofol 2.6 mg.kg -1 containing lignocaine 1.0 mg/ml was given followed by mivacurium 0.2 mg.kg -1 .Immediately after induction the patient coughed, and perioral pallor was seen.The patient's lungs were *M.R.