Rocuronium anaphylaxis and multiple neuromuscular blocking drug sensitivities.

PURPOSE To report a case of anaphylaxis to rocuronium and the sensitivities to multiple neuromuscular blocking drugs in a patient with no previous exposure to this group of drugs. We describe the current recommendations for both intraoperative and postoperative testing of these patients. CLINICAL FEATURES A 36-yr-old man was admitted for repair of a ruptured Achilles tendon. Following induction of general anesthesia with fentanyl and propofol, 60 mg of rocuronium were given to facilitate tracheal intubation. He immediately became profoundly hypotensive with impalpable pulses, and blood pressure could not be recorded. Airway pressure increased markedly, and hand ventilation of the lungs became very difficult. His airway was secured and he was successfully resuscitated with 3 mg epinephrine and three litres crystalloid and colloid intravenous fluid therapy. His recovery in the intensive care unit was uneventful and the operation was performed four days later under spinal anesthesia. Subsequent skin prick testing, performed six weeks later, demonstrated strong positive weal and flare reactions to rocuronium, vecuronium and pancuronium, and some cross-reactivity with the benzylisoquinolinium group of muscle relaxants. CONCLUSION Muscle relaxants are responsible for 61.6% of cases of anaphylaxis during general anesthesia. Cross-reactivity is common, as this group of drugs share a quaternary ammonium group. It is mandatory that patients be tested for both the agent responsible and cross-reactivity following an anaphylactic response. We suggest a protocol for investigation of suspected anaphylaxis.