Perioperative Anaphylaxis

Anaphylaxis associated with general anesthesia (AAGA) is a serious perioperative event with significant morbidity and mortality. Appropriate follow-up and investigation of such events is critical to improve the safety of subsequent anesthetics for the individual.

The Association of Anaesthetists of Great Britain and Ireland (AAGBI) has guidelines that state that all suspected cases should be referred to a specialist clinic for investigation. Criteria for referral include unexpected, unexplained hypotension, unexpected bronchospasm resistant to treatment, angioedema, urticaria, severe itch, or widespread erythema. Referrals should include serial serum mast cell tryptase (MCT) measurements and a thorough history of the event.

Whilst the incidence of proven AAGA is given as between 1:1380 and 1:13,000, the incidence of adverse perioperative events that meet the criteria for AAGA is not known. It is thought that such events are more common than reported, and several barriers to referral have been described that may account for this.

We sought to determine the incidence of these events in a multicenter study that involved 12 hospitals. Having gained research and development approval, data were collected about general anesthetics given for elective and emergency surgery between 08:00 and 18:00 hours Monday to Friday, simultaneously in all 12 hospitals, during a 2-week period. Cases where a regional technique was used in addition to general anesthesia were included, but cases where regional anesthesia was the sole technique were not.