Perioperative Hypersensitivity Reactions: Diagnosis, Treatment and Evaluation

Abstract

Perioperative hypersensitivity reactions are difficult to diagnose as symptoms are hard to differentiate from the effects of anaesthesia on the cardiovascular and respiratory systems. There are numerous non-allergic differential diagnoses, and subsequent investigations should aim to determine the mechanism behind the reaction. In many cases, an allergic mechanism cannot be ruled out and systematic investigations should be performed of all drugs and substances the patient was exposed to prior to the reaction. Serum tryptase taken at the time of reaction compared with the patient’s own baseline level is helpful in determining whether an IgE-mediated mechanism is likely. In these cases, the culprit drug should be identified to ensure future avoidance of the culprit whilst causing only the necessary restrictions to the choice of future anaesthetic drugs. In recent years, a number of “hidden” and rarely documented allergens have been identified in the perioperative setting and, therefore, all exposures should be identified and tested. Investigations are highly specialised and comprise skin testing, in vitro testing and in some specialised centres, recently, also provocation. A combined approach with cooperation between anaesthesiologists and allergists is necessary to ensure the highest standard of care for patients in this complicated setting.