Antibiotics Are the Most Commonly Identified Cause of Perioperative Hypersensitivity Reactions.

Background: Hypersensitivity reactions (HSRs) during the perioperative period are unpredictable and can be life threatening. Prospective studies for the evaluation of perioperative HSRs are lacking, and data on causative agents vary between different studies.

Objective: The objective of this study was to prospectively determine the success of a comprehensive allergy evaluation plan for patients with HSRs during anesthesia, including identification of a causative agent and outcomes during subsequent anesthesia exposure.

Methods: All patients referred for a perioperative HSR between November 2013 and March 2015, from a Boston teaching hospital, were evaluated using a standardized protocol with skin testing (ST) within 6 months of HSR. Comprehensive allergy evaluation included collection of patient information, including characteristics of HSR during anesthesia. We reviewed the results of ST and/or test doses for all potential causative medications Event-related tryptase levels were reviewed when available.

Results: Over 17 months, 25 patients completed the comprehensive allergy evaluation. Fifty-two percent (13 of 25) were female with a median age of 52 (interquartile range 43-66) years. The most frequently observed HSR systems were cutaneous (68%), cardiovascular (64%), and pulmonary (24%). A culprit drug, defined as a positive ST, was identified in 36% (9 of 25) of patients. The most common agent identified was cefazolin (6 of 9). After our comprehensive evaluation and management plan, 7 (7 of 8, 88%) patients tolerated subsequent anesthesia.

Conclusions: Cefazolin was the most commonly identified cause of a perioperative HSR in our study population. Skin testing patients within 6 months of a perioperative HSR may improve the odds of finding a positive result. Tolerance of subsequent anesthesia is generally achieved in patients undergoing our comprehensive evaluation.