D3.66 - National Survey on Perioperative Hypersensitivity Reactions: Clinical and Epidemiological Insights from Spanish Hospitals

Perioperative hypersensitivity reactions (PHRs) are a clinical challenge with potentially severe consequences for patients. The PHR Interest Group (GIRHP) of the Allergy Drug Committee of the Spanish Society of Allergy and Clinical Immunology (SEAIC) survey to evaluate the epidemiological characteristics and management of PHRs among Spanish allergists

A survey was designed and distributed through the SEAIC newsletter and social media platforms to gather data on PHR practices across Spanish hospitals.

Out of 473 recorded interactions, 242 complete responses were analyzed.

Case Volume: The mean number of PHRs managed by respondents in the past year was 5.74 (SD 6.13), with a median of 4 cases. Only 2.1% of allergists managed more than 20 cases.

Demographics: 76.4% of cases occurred exclusively in adults, while 15.5% involved less than 10% of paediatric cases.

Severity Classification: Brown's criteria were most commonly used (40.3%), followed by the EAACI 2019 guidelines (38.6%). The mean frequency of severe reactions reported was 27.2%.

Referral Timing: The average time from reaction to allergy consultation was 32.44 days (SD 39.13), ranging from 1 to 365 days. Notably, 25% of patients were seen within 10 days, indicating that some hospitals have rapid referral processes.

Diagnostic Approach: Most hospitals utilized a combination of clinical history, skin tests (99%), specific IgE tests (82.7%), and basal serum tryptase measurements (78.2%). However, less than 50% obtained acute-phase tryptase. The majority of respondents (77.5%) adhered to the >1.2 + 2x BASAL tryptase criterion for evaluating tryptase elevation, in alignment with international guidelines such as those from the EAACI."

Etiology Identification: A cause was identified in less than 60% of cases by most respondents. Despite this, 75.3% of allergists continued to investigate all suspected drugs, even after identifying a primary culprit.

Causative Agents: Antibiotics were implicated in 66.3% of cases, followed by muscle relaxants (17.6%) and NSAIDs (11.6%).

PHRs are rare but pose significant challenges in diagnosis and management. Enhanced continuous education, wider dissemination of clinical practice guidelines, and strengthened collaboration between allergists and anaesthesiologists are essential to improving outcomes.