000710 - Severe Immediate Hypersensitivity Reaction to Oxybuprocaine During Preoperative Skin Testing in a High-Risk Patient

Background:Local anesthetics are widely used in ophthalmologic procedures, and allergic reactions to ester-type anesthetics such as oxybuprocaine are considered rare. However, patients with a history of multiple drug allergies and anaphylaxis represent a high-risk group requiring careful evaluation prior to surgery.

Case Presentation:We report the case of a 72-year-old female referred for preoperative allergy testing prior to cataract surgery. Her medical history was notable for multiple severe hypersensitivity reactions, including documented anaphylactic shock to iodinated contrast media (Odiston) in 1982 and 1983, anaphylaxis following COVID-19 vaccination in 2021, and reported allergies to lidocaine (xylocaine), aspirin, codeine, tetracycline, fluconazole, and dog epithelia. Comorbidities included arterial hypertension (grade II), peripheral arterial disease, and multiple previous surgeries.

Methods:Skin prick testing was performed using oxybuprocaine hydrochloride at dilutions of 1:10 and undiluted (1:1), with saline as a negative control, according to standard safety protocols.

Results:Approximately 40 minutes after testing, the patient developed acute tongue edema suggestive of an immediate hypersensitivity reaction with glottic involvement. Emergency treatment was promptly initiated, including subcutaneous and intravenous adrenaline, intravenous fluids (normal saline and Ringer’s solution), systemic corticosteroids, antihistamines, and antihypertensive management due to severe blood pressure elevation (230/120 mmHg). Otorhinolaryngology evaluation, including indirect laryngoscopy and videofibroscopy, showed no persistent laryngeal edema or airway compromise. Intensive care consultation confirmed clinical stabilization without respiratory failure.

Conclusion:This case highlights the potential for severe immediate hypersensitivity reactions to oxybuprocaine during skin testing, particularly in patients with a complex allergic background and prior anaphylaxis. Extreme caution, strict monitoring, and availability of advanced resuscitation measures are mandatory when testing local anesthetics in high-risk individuals. Alternative strategies for anesthesia should be considered in such patients.