34 cases-anesthesia-analgesia.org February 1, 2014 • Volume 2 • Number 3 Copyright © 2014 International Anesthesia Research Society DOI: 10.1097/ACC.0b013e3182a6d491 A n anaphylactic reaction is deined as a severe, life- threatening, systemic, hypersensitivity reaction that is mediated by an immunological mechanism trig- gered by antigen–antibody (immunoglobulin [Ig]E, IgG) interaction or immune complexes. 1 The incidence of ana- phylaxis during anesthesia is 1:5000 to 1:20,000, depending on the deinition and degree of underreporting. 1–3 In anes- thesia, 60% of all severe allergic reactions are triggered by neuromuscular blocking drugs. Other frequent causes are latex (20%), antibiotics (15%), and colloids (5%). 1 Among disinfectants, chlorhexidine and povidone-iodine are the most prominent. 1,4 Here, we report the occurrence of a severe intraopera- tive anaphylaxis to an ingredient in widely used lubricants (Instillagel®, Melisana AG, Switzerland; Endosgel®, Farco- Pharma, Germany), that is, chlorhexidine. The patient reviewed this report and gave written per- mission for publication. CASE DESCRIPTION A 45-year-old ASA physical status I man with a large kidney stone was scheduled for percutaneous nephrolitholapaxy under general anesthesia (irst procedure). Apart from an uncomplicated tonsillectomy as a child, he had no signii- cant medical history and had no known allergies. General anesthesia was induced and maintained using thiopental, fentanyl, rocuronium, and sevolurane. Routine antibiotic prophylaxis, amoxicillin/clavulanic acid 1.2 g IV was given, and the patient’s condition was stable until surgery started 30 minutes later. After disinfecting the surgical ield with povidone- iodine (Betadine®; Mundipharma Medical Company, Switzerland), his bladder was inspected with a cystoscope and a urinary catheter inserted. The renal pelvis was percu- taneously punctured, and iodine-containing contrast media (Hexabrix®, Guerbet AG, Switzerland) was injected. At this time, his arterial blood pressure decreased to a minimum of 75/40 mm Hg but returned toward normal at the next measurement. Three minutes later, his airway pressure sud- denly increased, and the capnogram changed notably, sug- gesting bronchoconstriction. His Spo 2 decreased to 88%, and the patient became severely hypotensive (50/30 mm Hg). In addition, a progressive swelling of his tongue was noted. The operation was stopped, and a generalized erythema was visible after the drapes were removed. Treatment was initiated with epinephrine (50 mcg bolus IV, followed by an epinephrine infusion), an antihistamine (clemastine 2 mg IV), and hydrocortisone (200 mg IV). Ten minutes later, his respiratory symptoms and hemodynamics improved, and the epinephrine infusion was progressively reduced. Because his tongue was enormously swollen, the patient was transferred to the intensive care unit while sedated, and his trachea was extubated 6 hours later. At this time, our hypothesis was that contrast media Hexabrix® may have caused the anaphylactic reaction. The patient was referred to the Allergy and Immunology Clinic, and a complete workup was done 2 months later (Table 1). A type I aller- gic reaction to chlorhexidine and a nonspeciic reaction to propofol were diagnosed. At this time, we were not aware that either chlorhexidine or propofol had been used, and the immunologist suspected the contrast media to have caused the reaction by nonspeciic histamine liberation. Three months later, the patient was rescheduled for the same procedure (second procedure). Because we could not identify the exact agent causing the earlier anaphylac- tic reaction, general anesthesia was instead induced with etomidate, fentanyl, vecuronium, and maintained with sevolurane. Following the recommendations of the immu- nologist, we administered antihistamines (clemastine 2 mg IV and ranitidine 50 mg IV) and hydrocortisone (250 mg IV) as premedication for anesthesia. Antibiotic prophylaxis was done using cefuroxime 1.5 g IV. As in the previous pro- cedure, the patient remained hemodynamically stable until the beginning of surgery. However, just after starting cystos- copy, the patient developed severe bronchospasm, progres- sive swelling of the tongue, and severe hypotension. Again, the operation had to be aborted notably before administer- ing any contrast media. The patient was transferred to the intensive care unit, and the epinephrine infusion with rates as high as 30 mcg·min −1 was stopped 6 hours later. There was generalized erythema, a massive capillary leakage (hemo- globin 18.4·g·L −1 ), severe intraoral, and urethral mucosal swelling, and the trachea remained intubated until the fol- lowing day. The patient was again referred to the Allergy In this case report, we describe a healthy urological patient who suffered severe intraoperative anaphylaxis to chlorhexidine, an ingredient contained in frequently used lubricants (Instillagel®, Endosgel®). Chlorhexidine is a well-known skin disinfectant and antiseptic component in mouth- wash or other over the counter antiseptic pharmaceuticals. There is little awareness that com- monly used lubricants may contain hidden chlorhexidine. After severe intraoperative anaphylaxis, it is important to investigate all potential (including hidden) agents that might have caused this life-threatening reaction. (A&A Case Reports. 2014;2:34–6.) From the *Institute of Anesthesiology and Pain Medicine, and †Department of Urology, Kantonsspital Winterthur, Winterthur, Switzerland. Accepted for publication July 17, 2013. Funding: The study was supported by departmental funds. The authors declare no conlicts of interest. Address correspondence to Michael T. Ganter, MD, Institute of Anesthesiology and Pain Medicine, Kantonsspital Winterthur, Brauerstrasse 15, CH-8401 Winterthur, Switzerland. Address e-mail to michael.ganter@ksw.ch. Severe Anaphylaxis: The Secret Ingredient Andreas Buergi, MD,* Barbara Jung, MD,* Christian Padevit, MD,† Hubert John, MD,† and Michael T. Ganter, MD*