A 54-year-old man presented to the hospital with dyspnea after inhaling butane gas while melting a water pipe during winter. On physical examination, late inspiratory crackles were evident in both auscultated lower lung fields. His history showed no lidocaine allergy, allergic rhinitis, asthma, or allergies to other drugs. On examination, blood pressure was 125/75 mmHg, pulse was 65 beats per minute, oral temperature was 36.5℃, respiratory rate was 18 breaths per minute, oxygen saturation was 76.0%, pH was 7.27, PaO2 was 46.0 mmHg, and PaCO2 was 47.2 mmHg, as the patient breathed ambient air. Total IgE was 129 kU/L. An electrocardiogram revealed a normal sinus rhythm. A pulmonary function test revealed forced expiratory volume in 1 second/forced vital capacity (FEV1/FVC) of 78%, FVC of 2.24 L (60%), FEV1 of 1.75 L (62%), and a diffusing capacity for carbon momoxide of 15.1 mL/mmHg (71%) indicating a restrictive pattern. Chest radiographs revealed bilateral patchy opacities, more in the right lung than in the left lung. Computed tomography of the chest revealed multifocal consolidation and ground-glass opacities in all lobes of both lungs, indicating an acute inhalation lung injury (). The patient recovered after oxygen and supportive care. On the fifth day, we planned to conduct a bronchoscopy to diagnose an inhalational lung injury. We used lidocaine aerosol as local anesthesia for reducing the gag reflex. After administering the lidocaine anesthesia, the patient complained of dizziness without urticaria and angioedema and shortness of breath, which was associated with an increased respiratory rate and decreased oxygen saturation. Coarse expiratory wheezes were auscultated on a physical examination. Blood pressure subsequently dropped, and a radial pulse was not palpable. The patient was treated with nebulized salbutamol and systemic steroid. However, the patient did not recover, and blood pressure continued to decrease accompanied by an increase in respiratory rate and a decrease of oxygen saturation () followed by cardiorespiratory arrest. Cardiopulmonary resuscitation (CPR) with epinephrine, inotropics, and fluid therapy was performed immediately, and the patient was admitted to the intensive care unit under tracheal intubation and ventilator treatment. After 2 hours, his CPR tryptase level was 1.68 µg/L. He was extubated safely on the third post-CPR day.
A 46-year-old female patient, weighing 72 kg, reported to our outpatient department with the chief complaint of pain in the lower left back tooth region for 1 week. Pain was intermittent and sharp in nature. On examination, a grossly decayed 38, which was tender on percussion, was noted. Atraumatic extraction of the tooth was performed under local anesthesia using 2% lidocaine with 1:80,000 adrenaline. After 1.5 h post-operatively, the patient presented erythema and mild swelling on the left side of the face, extending from the zygomatic arch region superiorly to the mandibular inferior border inferiorly and from the corner of the mouth anteriorly to the angle of the mouth posteriorly (). The patient had mild itching with stable vitals and no other typical allergy symptoms (discomfort, choking, or loss of consciousness). Considering her clinical presentation, hypersensitivity reaction was suspected, for which 1–2.5 mg/kg steroid (hydrocortisone) was administered and tablet fexofenadine 180 mg once daily prescribed for 3 days. The erythema and itching was relieved with medication. The Department of Allergy confirmed hypersensitivity response to lidocaine, procaine, and mepivacaine.