Case report
A 19-year-old female presented with abdominal pain for three days. She had colicky pain around the umbilicus with low grade fever and then migratory pain for one day. She denied history of past illness or drug allergy. Her physical examination showed normal appearance, and her lungs and heart were normal. Her abdomen revealed no distension, hypoactive bowel sound, soft, moderate tenderness at right lower quadrant area with localized guarding without mass. Completed blood clot showed leukocytosis with shift to the left (white blood cell 18350, PMN 81%), no anemia and normal platelet count. The urinalysis was normal and urine pregnancy test showed negative. Her computed tomography of the abdomen revealed retrocecal type acute appendicitis with focal nonenhanced wall at the appendiceal tip. She received a diagnosis of gangrenous appendicitis and was sent to operating theater for emergency laparoscopic appendectomy. The baseline vital signs included a blood pressure of 125/75 mmHg, a regular sinus rhythm heart rate of 120 beats/min, and peripheral oxygen saturation of 99%. Propofol (120 mg), succinylcholine (100 mg) and fentanyl (100mcg) were administered intravenously, and the trachea was intubated using a 7.0 mm cuffed endotracheal tube. Anesthesia was maintained using 1 L/min O2, 1 L/min Air, and 2.5-3.0 vol% sevoflurane. During procedure, she presented persistent sinus tachycardia (heart rate 130-140 beats/min) and fever (body temperature 39°C). Fever was treated using intravenous paracetamol 1000 mg and cool pack. However, the ETCO2, maintained between 30-35 mmHg, had no signs of inadequate anesthesia and malignant hyperthermia. The anesthetist and surgeon discussed her tachycardia after treatment of dehydration and pyrexia. We suspected thyrotoxicosis and remained cautious regarding complications from this issue, e.g., the thyroid storm. The operation took approximately 1 hour and proceeded unremarkably. The neuromuscular blocker was then reversed using 2.5 mg neostigmine and 0.4 mg glycopyrrolate. Extubation was performed without complication. When the patient completely recovered from anesthesia, she was transferred to the PACU. At the ward, the patient presented BP of 140/100 mmHg, 100% SpO2, and the ECG showed sinus tachycardia with a HR of 140 beats/min. Complete physical exam found mild thyroid gland enlargement with thyroid built positive. She did not have palpitation or syncope. She had history of unintentional weight loss for 17 kg over 4 months. Her thyroid function test revealed FT4 >7.77 ng/dL (0.93-1.7), FT3 13.1 pg/mL (2-4.4) and TSH <0.005 mIU/L (0.27-4.2). The endocrinologist was consulted to co-evaluate and found the cause of severe thyrotoxicosis suspected from post iodine-contrast injection. The Burch Warsofsky point was 45 (impending storm) and thyroglobulin antibody (TgAb) was 16.1 IU/L (0-1.75). Her medications were PTU loading then switched to methimazole, intravenous hydrocortisone total 1 day and propranolol. Her clinical conditions had been observed for two days then she was discharge without complications. Her appendectomy wounds were completely healed, and the pathological report was ruptured appendix. The written informed consent of publication for the case details in this report has been obtained. At 6 months, her clinical conditions improved. Her weight was regained, and her thyroid function test showed FT4 5.02 ng/dL, FT3 13.3 pg/mL and TSH <0.005 mIU/L. Her current medications were methimazole (5) 3 tabs per oral bid and propranolol (40) 1-tab po bid. She was followed up at endocrine clinic regularly every 3 months.