No abstract

A 50-year-old woman had experienced 6 months of mild shortness of breath and noise while breathing. She was obese with a body mass index of 32. Her primary care physician found a neck mass; results of a serum thyroid function test were normal. Her symptoms remitted spontaneously, and she ignored advice to seek further evaluation. Six months later, she had her first episode of dyspnea with cyanosis, followed by decreased consciousness. When the ambulance arrived, her Glasgow Coma Scale score was 7 and her peripheral oxygen saturation was 60%. A nonrebreather oxygen mask was applied during transport.On arrival at the emergency department, the patient's respiratory rate was 30 breaths/min, pulse rate was 80 beats/min, blood pressure was 107/61 mm Hg and peripheral oxygen saturation was 76%; her Glasgow Coma Scale score had deteriorated to 6. Blood gas analysis revealed pH 6.7, PCO 2 99.1 mm Hg, PO 2 91.3 mm Hg and HCO 3 11.0 mmol/L, which was consistent with mixed respiratory acidosis and metabolic acidosis. Physical examination showed diffuse rales and some wheezing. After emergent endotracheal intubation, the patient regained consciousness. The endotracheal tube contained copious amounts of a pink frothy secretion. Brain computed tomography scans were normal. Chest radiography done after intubation showed ground-glass opacities bilaterally, suggestive of pulmonary edema ( Figure 1A).Laboratory test results revealed d-dimer levels up to 10.5 (normal < 0.5) µg/mL. Computed tomography of the chest with contrast indicated no filling defect in the pulmonary arteries. There was a nodule visualized that measured 4.0 × 4.5 × 7.0 cm in the right thyroid lobe, with intrathoracic extension (Figure 2). Electrocardiography showed ST segment depressions in leads II, III, aVF, V5 and V6. Further laboratory results were as follows: creatine phosphokinase 527 (normal 26-192) U/L; creatine phosphokinasemyocardial band 40 (normal < 25) U/L and troponin I 1.73 (normal < 0.50) µg/L. Echocardiography showed hypokinesia over the anterolateral and basal septum with an ejection fraction of 40%. Coronary arteriography was normal. Results of thyroid function and virus serologic tests were negative.Subsequent chest radiography, 29 hours after intubation, showed resolution of the interstitial, patchy infiltrations ( Figure 1B). A second echocardiogram showed normal systolic function with an ejection fraction of 62%. The endotracheal tube was removed after weaning criteria were met and after a successful spontaneous breathing trial with a T-piece circuit. Two hours after extubation, the patient had a second episode of respiratory distress accompanied by stridor with hypoxemia and altered consciousness. Her condition was unresponsive to intravenous hydro cortisone and bilevel positive airway pressure ventilation. After reintubation, she recovered immediately. The patient underwent a tracheostomy and was transferred to the regular ward. She had a third episode of respiratory distress with desaturation 12 hours after the tracheostomy tube was re...