A “lusus naturae” dyspnea

An 85-year-old female patient with a medical history significant for hypertension, chronic kidney disease, renal artery stenosis, Sjogren syndrome, and hypothyroidism presented to the emergency department with sudden severe dyspnea. Physical examination revealed a blood pressure of 130/80 mmHg and a heart rate of 120 bpm. The electrocardiogram showed sinus tachycardia. Pointof- care Ultrasound (US) documented a moderate bilateral pleural effusion, normal cardiac function, and a collapsible inferior vena cava. Compression US excluded lower extremity deep vein thrombosis. An arterial blood gas showed lactic acidosis (pH 7.31, lactates 36 mg/dL – normal value < 15) and a severe respiratory failure (PaO2/FiO2 ratio of 167). Enhanced Computed Tomography (CT) of the thorax was performed.