Bedside point-of-care ultrasound in the early recognition of thyrotoxic crisis: a case report

Thyroid storm is the life-threatening extreme of decompensated thyrotoxicosis, and its earlier phase, thyrotoxic crisis with impending storm, is equally important to recognise. The diagnosis is clinical and supported by biochemical hyperthyroidism, but confirmatory thyroid function tests are often unavailable during the initial emergency department (ED) evaluation, and the presentation overlaps with sepsis, arrhythmia, and acute coronary syndrome. A 56-year-old woman presented with two weeks of palpitations and one week of exertional dyspnea, anorexia, and diarrhea. She was tachycardic (154 beats/min) with pretibial myxedema. Point-of-care ultrasound (POCUS) showed a hyperdynamic left ventricle with a markedly increased left ventricular outflow tract velocity-time integral (33.7 cm at 115 beats/min) and diffusely increased thyroid vascularity (‘thyroid inferno’) on color Doppler. A thyrotoxic crisis (impending thyroid storm) was recognised and treatment was started in the ED on the basis of the clinical and sonographic findings; thyroid function tests reported 35 min after the thyroid scan confirmed severe hyperthyroidism (free T4 5.95 ng/dL, TSH < 0.03 uIU/mL). The patient recovered. Integrated cardiac and thyroid POCUS can provide an immediate bedside clue to thyrotoxicosis before laboratory confirmation, helping to corroborate clinical suspicion and expedite recognition of a potentially life-threatening emergency.