Thyroid Emergencies: A Narrative Review

Abstract

Introduction: Myxedema coma and thyroid storm are rare thyroid emergencies associated with considerable mortality and morbidity.

Results: Myxedema coma is a state of decompensated hypothyroidism with widespread multi-organ dysfunction, including impaired consciousness, mixed respiratory failure, and hypothermia. Thyroid storm is the extreme state of thyrotoxicosis occurring when a patient's metabolic, thermoregulatory, and cardiovascular compensatory mechanisms are surpassed; clinical features include hyperthermia, neuropsychiatric symptoms, and tachyarrhythmias. Thyroid emergencies usually result from a precipitating event or trigger transforming a previously compensated hypothyroid or thyrotoxic state. Supportive care for the cardiovascular, respiratory, and thermoregulatory manifestations, as well as possible intercurrent illness or adrenal insufficiency, plays a lead role in the management. For myxedema coma, treatment typically includes high-dose levothyroxine with the addition of liothyronine for critically ill patients. Management of thyroid storm is multipronged and stepwise, consisting of first-line thionamide and beta-adrenergic receptor antagonist therapy, followed by inorganic iodine, cholestyramine, plasmapheresis, or emergent thyroidectomy in appropriate severely ill patients.

Conclusions: This review provides an updated narrative overview of the diagnosis and management of myxedema coma and thyroid storm.

Keywords: hypothyroidism; myxedema coma; thyroid emergencies; thyroid storm; thyrotoxicosis.