Thyroid Storm

Thyroid storm is a sudden, life-threatening exacerbation of thyrotoxicosis. Some series suggest a mortality rate of between 30 and 75%. 
Its manifestations are due to the action of excess thyroid hormone. 
Fever is the most characteristic feature, with the temperature often rising above 41°C. There may be evidence of organ damage. 
The clinical picture is frequently clouded by a secondary infection such as pneumonia or a viral infection. 
Death may be caused by cardiac arrhythmia, congestive heart failure, hyperthermia or other unidentified factors. 
The diagnosis of thyroid storm is made entirely on clinical grounds. The results of thyroid function tests will rarely be available soon enough to make the diagnosis. 
Propylthiouracil followed by a stable iodine preparation (eg Lugol’s iodine) is usually given. 
Propranolol, intravenous fluids, dexamethasone and cooling are also often required. Finally, one must remember to treat the precipitating cause.