Weekly Report – Thyroid Storm

Presentation:  50 yo F with PMH of hypertension presents for shortness of breath and altered mental status. The patient is lethargic in obvious respiratory distress. Her BP is 230/130, HR is 170, RR is 35, O2 is 90% on NRB, and Temp is 38.1. She has crackles throughout all lung fields. She is intubated for respiratory failure on arrival. Postintubation a significant goiter is noted.

• Thyroid storm is a rare endocrinologic emergency that carries a high mortality if unrecognized. Symptoms are those of extreme hyperthyroidism, including hyperthermia, tachycardia, tremors, heart failure, GI symptoms, and neurologic symptoms. Patients typically have a history of hyperthyroidism (which may be previously undiagnosed) which is exacerbated by a stressor, such as infection, trauma, surgery, MI, or an iodine load (ie iodinated contrast or amiodarone).

• Diagnosis is made by clinical criteria and clinical suspicion. A high level of clinical suspicion should be held in patients with thyrotoxicosis and evidence of systemic decompensation, typically respiratory failure or significant alterations of mental status. Scoring criteria have been developed to guide diagnosis:

Recommended treatment has four components:

• Beta Blockade
  • Propranolol
    • 60-80 mg q4hr PO or via NG tube
    • 1 mg IV q15min to effect
    • Inhibits T4 to T3 conversion
  • Esmolol
    • Easily titratable to effect in critically ill patients
• Thionamide
  • Methimazole
    • 60-80 mg/day PO or via NG tube
    • Preferred by most endocrinologist as is less hepatotoxic than PTU
  • Propylthiouracil
    • 500-1000 mg load, then 250 mg q4hr PO or via NG tube
    • Inhibits T4 to T3 conversion
    • Preferred during pregnancy as methimazole is teratogenic
• Iodine
  • Saturated Solution of Potassium Iodide (SSKI) 5 drops orally q6hr
  • Administer 1 hour after thionamide so as not to exacerbate storm
• Hydrocortisone
  • 300 mg IV loading dose, then 100 mg q8hr IV

Case Conclusion: TSH returned undetectable while T4 and T3 were markedly elevated. She was started on methimazole, SSKI, Hydrocortisone and Esmolol GGT with improvement in vital signs. Antibiotics were given for likely pneumonia as precipitating factor. She was weaned from the vent and went home 2 weeks later with a new diagnosis of hyperthyroidism and plans for further outpatient workup and treatment.