Thyroid Storm
Ben French
Presentation
- Exaggerated signs/symptoms of thyrotoxicosis causing multi-organ dysfunction in the presence of a precipitating insult.
- Common precipitants: amiodarone, Graves’ disease, surgery (especially thyroid surgery), pregnancy, infection, MI, PE, medication non-compliance, iodine loads.
- Common presenting symptoms: tachycardia/arrythmia, new CHF, AMS, hyperthermia, diaphoresis, GI upset, new jaundice.
- If concerned for thyroid storm, use the Burch-Wartofsky Point Scale (BWPS), available on MDCalc.
- >45 is highly suggestive
- 25-44 impending thyroid storm
- <25 unlikely to represent thyroid storm.
- NOTE: the degree of free thyroid hormone elevation has not been shown to correlate with the incidence of thyroid storm.
Management
- ENDOCRINE EMERGENCY – ASAP consult to Endocrinology.
- Treatment of underlying precipitant
- Supportive care including cooling blankets, vasopressors, and intubation if indicated.
- Decrease T4 to T3 conversion (give both medications):
- PO propranolol 60-80mg every 4 hours (avoid in acute CHF, avoid in shock).
- IV hydrocortisone 300mg load, followed by 100mg every 8 hours.
- Block thyroid hormone synthesis and secretion (PTU or MMI, plus Lugol’s):
- PTU: 500-1000mg loading dose, followed by 250mg every 4 hours (PO, rectal).
- Methimazole: 20mg every 4-6 hours (PO, rectal).
- Decrease T4 to T3 conversion (give both medications):
- Lugol’s solution 8 drops (0.4ml) every 6 hours, starting at least one hour after initiation of PTU or methimazole. (Lugol’s is an iodine-containing solution. Iodine suppresses thyroid hormone release via the Wolff-Chaikoff effect.)
- Refractory storm: plasmapheresis and plasma exchange.
After recovery, patients should be recommended for definitive treatment with radioactive iodine therapy or thyroidectomy.
