AKA Hyperthyroid Crisis or Thyroid storm

Presents as a life threatening exacerbation of Hyperthyroidism.Despite early recognition and treatement, mortality is still 10 % and upto 30% when presents with Hyperthermia, Cardiac failure and arrhythmia.

Precipitating Factors of Thyrotoxic Crisis-

1. Acute illness (e.g. stroke, infection, trauma, Diabetic Ketoacidosis or DKA)
2. Surgery (especially subtotal thyroidectomy when patient is ill-prepared)
3. Radioiodine treatment of a patient with partially treated or untreated hyperthyroidism.

Presentations-

• Fever
• Delirium
• Seizures
• Coma
• Diarrhea
• Jaundice
• Hyperthermia
• Agitation
• Confusion
• Tachycardia
• Vomiting
• Atrial fibrillation
• Heart Failure

Management-

Management requires ICU monitoring , Identification and treatment of the precipitating cause, and measures that reduce thyroid hormone synthesis

1. Rehydation , cooling, and oxygen.
2. Broad-Spectrum Antibiotics to prevent infection
3. Large doses  Propylthiouracil (600 mg loading dose followed by 200–300 mg every 6 hrly)  given  orally or by nasogastric tube or per rectum; the drug’s inhibitory action on T₄ to T₃ conversion makes it the antithyroid drug of choice. 1 hour after the 1st dose of propylthiouracil, stable iodide is given . It blocks T3T4 synthesis via the Wolff-Chaikoff effect (the delay allows the antithyroid drug to prevent the excess iodine from being incorporated into new hormone).( Harrison’s Principle of Internal Medicine)
4. Propanolol- rapidly at 80mg 6 hrly oral or IV 1-5mg 6 hrly. reduce tachycardia and other adrenergic manifestations. high doses of propranolol decrease T₄ to T₃ conversion
5. Carbimazole- useful in incooperative patients. Can be used per rectally at 40-60mg daily.
6. Sodium Iopodate 500mg per day orally. It restores T3 levels to normal in 48-72 hours and reduces peripheral conversion of T4 to T3 which is active form.\
7. Potassium Iodide or Lugol’s Iodine- Not preferred now.
8. Dexamethasone- 2 mg 6 hrly
9. Amiodarone.??  Also Read about Hypothyoidism

A case Study- Case

Article by Dr. Sujit Shrestha ( References- Harrison’s Principle of Int. Med., Davidsons Principle and Practice of Med., Online sources)

Tags: thyroid storm, thyrotoxicosis

Last updated: April 5, 2011

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• » Hypothyroidism : Clinical featues, diagnosis and treatment