Makindo Medical Notes

Related Subjects: |Thyrotoxicosis and Hyperthyroidism |Thyroid Storm - Thyrotoxic crisis |Graves Disease (Thyrotoxicosis) |Amiodarone and Thyroid disease |Thyroid Surgery (Thyroidectomy) |Hypothyroidism |Hashimoto's thyroiditis |DeQuervain's thyroiditis |Subacute Thyroiditis |Thyroid nodule |Congenital Hypothyroidism |Thyroid Function Tests and antibodies |Post partum thyroiditis |Sick Euthyroid Syndrome |Thyroid Exam (OSCE) |Thyroid Gland anatomy and Physiology |Thyroid Cancer

⚡ Thyroid storm is a rare, life-threatening endocrine emergency caused by excess thyroid hormone activity. Mortality remains high despite treatment (10–20%). ⚠️ Avoid aspirin as an antipyretic — it displaces thyroxine from binding proteins, worsening the crisis.

📖 About

• 🧾 First described in 1926.
• 🌡️ Life-threatening escalation of thyrotoxicosis, usually triggered by stress or illness.
• Occurs in ~2% of hyperthyroid patients, often on a background of untreated or undertreated Graves’ disease.

🧬 Aetiology

• Graves’ disease (most common).
• Multinodular goitre or thyroiditis.
• Post-thyroidectomy in patients still thyrotoxic.

🔥 Precipitants

• Intercurrent illness: infection, myocardial infarction, diabetic ketoacidosis.
• Radioiodine therapy or abrupt withdrawal of antithyroid drugs.
• Surgery, trauma, or childbirth.
• Certain immunotherapies (e.g. IL-2, interferon-α).

🩺 Clinical Features

• 🚑 Hyperadrenergic state: tachycardia, atrial fibrillation, sweating, pyrexia >40 °C.
• 💡 Neuropsychiatric: agitation, delirium (hypo/hyperactive), psychosis, seizures.
• ⚡ Cardiovascular: palpitations, high-output heart failure, shock.
• 🩸 GI/hepatic: abdominal pain (mimicking acute abdomen), jaundice.
• 👀 Eye signs and goitre suggest underlying Graves’ disease.
• NB: In the elderly, may be “apathetic” with lethargy, rather than agitation.

🔍 Differentials

• Septic shock or systemic infection.
• Other causes of delirium (delirium tremens, anticholinergic toxicity).
• Acute pulmonary oedema or cardiogenic shock.

🧪 Investigations

• 🧾 Bloods: FBC, U&E, Ca, LFTs, ESR/CRP.
• 📈 Thyroid panel: T3/T4 (raised), TSH (suppressed) — confirms diagnosis retrospectively.
• 📊 ECG for arrhythmias (often AF).
• 📸 CXR if pneumonia suspected.
• Thyroid autoantibodies for underlying cause.

🛠️ “The 5 Bs” Treatment Principles

• 🔒 Block hormone synthesis → Carbimazole, Propylthiouracil (PTU).
• 🚫 Block hormone release → Potassium iodide (given 1 hr after antithyroid drugs).
• ⏸️ Block T4→T3 conversion → PTU, propranolol, corticosteroids, amiodarone (rarely).
• 💓 Beta-blockade → Propranolol (rate control, symptom relief).
• 🌀 Block enterohepatic circulation → Cholestyramine.

💊 Management

• ABC resuscitation, ITU/HDU involvement, oxygen, IV access, cooling measures.
• IV fluids: start with 1L 0.9% NaCl over 2–4 hrs; correct electrolytes.
• Antipyresis: IV paracetamol (avoid aspirin).
• Sedation for agitation: Chlorpromazine (also reduces temperature) or Diazepam.
• Antithyroid therapy:
  • PTU 200 mg PO/NG, then 250 mg q6h (preferred, as it reduces T4→T3).
  • Carbimazole 20 mg q6h if PTU unavailable.
• Potassium iodide 0.3 ml PO TDS (1 hr after antithyroid drug).
• Steroids: Dexamethasone 2 mg q6h or Hydrocortisone 100 mg q8h (reduces T4→T3 and dampens autoimmune process).
• Adjuncts: Pabrinex if malnourished; Plasmapheresis in refractory cases.

⚠️ Complications

• Life-threatening shock (exclude cardiomyopathy, treat sepsis).
• DIC and multi-organ failure.
• Congestive cardiac failure (may require diuretics, nitrates, digoxin, CPAP).
• Status epilepticus (diazepam, phenytoin/fosphenytoin).

📚 References

• Endocrine and metabolic emergencies: Thyroid storm (NIH)
• 2016 Japan Thyroid Association Guidelines for Thyroid Storm