What is the treatment for thyroid storm?

Treatment of Thyroid Storm

Thyroid storm requires immediate multi-drug therapy without waiting for laboratory confirmation: start propylthiouracil (or methimazole), followed 1-2 hours later by potassium iodide, plus beta-blockers and corticosteroids, along with aggressive supportive care to prevent mortality. 1, 2

Immediate Stabilization and Hospitalization

• All patients with thyroid storm require hospitalization, with severe cases mandating ICU admission. 1, 2
• Provide supplemental oxygen and position the patient head-up to improve respiratory function. 2
• Establish large-bore IV access for fluid resuscitation and medication administration. 3
• Do not delay treatment while awaiting thyroid function tests—mortality rises significantly with treatment delays. 2

Multi-Drug Treatment Algorithm

Step 1: Block Thyroid Hormone Synthesis (Start Immediately)

• Propylthiouracil (PTU) is the preferred first-line agent because it inhibits both thyroid hormone synthesis AND peripheral conversion of T4 to T3. 1, 2, 4
• Methimazole is an acceptable alternative if PTU is unavailable, though it lacks the peripheral conversion blocking effect. 5, 1
• PTU does not inactivate existing circulating thyroid hormone, so additional therapies are essential. 4

Step 2: Block Thyroid Hormone Release (1-2 Hours After Thionamides)

• Administer saturated potassium iodide solution (SSKI) or sodium iodide 1-2 hours AFTER starting thionamides. 1, 2
• Critical pitfall: Never give iodine before thionamides—this can paradoxically worsen thyrotoxicosis by providing substrate for new hormone synthesis. 1, 3
• Alternative agents include Lugol's solution or lithium if iodine is contraindicated. 5

Step 3: Control Adrenergic Symptoms with Beta-Blockers

• Propranolol is the preferred beta-blocker at 60-80 mg orally every 4-6 hours, as it also blocks peripheral T4 to T3 conversion. 1, 3, 6
• For hemodynamically unstable patients or those on vasopressor support, use esmolol due to its ultra-short half-life allowing rapid titration. 1, 7
  • Esmolol loading dose: 500 mcg/kg (0.5 mg/kg) IV over 1 minute 1
  • Maintenance infusion: Start at 50 mcg/kg/min, titrate up to maximum 300 mcg/kg/min 1
  • Monitor continuously for hypotension, bradycardia, and hyperkalemia (especially with renal impairment) 1, 7
• If beta-blockers are contraindicated (severe heart failure, bronchospasm), use non-dihydropyridine calcium channel blockers like diltiazem 15-20 mg (0.25 mg/kg) IV over 2 minutes, then 5-15 mg/h maintenance. 5, 1
• High doses of beta-blockers may be required in thyroid storm due to the hypermetabolic state. 5

Step 4: Reduce Peripheral T4 to T3 Conversion

• Administer dexamethasone or another corticosteroid to block peripheral conversion of T4 to T3 and treat potential relative adrenal insufficiency. 5, 1, 2

Essential Supportive Care

• Treat fever aggressively with antipyretics (avoid aspirin as it may displace thyroid hormone from binding proteins). 5, 1
• Provide cooling measures for hyperthermia. 8
• Identify and treat the precipitating trigger (infection, surgery, trauma, labor/delivery, medication non-compliance). 5, 8, 9
• Manage agitation with sedatives as needed. 8
• Provide aggressive hydration and electrolyte replacement. 8

Critical Monitoring Requirements

• Continuous cardiac monitoring with serial blood pressure and heart rate every 5-15 minutes during beta-blocker titration. 1
• Monitor for cardiac complications including heart failure, arrhythmias, and cardiovascular collapse. 5, 2, 3
• Watch for agranulocytosis with thionamide use—if sore throat and fever develop, obtain CBC immediately and discontinue the thionamide. 5, 2
• Monitor for other thionamide side effects: hepatitis, vasculitis, thrombocytopenia. 5
• Check coagulation parameters if coagulopathy is suspected. 3

Special Populations

Pregnancy

• The treatment protocol is identical to non-pregnant patients. 5, 2, 3
• Monitor fetal status with ultrasound, nonstress testing, or biophysical profile depending on gestational age. 5
• Avoid delivery during thyroid storm unless absolutely necessary—maternal heart failure risk is extremely high. 5, 2
• Fetal thyroid suppression from thionamides is usually transient and rarely requires treatment. 5

Refractory Cases

• For patients not responding to conventional therapy, consider therapeutic plasma exchange to rapidly remove circulating thyroid hormone. 10
• Alternative adjunctive therapies include cholestyramine (to interrupt enterohepatic circulation), lithium carbonate, or potassium perchlorate. 11, 8

Post-Acute Management

• Monitor thyroid function every 2-3 weeks after initial stabilization. 1, 2, 3
• Watch for transition to hypothyroidism, which commonly occurs after thyroid storm treatment and may require levothyroxine replacement. 1, 2
• Adjust beta-blocker doses as the patient becomes euthyroid due to increased drug clearance during hyperthyroidism. 2
• Plan definitive treatment (continued medical therapy, thyroidectomy, or radioactive iodine ablation) after the acute crisis resolves. 2, 12

Key Pitfalls to Avoid

• Never administer iodine before thionamides—this is the most critical error that can worsen the crisis. 1, 3
• Do not abruptly discontinue beta-blockers—this may precipitate thyroid storm exacerbation or cardiovascular complications. 6, 7
• Do not use radioactive iodine during acute thyroid storm or in pregnancy. 5
• Beta-blockers may mask clinical signs of hyperthyroidism, making assessment difficult. 6, 7
• In patients with Wolff-Parkinson-White syndrome, beta-blockade can cause severe bradycardia requiring pacemaker placement. 6