Why this topic matters: Thyroid storm is acute, life-threatening decompensation from severe thyrotoxicosis. It can cause extreme tachycardia, hyperthermia, agitation or coma, vomiting/diarrhoea, heart failure, atrial fibrillation, shock, liver injury and death. It is often precipitated by infection, trauma, surgery, labour, iodine exposure, diabetic ketoacidosis or stopping antithyroid treatment. Diagnosis is clinical; do not wait for thyroid results before resuscitation and specialist treatment.
Learning objectives
- Define thyroid storm and explain how excess thyroid hormone produces multi-organ decompensation.
- Recognise the clinical spectrum from untreated hyperthyroidism to storm, including atypical and apathetic presentations.
- Perform a rapid ABCDE assessment, severity score, focused history and precipitant search.
- Describe hospital treatment sequence: supportive care, beta-blockade, thionamide, iodine, glucocorticoid and cause control.
- Plan nursing monitoring, complication prevention, discharge education and special-population care.
Definition and pathophysiology
The thyroid produces thyroxine (T4) and triiodothyronine (T3), hormones that increase oxygen consumption, heat production, cardiac contractility, heart rate and sensitivity to catecholamines. Thyroid storm is not defined by a single hormone level; it is a clinical syndrome in which thyrotoxicosis is accompanied by fever and central nervous, cardiovascular, gastrointestinal/hepatic or other organ dysfunction.
Excess thyroid hormone accelerates metabolism and increases beta-adrenergic activity. A trigger such as infection or surgery increases catecholamines, cortisol demand and inflammatory stress. The result may be hyperthermia, dehydration, high-output heart failure progressing to cardiogenic shock, atrial fibrillation, delirium, hepatic dysfunction, lactic acidosis and multi-organ failure.
Causes and precipitating events
| Cause/trigger | Examples | Clues to search for |
|---|---|---|
| Underlying thyrotoxicosis | Graves disease, toxic multinodular goitre, toxic adenoma or thyroiditis. | Goitre, ophthalmopathy, tremor, weight loss, heat intolerance, palpitations. |
| Infection | Pneumonia, urinary infection, gastroenteritis, wound infection, malaria or sepsis. | Fever may be absent in older/immunosuppressed patients; look for subtle sources. |
| Medicine interruption | Stopped carbimazole/methimazole/PTU, poor access, vomiting or incorrect dose. | Medication history, empty packets and recent clinic interruption. |
| Physiological stress | Surgery, trauma, labour, myocardial infarction, stroke, DKA or pulmonary embolism. | Recent operation, delivery, chest pain, focal deficit, hyperglycaemia or hypoxia. |
| Iodine/drug exposure | Contrast, amiodarone, excess iodine, some biologic medicines. | Recent imaging, antiarrhythmic use or new specialist medication. |
Clinical features
- Thermoregulatory: high fever, hot sweaty skin, flushing, dehydration and heat intolerance.
- Cardiovascular: marked tachycardia, wide pulse pressure, atrial fibrillation, chest pain, high-output failure, pulmonary oedema, hypotension or shock.
- Neurological/psychiatric: anxiety, agitation, delirium, psychosis, confusion, lethargy, seizure or coma. Older adults may present with apathetic storm and little fever.
- Gastrointestinal/hepatic: nausea, vomiting, diarrhoea, abdominal pain, jaundice and acute liver dysfunction.
- Thyroid signs: goitre, bruit, tremor, hyperreflexia, lid retraction, ophthalmopathy and proximal weakness.
- Metabolic: hyperglycaemia, lactic acidosis, dehydration and electrolyte abnormalities.
Emergency red flags: temperature ≥38–39°C with altered mental state, heart rate ≥140/min, atrial fibrillation, pulmonary oedema, chest pain, hypotension, severe vomiting/diarrhoea, jaundice, seizure, coma or rapidly worsening weakness. Call for senior/critical-care help and transfer urgently.
First contact and scene management
- Use standard precautions; check the scene for collapse, vomit, medication containers and heat exposure.
- Activate emergency transport and senior clinical support. A suspected storm requires hospital-level monitoring, IV medicines and treatment of the precipitant.
- Move the patient to a cool, well-ventilated area, remove excess clothing and begin gentle cooling. Avoid shivering, ice immersion or vigorous rubbing.
- Ask relatives to bring antithyroid medicines, beta-blocker, recent results, diabetes medicines and details of infection, surgery, pregnancy or iodine exposure.
- Do not delay ABCDE, glucose and ECG for thyroid tests; do not give aspirin/salicylates to reduce fever because they may increase free thyroid hormone.
ABCDE assessment
A — Airway
- Assess speech, secretions, vomiting, agitation and consciousness. Delirium, fatigue or coma may compromise airway protection.
- Prepare suction and advanced airway support if the patient cannot protect the airway; involve anaesthesia/critical care early.
B — Breathing
- Count respiratory rate, assess effort and measure SpOâ‚‚. Look for pulmonary oedema, aspiration, pneumonia and metabolic acidosis.
- Give oxygen for hypoxaemia or respiratory distress according to local protocol; use non-invasive/invasive support with expert help if necessary.
C — Circulation
- Monitor pulse, BP, ECG, capillary refill, temperature, peripheral perfusion and urine output continuously in severe illness.
- Identify atrial fibrillation, narrow-complex tachycardia, ischaemia, high-output failure or shock. Obtain IV access and bloods.
- Give cautious isotonic fluid for dehydration, balancing pulmonary oedema and heart failure risk. If shock persists, involve critical care for vasoactive support.
D — Disability
- Record AVPU/GCS, pupils, agitation, delirium and seizure activity. Check bedside glucose to exclude hypoglycaemia or identify stress hyperglycaemia/DKA.
- Screen for stroke, intoxication, meningitis, heat stroke and other causes of altered consciousness.
E — Exposure
- Measure core temperature, inspect for goitre, ophthalmopathy, infection, surgical wounds and trauma.
- Maintain dignity while removing excess clothing, applying cooling measures and searching for infection or thromboembolism.
Focused history and examination
| Question/exam | What to establish | Why it matters |
|---|---|---|
| Thyroid history | Graves, goitre, thyroiditis, radioiodine, surgery, previous storm or recent abnormal results. | Identifies baseline risk and likely cause. |
| Medication adherence | Last carbimazole/methimazole/PTU, beta-blocker, amiodarone, steroids and missed doses. | Interruption is a common precipitant; amiodarone may cause thyroid dysfunction. |
| Trigger screen | Fever, cough, dysuria, diarrhoea, wounds, chest pain, trauma, surgery, labour, contrast, DKA or stroke symptoms. | Treating the precipitant is as important as controlling hormone effects. |
| Heart/lung exam | Pulse rhythm, JVP, crackles, oedema, murmurs, chest pain and signs of PE. | Guides cautious beta-blockade, fluids, diuresis and critical-care escalation. |
| Neuro/eye/neck | Agitation, delirium, tremor, hyperreflexia, goitre bruit, eye pain/visual change. | Assesses severity and identifies thyroid eye or pituitary/neurological differentials. |
Severity scoring and diagnosis
- The Burch–Wartofsky Point Scale considers temperature, tachycardia, gastrointestinal/hepatic dysfunction, central nervous system effects, heart failure and a precipitating event. A high score supports storm but does not replace clinical judgement.
- Japanese Thyroid Association criteria emphasise thyrotoxicosis plus fever, tachycardia, heart failure, gastrointestinal/hepatic symptoms and CNS disturbance.
- Thyroid storm is a clinical diagnosis. TSH is usually suppressed and free T4/free T3 elevated, but hormone levels overlap with uncomplicated thyrotoxicosis and results may be delayed.
- Do not withhold treatment while waiting for TSH, free T4 or free T3 when the patient has organ dysfunction and a compatible history.
Investigations
- Bedside glucose, continuous ECG, full blood count, electrolytes, urea/creatinine, magnesium, liver tests, CRP/lactate and venous/arterial blood gas when critically ill.
- TSH, free T4, free T3, thyroid antibodies when helpful; cortisol may be taken before steroids if this does not delay treatment.
- Blood/urine cultures, malaria testing where relevant, urinalysis, chest imaging, ECG/troponin, echocardiography and pregnancy test as indicated.
- Consider CT pulmonary angiography, brain imaging or abdominal imaging for pulmonary embolism, stroke, trauma, severe abdominal pain or liver pathology.
Immediate supportive treatment
- Admit to a monitored resuscitation, high-dependency or intensive-care environment according to severity.
- Control temperature with cooling blankets, tepid sponging, fans and paracetamol/acetaminophen if liver function and local protocol allow. Avoid salicylates.
- Correct dehydration carefully with isotonic crystalloid; treat hypoglycaemia, electrolyte disturbance and hypoxia promptly.
- Manage agitation safely with a calm low-stimulation environment and carefully titrated medication prescribed by the senior team; avoid excessive sedation that masks neurological deterioration.
- Start empiric antimicrobials promptly when infection is suspected after cultures where feasible; do not wait for thyroid results.
Specific hospital treatment sequence
| Order | Therapy | Purpose and cautions |
|---|---|---|
| 1. Beta-blockade | Propranolol or short-acting esmolol under specialist monitoring; diltiazem may be considered when beta-blockade is unsafe. | Controls adrenergic symptoms and tachycardia. Use extreme caution in shock, decompensated heart failure, severe asthma or cardiogenic pulmonary oedema. |
| 2. Thionamide | PTU or methimazole/carbimazole by oral, nasogastric or specialist-approved route. | Blocks new hormone synthesis; PTU also reduces T4-to-T3 conversion. Check liver injury/agranulocytosis risk and follow local dosing. |
| 3. Iodine | Potassium iodide/Lugol’s iodine after the thionamide, usually separated by at least one hour. | Blocks hormone release. Giving iodine before thionamide can provide substrate for new hormone synthesis. |
| 4. Glucocorticoid | Hydrocortisone or dexamethasone IV under the emergency protocol. | Supports possible relative adrenal insufficiency and reduces T4-to-T3 conversion; monitor glucose, infection and psychiatric effects. |
| 5. Treat the trigger | Antibiotics/source control, ACS/PE/stroke pathways, trauma care, DKA management or obstetric support. | Storm will not resolve if the precipitant is missed. |
Sequence matters: In hospital, thionamide is generally given before iodine. Exact drug, route and dose depend on age, pregnancy, liver function, heart failure, asthma and local protocol. EMTs should not independently initiate specialist antithyroid regimens without an authorised protocol and monitoring.
Cardiovascular and rhythm management
- Continuous ECG and frequent BP assessment are essential. Treat hypoxia, fever, dehydration and electrolyte abnormalities that worsen tachycardia.
- Atrial fibrillation may require rate control, anticoagulation assessment and cardiology input. Avoid reflexively giving a beta-blocker to a patient in shock or acute decompensated heart failure.
- Use diuretics for pulmonary oedema when prescribed; consider echocardiography, inotropes or vasopressors in cardiogenic shock with critical-care support.
- Cardioversion is reserved for selected unstable rhythms after senior review because recurrence is common while thyrotoxicosis persists.
Monitoring and nursing care
- Trend temperature, heart rate/rhythm, BP, respiratory rate, SpOâ‚‚, GCS/mental state, urine output and fluid balance closely.
- Repeat glucose, electrolytes, magnesium, liver function, lactate and blood gases according to severity and treatment.
- Maintain cooling, skin care, pressure-area care and safe hydration; avoid shivering and monitor for cold injury.
- Use fall, seizure, aspiration and delirium precautions. Keep the environment quiet and explain procedures repeatedly.
- Check every drug, timing and route; document antithyroid, beta-blocker, iodine and steroid administration and the response.
- Watch for thionamide adverse effects: rash, fever, sore throat/agranulocytosis, hepatitis and pancreatitis. Report new fever or throat pain urgently.
- Communicate trends during SBAR handover, including suspected trigger, highest temperature, heart rhythm, GCS, fluid balance and treatments.
Complications
- High-output heart failure progressing to pulmonary oedema, cardiogenic shock or cardiac arrest.
- Atrial fibrillation, ventricular dysrhythmia, myocardial ischaemia and thromboembolism.
- Hyperthermia, dehydration, acute kidney injury, lactic acidosis and electrolyte disturbance.
- Delirium, seizure, coma, aspiration and traumatic injury.
- Acute liver failure, jaundice, coagulopathy and hypoglycaemia.
- Medication harm: bronchospasm or shock from beta-blockade, liver toxicity from PTU, agranulocytosis from thionamides and hyperglycaemia/infection from steroids.
Special populations
- Pregnancy/labour: involve obstetrics and endocrinology; fetal tachycardia and maternal heart failure may occur. Radioiodine is contraindicated; drug choice and dose are specialist decisions.
- Heart failure/asthma: beta-blockers can cause collapse or bronchospasm; use a short-acting agent or alternative only with senior monitoring.
- Liver disease: PTU may worsen hepatic injury; monitor liver tests and obtain specialist advice.
- Older/apathetic patient: may have little fever or agitation but present with heart failure, delirium, weakness or collapse.
- Children: use paediatric weight-based protocols and specialist input; do not apply adult doses.
Clinical scenarios
Scenario 1 — Infection-triggered storm: A woman with Graves disease stopped carbimazole and now has fever 40°C, HR 155, agitation, vomiting and crackles. Start ABCDE, oxygen for hypoxaemia, ECG/IV access, cautious fluid assessment, cooling and urgent transfer. Prepare for infection treatment, beta-blockade only after senior review, thionamide, iodine after thionamide and hydrocortisone.
Scenario 2 — Storm with heart failure: An older man has tachyarrhythmia, pulmonary oedema and confusion but only a low-grade fever. Suspect apathetic storm. Sit upright, oxygen/ventilatory support, ECG, cautious fluids, urgent cardiology/ICU help and avoid a large beta-blocker bolus that could cause cardiovascular collapse.
Scenario 3 — Iodine exposure: A patient with untreated goitre deteriorates after contrast imaging with tremor, fever and rapid atrial fibrillation. Treat the clinical syndrome immediately, monitor rhythm and heart failure, investigate infection/ACS/PE and alert the endocrine team about recent iodine exposure.
Common errors to avoid
- Waiting for TSH, T3 or T4 results before treating a clinically unstable patient.
- Giving aspirin/salicylates for fever, or giving iodine before thionamide without a specialist reason.
- Using a large non-titrated beta-blocker dose in shock, severe asthma or decompensated heart failure.
- Missing infection, myocardial infarction, DKA, pulmonary embolism, stroke, labour or medicine interruption as the trigger.
- Assuming a quiet older patient cannot have storm because fever and agitation are absent.
STORM CARE: S — Support ABCDE and cooling; T — Tachycardia/temperature/trigger; O — Oxygen, glucose and ECG; R — Replace fluids cautiously; M — Medications in sequence; C — Control infection and complications; A — Avoid salicylates and unsafe beta-blockade; R — Reassess rhythm, GCS, urine and labs; E — Endocrine/critical-care escalation.
Revision questions
- How does thyroid hormone excess produce tachycardia, hyperthermia and heart failure?
- List six common precipitants of thyroid storm.
- Why is thyroid storm a clinical diagnosis rather than a laboratory number?
- State the usual sequence of beta-blocker, thionamide, iodine and glucocorticoid treatment.
- When can beta-blockade be dangerous, and what monitoring is required?
- Why should aspirin/salicylates be avoided for storm-related fever?
- Write an SBAR handover for Scenario 1.
Key takeaways
Thyroid storm is a clinical, multi-organ emergency. Resuscitate first, cool safely, monitor the heart, check glucose/electrolytes, find and treat the precipitant, and coordinate specialist treatment in the correct sequence without waiting for thyroid results.
References for further study
- Merck Manual Professional. Hyperthyroidism and Treatment of Thyroid Storm.
- NHS. Overactive thyroid: complications — emergency signs of thyroid storm.
- Society for Endocrinology. Clinical guidance and endocrine emergency resources.
- American Thyroid Association. Professional thyroid disease resources.
- Use current Uganda Ministry of Health, hospital, endocrine, cardiology and obstetric protocols for drug choice and dosing.