Emergency Medicine · Year 3 · from Emergency Medicine

Case 2: Thyroid Storm - The Agitated Hyperthyroid Patient

Patient Demographics

• Age: 38 years
• Sex: Female
• Occupation: Marketing executive

Chief Complaint

"She's acting crazy and won't stop sweating."

History of Present Illness

Husband brings 38-year-old wife for evaluation of progressive agitation, tremor, and profuse sweating over the past 3 days. She has known Graves' disease diagnosed 6 months ago but stopped taking her methimazole 3 weeks ago "because she felt fine." Two days ago she developed an upper respiratory infection with fever. Today she became confused, extremely agitated, and her husband is worried she is "going to have a heart attack."

Initial Assessment

ESI Level: 1 - Life-threatening endocrine emergency

First Impression:

• Appearance: Extremely agitated, restless, diaphoretic
• Work of breathing: Tachypneic
• Circulation: Flushed, visibly bounding pulses

Vital Signs:

• Heart rate: 168 bpm, irregularly irregular
• Blood pressure: 162/54 mmHg (widened pulse pressure)
• Respiratory rate: 28 breaths/min
• SpO2: 96% on room air
• Temperature: 40.2C (104.4F)
• GCS: 13 (E4V4M5 - confused, agitated)

Thyroid Storm - Clinical Recognition

Burch-Wartofsky Point Scale (>45 suggests thyroid storm):

Total Score: 100 (thyroid storm very likely)

Primary Survey

Airway: Patent, speaking (rapid, pressured speech) Breathing: Tachypneic, clear lungs Circulation: Tachycardic (atrial fibrillation with RVR), hyperdynamic Disability: Agitated, confused, moving all extremities Exposure: Profuse diaphoresis, tremor, no goiter visible (check for proptosis)

Physical Examination

Thyroid-Specific Findings:

• Eyes: Lid lag, proptosis (Graves' ophthalmopathy)
• Neck: Diffusely enlarged thyroid gland, bruit over thyroid
• Cardiac: Irregular, tachycardic, hyperdynamic precordium
• Skin: Warm, moist, pretibial myxedema present
• Neuro: Fine tremor, hyperreflexia, agitation
• Extremities: Proximal muscle weakness

Secondary Survey

SAMPLE History:

• Symptoms: Agitation, sweating, tremor, palpitations, confusion
• Allergies: None
• Medications: Methimazole (stopped 3 weeks ago)
• PMH: Graves' disease, anxiety
• Last Meal: Yesterday (poor appetite)
• Events: URI symptoms x2 days, progressive symptoms

Precipitants of Thyroid Storm:

• Infection (this patient - URI)
• Medication non-compliance (this patient - stopped methimazole)
• Surgery, trauma, iodine load, pregnancy

Diagnostic Testing

Labs:

• TSH: <0.01 mIU/L (suppressed)
• Free T4: 8.2 ng/dL (markedly elevated; normal 0.8-1.8)
• Free T3: 18.4 pg/mL (elevated; normal 2.3-4.2)
• CBC: WBC 12.8 (infection)
• BMP: K 3.2, glucose 142
• LFTs: AST 88, ALT 76 (mild elevation)
• Cortisol: Ordered (check for adrenal insufficiency)

ECG: Atrial fibrillation with RVR, rate 168

Chest X-ray: Mild cardiomegaly, no infiltrates

Diagnosis

Thyroid Storm secondary to:

1. Medication non-compliance (methimazole)
2. Precipitated by upper respiratory infection

Management - Multi-Pronged Approach

1. Block Hormone Synthesis (Thionamide):

• Propylthiouracil (PTU) 200mg PO/NG q4h (preferred over methimazole in storm - also blocks peripheral T4→T3 conversion)

2. Block Hormone Release (Iodine - give AFTER thionamide):

• SSKI 5 drops PO q6h OR Lugol's solution (started 1 hour after PTU)
• Must give thionamide first or iodine will increase hormone synthesis

3. Block Peripheral Effects (Beta-blocker):

• Propranolol 60-80mg PO q4-6h OR Esmolol drip
• Controls heart rate and blocks peripheral T4→T3 conversion

4. Block Peripheral Conversion (Corticosteroid):

• Hydrocortisone 100mg IV q8h
• Blocks T4→T3 conversion
• Prevents relative adrenal insufficiency

5. Supportive Care:

• Aggressive cooling (external cooling, acetaminophen)
• IV fluids (high output state)
• Glucose supplementation
• Treat underlying precipitant (antibiotics if bacterial infection)

6. Rate Control (Atrial Fibrillation):

• Beta-blocker (propranolol)
• Consider digoxin if hypotensive (thyroid storm patients may need higher doses)

Treatment Summary

Clinical Course

At 6 hours:

• Temperature: 38.8C (cooling measures)
• HR: 118 (beta-blocker effect)
• Less agitated, following commands

At 24 hours:

• Temperature: 37.4C
• HR: 92, converted to sinus rhythm
• Alert, oriented, cooperative

At 48 hours:

• Stable, free T4 trending down
• Transitioned to oral medications
• Thyroid levels: Free T4 4.2 ng/dL (improving)

Disposition

• ICU admission for first 48 hours
• Step-down for 24 hours
• Endocrinology consultation
• Discharged day 4 on methimazole with close follow-up
• Educated extensively on medication compliance
• Discussed definitive treatment options (radioactive iodine, surgery)

Teaching Points

1. Thyroid storm is clinical diagnosis: Don't wait for labs; treat based on Burch-Wartofsky score
2. Multi-drug approach essential: Target synthesis, release, peripheral conversion, and effects
3. Order matters: Give thionamide BEFORE iodine
4. Avoid aspirin: Displaces thyroid hormone from binding proteins, increasing free hormone
5. Beta-blockers do double duty: Control symptoms AND block peripheral T4→T3 conversion (propranolol)
6. Steroids for everyone: Blocks conversion and prevents adrenal crisis
7. Identify precipitant: Infection, non-compliance, surgery - treat underlying cause
8. Atrial fibrillation common: Usually converts with treatment of underlying storm

Clinical Image

Image Description: Photograph demonstrating bilateral exophthalmos (proptosis) in a patient with Graves' disease, showing characteristic lid retraction and scleral show above and below the iris.

Attribution: Image from Wikimedia Commons, Graves' disease exophthalmos. Licensed under CC BY-SA 3.0. Source: https://commons.wikimedia.org/wiki/File:Proptosis_and_lid_retraction_from_Graves%27_Disease.jpg

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