Thyroid Storm in Pregnancy — Inpatient Order Set (Example)

1. Location & Level of Care

• Admit to: ☐ ICU   ☐ Step-down / high-acuity OB unit
• Continuous telemetry and pulse oximetry.
• Nursing level of care: ☐ 1:1   ☐ 1:2 (per acuity).
• OB service: ☐ Primary team   ☐ Consulted
• Consults: ☐ Endocrinology   ☐ ICU/Critical care   ☐ Anesthesia   ☐ Cardiology (if decompensated heart failure/arrhythmia).

2. Diagnosis, Triggers & Initial Orders

• Working diagnosis: Thyroid storm in pregnancy (e.g., elevated free T4/T3, suppressed TSH, severe tachycardia, hyperthermia, CNS and/or GI–hepatic dysfunction).
• Document diagnostic scoring if used:
  • ☐ Burch–Wartofsky Point Scale (BWPS)
  • ☐ Institution-specific thyroid storm score
• Assess and document common precipitants:
  • ☐ Infection (urinary, respiratory, wound, chorioamnionitis)
  • ☐ Discontinuation or under-dosing of antithyroid medications
  • ☐ Surgery, trauma, labor, delivery, or postpartum hemorrhage
  • ☐ Iodinated contrast, preeclampsia, myocardial ischemia, or other stressors
• Vital signs at least every 15–30 minutes until stable, then hourly: HR, BP, RR, SpO₂, temperature.
• Continuous mental status and respiratory assessment; document changes promptly.
• Strict intake and output; hourly urine output in critically ill patients.

3. Labs & Diagnostic Studies

Serial Labs

• Electrolytes, renal function, and LFTs: q 12–24 hours initially, or more frequently if unstable.
• Thyroid function tests (free T4 ± T3): q 24–48 hours until improving, then spaced per endocrinology.
• CBC to monitor for agranulocytosis on antithyroid drugs.

4. Fluids, Electrolytes & Supportive Care

• IV access: ☐ 2 large-bore peripheral lines   ☐ Central line if needed
• Isotonic fluids (e.g., Lactated Ringer’s or normal saline) titrated to BP, urine output, and comorbidities (cardiac/renal).
• Strict input/output; consider Foley catheter if critically ill.
• Temperature management:
  • ☐ External cooling: cool packs, cooling blanket, tepid sponging.
  • ☐ Acetaminophen PRN for fever (avoid NSAIDs in 3rd trimester; avoid salicylates which may increase free thyroid hormone).
• Oxygen to keep saturation > 95% (or per maternal cardiac status).
• DVT prophylaxis unless contraindicated (mechanical ± pharmacologic per pregnancy protocol).

5. Beta-Blockade (First-Line: Propranolol or Esmolol)

Goal: control adrenergic symptoms (tachycardia, tremor) and modestly inhibit peripheral T4→T3 conversion. Use with caution in decompensated heart failure, severe asthma, or hemodynamic instability.

• Propranolol IV/PO (default):
  • Initial: Propranolol 0.5–1 mg IV over 10 minutes; may repeat every 5–10 minutes up to 2–3 mg total as tolerated to reduce HR (target HR often < 110–120/min, individualized by team).
  • Transition to oral: Propranolol 40–80 mg PO every 6 hours (or per cardiology/endocrinology guidance), adjust based on heart rate, BP, and symptoms.
• If IV beta-blocker contraindicated or poorly tolerated:
  • Consider esmolol infusion in ICU (short-acting) or other cardiology-directed regimen.
• Hold or reduce dose if hypotension, bradycardia, or signs of low output occur.
• Use caution to avoid prolonged fetal bradycardia; adjust dosing with MFM input.

6. Antithyroid Drug Therapy (PTU, then Consider Switch to MMI)

Many guidelines favor PTU for initial management of thyroid storm in pregnancy (due to partial inhibition of peripheral T4→T3 conversion), with transition to methimazole (MMI) when clinically stable and trimester-appropriate. Balance maternal hepatic risk and teratogenic concerns, and individualize decisions with endocrinology.

6A. Initial PTU Loading & Maintenance (Acute Storm)

• Propylthiouracil (PTU) loading dose:
  • PTU 500–1000 mg PO/NG as a single loading dose.
• PTU maintenance:
  • PTU 250 mg PO/NG every 4 hours (or 150–250 mg every 6 hours depending on institutional protocol and hepatic function).
• If unable to take PO/NG: consult pharmacy/endocrinology regarding rectal PTU formulation (if available) or alternative strategy.
• Baseline and serial LFTs and CBC to monitor for hepatotoxicity and agranulocytosis.

6B. Transition to Methimazole (MMI) Once Stable & Trimester-Appropriate

• When patient is clinically improved and beyond 1st trimester, or when hepatic toxicity risk from PTU is high:
  • Switch to Methimazole 20–30 mg PO every 8 hours initially, then titrate per free T4/T3 and clinical response.
• Avoid prolonged overlap of full high-dose PTU and MMI; coordinate with endocrinology.

IMPORTANT: Iodine (SSKI or Lugol’s solution) must be given at least 1 hour AFTER the first PTU dose to avoid fueling new hormone synthesis.

7. Iodine Therapy (After PTU)

• Confirm that PTU has been administered and documented.
• Start iodine ≥ 1 hour after PTU loading dose:
  • SSKI (saturated solution of potassium iodide):
    • 5 drops (≈250 mg iodine) PO/NG every 6 hours
  • OR Lugol’s solution:
    • 8–10 drops PO/NG every 6–8 hours
• Avoid starting iodine before antithyroid drug unless life-threatening circumstances and no access to antithyroid medication, in which case consult endocrine stat.
• Consider cholestyramine (e.g., 4 g PO/NG q6h) as an adjunct in severe cases per endocrinology.

8. Glucocorticoids (Block T4→T3 Conversion & Treat Possible Adrenal Insufficiency)

• Hydrocortisone (preferred):
  • Hydrocortisone 100 mg IV immediately, then 100 mg IV every 8 hours.
• Once clinically improving and enteral intake adequate, taper to physiologic dosing per endocrinology (e.g., hydrocortisone 20 mg AM / 10 mg PM) then taper off as appropriate.
• If hydrocortisone not available:
  • Dexamethasone 2 mg IV every 6 hours can be considered as alternative.

9. Treat Precipitating Cause

• Empiric broad-spectrum antibiotics if infection suspected, then narrow based on culture results and pregnancy-safe agents.
• Manage heart failure, arrhythmias, or myocardial ischemia in collaboration with cardiology and anesthesia.
• Optimize labor management or delivery planning with OB/MFM and anesthesia if storm occurs intrapartum or peripartum; generally avoid delivery during acute uncontrolled storm unless obstetric emergency.

10. Pregnancy-Specific & Fetal Monitoring

• Confirm gestational age and pregnancy status (singleton vs multiple gestation).
• Fetal assessment:
  • Pre-viable: intermittent Doppler FHR documentation.
  • Viable fetus (per institutional threshold): continuous electronic fetal monitoring when feasible and maternal condition allows.
• Monitor fetus for:
  • Tachycardia, late or prolonged decelerations, decreased variability.
  • Signs of possible fetal thyrotoxicosis (e.g., persistent fetal tachycardia, growth issues, hydrops in severe cases) in collaboration with MFM.
• Avoid over-beta-blockade that may cause sustained fetal bradycardia or growth restriction; titrate propranolol/esmolol carefully.
• Schedule MFM ultrasound (biometry, AFI, ± fetal goiter assessment) once maternal condition is stabilized.

11. Nutrition, GI & Symptom Management

• NPO initially if vomiting, altered mental status, or aspiration risk; advance diet as tolerated once stabilized.
• Antiemetics safe in pregnancy (e.g., ondansetron, metoclopramide) PRN.
• Bowel regimen as needed (e.g., stool softener) if opioids used.
• Analgesia and anxiolysis with pregnancy-appropriate medications as needed.

12. Ongoing Monitoring & Transition to Chronic Therapy

• Repeat labs every 24–48 hours initially:
  • Free T4, ± T3
  • Electrolytes, renal function
  • LFTs while on PTU/MMI and steroids
  • CBC for agranulocytosis surveillance
• Taper beta-blocker as HR and symptoms improve; avoid abrupt cessation.
• Once storm has resolved:
  • Transition to trimester-appropriate antithyroid regimen (e.g., PTU in 1st trimester, MMI in 2nd/3rd) with lowest effective dose.
  • Plan long-term management (definitive therapy usually deferred until postpartum in most cases).
• Provide anticipatory guidance for labor, delivery, and postpartum period (risk of recurrence, breastfeeding considerations on PTU/MMI, neonatal thyroid testing).
• Schedule follow-up with endocrinology and MFM prior to hospital discharge.

13. Discharge Planning

• Criteria for transfer from ICU to antepartum/OB ward:
  • Hemodynamically stable, no pressors, controlled HR and temperature, improving mental status, and reliable monitoring available.
• Provide written instructions on:
  • Daily dosing schedule of antithyroid medication and beta-blocker.
  • Warning symptoms (palpitations, fever, agitation, dyspnea, vomiting, jaundice).
  • When to seek emergency care.

References

1. Vadini V, Rizzo F, Colao A, et al. Thyroid storm in pregnancy: a review. J Endocrinol Invest. 2024. doi:10.1007/s40618-023-02273-1.
2. Burch HB, Wartofsky L. Life-threatening thyrotoxicosis. Thyroid storm. Endocrinol Metab Clin North Am. 1993;22(2):263–277.
3. Burch HB. The Point Scale for Thyroid Storm—32 Years and (Still) Counting. Thyroid. 2025. doi:10.1089/thy.2024.0659.
4. Alexander EK, Pearce EN, Brent GA, et al. 2017 Guidelines of the American Thyroid Association for the Diagnosis and Management of Thyroid Disease During Pregnancy and the Postpartum. Thyroid. 2017;27(3):315–389.
5. ACOG Practice Bulletin No. 223. Thyroid Disease in Pregnancy. Obstet Gynecol. 2020;135(6):e261–e274.
6. De Almeida R, et al. Clinical review and update on the management of thyroid disease in pregnancy. Arch Endocrinol Metab. 2022;66(4):479–493.
7. Farooqi S, Bianco AC. Thyroid storm. Endocrinol Metab Clin North Am. 2022;51(2):355–371.
8. Lee SY, Yu HW, Kim SJ, et al. Propylthiouracil vs Methimazole for Treatment of Thyroid Storm: A Multicenter Cohort Study. JAMA Netw Open. 2023;6(4):e2310400.
9. Pearce EN. A comparison of ATA and updated ACOG guidelines for management of thyroid disease in pregnancy. Clin Thyroidol. 2020;32(7):317–320.

Disclaimer

This OBPharm order set is an educational template intended for instructional purposes only. It is not intended to replace institutional protocols or consultation with endocrinology, maternal–fetal medicine, anesthesia, and critical care.

Doses and strategies should always be verified against current references, local guidelines, and patient-specific factors (e.g., renal/hepatic function, gestational age, co-morbid conditions, and fetal status). For EHR implementation (e.g., Cerner), each bullet should be mapped to local orderables and adjusted to match system-specific naming, dosing defaults, and routing.