Thyroid Nursing Guide 2026
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Hyperthyroidism to thyroid storm, hypothyroidism to myxedema coma — comprehensive nursing assessment, pharmacology, and life-threatening emergency management.
1. Thyroid Hormone Basics
The thyroid produces T4 (thyroxine — storage form) and T3 (triiodothyronine — active form). T4 is converted to T3 in peripheral tissues. TSH (thyroid-stimulating hormone) from the pituitary regulates production via negative feedback.
Key lab values:
- TSH: 0.4–4.0 mU/L (most sensitive thyroid test)
- Free T4 (FT4): 0.8–1.8 ng/dL
- Free T3 (FT3): 2.3–4.2 pg/mL
- Interpretation rule: Low TSH + High T4/T3 = Hyperthyroidism | High TSH + Low T4 = Hypothyroidism | High TSH + Normal T4 = Subclinical hypothyroidism
2. Hyperthyroidism
Causes
| Cause | Notes |
|---|
| Graves' disease (most common) | Autoimmune — TSI antibodies stimulate TSH receptor; hallmark: diffuse goiter + exophthalmos (proptosis) + pretibial myxedema (dermopathy) |
| Toxic multinodular goiter | Multiple autonomous nodules; more common in elderly |
| Toxic adenoma (Plummer's disease) | Single hot nodule — solitary autonomous nodule |
| Subacute thyroiditis | Painful, post-viral; transient hyperthyroidism then hypothyroidism then normal |
| Amiodarone-induced | Amiodarone is 37% iodine by weight; can cause both hyper and hypothyroidism |
| Exogenous thyroid hormone excess | Over-replacement or factitious |
Signs & Symptoms of Hyperthyroidism
Think: Everything is FAST and HOT
- Cardiovascular: Tachycardia, palpitations, atrial fibrillation, widened pulse pressure, hypertension, heart failure
- Metabolic: Heat intolerance, increased sweating, weight loss despite increased appetite, hyperthermia
- Neurologic: Anxiety, nervousness, emotional lability, insomnia, tremor (fine tremor of outstretched hands), hyperreflexia
- GI: Hyperdefecation or diarrhea, nausea
- Musculoskeletal: Weakness, fatigue, proximal muscle weakness
- Eye (Graves' specific): Exophthalmos (proptosis), lid lag, lid retraction, diplopia — protect eyes with lubricating drops
- Skin: Warm, moist, flushed; fine hair; Graves' dermopathy (pretibial)
Treatment
| Treatment | Mechanism | Notes |
|---|
| Propylthiouracil (PTU) | Blocks thyroid hormone synthesis + blocks T4→T3 conversion | Preferred in 1st trimester pregnancy and thyroid storm. Monitor: agranulocytosis (CBC), hepatotoxicity (LFTs) |
| Methimazole | Blocks thyroid hormone synthesis (does NOT block T4→T3) | Preferred for most adults; teratogenic in 1st trimester (choanal atresia, aplasia cutis). Monitor: agranulocytosis |
| Beta-blockers (propranolol most common) | Block sympathomimetic effects; propranolol also blocks T4→T3 | Immediate symptom relief while waiting for thionamides to work; use for HR, tremor, anxiety, sweating |
| Radioactive iodine (RAI/I-131) | Destroys thyroid tissue | Definitive treatment in non-pregnant adults; takes 6–12 weeks for full effect; avoid pregnancy 6 months after; worsens Graves' ophthalmopathy transiently |
| Thyroidectomy | Remove thyroid | Indicated in large goiter, failed medical therapy, pregnancy (2nd trimester), suspected malignancy. Post-op: watch for hypocalcemia, recurrent laryngeal nerve injury |
3. Thyroid Storm (Thyrotoxic Crisis)
Life-threatening exacerbation of hyperthyroidism. Precipitants: infection, surgery, trauma, MI, radioactive iodine, iodine contrast dye, abrupt discontinuation of antithyroid medications, childbirth.
Burch-Wartofsky Score (Thyroid Storm Diagnosis)
Scores thermoregulatory dysfunction (temp), CNS effects, GI dysfunction, cardiovascular effects (HR, A-Fib, heart failure). Score ≥45 = thyroid storm; 25–44 = impending storm.
Clinical Features
Thyroid Storm Triad:
- Hyperpyrexia: Temp >38.5°C (often >40°C/104°F) — NOT explained by other causes
- Cardiovascular: HR >140, A-Fib, heart failure, shock
- CNS: Agitation, delirium, psychosis → stupor → coma
- GI: N/V/D, jaundice (hepatic failure), abdominal pain
Thyroid Storm Treatment — Specific Order Matters!
Give in this order (mnemonic: BBIIPS or "Block Block Block Treat Treat"):
- Beta-blocker FIRST — Propranolol 60–80 mg PO q4h or 0.5–1 mg IV (also blocks T4→T3). Esmolol if IV needed. Controls heart rate and sympathomimetic symptoms immediately.
- PTU (not methimazole) — 500–1000 mg PO loading, then 250 mg q4h. Blocks new hormone synthesis AND T4→T3 conversion. Give BEFORE iodide.
- Iodide (potassium iodide or Lugol's solution) — Give 1 HOUR AFTER PTU to allow PTU to block synthesis first (Wolff-Chaikoff effect). Blocks thyroid hormone release.
- Steroids (hydrocortisone 100 mg IV q8h) — Blocks T4→T3 conversion; treats relative adrenal insufficiency from stress; anti-inflammatory.
- Treat the precipitant — Antibiotics if infection, cooling blankets for hyperthermia (avoid ASA — displaces T4 from binding proteins → worsens), fluids, dextrose-containing fluids, thiamine.
Why give PTU BEFORE iodide? If iodide is given first, it provides substrate for the thyroid to make even MORE hormone. PTU must block synthesis first — then iodide safely blocks hormone RELEASE.
Thyroid Storm Nursing Priorities
- ICU admission — continuous cardiac monitoring, hourly vitals
- Cooling blankets for hyperthermia; IV acetaminophen (NOT aspirin)
- High-flow oxygen; prepare for intubation
- Large-bore IV access; fluid resuscitation (high output cardiac failure)
- Cardiac monitoring — treat A-Fib with beta-blockade; avoid digoxin (unreliable in hyperthyroid state)
- Hourly neuro assessment
- Blood glucose monitoring (hyperthyroidism depletes glycogen stores)
- Identify and treat precipitant aggressively
4. Hypothyroidism
Causes
- Primary (most common): Hashimoto's thyroiditis (autoimmune — anti-TPO antibodies), post-RAI/thyroidectomy, iodine deficiency (worldwide leading cause), medications (amiodarone, lithium, interferon)
- Secondary: Pituitary failure → low TSH → low T4
- Tertiary: Hypothalamic failure → low TRH → low TSH → low T4
Signs & Symptoms of Hypothyroidism
Think: Everything is SLOW and COLD
- Cardiovascular: Bradycardia, low cardiac output, diastolic hypertension, pericardial effusion, dyslipidemia
- Metabolic: Cold intolerance, weight gain, hypothermia, fatigue
- Neurologic: Depression, cognitive slowing, lethargy, hyporeflexia (delayed relaxation phase — classic NCLEX sign), carpal tunnel syndrome
- GI: Constipation, ileus
- Skin/Hair: Dry coarse skin, hair loss (including outer third of eyebrows — classic), puffiness/edema, macroglossia, hoarseness
- Reproductive: Menorrhagia, infertility
- Myxedema: Non-pitting edema from glycosaminoglycan accumulation — face, hands, tongue, periorbital
Levothyroxine (Synthroid) Treatment
- Take 30–60 min before breakfast on empty stomach (food impairs absorption)
- Wait 4 hours after taking calcium, iron, antacids (bind levothyroxine in GI tract)
- Start low in elderly and cardiac patients — can precipitate angina or MI if dose too high initially
- Monitor TSH 6–8 weeks after dose change; once stable → annually
- Pregnancy: TSH goal 0.1–2.5 mU/L; dose typically increases 25–30% in pregnancy
- Lifelong therapy for Hashimoto's and post-thyroidectomy patients
5. Myxedema Coma
Life-threatening emergency — severe hypothyroidism leading to altered consciousness. Precipitants: cold exposure, infection, surgery, sedatives/narcotics, trauma, discontinuation of thyroid replacement.
Clinical Features
Myxedema Coma Hallmarks:
- Altered mental status → coma (stupor first, then coma)
- Hypothermia (core temp <35°C/95°F) — sometimes <30°C (86°F)
- Bradycardia (<50 bpm)
- Hypoventilation, hypercapnia, hypoxia
- Hypotension
- Hyponatremia (dilutional — SIADH-like)
- Hypoglycemia
- Classic myxedema features: puffiness, macroglossia, hoarseness, non-pitting edema
Myxedema Coma Treatment
| Intervention | Details |
|---|
| Airway/Ventilation | High intubation risk — hypoventilation + macroglossia; assist ventilation, prepare for intubation |
| IV Levothyroxine | 200–400 mcg IV loading dose (must be IV — gut absorption unreliable in shock), then 50–100 mcg/day IV until PO tolerated |
| Liothyronine (IV T3) | Some protocols add T3 5–20 mcg IV for faster effect; controversial — cardiac risk |
| Hydrocortisone | 100 mg IV q8h — always give BEFORE or WITH thyroid hormone (concurrent adrenal insufficiency in critically ill; thyroid hormone increases cortisol metabolism) |
| Passive rewarming ONLY | Warm blankets; NO active external rewarming (vasodilation → cardiovascular collapse) |
| Hyponatremia correction | Usually corrects with thyroid replacement; avoid rapid correction (osmotic demyelination) |
| Hypoglycemia treatment | Dextrose-containing IV fluids |
| Treat precipitant | Broad-spectrum antibiotics if infection suspected |
Active rewarming in myxedema coma = dangerous: Peripheral vasodilation causes cardiovascular collapse in an already severely bradycardic, hypotensive patient. Passive warming only.
6. Post-Thyroidectomy Nursing Care
Immediate Post-Op Complications
| Complication | Signs | Action |
|---|
| Hypocalcemia (parathyroid removal) | Chvostek's sign (+), Trousseau's sign (+), perioral tingling, muscle cramps, tetany, seizures | Monitor serial calcium; calcium gluconate IV for acute hypocalcemia; calcium carbonate + vitamin D PO |
| Recurrent laryngeal nerve injury | Hoarseness (unilateral), aphonia (bilateral — emergency airway) | Assess voice q1h; bilateral injury = stridor, respiratory distress → emergency tracheostomy |
| Hematoma/Bleeding | Swelling, tracheal deviation, stridor, difficulty swallowing | Keep suture removal kit at bedside; open incision if airway compromise imminent |
| Thyroid storm (post-op) | Hyperpyrexia, tachycardia, confusion (occurs within 12 hr post-op) | See thyroid storm protocol above |
Post-thyroidectomy nursing setup: Keep at bedside — calcium gluconate, suture removal kit, tracheostomy tray. Assess for Chvostek's (tap facial nerve) and Trousseau's (inflate BP cuff 20 mmHg above systolic × 3 min) every shift.
NCLEX High-Yield Thyroid Points
- Hyperthyroidism labs: Low TSH + High T4/T3; Hypothyroidism: High TSH + Low T4
- Most common hyperthyroid cause: Graves' disease (exophthalmos is hallmark)
- Most common hypothyroid cause: Hashimoto's (anti-TPO antibodies)
- Thyroid storm treatment order: Beta-blocker → PTU → Iodide (1 hour after PTU) → Steroids
- Iodide given AFTER PTU — never before (would worsen storm)
- Myxedema coma: passive warming only (active rewarming → cardiovascular collapse)
- Hypothyroidism classic neuro sign: delayed DTR relaxation phase
- Post-thyroidectomy priority: watch for hypocalcemia and recurrent laryngeal nerve injury
- Levothyroxine: take 30–60 min before breakfast; separate from calcium/iron by 4 hr
- Chvostek's sign (facial nerve tap → facial twitch) and Trousseau's sign (BP cuff → carpal spasm) = hypocalcemia
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