Thyroid Disorders Nursing Guide

Thyroid Hormone Pathway

Hypothalamic-Pituitary-Thyroid (HPT) Axis

Hypothalamus
Releases TRH (Thyrotropin-Releasing Hormone)

↓ TRH travels via portal blood ↓

Anterior Pituitary
Releases TSH (Thyroid-Stimulating Hormone)

↓ TSH via systemic circulation ↓

Thyroid Gland
Produces T4 (thyroxine) & T3 (triiodothyronine)

↑ NEGATIVE FEEDBACK — High T3/T4 suppresses TRH & TSH

Key conversion: ~80% of T3 is produced by peripheral conversion of T4 → T3 (mainly in liver & kidneys). T3 is the biologically active form (3-4× more potent than T4).

Normal Lab Reference Ranges

Test	Normal Range	Unit	Clinical Note
TSH	0.4 – 4.0	mIU/L	Best single screening test; most sensitive indicator
Free T4 (FT4)	12 – 22	pmol/L	Unbound fraction; not affected by TBG changes
Free T3 (FT3)	3.5 – 6.5	pmol/L	Active hormone; may be elevated first in hyperthyroidism
Thyroglobulin	1.5 – 38	ng/mL	Tumour marker post-thyroidectomy for papillary/follicular cancer
Calcitonin	< 10 (M) / < 5 (F)	pg/mL	Marker for medullary thyroid cancer
TPO Antibodies	< 35	IU/mL	Positive in Hashimoto's (>90%) and Graves' (~75%)
TSH Receptor Ab (TRAb)	< 1.75	IU/L	Confirmatory for Graves' disease

Interactive TSH / FT4 Interpreter

Enter values to get a clinical interpretation

TSH (mIU/L)

Free T4 (pmol/L)

Interpretation

Physical Assessment of the Thyroid

Goitre Palpation Technique

Stand behind the patient; ask them to slightly flex their neck
Place both thumbs on the posterior neck, fingers over the thyroid
Ask patient to swallow a sip of water — thyroid rises with swallowing
Note size, consistency (firm, soft, nodular), tenderness, bruit
Auscultate over the thyroid for a bruit (indicates hypervascular gland — Graves')

WHO Goitre Grading

Grade 0 — no palpable/visible goitre | Grade 1 — palpable but not visible | Grade 2 — visible with normal neck posture

Signs to Assess

Sign	Condition	How to Elicit
Lid lag	Hyperthyroidism	Look down slowly; sclera visible above iris
Exophthalmos	Graves' disease	View from above — eyes protrude beyond orbital rim
Tremor	Hyperthyroidism	Outstretched hands; paper placed on top
Brisk reflexes	Hyperthyroidism	Patellar/ankle reflex — fast relaxation phase
Slow relaxation reflex	Hypothyroidism	Ankle jerk — delayed return phase (classic)
Pretibial myxoedema	Graves' disease	Non-pitting oedema on shins, orange peel texture
Periorbital oedema	Hypothyroidism	Puffy eyelids, especially morning

Skin, Hair & Nails Assessment

Hypothyroid Changes

Dry, coarse, pale skin ("doughy" texture)
Diffuse alopecia; brittle nails
Loss of outer third of eyebrows (Hertoghe's sign)
Cold, yellow-tinged skin (carotenaemia)
Puffy face, periorbital and peripheral oedema

Hyperthyroid Changes

Warm, moist, velvety smooth skin
Fine hair, diffuse hair loss
Onycholysis (Plummer's nails — nails separate from bed)
Palmar erythema, hyperhidrosis
Pretibial myxoedema (Graves' specific)

GCC Regional Context

Iodine Deficiency in the Middle East

Historically, iodine deficiency was prevalent in GCC countries due to low dietary iodine intake. Mandatory salt iodisation programmes have improved but not eliminated deficiency. Goitre remains endemic in some inland areas.

Autoimmune Thyroid Disease

Hashimoto's thyroiditis and Graves' disease are increasingly prevalent in GCC. Vitamin D deficiency (endemic in region despite sun exposure due to indoor lifestyles) may contribute to higher autoimmune disease rates.

Thyroid Cancer in GCC

The UAE has one of the highest thyroid cancer incidence rates globally. Dubai Cancer Registry data show thyroid cancer is among the top cancers in females. Increased detection via expanding health screening programmes and ultrasound access are key drivers.

Types of Hypothyroidism

Primary Hypothyroidism

Problem lies in the thyroid gland itself.

Hashimoto's thyroiditis — autoimmune, most common cause worldwide
Post-radioactive iodine (RAI) therapy
Post-thyroidectomy
Iodine deficiency
Drugs: amiodarone, lithium, interferon

TSH ↑ FT4 ↓

Secondary / Central

Pituitary or hypothalamic failure.

Pituitary tumour, Sheehan's syndrome
Hypothalamic disease
TSH deficiency (panhypopituitarism)

TSH Low/Normal FT4 ↓

Note: TSH may be inappropriately "normal" — always check FT4.

Subclinical Hypothyroidism

Early/mild thyroid failure; often asymptomatic.

TSH mildly elevated (4–10 mIU/L)
FT4 remains within normal range
Risk of progression to overt hypothyroidism: ~5%/year (higher if TPO-Ab positive)

TSH 4–10 FT4 Normal

Symptoms — SLUG Mnemonic

SLUG — Classic Hypothyroid Symptoms

Slow heart rate — bradycardia, reduced cardiac output

Lethargy & fatigue — the most common presenting complaint

Underfunctioning gut — constipation, slow gastric emptying

Gaining weight + cold intolerance, dry skin, hair loss, depression, periorbital oedema, delayed reflexes, hoarse voice, carpal tunnel syndrome

Hashimoto's Thyroiditis

Pathophysiology

Autoimmune destruction of thyroid follicles
CD4+ T-cell mediated (Th1 response) + B-cell antibodies
TPO antibodies positive in >90%
Anti-thyroglobulin antibodies positive in ~80%
HLA-DR3 and HLA-DR5 associations
More common in females (F:M = 7:1)

Associated Autoimmune Conditions

Type 1 Diabetes Mellitus
Addison's disease (adrenal insufficiency)
Coeliac disease
Pernicious anaemia (Vitamin B12 deficiency)
Vitiligo, alopecia areata
Rheumatoid arthritis, SLE
Schmidt syndrome (polyglandular autoimmune syndrome type 2)

Hashimoto's Encephalopathy

Rare but serious complication: cognitive dysfunction, seizures, altered consciousness — responds to steroids. TSH-receptor antibodies may be elevated. Not directly caused by low thyroid hormones.

Levothyroxine Treatment

Dosing & Administration

Patient Group	Starting Dose
Healthy adult <60 yrs	1.6 mcg/kg/day (full dose)
Elderly / cardiac disease	12.5–25 mcg/day, titrate slowly
Subclinical hypothyroidism	25–50 mcg/day
Post-total thyroidectomy	1.6 mcg/kg/day from day 1
Pregnancy (new diagnosis)	Full replacement dose immediately

Administration Instructions (Patient Counselling)

Take on an empty stomach, first thing in the morning
Wait 30–60 minutes before food or other medications
Same time every day for consistent absorption
Do not crush or split tablets unnecessarily (some brands)

Drug Interactions — Reduce Absorption (Separate by 4 Hours)

Monitoring Protocol

Check TSH 6–8 weeks after starting or dose change. Target TSH: 0.5–2.5 mIU/L for most adults. Once stable, recheck annually. In pregnancy: check TSH every 4 weeks in 1st trimester, then at 26–28 weeks.

Levothyroxine in Pregnancy

Increase dose by 30–50% as soon as pregnancy is confirmed (extra 2 tablets per week is a simple instruction)
TSH targets: 0.1–2.5 mIU/L (1st trimester) | 0.2–3.0 (2nd) | 0.3–3.0 (3rd)
Untreated hypothyroidism → miscarriage, pre-eclampsia, fetal neurodevelopmental impairment
Postpartum thyroiditis: 5–10% of women; biphasic pattern (hyper then hypo); often self-limiting

Myxoedema Coma — Emergency

LIFE-THREATENING — Mortality 20–50% even with treatment

Precipitating Factors:

Cold exposure (classic GCC winter travel to cold climates)
Infection, sepsis
CNS depressants (opioids, sedatives)
Non-adherence to levothyroxine
Surgery / trauma

Clinical Features:

Hypothermia (core temp <35°C)
Bradycardia & hypotension
Respiratory failure (hypoventilation, CO2 retention)
Altered consciousness → coma
Hyponatraemia, hypoglycaemia

Management: IV T3 (liothyronine) 5–20 mcg every 8h AND/OR IV T4 200–400 mcg loading → IV hydrocortisone 100 mg 8-hourly (cover concomitant adrenal insufficiency) → active external warming → ICU ventilatory support → treat precipitant

Causes of Hyperthyroidism

Common Causes

Cause	Key Feature
Graves' disease	TSH-receptor antibodies (TRAb); most common cause; diffuse goitre; orbitopathy
Toxic multinodular goitre	Multiple autonomous nodules; older patients; common in iodine-deficient areas
Toxic adenoma	Single autonomous nodule; "hot" on scan; no orbitopathy
Thyroiditis (de Quervain's)	Subacute, painful; viral; transient hyperthyroidism → hypothyroidism → recovery
Amiodarone-induced	37% iodine content; type 1 (excess iodine) or type 2 (thyroiditis); difficult to treat
Iodine-induced (Jod-Basedow)	IV contrast, excessive iodine supplementation

THYROID Mnemonic — Symptoms

Tremor — fine, intention tremor; seen with paper test

Heat intolerance & hyperhidrosis; prefers cold

Youthful appetite — weight loss despite increased eating

Rapid heart rate — palpitations, AF, tachycardia (>100 bpm)

Ophthalmoplegia / exophthalmos — Graves' specific; lid lag

Irritability — anxiety, restlessness, emotional lability

Diarrhoea — increased gut motility, frequent loose stools

Graves' Orbitopathy (Thyroid Eye Disease)

Features

Proptosis (exophthalmos) — corneal exposure risk
Lid retraction, lid lag, periorbital oedema
Diplopia (restrictive myopathy — inferior rectus)
Optic nerve compression (vision loss — emergency)
CLINICAL ACTIVITY SCORE (CAS) used to guide treatment

Management

Lubricating eye drops — moisture protection; elevate head of bed
Selenium 200 mcg/day × 6 months — mild-moderate disease
IV methylprednisolone — moderate-severe, active disease
Orbital radiotherapy — restricted indications
Orbital decompression surgery — sight-threatening
Smoking cessation — major risk factor for progression
Maintain euthyroid state — avoid hypothyroidism (worsens orbitopathy)

Treatment Options for Hyperthyroidism

Anti-Thyroid Drugs (ATDs)

Drug	Preferred Indication	Dose	Key Nursing Points
Carbimazole	First-line (most patients)	Starting: 20–40 mg/day; maintenance 5–15 mg/day	Monitor FBC; warn about agranulocytosis (stop immediately with fever/sore throat)
Propylthiouracil (PTU)	Pregnancy (1st trimester); thyroid storm; allergy to carbimazole	200–600 mg/day in 3 divided doses	Also blocks T4→T3 conversion (extra benefit in crisis). Risk of liver failure — monitor LFTs

Agranulocytosis — Urgent Warning

Occurs in ~0.3% of patients. Presents as fever, sore throat, mouth ulcers. Patient must be instructed: STOP the drug, seek emergency blood count (FBC) immediately. Do NOT restart ATD if neutrophils <1.5 × 10⁹/L.

Radioactive Iodine (RAI / I-131)

Definitive treatment — destroys thyroid tissue
Single oral dose; results in hypothyroidism in most (>80%)
Takes 6–12 weeks for full effect
Contraindicated: pregnancy, breastfeeding, active moderate-severe orbitopathy
Post-RAI: avoid close contact <1 m for 7 days; no pregnancy for 6 months (both sexes)
Pre-treat with ATDs if severely thyrotoxic; stop 5–7 days before RAI

Surgery — Thyroidectomy

Total thyroidectomy: definitive; followed by levothyroxine lifelong
Subtotal: less common; risk of recurrence
Indications: large goitre, nodules needing biopsy, failed ATD, patient preference, RAI-contraindicated
Require euthyroid state pre-op (ATDs + Lugol's iodine for 10 days)
Complication: hypoparathyroidism, recurrent laryngeal nerve injury, haemorrhage

Beta-Blockers — Symptomatic Control

Propranolol 40–80 mg 3× daily (or atenolol 50–100 mg once daily). Controls: tachycardia, palpitations, tremor, anxiety, heat intolerance. Does NOT reduce thyroid hormone production — used while waiting for ATDs to work (takes 4–8 weeks). Also blocks peripheral T4→T3 conversion (propranolol).

Thyroid Storm (Thyrotoxic Crisis) — Emergency

LIFE-THREATENING — Mortality 10–30% with treatment

Precipitating Factors:

Infection / sepsis (most common)
Surgery or trauma
Iodine load (contrast, amiodarone)
Non-adherence to ATDs
Diabetic ketoacidosis
Pulmonary embolism

Clinical Features (Burch-Wartofsky Criteria):

Fever >38.5°C (often >40°C)
Heart rate >140 bpm; atrial fibrillation
CNS dysfunction: delirium, psychosis, seizures, coma
Cardiac failure, pulmonary oedema
Nausea, vomiting, jaundice

Management (Give in ORDER — timing matters!):

PTU 600 mg loading then 200–300 mg every 6h (blocks synthesis AND T4→T3 conversion)
Lugol's iodine (60 drops/day in divided doses) — give at least 1 hour AFTER PTU (prevents iodine from being used to make more hormone)
Propranolol IV or oral — control HR; block peripheral T4→T3 conversion
Hydrocortisone 100 mg IV 8-hourly — blocks T4→T3 conversion; covers adrenal insufficiency
Active cooling (paracetamol, cooling blankets — NOT aspirin as it displaces T4 from binding protein)
ICU admission; treat precipitant (antibiotics if infection)

Indications for Thyroid Surgery

Malignancy

Confirmed or suspected thyroid cancer
Suspicious/indeterminate nodule (Bethesda IV–VI)
Medullary thyroid cancer (prophylactic in RET mutation carriers)

Compressive Goitre

Dysphagia, dyspnoea, stridor
Substernal extension
Cosmetically unacceptable large goitre

Hyperthyroidism

Graves' disease — failed ATDs or patient preference
RAI contraindicated (pregnancy, active orbitopathy)
Toxic multinodular goitre with large size

Pre-Operative Preparation

Medical Preparation

Achieve euthyroid state before surgery (reduces intra-operative haemorrhage and thyroid storm risk)
Carbimazole or PTU for 6–8 weeks pre-op until euthyroid
Lugol's iodine 3 drops TDS for 10 days pre-op — reduces gland vascularity (Wolff-Chaikoff effect)
Beta-blockers continued until day of surgery
Baseline calcium and PTH levels

Pre-Op Nursing Assessment

Voice assessment — document baseline voice quality (laryngoscopy if planned)
Swallowing assessment
Airway assessment — check for tracheal deviation
Serum calcium, phosphate, PTH baseline
Coagulation profile, group & save
Ensure patient understands post-op monitoring requirements

Post-Operative Monitoring (Hourly × 24h)

PRIORITY 1 — HAEMORRHAGE & AIRWAY EMERGENCY

Expanding haematoma in neck = airway compression. Patient may deteriorate rapidly. Maintain bedside tracheostomy kit at all times. Signs: stridor, increasing swelling, patient unable to swallow, tracheal deviation. If haematoma: open wound immediately at bedside (clip/suture removal) → call surgical team → theatre.

Hypocalcaemia (Hypoparathyroidism)

Most common significant complication post-thyroidectomy (transient in 10–30%; permanent in 1–2%)

Signs & Symptoms:

Perioral tingling/numbness (earliest symptom)
Tingling in fingers and toes
Muscle cramps, tetany
Seizures (severe)

Clinical Signs:

Chvostek's Sign: Tap the facial nerve (2 cm anterior to the earlobe, below the zygomatic arch). Positive = ipsilateral twitching of facial muscles. Present in hypocalcaemia.

Trousseau's Sign: Inflate BP cuff above systolic BP for 3 minutes. Positive = carpal spasm (thumb adduction, MCP flexion — "main d'accoucheur"). More specific for hypocalcaemia than Chvostek's.

Treatment

Mild/symptomatic: oral calcium carbonate 1–2 g 3× daily + calcitriol 0.25 mcg BD.
Severe/tetany/seizures: IV calcium gluconate 10 mL of 10% solution slow IV over 10 min (NOT calcium chloride peripherally — tissue necrosis risk) → calcium gluconate infusion. Monitor ECG.

Laryngeal Nerve Injury

Recurrent Laryngeal Nerve (RLN):

Unilateral: hoarse voice, weak cough, aspiration risk → speech therapy
Bilateral: stridor, respiratory distress → may need tracheostomy (emergency)
Assess voice post-op: ask patient to say "eee" and count to 10
Risk: 1% permanent; 5% transient (neuropraxia)

Superior Laryngeal Nerve (SLN):

Loss of high-pitched phonation; voice fatigue
Important for singers / teachers

Nursing Action

Intraoperative nerve monitoring (IONM) is standard of care. Report any voice change to surgeon immediately post-op. Nil by mouth until swallowing assessment if bilateral RLN suspected.

Calcium Monitoring Protocol

Timing	Action	Target
4–6 hours post-op	Serum calcium + PTH (if available)	Ca >2.0 mmol/L; PTH >1.6 pmol/L (predicts recovery)
First post-op morning	Serum calcium	Ca >2.0 mmol/L; if declining, start oral calcium
Daily while inpatient	Serum calcium	Ca >2.0 mmol/L; check for symptoms
1 week post-discharge	Outpatient calcium check	Trend monitoring; adjust supplementation

Prophylactic vs Reactive Calcium Strategy

Many centres start prophylactic oral calcium + calcitriol for all total thyroidectomy patients for first 2 weeks, given the high rate of transient hypoparathyroidism. Discuss local protocol with surgical team.

Discharge Advice

Wound Care

Keep wound dry for 48 hours
Steri-strips / dressings as per local protocol
No swimming or submerging wound for 2 weeks
Scar massage with vitamin E cream from 3–4 weeks post-op
Sun protection of scar for 6–12 months (SPF50)
Seek care if: redness, swelling, discharge, fever >38°C

Medications & Follow-Up

Total thyroidectomy: start levothyroxine day 1–2 post-op (1.6 mcg/kg/day)
For thyroid cancer: TSH-suppressive doses (target TSH <0.1 mIU/L initially)
Calcium supplements + calcitriol until PTH recovers (weeks to months)
Avoid strenuous activity, heavy lifting >5 kg for 4 weeks
Driving: check local guidelines (usually 1–2 weeks)
Outpatient TFT + calcium check at 4–6 weeks

Radioactive Iodine Safety (Post-RAI)

Radiation Safety Instructions for Patient & Family

Maintain >1 metre distance from others for 7 days (especially children and pregnant women)
Sleep alone for 7–14 days (dose-dependent)
Use separate utensils, towels, toilet
Flush toilet twice after use
No pregnancy for 6 months (both male and female patients)

Avoid breastfeeding: stop before RAI and do not restart
Stay off work for 5–7 days (especially if in contact with children/pregnant women)
Keep distance from pets (especially lap dogs/cats)
Increase fluid intake and frequent urination to speed iodine excretion
Sucking lemon sweets increases salivary gland clearance of iodine

Low-Iodine Diet Pre-RAI (2 weeks before)

Avoid: iodised salt, seafood, dairy products, commercial bread, red dye No.3 (E127), amiodarone. Purpose: maximise thyroid uptake of therapeutic I-131 by depleting iodine stores.

Type	Frequency	Origin	Spread	Marker	Prognosis
Papillary	~80%	Follicular cells	Lymph nodes (regional)	Thyroglobulin (post-op); BRAF V600E mutation	Excellent (>95% 10-yr survival)
Follicular	~10%	Follicular cells	Haematogenous (bone, lung)	Thyroglobulin; RAS mutations; PAX8/PPARγ	Good (stage-dependent)
Medullary	~5%	Parafollicular C-cells	Lymph nodes & haematogenous	Calcitonin (diagnostic + surveillance); CEA; RET mutation	Moderate (70% 10-yr)
Anaplastic	<2%	Follicular cells (dedifferentiated)	Rapid local invasion + distant	None specific; diagnosis by biopsy	Very poor (<20% 1-yr)
Lymphoma	<1%	Thyroid lymphoid tissue	Lymph nodes	Associated with Hashimoto's; B-cell type	Variable (responds to chemo/radio)

TSH	FT4	Interpretation
↑↑ High	↓ Low	Primary Hypothyroidism
↑ Mildly High	Normal	Subclinical Hypothyroidism
Normal/Low	↓ Low	Central (Secondary) Hypothyroidism
↓↓ Low	↑↑ High	Overt Hyperthyroidism
↓ Low	Normal	Subclinical Hyperthyroidism
Normal	Normal	Euthyroid

Sign	Method	Positive Response	Specificity
Chvostek's	Tap facial nerve (2 cm anterior & inferior to earlobe)	Ipsilateral facial muscle twitch	Lower — can be positive in 25% normocalcaemic
Trousseau's	BP cuff above systolic for 3 min (inflate to 20 mmHg above systolic)	Carpal spasm — thumb adduction, finger extension (obstetric hand)	Higher — more specific for true hypocalcaemia