Beta-blockers (propranolol) used concurrently to control adrenergic symptoms (palpitations, tremor, sweating) — continue until euthyroid post-op.
Baseline vocal cord assessment — essential before any thyroid/parathyroid surgery. Documents pre-existing RLN palsy. If cord already paralysed pre-op, bilateral injury risk informed consent critical.
Corrected Ca²⁺ = measured Ca²⁺ + 0.02 × (40 − albumin). Baseline for post-op comparison. PTH confirms primary hyperparathyroidism (both elevated). Low PTH with high Ca²⁺ = non-PTH mediated hypercalcaemia.
Confirms euthyroid state before surgery. Low TSH = still hyperthyroid — delay surgery if Graves'. Elevated TSH post-thyroidectomy triggers levothyroxine replacement.
Ultrasound — thyroid nodule characterisation (TIRADS). CT neck/chest — retrosternal goitre, tracheal deviation. Sestamibi (Tc-99m) scan — localises parathyroid adenoma pre-op for minimally invasive parathyroidectomy.
| Complication | Rate | Notes |
|---|---|---|
| RLN injury (hoarseness) | 1–2% permanent | Up to 5% transient |
| Hypocalcaemia | Up to 30% transient | 1–2% permanent hypoparathyroidism |
| Haematoma | 1–2% | Airway emergency — life-threatening |
| Hypothyroidism | 100% (total) | Lifelong levothyroxine needed |
| Superior laryngeal nerve | <1% | Loss of high voice / singing |
Large goitre → anticipated difficult airway. Tracheal deviation, subglottic compression, retrosternal extension — all increase intubation difficulty.
AIRWAY IS PRIORITY #1. Wound haematoma can develop rapidly (within hours of surgery) and compress the trachea causing acute airway obstruction. A haematoma box must be at the bedside of every thyroid/parathyroid patient.
Must be present at ALL thyroid/parathyroid patients' bedsides for the first 24 hours post-op. Do not remove without surgical team authorisation.
| Sign | Significance |
|---|---|
| Stridor | Tracheal compression — emergency |
| Neck swelling | Haematoma accumulating |
| Voice change (new) | Pressure on RLN or tracheal shift |
| Difficulty swallowing | Oesophageal compression |
| Agitation / restlessness | Hypoxia — late sign |
| Drain output >50 ml/h | Active bleeding — review urgently |
Drain output monitoring: Check drain q1h for first 4h, then q2h. Document colour (fresh blood vs. serosanguinous). Saturated dressings = urgent surgical review.
| Timing | Action |
|---|---|
| Immediately post-extubation | Ask patient to speak — compare to pre-op baseline voice |
| Day 1 post-op | Voice quality assessment — hoarseness, breathiness, volume |
| At discharge | Document voice status; refer SLT if hoarse |
| 6-week follow-up | Laryngoscopy if voice not resolved; ENT referral |
| Parameter | Frequency |
|---|---|
| Airway / respiratory observations | Q1h first 6h, then Q2h |
| Drain output + colour | Q1h first 4h |
| Wound inspection | Q2h first 12h |
| Voice assessment | Post-extubation, Day 1 |
| Corrected Ca²⁺ | 6h, 24h, 48h |
| PTH (intra/post-op) | 1–4h post-op |
| TFTs (total thyroidectomy) | Day 1–2 |
| BP, HR, SpO₂, temp | Q4h |
Hypoparathyroidism is the most feared complication of total thyroidectomy. PTH drops → Ca²⁺ falls. Onset typically day 1–3 post-op. Monitor proactively — do not wait for symptoms.
| Timing | Test | Purpose |
|---|---|---|
| 1–4h post-op | PTH (intraop/early) | PTH <1 pmol/L = high risk for severe hypocalcaemia |
| 6h post-op | Corrected Ca²⁺ | First post-op baseline |
| 24h post-op | Corrected Ca²⁺ | Main monitoring point — most hypocalcaemia evident |
| 48h post-op | Corrected Ca²⁺ + PTH | Trend — improving or worsening |
| Discharge day | Ca²⁺ + phosphate + Mg²⁺ | Oral supplementation adequacy |
PTH <1 pmol/L at 1–4h post-op — high risk for severe hypocalcaemia. Start prophylactic oral calcium + calcitriol immediately without waiting for Ca²⁺ to fall.
| Severity | Ca²⁺ Level | Symptoms | Management |
|---|---|---|---|
| Mild | 1.9–2.1 mmol/L | Asymptomatic or mild tingling | Oral calcium carbonate 500–1000 mg TDS + calcitriol 0.25–0.5 mcg BD. Monitor Ca²⁺ q12–24h. Ensure adequate oral intake. |
| Moderate | 1.7–1.9 mmol/L | Symptomatic tingling, cramps, positive Chvostek/Trousseau | IV calcium gluconate 10 ml of 10% (= 2.25 mmol Ca²⁺) over 10 min SLOWLY via large-bore IV. Then oral calcium + calcitriol. Repeat Ca²⁺ in 2–4h. |
| Severe / Symptomatic | <1.7 mmol/L or tetany / laryngospasm | Tetany, laryngospasm, seizures, arrhythmia | IV calcium gluconate bolus THEN infusion: 40–50 ml of 10% in 1L 5% dextrose over 4–8h. Continuous cardiac monitoring (QTc). ICU/HDU consideration. Repeat Ca²⁺ q2–4h. |
IV calcium gluconate administration — MUST be given SLOWLY (10 min minimum for bolus dose). Rapid administration causes bradycardia, hypotension, and cardiac arrest. Never give IV calcium as a fast push. Extravasation causes severe tissue necrosis — use a large-bore peripheral IV or central line.
Note: Calcium gluconate preferred over calcium chloride peripherally — less irritating to veins. Calcium chloride (3x the elemental Ca²⁺) reserved for cardiac arrest or central line use.
Both RLNs supply all intrinsic laryngeal muscles except cricothyroid. Innervate posterior cricoarytenoid (PCA) — the only abductor of the vocal cords. Bilateral injury = both cords adducted → stridor.
| Feature | Unilateral RLN Injury | Bilateral RLN Injury |
|---|---|---|
| Voice quality | Hoarse, breathy, weak | Variable — may be near normal initially |
| Breathing | Usually adequate | Inspiratory stridor, dyspnoea — emergency |
| Swallowing | Aspiration risk (liquids) | Severe aspiration risk |
| Cord appearance (laryngoscopy) | One cord immobile / paramedian position | Both cords adducted / midline |
| Immediate management | SLT referral, monitoring, voice therapy | Consider reintubation / emergency tracheostomy |
| Long-term management | Voice therapy, possible medialisation thyroplasty | Cordotomy / arytenoidectomy to widen airway |
| Prognosis (transient) | 80–90% resolve within 6–12 months | Less predictable; permanent in some |
IONM tube positioning must be verified by anaesthetist — if tube rotates, electrode-cord contact lost and signal unreliable.
Second operation after diagnostic hemi-thyroidectomy (lobectomy) when histology confirms malignancy requiring completion.
Central compartment (level VI) or lateral neck dissection (levels II–V) for thyroid cancer lymph node involvement.
Rare but life-threatening. Occurs post-op in inadequately prepared hyperthyroid patients. Mortality up to 20% even with treatment.
High-yield exam content for DHA, DOH, SCFHS, QCHP, and MOH licensing exams. Focus on hypocalcaemia signs, IV calcium dosing, RLN injury comparison, and post-op monitoring schedules.
Technique: Tap facial nerve (CN VII) just anterior to tragus of the ear (over the parotid gland). Positive result: Ipsilateral facial muscle twitch (orbicularis oris / facial muscles contract). Significance: Indicates neuromuscular irritability from hypocalcaemia. Less specific — can be positive in 25% of normal people.
Technique: Inflate sphygmomanometer cuff 20 mmHg above systolic blood pressure for 3 minutes. Positive result: Carpal spasm — wrist flexion, MCP joint flexion, IP joint extension, thumb adduction ("accoucheur's hand" / "main d'accoucheur"). More specific than Chvostek's. Positive in <1% of normocalcaemic people.
Prolonged QT interval — most common ECG finding. Caused by prolonged phase 2 action potential. Risk of torsades de pointes and ventricular fibrillation. Monitor ECG in severe hypocalcaemia / IV calcium infusion.
| Indication | Dose & Rate |
|---|---|
| Moderate symptomatic | 10 ml of 10% calcium gluconate (= 2.25 mmol Ca²⁺) IV over 10 minutes SLOWLY |
| Severe / tetany / laryngospasm | 40–50 ml of 10% in 1L 5% dextrose infused over 4–8 hours. Titrate to symptoms and Ca²⁺ level. |
| Cardiac arrest (hypocalcaemic) | 10 ml 10% calcium gluconate IV rapid push (or calcium chloride 10 ml 10%) |
Never mix calcium gluconate with sodium bicarbonate or phosphate solutions — precipitates calcium carbonate. Never give fast IV push except cardiac arrest — causes bradycardia/arrest.
| Feature | Unilateral RLN | Bilateral RLN | SLN (External Branch) |
|---|---|---|---|
| Voice | Hoarse, breathy | Variable (may be near normal initially) | Loss of high pitch, monotone |
| Airway | Patent | Stridor, distress — EMERGENCY | Patent |
| Aspiration | Liquids (silent aspiration) | Severe | Minimal |
| Cord position | Paramedian (one cord) | Both adducted to midline | Cord lax / asymmetric tension |
| Immediate action | SLT, voice therapy, observe | Reintubation / tracheostomy | SLT referral |
| Muscle affected | All intrinsic muscles except cricothyroid | All intrinsic muscles except cricothyroid | Cricothyroid only |
| Time | Key Actions |
|---|---|
| Immediate post-extubation | Voice assessment; airway obs; haematoma box at bedside |
| 0–6h | Q1h airway + drain obs; voice check; Ca²⁺ at 6h |
| 6–24h | Q2h obs; Ca²⁺ at 24h; PTH check if not done |
| 24–48h | Ca²⁺ at 48h; swallowing assessment; drain removal criteria |
| Discharge | Ca²⁺ + PO₄ + Mg²⁺; TFTs; levothyroxine commenced (total thyroidectomy); Ca/calcitriol if needed; voice documented; SLT referral if indicated |
| 6 weeks | TFTs; Ca²⁺; histology review; voice + laryngoscopy if hoarse; oncology referral (cancer) |
Wolff–Chaikoff effect: high iodine load transiently inhibits thyroid hormone synthesis and reduces gland vascularity. Given 7–14 days pre-op. Must NOT be given without prior anti-thyroid drug cover (can cause transient hyperthyroidism if given alone).
Corrected Ca²⁺ = Measured Ca²⁺ + 0.02 × (40 − albumin g/L). Normal range: 2.2–2.6 mmol/L. Use corrected Ca²⁺ for clinical decisions in post-op patients (albumin often low post-surgery → measured Ca²⁺ falsely low).
Most common thyroid cancer (80%). Excellent prognosis — 20-year survival >95% for low-risk. Spreads to regional lymph nodes (not blood-borne initially). PTC has characteristic Psammoma bodies, Orphan Annie nuclei on histology. Often multifocal. Post-total thyroidectomy: RAI remnant ablation for high-risk; TSH suppression with levothyroxine.
Bones, Stones, Groans, and Psychic Moans. Bones = subperiosteal resorption, osteitis fibrosa cystica, "brown tumours". Stones = nephrolithiasis, nephrocalcinosis. Groans = constipation, nausea, peptic ulcer. Moans = depression, cognitive impairment, psychosis. Biochemistry: high Ca²⁺ + high PTH + low phosphate + high urinary Ca²⁺.
Post-parathyroidectomy in severe primary hyperparathyroidism — bones rapidly re-mineralise and take up calcium. Results in severe, prolonged hypocalcaemia. Requires large IV and oral calcium + calcitriol supplementation. Also hypomagnesaemia and hypophosphataemia. Different from transient hypoparathyroidism — PTH recovers but Ca²⁺ remains low due to bone uptake.