Complications of Thyroidectomy

1. Hemorrhage / Wound Hematoma

• An arterial bleed raises tension in the central compartment, compressing venous outflow of the larynx - venous edema of the larynx can develop rapidly, causing airway obstruction and death.
• Wound hematoma may also distort airway anatomy, making intubation difficult.
• Clinical signs: pain, oozing from the incision, ecchymosis, firm swelling, stridor.
• Treatment: immediate bedside removal of skin sutures to release pressure, endotracheal intubation to secure the airway, followed by formal wound exploration and bleeding vessel control in the operating room.
• Wound drains have NOT been shown to have a protective effect.
• This is the reason thyroidectomy remains an inpatient procedure in many countries (e.g., the UK).

2. Recurrent Laryngeal Nerve (RLN) Injury

• UK audit (BAETS): RLN palsy rate of 1.8% at 1 month, declining to 0.5% at 3 months for first-time operations. Permanent paralysis is rare when the nerve is identified.
• Preoperative voice evaluation is essential for any patient with subjective voice changes or prior anterior neck surgery.
• If the nerve is transected and both ends identified intraoperatively, reanastomosis should be attempted. If a segment is excised (e.g., due to malignant invasion), ansa cervicalis anastomosis can be considered to maintain laryngeal muscle tone and improve voice quality.
• Permanent unilateral cord paralysis: conservative management with speech therapy; if voice remains unacceptable, medialization procedures can be performed.

3. External Branch of the Superior Laryngeal Nerve (EBSLN) Injury

• More common than appreciated because of the nerve's proximity to the superior thyroid artery during ligation.
• Results in loss of vocal cord tension - diminished power, pitch range, and singing ability.
• Changes are subtle for most patients but significant for professional voice users (singers, teachers, lawyers).
• Patients must be counseled preoperatively that any thyroid operation can change the voice even without overt nerve trauma.

4. Hypoparathyroidism and Hypocalcemia

• Inadvertent removal of parathyroid glands
• Devascularization/infarction of parathyroid end arteries (more common than actual removal)

• Permanent hypoparathyroidism after total thyroidectomy: <1% in experienced hands; ~10% in some series with central neck dissection.
• Limited to total thyroidectomy - lobectomy spares contralateral glands.
• Total thyroidectomy + central neck dissection places parathyroids at greatest risk.

5. Hypothyroidism

• Inevitable after total thyroidectomy - lifelong thyroxine replacement required.
• After lobectomy: approximately 1 in 3 patients will require supplementation; rates are higher in those with thyroid autoantibodies.
• Subtotal thyroidectomy (leaving a remnant) has largely been abandoned because of difficulty judging remnant adequacy and the risk of recurrence requiring difficult revision surgery.

6. Thyroid Storm (Thyrotoxic Crisis)

• Rare but life-threatening - occurs in 1%-5% of hospitalized thyrotoxic patients; mortality up to 25%.
• Triggered by thyroid manipulation in a patient who is not biochemically euthyroid preoperatively (inadequate preparation).
• Onset: usually 6-24 hours postoperatively, but can occur intraoperatively.
• Key distinguishing feature from malignant hyperthermia: no muscle rigidity, no elevated CK, no lactic/respiratory acidosis.
• Clinical features: hyperpyrexia, tachycardia, altered consciousness (agitation, delirium, coma), hypotension.
• Treatment:
  • IV fluids and cooling
  • IV beta-blocker (esmolol, target HR <100)
  • Propylthiouracil (PTU) 250-500 mg every 6h
  • Sodium iodide 1 g IV over 12h (given AFTER PTU)
  • Hydrocortisone 100-200 mg every 8h
  • Propranolol for adrenergic blockade
• Burch-Wartofsky scoring system (1993) is used for clinical diagnosis based on temperature, CNS manifestations, GI-hepatic dysfunction, cardiovascular dysfunction, and precipitating factors.

7. Other Complications

Summary Table

Thyroidectomy Complications - Classifications

Division 1: By Timing

Immediate (Intraoperative)

• Hemorrhage / major vessel injury
• RLN injury (transection)
• Tracheal injury
• Esophageal injury
• Pneumothorax (especially retrosternal goiter)
• Thyroid storm (intraoperative trigger)

Early Postoperative (Hours to Days)

• Reactionary hemorrhage / wound hematoma (most within first 24h)
• Airway obstruction (from hematoma, tracheomalacia, or bilateral RLN palsy)
• Acute hypocalcemia / hypoparathyroidism (12-72h)
• Thyroid storm (6-24h post-op)
• Wound infection
• Seroma

Late Postoperative (Weeks to Months/Years)

• Permanent RLN palsy
• Permanent hypoparathyroidism
• Hypothyroidism (inevitable after total thyroidectomy)
• Keloid / hypertrophic scar
• Recurrence of disease (e.g., goiter after subtotal thyroidectomy)

Division 2: By Type (Surgical vs. Medical)

Surgical Complications

Medical Complications

Division 3: By Reversibility

Transient

• Transient RLN palsy (resolves within weeks; much more common than permanent)
• Transient hypocalcemia (up to 30% after total thyroidectomy)
• Seroma, wound hematoma (after evacuation)
• Thyroid storm (if treated promptly)

Permanent

• Permanent RLN palsy (<1% when nerve identified)
• Permanent hypoparathyroidism (<1%; higher with central neck dissection)
• Hypothyroidism (after total thyroidectomy - permanent by design)
• EBSLN injury (usually permanent)
• Tracheomalacia

Division 4: By Nerve Involved

Division 5: Specific to Operation Type

Quick Memory Aid

"HINT" = common serious complications

• H - Hemorrhage / Hematoma
• I - Injury to RLN (and EBSLN)
• N - No calcium (Hypoparathyroidism)
• T - Thyroid storm / Thyroid insufficiency