Thyroidectomy (Lobectomy / Total)
Procedure Snapshot
- Indication: Thyroid nodules, differentiated thyroid carcinoma, Graves’ disease, large goiter with compressive symptoms.¹
- Expected duration: 60–120 minutes for lobectomy; 120–180 minutes for total thyroidectomy.¹
- Special instruments: Nerve integrity monitor, bipolar/Ligasure, Harmonic scalpel, self-retaining retractors.¹
Step Workflow
- Exposure
- Supine with neck extended; shoulder roll; slight anti-Trendelenburg.¹
- Transverse Kocher incision two fingerbreadths above sternal notch.¹
- Raise subplatysmal flaps to thyroid cartilage superiorly and sternal notch inferiorly.¹
- Midline & Strap Muscles
- Identify midline raphe; separate sternohyoid and sternothyroid muscles.¹
- Retract laterally (divide strap muscles only if exposure inadequate).¹
- Mobilization
- Rotate thyroid lobe medially.
- Divide middle thyroid vein to free lateral lobe.¹
- Superior Pole
- Identify superior thyroid vessels; ligate close to capsule to protect external branch of superior laryngeal nerve (EBSLN).¹
- Parathyroids
- Identify superior parathyroid deep/dorsal to RLN and inferior parathyroid ventral to RLN near lower pole.¹
- Preserve vascular pedicles; autotransplant if devascularized.¹
- Recurrent Laryngeal Nerve
- Identify in tracheoesophageal groove, typically in Simon’s triangle (carotid laterally, esophagus medially, ITA superiorly).¹
- Keep nerve in situ; avoid traction and thermal spread.¹
- Berry’s Ligament
- Divide sharply while maintaining continuous visualization of the RLN (nerve lies < 3 mm from ligament).¹
- Hemostasis & Removal
- Remove the lobe (lobectomy) or proceed to contralateral side (total).¹
- Irrigate; Valsalva; meticulous hemostasis.¹
Key Pimp Questions
-
Q: Where does the RLN run?
A: In the tracheoesophageal groove, entering the larynx just behind Berry’s ligament.¹ -
Q: What is the cause of post-op hypocalcemia?
A: Parathyroid devascularization or inadvertent parathyroid removal → temporary or permanent hypoparathyroidism.¹ -
Q: What nerve is at risk during superior pole dissection?
A: External branch of the superior laryngeal nerve (EBSLN).¹ -
Q: What is the incidence of transient hypocalcemia after total thyroidectomy?
A: ~20%.¹ -
Q: Permanent hypocalcemia?
A: ~1–5%.¹
Critical Anatomy
- Landmarks:
- Recurrent laryngeal nerve (RLN)
- External branch of superior laryngeal nerve (EBSLN)
- Superior/inferior parathyroid glands
- Berry’s ligament
- The Tubercle of Zukerkandl is a pyramidal enlargement of the lateral edge of the thyroid lobe that stems from the fusion of the lateral and medial thyroid anlages. The tubercle usually projects lateral to the RLN. Elevating the tubercle allows the RLN to be readily located. Less commonly the RLN courses lateral to an enlarged tubercle; this places the nerve at risk of injury. The superior parathyroid gland, also derived from the 4th branchial cleft, is commonly located close to and cephalad to the tubercle.
- Danger zones:
- RLN (< 3 mm from Berry’s ligament)¹
- EBSLN near superior thyroid artery branches¹
- Parathyroid blood supply from ITA branches¹
Informed Consent Highlights
- Hoarseness (RLN injury) — 0–28% transient; ~1% permanent¹
- Hypocalcemia — 20% transient; 1–5% permanent¹
- Hematoma — ~1% (airway emergency)¹
- Voice change (EBSLN) — <5% subtle dysphonia¹
- Infection/seroma — uncommon¹
Post-op Considerations
- Calcium / PTH: Check at 24 h; monitor for 48 h if total.¹
- Symptoms of hypocalcemia: Perioral tingling, paresthesias, carpopedal spasm → treat promptly with IV/PO calcium.¹
- Voice check: Evaluate for dysphonia; laryngoscopy if concern.¹
- Drain: Optional; remove when <50 ml/24 h.¹
- Thyroxine: Begin immediately post-operatively unless delaying for radioactive iodine.¹
- Diet: Normal PO next morning.¹
Clinical Pearls
- Divide superior pole vessels close to the thyroid capsule to avoid EBSLN injury.¹
- RLN must be visualized at Berry’s ligament before division of the ligament.¹
- Superior parathyroid is located dorsal to RLN; inferior parathyroid ventral.¹
- Harmonic scalpel safely reduces operative time without increasing complication rate.¹
- If a parathyroid is devascularized → mince and autotransplant into SCM.¹
Quick Reference Table
| Complication | Incidence | Notes |
|---|---|---|
| Transient RLN palsy | 0–28%¹ | Most resolve within weeks |
| Permanent RLN injury | ~1%¹ | Hoarseness |
| Transient hypocalcemia | ~20%¹ | Most after total thyroidectomy |
| Permanent hypocalcemia | 1–5%¹ | Parathyroid loss/devascularization |
| Post-op hematoma | ~1%¹ | Airway emergency |
| EBSLN injury | <5%¹ | Loss of pitch |
Quick-Reference Cards
Key Anatomy
- RLNIn tracheoesophageal groove; within 3 mm of Berry’s ligament.¹
- EBSLNAt risk during superior pole ligation.¹
- ParathyroidsSuperior dorsal to RLN; inferior ventral.¹
- Middle thyroid veinKey structure for mobilizing lobe.¹
Post-Op Management
- Calcium/PTHCheck at 24 h; monitor ×48 h for total thyroidectomy.¹
- DrainRemove when <50 ml/24 h.¹
- AirwayObserve overnight; emergent decompression for hematoma.¹
- VoiceAssess for hoarseness; laryngoscopy if persistent.¹
References
- Panieri E, Fagan J. Thyroidectomy. In: Open Access Atlas of Otolaryngology, Head & Neck Operative Surgery. University of Cape Town; 2023.