Advanced, Clinical - Endocrine/Metabolic, Organ-Based and Clinical Sciences
Major postoperative complications include wound infection, bleeding, airway obstruction (compressing hematoma, tracheomalacia), hypocalcemia, thyroid storm (uncommon, usually associated with Grave’s disease) and recurrent laryngeal nerve injury.
Incidence is 3-5%. Surgery can lead to trauma to the parathyroids, devascularization of the glands with resultant ischemia, or inadvertent excision of these small structures. Hypoparathyroidism with subsequent decreased production of parathyroid hormone leads to decreased serum calcium. Acute hypocalcemia generally presents at 24-48 hours as laryngeal stridor and airway obstruction. First symptoms are usually tingling in the lips and fingertips. Additional findings may develop, including carpopedal spasm, tetany, laryngospasm, seizures, QT prolongation and cardiac arrest. Chvostek’s sign is facial contractions elicited by tapping the facial nerve in the per-auricular area. Trouseau’s sign is carpal spasm on inflation of a blood pressure cuff. CPAP is often effective for associated airway compromise, and 1 gram of calcium gluconate given slowly usually alleviates symptoms.
2) Airway obstruction (compressing hematoma, trachiomalacia)
Incidence of hematoma is 1-2%, tracheomalacia incidence is <1%. Acute airway obstruction from hematoma may occur immediately postoperatively and is the most frequent cause of airway obstruction in the first 24 hours. Definitive therapy is opening the surgical incision to evacuate the hematoma. Re-intubation may be lifesaving for persistent airway obstruction. Consider awake fiberoptic intubation.
3) Recurrent laryngeal nerve injury
Incidence of injury is 0.77% for unilateral damage resulting in hoarseness and 0.39% for bilateral damage with associated aphonia and airway obstruction.
4) Wound infection
Incidence is 0.2-0.5%.
*Airway obstruction: In the first 24 hours is most likely from compressive hematoma. After 24 hours consider laryngeal dysfunction secondary to hypocalcemia.
- Hypocalcemia (3-5%): most common cause of airway obstruction after 24 hours
- Hematoma (1-2%): most common cause of airway obstruction within 24 hours
- Recurrent laryngeal nerve injury (0.77%): usually causes unilateral damage, stridor, hoarseness
- Wound infection (0.2-0.5%)