Tony Tuan H. Nguyen, MD
June 8, 2010
Post-Thyroidectomy Considerations
Indications: FNA findings of definite/suspicious/inconclusive for malignancy; goiter; thyroid cancer
(papillary, follicular, medullary, anaplastic); thyroid nodule; hyperthyroidism; Grave's disease
Cancer (50%):
papillary (80%); follicular (10%); medullary (5%); anaplastic (1%); lymphoma (1%)
Benign lesions (50%):
nontoxic goiter (20%); thyrotoxicosis (10%); thyroiditis (5%); benign nodules (5%); other (10%)
Demographics:
15-80yo, Male:Female 1:8
Routine Procedure:
Time: 1-2 hours.
Blood loss: 50-70ml
Postop Considerations:
Hypoparathyroidism (↓ Ca+ +): 3–5%
- Presents 24-48 hours postop.
- Trousseau's sign: Inflate blood pressure cuff. After 3 minutes, you will get carpopedal
spasms
- Chvostek's sign: Tap on facial nerve and you will elicit facial nerve spasms
- Acute Mild Symtoms: fatigue, hyperirritability, anxiety, depression peri-oral numbness,
paresthesias of the hands and feet, muscle cramps)
- Acute Severe Symptoms: carpopedal spasm, laryngospasm, and focal or generalized
seizures, generalized tonic muscle contractions secondary to severe tetany (<4.3 mg/dL), no
neuromuscular symptoms.
- Hypotension, EKG changes (prolonged QT, U waves, flat or inverted T waves)
Hematoma: 1–2%
- Airway compromise: immediate drainage and/or reintubation
Thyroid storm (usually in association with Graves' disease)
- Life-threatening exacerbation of hyperthyroidism occurring during periods of stress
- Hyperthermia (> 40°C), tachycardia, widened pulse pressure, anxiety, altered mental state
→ psychosis → coma, and myopathy (rhabdomyolysis in 50%; severe in 4%).
- Mistaken for malignant hyperthermia, sepsis, anaphylaxis, neuroleptic malignant syndrome.
- Treatment: oxygen, fluid, electrolyte correction, cooling blankets, acetaminophen.
o Propylthiouracil to block synthesis by blocking thyroid peroxidase and iodinase
o Methimazole to block thyroid peroxidase
o Sodium iodide to block release by negative feedback on anterior pituitary to inhibit
release of TSH and thyroid hormone (give after PTU, otherwise you may get iodine
escape)
o Steroids (hydrocortisone or dexamethasone) to block peripheral conversion
o ß-blockers (propranolol) to block peripheral effects and peripheral conversion
Wound infection: 0.2–0.5%
Recurrent laryngeal nerve damage
Unilateral (hoarseness): 0.77%
Bilateral (aphonia, respiratory obstruction): 0.39%
Vagus
-
-
Superior laryngeal nerve
o external branch – motor to the cricothyroid muscles (tenses vocal cords for high pitch
sound)
o internal branch – sensory to the interior of the larynx to the level of the subglottic
space
Recurrent laryngeal nerve – motor to all muscles of larynx (except cricothyroid) sensory to
subglottic area
**All intrinsic muscles of the larynx are innervated by the recurrent laryngeal nerve of CN X
except cricothyroid which is innervated by the superior laryngeal nerve
Recurrent laryngeal nerve (Unilateral) injury to leads to hoarsenss.
Recurrent laryngeal nerve (Bilateral) injury leads to unopposed cricothyroid muscles -> airway
obstruction
Superior laryngeal nerve injury leads to hoarseness and presdisposes to aspiration