Thyroid and Parathyroid Disorders
Hypo- and hyperthyroidism, crises, and thyroid surgery
| Hypothyroidism (e.g., Hashimoto's) | Hyperthyroidism (e.g., Graves') | |
|---|---|---|
| Signs | Fatigue, cold intolerance, weight gain, constipation, dry skin, hair loss, bradycardia, slow thinking, depression, heavy periods | Anxiety, heat intolerance, weight loss, diarrhea, tachycardia/A-fib, tremor, insomnia, goiter; Graves': bulging eyes (exophthalmos) |
| Labs (primary disease) | TSH high, free T4 low | TSH low, free T4/T3 high |
| Treatment | Levothyroxine (empty stomach, lifelong; start low in older and cardiac patients) | Methimazole (PTU in 1st trimester), beta blockers, radioactive iodine, surgery |
| Crisis | Myxedema coma: hypothermia, bradycardia, hypotension, hypoventilation, low Na⁺ and glucose, coma → IV levothyroxine, steroids, ventilation, passive warming; avoid sedatives | Thyroid storm: high fever, severe tachycardia, delirium, vomiting → beta blocker, PTU or methimazole, then iodine, steroids, cooling with acetaminophen (not aspirin) |
After thyroidectomy
- Airway: semi-Fowler's, support the neck; tracheostomy kit, suction and oxygen at the bedside.
- Bleeding: check the dressing and the back of the neck; a tight feeling or swelling = hematoma (airway risk).
- Hypocalcemia (parathyroid injury): tingling around the mouth and fingers, Chvostek's and Trousseau's signs, laryngospasm → IV calcium gluconate at the bedside.
- Voice: ask the patient to speak every few hours. Hoarseness = laryngeal nerve injury.
- Lifelong levothyroxine after total thyroidectomy.
Parathyroid
- Hyperparathyroidism → high calcium: "stones, bones, groans, moans": kidney stones, bone pain and fractures, abdominal pain and constipation, fatigue, depression, confusion. Fluids, avoid thiazides, cinacalcet, surgery.
- Hypoparathyroidism → low calcium: tingling, muscle cramps, tetany, seizures, long QT. Calcium and active vitamin D; IV calcium gluconate for severe symptoms.
Memory hook
Chvostek = cheek (tap the facial nerve → twitch). Trousseau = BP cuff on the arm → hand spasm. Both = low calcium.
Radioactive iodine (for hyperthyroidism)
Not in pregnancy or breastfeeding. For several days: distance from others (especially children and pregnant people), sleep alone, flush twice, separate laundry and utensils, as instructed. Hypothyroidism often follows: lifelong levothyroxine.
Eye care in Graves'
Raise the head of the bed, artificial tears, sunglasses, tape lids if they don't close at night, stop smoking (worsens eye disease).