Endocrine—Hyperthyroidism
Concept
Multiple etiologies, surgery only for very specific indica- tions. Important to now how to make diagnosis, the vari- ous treatment options, when to treat with surgery, and how to treat hyperthyroid crisis.
Way Question May be Asked?
“27 y/o female referred to your office by a family practi- tioner with the recent diagnosis of hyperthyroidism. What do you want to do?” May have symptoms of hyperthy- roidism and you need to make diagnosis first: tachycardia, heat intolerance, weight loss, fatigue, palpitations.
How to Answer?
Always a complete H+P
History
Anxiety Tremulousness Weight loss Sweating Heat intolerance Palpitations
Physical Exam
Neck nodules Exophthalmoses
DDx
Grave’s disease (most common) Toxic Multi-nodular goiter
Hyperfunctioning adenoma Malignancy
Subacute thyroiditis
Factitious thyrotoxicosis (exogenous T4)
Ovarian (struma ovarii thyroid tissue in ovarian ter- atoma), testicular, pituitary tumors (rarest)
Laboratory tests
TSH Free T4
LATS level (Grave’s disease!) Thyroid antibody (thyroiditis) Thyroid Scan (r/o “hot” nodule) U/S neck (r/o mass)
Management
(1) Medication (not for pts with toxic nodules)
(a) PTU or Tapazole—problem is compliance and complications of medications including agranulocytosis
(b) Can use PTU in pregnant pt (2) Radioactive iodine I 131
(a) Good option in older pts
(b) Single dose usually effective in Grave’s disease and cause hypothyroidism in > 50% pts (c) Repeat doses possible
(3) Surgery
(a) Lobectomy or subtotal thyroidectomy for toxic nodules
(b) Subtotal thyroidectomy appropriate for:
cosmesis
pregnant pt in second trimester who fails PTU failure of medical treatment after 1–2 years compressive symptoms
hyperthyroidism in children
young women who want to become pregnant 41 Part 1.qxd 10/19/05 2:51 AM Page 41
thyrocardiac pts
pts with severe exophthalmos (c) Need to prepare pt for surgery:
PTU until surgery
Beta blockers prn (if use, continue in post-op period!)
Lugol’s solution (iodine) 2cc BID starting 10–14 days prior to surgery to decrease vascularity of thyroid gland
Continue beta blocker post-op for 8–10 days (t 1/2 of hormone)
(d) Thyroxin for life post-op (can’t tell true thyroid status until 1–2 years post-op
Thyroid Storm—Life-Threatening
Initiated by physiologic stresses (surgery, anesthesia, MI, infection, childbirth)
Presentation of: fever, tachycardia, abdominal symp- toms, change mental status
Mortality ~10%
Treatment:
IVF Sedatives O2
Cooling blankets PTU 250 mg q 4 h Hydrocortisone 100 q 6 h
Beta blockers (may need IV inderal for control cardiac arrhythmias)
May need intubation Treat precipitating cause!
Common Curveballs
There will be a hot nodule
Will have post-op complication of:
Laryngeal nerve injury Hematoma
Hypothyroidism, hypoparathyroidism
Injury to external branch of superior laryngeal nerve Recurrent hyperthyroidism
Pt will be pregnant
Pt will fail medical therapy
Asked to describe subtotal thryoidectomy (leave 3–5 gm tissue behind)
Ask how to prepare pt prior to surgery
Pt will have nodule that will be a malignancy (changing scenarios) on U/S, FNA, or final pathology
Pt will develop thyroid storm
Strikeouts
Not making correct diagnosis
Not knowing how to treat hyperthyroidism Not knowing indications for surgery
Not knowing how to treat/recognize thyroid storm Not ruling out adenoma/malignancy
Not checking LATS/thyroid U/S, T4/TSH
Not being comfortable with discussion of complica- tions of thyroidectomy
Not knowing when to do partial v. total thyroidectomy
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