Regulation of thyroid hormones.

Normal: around 20 gm (Contrast: can be as much as 200 gm in Graves) 

TSH goes down before you see an increase in T3, T4. (Lancet Subclinical disease graph)

80 micro of T4 / day. 5 microgram/day : Normal production

Bound to 

THBG (70%)

Pre-albumin (15%) aka Transthyretin

Albumin (15%)

Only 1 % is active form. 

Hyperthryoid 95 % of time, no role of T3. Only about 5 % of hyperthyroid are T3 hyperthyroid. 

T1/2 of 1 week. Hence, no urgency of giving thyroid hormone after surgery unlike adrenectomy. After adrenectomy Hormone replacement has to be quick. 

Antibody.  TSI, TPO, Thyroglobulin ab. 

Clinical Manifestation of Hyperthyroidism: Overt, Subclinical, Apathetic, Storm (or impending storm)

PTU: Only first trimester of pregnancy 

Toxic Hot nodule : RAI treatment ? higher dose than for graves disease? 

HCG mediated 

Prior to surgery: Iodine can be given as it decreases the vascularity

Graves: No longer total thyroidectomy is done. We do partial thyroidectomy. 

Recurrent Laryngeal Nerve damage. Short, non-mobile, bowed. 

Superior laryngeal nerve damage. More difficult to diagnose. 

Additional References: 

Appreciate how hCG causes Hyperthyroidism, and Gynecomastia