Endocrinology

Question 1

Calcium distribution in body

Answer 1

99% in bones, 1% in fluids and tissue. Of that 1%, 10% bound to phosphate and citrate, 40% bound to protein, and 50% is free. this 50% is ionized calcium

Question 2

causes for hypocalcemia in critically ill patients?

Answer 2

PTH resistance, dec PTH secretion, dec conversion of Vit D in critically ill patients, hypomagnasemia causing PTH resistance

Question 3

reason for hypocalcemia in blood transfusion?

Answer 3

more Ca bound to the citrate in the blood products

Question 4

treatment for thyroid storm?

Answer 4

beta blocker then antithyroid drugs such as PTU or methimazole then 1 hour later iodine solution and steroids

Question 5

how does methimazole work?

Answer 5

blocks thyroid hormone synthesis

Question 6

how does BB work in thyroid storm?

Answer 6

blocks the hyperadrenergic and peripheral effects of thyroid hormone and to some extent blocks conversion of T4->T3

Question 7

How does iodide work in thyroid storm?

Answer 7

decrease release of T4 and T3, give 1 hour after methimazole because if synthesis has not been blocked you can get an increase in hormone activity

Question 8

MOA of steroids in thyroid storm

Answer 8

decrease conversion of T4 to T3

Question 9

euthyroid sick syndrome

Answer 9

low or low normal T4 with low low normal TSH, low T3

Question 10

treatment for acute adrenal insufficiency?

Answer 10

200 mg/d of hydrocortisone given q6h or continuous

Question 11

features of adrenal insuffieciency?

Answer 11

asthenia, pos orthostatics, hypotension, hyponatremia, hypokalemia, normal gap acidosis, random cortisol level <10 micrograms/dL

Question 12

hungry bone syndrome, what is it?

Answer 12

series of postop complications of parathyroidectomy

- acute fall in calcium, mg, K, PO4 due to the loss of high PTH