CABS-Thyroid Storm Flashcards
why is temperature increased during thyroid storm
due to hypermetabolic state and excess heat being generated
what can cause thyroid storm
illness, stress
score of _____ is highly suggestive of thyroid storm
> /= 45
Why cold saline in Rx for thyroid storm?
to reduce hyperthermia
Why NOT propranolol in a patient with asthma when treating thyroid storm?
exacerbate asthma
(its a non-selective B1 and B2 blocker)
Why use IODINE for thyroid storm Rx?
leads to selective feedback inhibition due to overexpression of iodine in the gland
Why NOT iodine before PTU/ METHIMAZOLE to treat thyroid storm?
Need to inhibit thyroid peroxidase with PTU first, otherwise iodine will be more available to be used as a substrate for T3/T4
Why NOT AMIODARONE for arrhythmia during thyroid storm?
contains 40% iodine
Why hypercortisolemia in thyroid storm?
increased stress leading to increased production of ACTH
Why hyperglycemia in thyroid storm?
insulin release is impaired and cortisol is increased causing increase in blood glucose
Why hypercalcemia in thyroid storm?
increased osteoclastic function—-> bone resorption—-> hypercalcemia
enzyme used to convert T4 to T3 in peripheral tissues
deiodinase
inhibits T4 and T3 synthesis
Methimazole and PTU
blocks T4 and T3 release
SSKI
Lugol’s Iodine
block hormone action
beta blockers
block peripheral conversion of T4 to T3
PTU
glucocorticoids
propranolol
blocks proteolysis of thyroglobulin to T3 and T4 in follicular cell
Iodides
blocks organification and coupling by iodine and thyroid peroxidase
Iodides
Thioamides
inhibits thyroid peroxidase (blocks iodide formation and tyrosine iodination)
Methimazole and PTU
10 times more potent than PTU and is drug of choice for thyroid storm
Methimazole
_____ causes these 2 things if given in 1st trimester of pregnancy
Aplasia cutis = absence of scalp skin
Choanal atresia = of posterior nasal cavity, leaves a membrane
Methimazole
has a transient effect
reduces vascularity
inhibits proteolysis of thyroglobulin and disrupts organification of iodine
Iodine/Iodide
lid lag
lid retraction
tachycardia
thyrotoxicosis from any cause
exophthalmos, chemosis, periorbital edema, ophthalmoplegia, pretibial myxedema
thyrotoxicosis specific for Grave’s disease
IGF-1R blocker
IGF-1R overexpressed in orbital fibroblasts and immune cells
Used when corticosteroids/ radiation fails or in severe cases
TEPROTUMUMAB
Thyrotoxicosis –> increase the expression and activation of _______receptors –> more blood pumping (high output HF) so it appears to compensate for the heart failure
B1
Exacerbation of already existing CHF (history of high output cardiac failure); both pulmonary and systemic congestion/CO variable
acute decompensated heart failure
_______ increases abundance of beta1 receptors in heart and also increases sensitivity of these receptors to Epi and NE
Heart beats faster and increases inotropy (contractile strength) and eventually gets tired and fails
increase metabolism and metabolic demands of tissues– imposes demands on heart (increases CO to supply and remove metabolic products form tissues)
T3 and T4
why is there a dilated IVC (>2.1 diameter)
IVC dilated due to increased back pressure due to pump failure
other causes for high output heart failure
thyrotoxicosis, beriberi, and anemia
impairs heart muscles ability to produce energy due to lack of thiamine
thiamine deficiency (beriberi)
tachycardia because O2 supply/demand mismatch –> HF
anemia
polyneuropathy, symmetric muscle wasting
deficiency in vitamin B1
dry beriberi
high output cardiac failure (due to systemic vasodilation); vitamin B1 deficiency
wet beriberi
pulmonary edema developing in very short period of time due to severe acute decompensation of HF
flash pulmonary edema
to treat flash pulmonary edema
furosemide
nitrates
The pituitary glycoprotein hormones FSH, LH, TSH, and hCG have common ___ subunits
α
______ also acts on TSHR, leading to gestational thyrotoxicosis
hCG
Anti-TSHR antibody diffusion into placenta → neonatal ______
thyrotoxicosis
mostly stimulating TSHR, but can be blocking. Graves and other autoimmune diseases
anti-TSHR (TSH receptor)
present in more than 85% of patients with Hashimoto thyroiditis and in more than 30% of patients with Graves disease
antithyroglobulin
All patients with Hashimoto thyroiditis, in about 85% of patients with Graves disease, and in some patients with other autoimmune diseases like type 1 DM, celiac disease, and Addison disease
anti-thyroid peroxidase (anti-TPO)
I-_____ is for imaging
I-123
I-____ used for radioactive ablation of thyroid gland
I-131
___nodule = carcinoma
cold
no uptake
Indicates a non-functioning tumor and thus is unlikely to be an adenoma
cold nodule
generalized low uptake
thyroiditis
generalized high uptake (diffuse)
Grave’s
Single hot spot on uptake
toxic adenoma
multiple hot spots on uptake
toxic multinodular
Lid retraction/lag in ___
thyrotoxicosis
Ptosis in ____
myasthenia gravis
Enophthalmos in ___
Homer
Proptosis (Exophthalmos) in _____
Graves
____hormones ↑ permeability of membranes and ↑ expression of Na-K-ATPase and Ca2+-ATPase
Increased activity of ATPases → Release of some energy as heat.
thyroid
hormone also increases uncoupler protein expression (UCP1/2)
thyroid
Class III K-channel blocker antiarrhythmic drug; has 37% iodine
causes thyrotoxicosis and pulmonary fibrosis
Amiodarone
e
c
e
b
d
