Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

NURS 804: Pharmacology > Unit 10: Thyroid > Flashcards

Unit 10: Thyroid Flashcards

1
Q

What is the function of the thyroid hormones?

A

metabolic pacemaking

influence/regulate:  
growth
body temperature
energy metabolism
heart rate
cholesterol metabolism
mood
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the difference between total T3 and T4 versus bound T3 and T4?

A

most T3 and T4 are bound to protein and are metabolically inactive
Free T3 and Free T4 are active/not bound

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the name for T3?

A

triiodothyronine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the name for T4?

A

tetraiodothyronine = thyroxine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Which is more potent, T3 or T4?

A

T3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Which is present in higher amounts, T3 or T4?

A

T4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Describe the HPA for the thyroid

A

hypothalamus secretes TRH
TRH stimulates the pituitary to secrete TSH
TSH stimulates the thyroid to secrete T3 and T4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is TRH?

A

thyroid-releasing hormone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is TSH?

A

thyroid-stimulating hormone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the best test for screening for hypo/hyperthyroidism?

A

TSH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the best test for medication adjustment for the thyroid?

A

TSH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How long does it take the TSH to adjust to a new medication level via the body’s negative feedback loop?

A

4-6 weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

TSH is ______ proportional to the amount of active thyroid hormone in the serum

A

INVERSELY

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

If TSH is high, then what?

A

there is not enough circulating thyroid –> hypothyroid

GREAT EXAM QUESTION

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

If TSH is low, then what?

A

there is too much circulating thyroid –> hyperthyroid

GREAT EXAM QUESTION

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Why don’t we check Total T3 and Total T4?

A

Not very important measurements, as we want to know how much T3 and T4 are available

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Why check anti-thyroid antibodies?

A

to determine if hyperthyroidism or hypothyroidism are autoimmune

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Antibody to thyroid peroxidase is what? In what disease is it seen?

A

TPO

Hashimoto’s Thyroiditis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What antibody stimulates the TSH receptor? In what disease is it seen?

A

TRAb

Grave’s Disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the FNA test?

A

completed on a solitary thyroid nodule to rule out malignancy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

True or False: It is common for the thyroid to have nodules

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the Radioactive Uptake Scan, and for what is it used?

A

completed in hyperthyroid patients to identify cause of it

to identify non-active nodule which is likely to be malignant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Why is the FNA test important?

A

identifying thyroid malignancy EARLY is important, as it often metastasizes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What does iodine have to do with the thyroid?

A

required to make thyroid hormones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

How do we make sure we get enough iodine?

A

salt is iodized

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

For what is radioactive iodine used?

A

I-131– destroy the tissue

1.123 – to identify metabolically active nodules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What heart condition does hyperthyroidism commonly cause?

A

A-Fib

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

How is hyperthyroidism treated?

A

medically
radiation
surgery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What foods commonly have iodine?

A

cod

milk

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What medications are used to treat hyperthyroidism?

A

THIODAMIDES:
methimazole (Tapazole)
propylthiouracil (Propyl-Thyracil)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is the drug of choice for hyperthyroidism?

A

methimazole (Tapazole)

32
Q

What is the drug of choice for hyperthyroidism and pregnancy?

A

propylthiouracil (Propyl-Thyracil)

increased protein binding –> less crosses the placenta

33
Q

What can methimazole (Tapazole) cause?

A

elevated liver enzymes

34
Q

What do the thiodamides do?

A

prevent T3/T4 synthesis via 3 mechanisms

35
Q

How long does it take for thiodamide medications to have their effects?

A

3-4 weeks

36
Q

What is a thyrotoxic crisis?

A

extreme hyperthyroidism

37
Q

Methimazole can be hepatotoxic; when should it be discontinued?

A

if transaminases (AST/ALT) are 3x normal

38
Q

AE of methimazole

A 
low prothrombin levels --> bleeding
bone marrow suppression
hepatotoxic
lupus-like syndrome
vasculitis
hypothyroidism
39
Q

Important thing to remember about older thyroid suppression meds:
potassium iodide (SSKI)
potassium iodide-iodine solution (Lugol’s)

A

keep thyroid hormones from being released, so the sudden discontinuation of the meds can cause excessive levels of hormones

40
Q

When are SSKI or Lugol’s solution used?

A

short term pre-operatively before thyroidectomy

thyroid protection during radiation of thyroid

41
Q

What is I-131?

A

Radioactive iodine used for hyperthyroidism and after surgery for some thyroid cancers to get rid of any remaining cancer

42
Q

What normally happens after administration of I-131?

A

thyroid becomes enlarged briefly, but not painful

effect evident 1-2 weeks after administration

43
Q

With what drugs does I-131 interact?

A

other thyroid meds, especially suppressants

amiodarone

44
Q

Why is a low iodine diet recommended with I-131?

A

The thyroid pulls in iodine indiscriminately; we ant it to pull in the radioactive iodine

45
Q

Why should people who receive I-131 be encouraged to drink and void frequently?

A

to release radiation via urine

46
Q

What is I-123?

A

Radioactive sodium iodide used in thyroid scintigraphy

47
Q

What is thyroid scintigraphy?

A

“thyroid uptake scan”
OR
“radionuclide thyroid scan”

where metabolically active nodules take up radioactive iodide; hypo functioning nodules are suggested of malignancy
**if nodules are not making hormones, they will not take up iodine

48
Q

Name other meds used in hyperthyroidism

A

BETA BLOCKERS – for sx control of tachycardia; prevent A-Fib or A-Fib + RVR (propranolol preferred)
CCBs – verapamil (for HR rhythm/rate control)
Cholestyramine (bile acid sequestrant) to bind to T3/T4 in the gut

49
Q

Signs and symptoms of hypothyroidism

A 
weight gain
fatigue
dry skin
cold intolerance
depression
constipation
**slows most things down
50
Q

What is subacute thyroiditis?

A

due to intermittent presence of antibodies, brief periods of hyperthyroidism in early Hashimoto’s

51
Q

Symptomatic treatment of Subacute Thyroiditis

A

Beta blockers
steroids
NSAIDs

52
Q

What is transient thyrotoxicosis?

A

spontaneously resolving hyperthyroidism

53
Q

How is hypothyroidism treated?

A

synthetic replacement:

  • -levothyroxine
  • -levothyronine
  • -liotrix

animal replacement:
–dessicated thyroid

54
Q

What is myxedema?

A

severe hypothyroidism

55
Q

What can result from myxedema?

A

stupor
lethargy
coma

56
Q

What is levothyroxine?

A

T4 that converts to T3

57
Q

Why do we treat hypothyroidism with T4 and not T3?

A

because the half life of T3 is so short

and it is easier to keep a steady level of hormones if we replace T4 (levothyroxine) than T3

58
Q

What is the cause of secondary hypothyroidism?

A

hypopituitary causes

59
Q

What is the cause of tertiary hypothyroidism?

A

hypothalamic causes

60
Q

For treating hypothyroidism, how often should TSH levels be checked?

A

4-8 weeks after starting tx or changing dose
6 months after stable dosing
then every 12 months
anytime there are hypothyroid/hyperthyroid symptoms during treatment

61
Q

What is Tirosint?

A

a soft gel version of levothyroxine that absorbs more quickly and is less affected by coffee and gastric pH

62
Q

What organ is very sensitive to thyroid replacement?

A

the heart

63
Q

What other endocrine dysfunction should be corrected first, before treating hypothyroidism?

A

adrenal insufficiency

64
Q

What can happen for patients with CAD who are also hypothyroid and treated with levothyroxine?

A

arrhythmias

angina

65
Q

What is thyroxine toxicity?

A

too much circulating thyroid hormone

66
Q

Symptoms of thyroid toxicity in children

A

restlessness
insomnia
accelerated bone maturation and growth

67
Q

Symptoms of thyroid toxicity in adults

A 
nervousness
heat intolerance
palpitations
tachycardia
unexplained weight loss
68
Q

Symptoms of long term thyroid toxicity in adults

A

A-fib

increased rate of bone loss in osteoporosis

69
Q

Drugs that increase hepatic microsomal enzymes increase metabolism of what hormones?

A

T3 and T4

70
Q

What needs to happen with thyroid meds if the patient is also on meds that increase hepatic microsomal enzymes?

A

increase dose of thyroid meds

71
Q

What happens with estrogen (dosed and in pregnancy) and thyroid hormones?

A

increases binding of thyroxine and liothyroxine –> so less is available

72
Q

What is desiccated thyroid?

A

thyroxine from an animal source

73
Q

What are the risks of desiccated thyroid?

A

antibody formation

74
Q

What is liothyronine?

A

T3

75
Q

Why don’t we use liothyronine to treat hypothyroidism?

A

harder to make amount of available T3 level/even when using this drug

76
Q

When is thyroid replacement contraindicated?

A

for weight loss when TSH, T3, T4 are normal
abnormal vaginal bleeding
depression
urticaria

77
Q

Risks of thyroid replacement being given when it is not truly needed

A

osteopenia/osteoporosis
A-Fib
CAD/CHF

NURS 804: Pharmacology (42 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions