Brainscape's Knowledge GenomeTM

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


See full index

N935 Pathophysiology > Parathyroid Gland > Flashcards

Parathyroid Gland Flashcards

1
Q

How many parathyroid glands are there?

A

4

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

What do the parathyroid glands produce?

A

parathyroid hormone

parathormone

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

How is parathormone managed?

A

dependent on plasma calcium concentration

released into the blood stream by negative feedback mechanism

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

What is the half life of parathyroid hormone?

A

4 minutes

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

What is the average parathyroid hormone level?

A

8-51pg/mL

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

What is released in responses to hypocalcemia?

A

release parathyroid hormone

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

What is released in response to hypercalcemia?

A

releases calcitonin

suppression of both synthesis and release

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

What does parathyroid hormone regulate?

A

a normal calcium concentration

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

What are the three interfaces that calcium affects?

A

GI tract
bone
renal tubules

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

How is calcium utilized in the GI tract?

A

when the body has low calcium, parathyroid hormone increases calcium absorption from the food we ingest and phosphate reabsoprtion to increase serum levels of calcium and phoshphat

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

What is the purpose of calcium in bones?

A

Calcium is absorbed in the bones for bone strength

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

Reabsorption

A

in regards to physiology:

absorption into the circulation

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

What are the four processes that occur when serum calcium is low and sensed by the parathyroid gland?

A
  1. Calcium is reabsorbed into the blood stream via bones
    a. Bone reabsorption: absorption into circular in bones
    Osteoclast break down bone tissue and release minerals in bones and release into blood stream
    1. Calcium is reabsorbed from kidney after being reabsorbed in blood stream in exchange for calcium
    2. Also, in the kidney vitamin D is activated and travels to the intestine where parathyroid hormone and vitamin D increases the absorption of active transport of calcium and phosphate to get reabsorbed into the blood stream
    3. Kidney: Calcium is coming from kidneys after being excreted and being reabsorbed into blood stream in exchange for phosphate phosphorus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are osteoclasts?

A

cells found on the surface of bones and are multi-nucleated cells that contain numerous mitochondria and lysosomes

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

What is calcitonin

A

opposes the effect of PTH

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

Where is calcitonin secreted?

A

parafollicular cells of the thyroid

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

When is calcitonin secreted?

A

increased serum calcium (hypercalcemia)

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

What are the three ways calcitonin lowers blood calcium?

A

inhibits osteoclasts activity in bones (promotes bone storage of calcium)
inhibits renal tubular cell reabsorption of Ca2+
inhibits Ca2+ absorption in the intestines

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

What is the role of vitamin D?

A

fat soluble molecule that increases the intestinal absorption of calcium, magnesium and phosphate

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

What two types of Vitamin D come from our diet?

A 
vitamin D2 (cholecalciferol)
vitamin D3 (ergocalciferol)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the synthesis of vitamin d2 dependent on?

A

sun exposure

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

Where are both vitamin d forms hydrolyzed and form?

A

in the liver

25-hydroxyvitamin

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

What happens to 25-hydroxyvitamin in the kidney?

A

metabolized again into 1,25 hydroxyvitamin D

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

Where are vitamin D receptors in the body?

A

intestines, kidneys, bone, parathyroid gland

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

What is the role of vitamin D in the body?

A

calcium homeostasis and metabolism
helps transport proteins absorb calcium in the intestine
bone reabsorption
reabsorption of calcium in the distal nephron

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

What is the calcium lab value important to us?

A

ionized calcium

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

What is the normal total serum calcium concentration

A

9.5-10.5mg/dL

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

What is a normal ionized calcium?

A

4.75-5.7mg/dL

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

What calcium is free and unbound?

A

ionized calcium

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

What compromises bound calcium?

A

calcium that is bound to protein (albumin)

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

How of calcium is bound to albumin

A

50%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

How much calcium is ionized?

A

40%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

How much calcium is bound to chelating agents?

A

10%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What are examples of chelating agents?

A

phosphate
citrate
sulfate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What happens to serum calcium in acidosis?

A

increase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What happens to serum calcium in alkalosis?

A

decrease

37
Q

What does ionized calcium fraction depend on ?

A

pH

38
Q

What decreases as pH decreases?

A

protein binding decreases as pH decreases

39
Q

Describe protein binding and ionized fraction of calcium in alkalosis?

A

increased protein binding decrease ionized fraction of calcium

40
Q

Describe protein binding and ionized fraction of calcium in acidosis?

A

decrease calcium binding to protein

increased ionized fraction

41
Q

For each 0.01 decrease in pH, ionized calcium…

A

increases by 0.05mmol/L

42
Q

Where is total calcium of the body stored?

A

99% in the bone

1% in the ECF and ICF

43
Q

What is the purpose of calcium in the bone ?

A

bone formation

reservoir for ECF (Ca2+)

44
Q

What is the role of calcium in the extracellular fluid?

A

blood clotting

excitability of nerve and muscle

45
Q

What is the role of calcium in the ICF?

A

metabolic regulation for action of hormones and enzyme activitation

46
Q

What are disorders related to PTH?

A

reduced production
impaired PTH due to peripheral resistance
parathyroid gland adenomas

47
Q

What are diseases of reduction production of PTH

A

digeorge syndrome
catch 22 syndrome
autoimmune

48
Q

What is hyperparathyroidism?

A

excess production of PTH

49
Q

What is the most common cause of hyperparathyroidism

A

hypercalcemia

50
Q

What defines hypercalcemia?

A

total serum calcium above 10.4mg/dL

51
Q

How is hyperparathyroid classified?

A

primary
secondary
ectopic

52
Q

What is primary hyperparathyoridism?

A

parathyroid gland destruction

excess secretion of parathromone

53
Q

What is secondary hyperparathyroidism?

A

appropriate response to hypocalcemia as seen in CKD

54
Q

what can cause primary hyperparathyroidism?

A

benign adenoma
hyperplasia
carcinoma

55
Q

What are majority of the primary hyperparathyroidism cases?

A

benign adenoma (80-90%)

56
Q

How many primary hyperparathyroidisms are asymptommatic?

A

50%

57
Q

What are the manifestations of primary hyperparathyroidism

A

manifestations of hypercalcemia in the kidney and skeletal sytem
calcium deposits in renal parenchyma or recurrent nephrolithiasis and skeletal pathology

58
Q

What calcium levels do primary hyperparathyroidism symptoms present?

A

11.5-12mg/dL

59
Q

What are neuromuscular S/S in primary hyperparathyroidism?

A

skeletal muscle weakness

60
Q

What are renal S/S in primary hyperparathyroidism?

A

polyuria
polydipsia
decreased GFR
kidney stones

61
Q

What are hemoatopoietic S/S in primary hyperparathyroidism?

A

anemia

62
Q

What are cardiac S/S in primary hyperparathyroidism?

A

prolonged PR interval
shortened QT interval
systemic hypertension

63
Q

What are gastrointestinal S/S in primary hyperparathyroidism?

A

vomiting
abdominal pain
peptic ulcer
pancreaitis

64
Q

What are skeletal S/S in primary hyperparathyroidism?

A

skeletal demineralization
collapse of vertebral bodies
pathologic fractures

65
Q

What are nervous S/S in primary hyperparathyroidism?

A

somnolence
decreased pain sensation
psychosis

66
Q

What are ocular S/S in primary hyperparathyroidism?

A

calcifications (band keratopathy)

conjunctivitis

67
Q

How do you diagnosis hyperparathyroidism?

A 
PTH assay
calcium levels
vitamin D levels
renal levels
CT scans
68
Q

What are medical management practices for hyperparathyroidism with mild hypercalcemia (12mg/dl)?

A

hydration

69
Q

What are medical management practices for hyperparathyroidism with moderate to severe hypercalcemia (13-15mg/dl)?

A

IV saline hydration and furosemide to promote Na/Ca diuresis

70
Q

What are surgical management implications for hyperparathyroidism?

A

definitive treatment
intraoperative PTH assay is measured before and at 5 minute intervals after adenoma removal to confirm a rapid fall to normal

71
Q

What must occur with multiple-gland hyperplasia?

A

all glands must be identified and either:
all three removed with partial excision of the fourht (leaving good blood supply)
total parathyroidectomy with immediate transplantation of a removed, minced parathyroid gland into the forearm muscles

72
Q

What is hypoparathyroidism?

A

absence or deficiency in PTH secretion
resistance of peripheral tissues to the effects of the hormone
iatrogenic (removed surgically with thyroidectomy)

73
Q

What does hypoparathyroidism result in?

A

hypocalcemia

74
Q

What are causes of hypoparathyroidism?

A 
decreased or absent parathyroid hormone
accidental removal of parathyroid glands during thyroidectomy
parathyroidectomy to treat  hyperplasia
idiopathic (Digeorge)
resistance of peripheral tissues to effects of parathyroid hormone
congenital
pseudohypoparathyroidism
acquired
hypomagnsemia
chronic renal failure
malabsorption
anticonvulsant therapy (phenytoin)
osteoblastic metatases
acute pancreatitis
75
Q

What are signs of hypocalcemia?

A 
neuronal irritability
skeletal muscle spasms
tetany
seizures
fatigue and mental status
prolonged QT interval
congestive heart failure
hypotension
76
Q

What are symptoms of acute hypocalcemia?

A

stridor
laryngospasm
apnea

77
Q

How does tetany occur?

A

normally calcium blocks sodium channels and inhibits depolarization of nerve and muscle fibers
reduced calcium lowers the threshold for depolarization
hypocalcemia

78
Q

What is the treatment for hypocalcemia?

A

electrolyte replacement
calcium and vitamin D
hypomagnesia (oral and IV replacement)

79
Q

What is the treatment for severe and symptomatic hypocalemia?

A

10-20ml of 10% calcium gluconate or 3-5 ml of 10% calcium chloride followed by a continous infusion of calcium (1-2mg/kg/h)

80
Q

Do you want to treat hypocalcemia prior to surgery?

A

yes

81
Q

What the major anesthetic risks with hypocalcemia?

A

decreased cardiac contractility and dysrhythmias
tetany
altered response to muscle relaxants
risk for laryngospasm

82
Q

What will result without treatment to an overactive parathyroid gland?

A

fatigue, bad memory, kidney stones and ostopporosis

83
Q

Whta does a parathyroid gland tumor cause?

A

hyperparathyroidism

84
Q

What is the most common amount of over active parathyroid glands?

A

single 70%
two/three 25%
all four 5%
<1% cancer of parathyroid

85
Q

Anesthetic management during parathyroidectomy

A

concern for cardiac dysrhythmias secondary to elevated calcium
NIMS ETT (assess RLN)
effects of NMR are unpredictable s/c to hypercalcemia (consider qualitative NMB monitoring)
careful positioning (risk fo fractures)

86
Q

What are post-operative complications to parathyroidectomy?

A 
similar to thyroid surgery
RLN injury
hematoma
hypocalcemia
acute hypocalcemia (only if severe deficit preop or injury to all parathyroid glands)
87
Q

Intraoperative implications for parathyroid surgery

A 
supine 
arms tucked
gel head ring
ether screen adn 2 clicks down on bed for neck extension
2 PIVs
antiemetic coverage
GA with NIMs ETT (videocope)
inhalation agent
remifentanil infusion
no antibiotics
88
Q

What is neccessary for parathyroid surgery?

A

large IV for PTH sampling
NBP cuff can be used as tourniquet with stopcock inserted between 6inch connector tubing and IV tubing
can use arterial line
Saph IV

89
Q

Describe PTH sampling during surgery

A

baseline PTH sample
scheduled PTH samples in or at:
time 0 (at removal of parathyroid as alerted by surgeon)
time 5, 10, 14 min post parathyroid removal

N935 Pathophysiology (6 decks)

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