Brainscape's Knowledge GenomeTM

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


See full index

Clinical Chemistry > Module 3- Electrolytes > Flashcards

Module 3- Electrolytes Flashcards

1
Q

What are the functions of electrolytes?

A

Maintenance of osmotic pressure, water balance, pH, enzyme cofactors/activators
Regulation of heart and muscle

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

What should you avoid when collecting electrolytes?

A

Hemolysis
Proper anticoagulant (not K3EDTA tubes)
Separation from cells (increases K)
K can increase after exercise or clenching fist

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

What are electrolytes?

A

Molecules that dissociate into charged ions

In lab, we refer to:
Na, K, Cl, HCO3

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

How is water distributed?

A

Intracellular - 70%

Extracellular - 30%

  • plasma 20%
  • interstital fluid 80%
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is concentrated state vs. diluted state?

A

Concentrated - hypernatremia, hyperosmolality, hypovolemia- needs more water

Diluted - hyponatremia, hyposomolality, hypervolemia - need less water

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

What is ADH?

A

Released from posterior pituitary in response to high osmolality. Acts on kidney tubules to increase water reabsorption.

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

What is aldosterone?

A

Released from the adrenal gland in response to low sodium/osmolality. Acts on kidney tubules to increase reabsorption of sodium.

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

What is sodium and how it is regulated?

A

Extracellular
Role in plasma osmolality and water balance
Reabsorbed in tubules

Regulated by aldosterone

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

What is potassium? How is it regulated?

A

Intracellular
Reabsorbed in proximal tubules
Regulates cell membrane potential

Regulated by aldosterone (reabsorption of Na means secretion of K)

Levels affected by dehydration, acidosis, alkalosis, and cellular breakdown

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

What is chloride? What is anion gap?

A

Extracellular
Reabsorbed by tubules passively
Maintains electroneutrality

Anion gap= cations - anions
Ref range: 5-15 mmol/L
Ref range with K: 10-20 mmol/L
Gap is due to anions present in sample that are not measured

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

What does it indicate when anion gap is increased? Decreased? Negative?

A

Increased - displacement of Cl-
Decreased - rare
Negative - indicates a issue, check sample and repeat

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

What is bicarbonate?

A

The form most CO2 is transported in the plasma

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

What is magnesium?

A

Intracellular
Functions in enzyme activation, nerve conductivity, neuromuscular contraction, formation of bones and teeth

Ionized form in plasma is the active form
Regulated by PTH

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

What is calcium? How is it regulated?

A 
99% bones and teeth
In plasma: 
- 50% free ionized active form
- 45% protein bound
- 5% in complexes

Regulated by PTH (if levels are low) and calcitonin (if levels are high)

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

What does it indicate if calcium levels are high? Low?

A

High - hypercalcemia, Muscle weakness, cardiac arrhythmias

Low - hypocalcemia, increased muscle excitability. May be low with high protein levels and high pH levels

Calcium and phosphate levels tend to act inversely

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

What is the role of calcium?

A

Enzyme activation
Muscle contraction
Membrane permeability
Cell motility

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

What is phosphorus and how is it regulated?

A

Intracellular
Most contained in bone

Regulated by PTH, Vit D, and GH

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

What is fluid depletion?

A 
Caused by:
Excessive vomiting
Decreased water intake
Polyuria
High temperature

Dehydration - blood has increased Na, increased plasma osmolality, increased Hct, increased urea
Urine has decreased volume

19
Q

What is diabetes insipidus?

A

Decreased ADH, causes less water to be absorbed in kidney tubules
Failure to concentrate urine
Urine will have low specific gravity and no glucose

20
Q

What is fluid excess?

A

Homeostatic imbalance
increased intake
Increased ADH
Can lead to edema (build up of fluid causing swelling)

21
Q

Sodium disorders - hypernatremia

A

Decreased plasma water
Increased plasma sodium
Dehydration
Hyperaldosteroneism

22
Q

Sodium disorders - hyponatremia

A

Inappropriate ADH secretion

Hypoaldosteronism Addison’s disease

23
Q

What is the electrolyte exclusion effect?

A

Pseudo hyponatremia
Hyperlipidemia - excess solids reduces the plasma component in blood
(Electrolytes only dissolved in the plasma)
There is a decrease in ALL electrolyte levels when using indirect methods

24
Q

Potassium disorders - hyperkalemia

A

Caused by crush injuries, trauma
Metabolic acidosis - decreased pH, plasma K increases

Hypoaldosteronism/Addison’s disease - decreased aldosterone, less K excreted

25
Q

Potassium disorders - hypokalemia

A

Hyperaldosteronism - increased K excretion

Metabolic alkalosis
Prolonged vomiting or diarrhea

26
Q

Chloride disorders - hypochloremia

A

Displacement by other anions

Associated with Na losses

27
Q

Chloride disorders - hyperchloremia

A

Dehydration
Increased salt intake
Decreased bicarbonate levels

28
Q

What is sweat chloride?

A

Aids in the diagnosis of cystic fibrosis
Autosomal recessive trait of sweat gland excretion
Sweat chloride will be markedly elevated

29
Q

Magnesium disorders - hypermagnesemia

A

From administration of magnesium containing products

Renal failure

30
Q

Magnesium disorders - hypomagnesemia

A

Prolonged vomiting or diarrhea

Malnutrition

31
Q

Calcium disorders - hypercalcemia

A

Hyperparathyroidism
Malignancies
Excessive vitamin D
Multiple myeloma

32
Q

Calcium disorders - hypocalcemia

A

Hypoparathyroidism
Protein loss
Chronic hypomagnesemia

33
Q

Phosphorous disorders - hyperphosphatemia

A

Acute or chronic renal failure
Increased intake
Lymphoblastic leukemias

34
Q

Phosphorous disorders - hypophosphatemia

A

Hyperparathyroidism

Long term total parenteral nutrition

35
Q

Sodium analysis:

A

Ion selective electrode - glass membrane

Interference from hemolysis, lipid/proteinemia

36
Q

What is the reference range for sodium?

A

Serum/plasma 135-150 mmol/L

37
Q

Potassium analysis:

A

Ion selective electrode - valinomycin electrode

Interference from: hemolysis, time on cells, lipid/proteinemia

38
Q

What is the reference range for potassium?

A

Serum/plasma: 3.5-5.0 mmol/L

39
Q

Chloride analysis:

A

Coulometric titration - silver ions present in excess which causes a change in conductivity

ISE - silver chloride/silver sulphide membrane electrode

Mercuric thiocyanate (photometrically) 480nm

Interference from bromide and lipid/proteinemia

40
Q

What is the reference range for chloride?

A

Serum/plasma 98-108 mmol/L

41
Q

Bicarbonate analysis:

A

ISE - silicone rubber membrane with pH electrode

Ref range 22-30 mmol/L

42
Q

Magnesium analysis:

A

Spectrophotometric

Interference from hemolysis, time in cells, tourniquet use, EDTA citrate or oxalate anticoagulants

Ref range 0.65-1.05 mmol/L

43
Q

Calcium analysis:

A

Spectrophotometric
ISE from ionized Ca

Interference from EDTA, citrate or oxalate anticoagulants, patient position, time on cells, ionized calcium should be tested immediately

Ref ranges
Total calcium 2.10-2.60 mmol/L, CL 3.25
Ionized calcium 1.15-1.35 mmol/L, CL 1.50

44
Q

Phosphorous analysis:

A

Spectrophotometric

Interference from hemolysis, time in cells, EDTA oxalate or citrate anticoagulants

Ref ranges 0.80-1.50 mmol/L

Clinical Chemistry (2 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions