Clinical Diagnostics - Electrolytes

Front 1

These two terms can be used interchangeably.

Back 1

Plasma and Serum

Front 2

The plasma electrolytes are often included as part of a chemistry or metabolic panel. These panelts are known as?

Back 2

Chem-7, Chem-10, Chem-23

Front 3

Where do the plasma electrolytes fall in the Chem 7 chart?

Back 3

Na Cl BUN
GLu

K HCO3 CR

Front 4

What are the three typical things that you can add to this?

Back 4

Ca, Mg, PO4

Front 5

What consists of the basic metabolic panel?

Back 5

Chem 7 plus Ca

Front 6

What are the units of measurement for plasma electrolytes in the US

Back 6

mEq/L, mg/dL

Front 7

Plasma osmolality is a measure of?

Back 7

Plasma Concentration

Front 8

What determines plasma osmolality, this ion also is the most prevalent?

Back 8

Na

Front 9

Plasma osmolality is largely determined by __, and regulated through _____ and ___.

Back 9

Na
Thirst
ADH

Front 10

Under normal circumstances ____ plasma osmolality (or ______) stimulate pituitary to release ___ (producing more concentrated urine) and produces thirst.

Back 10

High
Hypotension
ADH

Front 11

____ plasma osmolality suppresses ADH release, leading to ______ of more free water (resulting in dilute urine)

Back 11

Low
Excretion

Front 12

What is the normal range for plasma osmolality?

Back 12

Normal 275-290

Front 13

If the plasma osmolality is above 290 what results?

Back 13

Thirst, release ADH

Front 14

If the plasma osmolality is below 275 what results?

Back 14

ADH suppressed

Front 15

What is a measure of urine concentration?

Back 15

Urine Osmolality

Front 16

What is the urine osmolality norm in the absence of ADH?

Back 16

50-100 mosmol/kg

Front 17

What is the urine osmolality norm with the peak ADH effect?

Back 17

900-1200 mosmol/kg

Front 18

This ion is the major determinant of both plasma osmolality and effective circulating volume.

Back 18

Sodium, Na

Front 19

What is the normal plasma level for sodium?

Back 19

136-144 mEg/L

Front 20

A sodium level of 145 or higher is?

Back 20

Hypernatremia

Front 21

A sodium level of 135 or lower is what?

Back 21

Hyponatremia

Front 22

Urine sodium can be used to estimate what?

Back 22

Volume status

Front 23

What is the numbers for a normal spot urine?

Back 23

> 25

Front 24

What usually indicates hypovolemia?

Back 24

A urine sodium of < 25.

Front 25

FENa stands for?

Back 25

Fractional Excretion of Sodium

Front 26

FENa is used to measure?

Back 26

ratio of quantity of sodium filtered to that excreted, directly evaluating renal sodium handling.

Front 27

FENa can give a more accurate assessment of volume status than UNa in a patient with?

Back 27

Acute renal failure

Front 28

What is usually the cause of hypernatremia?

Back 28

A lack of access to water, Sodium load, Free Water Depletion.

Front 29

In hypernatremia, the plasma osmolality is _______ ?

Back 29

Increased

Front 30

If urine osmolality is over 700-800 mosmol/kg, then ___-_____ ____ is functioning ______.

Back 30

ADH-Renal axis
normally

Front 31

If ADH is either not present or nonfunctional as in ______ ______ then you can't reabsorb free water, and urine becomes dilute meaning the urine osmolality is less than?

Back 31

Diabetes Insipidus
100

Front 32

In order to distinguish central from nephrogenic DI you have to give what?

Back 32

ddAVP = ADH

Front 33

Central DI is a ____ problem.

Back 33

Pituitary

Front 34

If it is nephrogenic DI then it is a ?

Back 34

Kidney problem

Front 35

If urine osmolality is 300-800 mosm/kg then the cause of hypernatremia could be either ____ __ or _____ _____.

Back 35

Partial DI
Osmotic Diuresis

Front 36

How can Partial DI or Osmotic diuresis be differentiated?

Back 36

By total solute excretion = urine osmolality x daily urine volume

Front 37

How do you know if total solute excretion is elevated.

Back 37

It will be over 1000

Front 38

In most cases of hyponatremia, _____ _____ is reduced. Due to the fact that _____ _______ is primarily determined by sodium.

Back 38

Plasma Osmolality
Plasma Osmolality

Front 39

In some cases of hyponatremia plasma osmolality may be normal or elevated ___________.

Back 39

Pseudohyponatremia

Front 40

What can pseudohyponatremia be due to?

Back 40

Hyperproteinemia, Hyperlipidemia, or Hyperglycemia

Front 41

If pseudohyponatremia is due to hyperglycemia, then it can be corrected by adding ___ mEq/L to sodium for each ___ mg/dL rise in glucose above ___.

Back 41

1.6
100
100

Front 42

Example: How would you correct a sodium of 132 mEq/L if the patient had a glucose of 400 mg/dL

Back 42

1.6 x 3 = 4.8

Add 4.8 to patients 132 mEq/L Na

Corrected Na = 136.8

Front 43

In most cases of hyponatremia, plasma osmolality is ____?

Back 43

Low

Front 44

If it is unclear whether patient is hypovolemic or euvolemic a _____ ______ may help.

Back 44

Urine Sodium

Front 45

Urine Na < __ mEq/L : _______

Back 45

25
Hypovolemic

Front 46

Urine Na > __ mEq/L : ________

Back 46

40
Euvolemic

Front 47

If urine Na is between 25-40 give isotonic saline. If _______, then fluids remove stimulus for ADH release, leading to more dilute urine and normalization of the serum sodium. If _____, then urine osmolality remains high, while Na excretion is promoted by volume expansion

Back 47

Hypovolemic
SIADH

Front 48

What is represented by Euvolemic hyponatremia, with low plasma osmolality, an inappropriately high urine osmolality (>100), and a urine Na of > 40 mEq/L?

Back 48

SAIDH

Front 49

What is normal plasma potassium?

Back 49

3.5 - 5.0 mEq/L

Front 50

Greater than 5 mEq/L Potassium is?

Back 50

Hyperkalemia

Front 51

Less than 3.5 mEq/L of Potassium is?

Back 51

Hypokalemia

Front 52

Potassium secretion is directly linked to ______ reabsorption. Under influence of _______ and ________ ________.

Back 52

Sodium
Aldosterone
Natriuretic Peptides

Front 53

Renal potassium handling is also linked to renal handling of ______ ion and _______. This system is activated by ______, which stimulates production of K/H-ATPase

Back 53

Hydrogen
Chloride
Hypokalemia

Front 54

What is the normal response to Hypokalemia?

Back 54

Lower K excretion to below 25-30 mEq per day or 15 mEq/L

Front 55

Hyperkalemia is when you have a plasma potassium of ?

Back 55

>5mEq/L

Front 56

A normal response to hyperkalemia is stimulation of _______ release, which increases potassium excretion in the urine.

Back 56

Aldosterone

Front 57

In the presence of potassium load, normal renal excretion should exceed __-___ mEq/day.

Back 57

80-100mEq/day

Front 58

What are the two main causes of hyperkalemia?

Back 58

Potassium load or decreased excretion.

Front 59

K Load = increased intake of _.
IV or PO (Salt Substitute)
K Release from cells:
Insulin deficiency, hyperglycemia, and hyperosmolality.
Metabolic acidosis
Increased Catabolism, Exercise
Beta-blockers, Digitalis, Succinylcholine

Back 59

K

Front 60

Hypoaldosteronism, Renal Failure, Effective Circulating Volume Depletion can all lead to?

Back 60

Impaired Excretion of K

Front 61

Hyperkalemia due to decreased renal excretion can be demonstrated by a decreased ______ potassium.

Back 61

Urinary

Front 62

The normal response to hyperkalemia is increased _______ release, leading to increased renal K _______ and a TTKG > 10. A low value particularly if <__, is highly suggestive of __________.

Back 62

Aldosterone
excretion
5
hypoaldosteronism

Front 63

What is the normal range for Chloride?

Back 63

88-106 mEq/L

Front 64

What is the normal number for HCO3?

Back 64

24 mEq/L

Front 65

What is a measure of calcium that includes both free and albumin bound calcium?

Back 65

Plasma Calcium

Front 66

What is the normal range for the plasma calcium?

Back 66

8.8-10.3 mg/dL

Front 67

What is a normal albumin level?

Back 67

4.5

Front 68

How do you correct low calcium when you have low albumin.

Back 68

For every 1.0 you are below 4.5 with albumin, you add 0.8 to measured calcium. Example = Ca 7.2, Albumin 2.5. . . . correct 2.0 X .8 = 1.6. . . .1.6 +7.2 = 8.8 = normal calcium level.

Front 69

This measurement of calcium takes into account only the free form, or the physiologically active calcium.

Back 69

Ionized Calcium

Front 70

What is the normal range for ionized calcium?

Back 70

4.5-5.5 mg/DL in aduls

Front 71

This hormone is secreted by the parathyroid glands and is stimulated by ________ or suppressed by ________.

Back 71

Parathyroid Hormone
Hypocalcemia
Hypercalcemia

Front 72

This hormone increases bone resorption, releasing calcium and phosphate into plasma. Increases calcitrol, active form of Vit. D, formation, Increases renal calcium reabsorption, and increases renal phosphate excretion.

Back 72

Parathyroid Hormone

Front 73

Vitamin D is found in ____, made in ____. Travels to _____ and is converted into _______. Then travels to kidneys and is converted into _____.

Back 73

Diet
Skin
Liver
Calcidiol
Calcitrol

Front 74

Normal response to hypocalcemia is increased release of ______, which then leads to increased ______.

Back 74

PTH
Calcitrol

Front 75

If hypocalcemia is detected, first confirm by repeat measurement of _____ ______.

Back 75

Ionized calcium

Front 76

If still hypocalcemic, after doing a repeat measurement of ionized calcium, then first check an ____ ___.

Back 76

Intact PTH

Front 77

This can only be interpreted correctly when measured simultaneously with serum calcium?

Back 77

Intact PTH in Hypocalcemia.

Front 78

A low, or even normal, value in the presence of hypocalcemia is strong evidence for _________. This is due to the fact that hypocalcemia should stimulate an ______ in ___.

Back 78

Hypoparathyroidism
Increase
PTH

Front 79

This can be elevated in patients with kidney disease, vitamin D deficiency, or pseudohypoparathyroidism.

Back 79

Intact PTH in Hypocalcemia

Front 80

Intact PTH measurements in hypocalcemia are typically _____ or decreased in patients with ________.

Back 80

Normal
Hypomagnesemia

Front 81

Hypomagnesemia is seen when values are < ___ mEq/L, this induces ____ resisitance.

Back 81

< 0.8mEq/L
PTH

Front 82

If _____ ______ is elevated then combination is virtually diagnostic of hypoparathyroidism or pseudohypoparathyroidism.

Back 82

Serum Phosphate

Front 83

If serum phosphate is low, then either secondary ________ or low ____ intake is the cause. If secondary hypoparathyroidism, then renal excretion of phosphate will be _____. If low dietary intake, then renal excretion of photphate will be ___.

Back 83

Hypoparathyroidism
Dietary
Elevated
Low

Front 84

Vitamin D studies in hypocalcemia:

_____ will be low in presence of vitamin D deficiency.

______ will be high in presence of vitamin D deficiency.

Back 84

Calcidiol

Calcitriol

Front 85

Hypercalcemia is a calcium level of > ___ mg/dL.

Back 85

> 10.5mg/dL

Front 86

Hypercalcemia is most commonly caused by?

Back 86

Primary hyperparathyroidism or malignancy (values may go above 13 mg/dL).

Front 87

If elevated or normal, then primary hyperparathyroidism is the cause of hypercalcemia?

Back 87

Intact PTH

Front 88

If intact PTH is suppressed in a patient with hypercalcemia, you have to check _____ and ____ _ _____.

Back 88

PTHrp
Vitamin D Studies

Front 89

This can be produced by the tumor, acts at a PTH receptor, resultin normal peripheral actions of PTH, and thus mediating "humoral hypercalcemia of malignancy"

Back 89

PTHrp in Hypercalcemia

Front 90

Vitamin D metabolites in hypercalcemia:

Elevated ______: Vitamin D Intoxication.

Elevated ______: Ingestion of calcitriol, extra renal production of calcitriol, increased renal production of calcitriol.

Back 90

Calcidiol
Calcitriol

Front 91

If PTH, PTHrp and vitamin D studies are unremarkable in hypercalcemia testing, then what other tests should be considered. (5 things)

Back 91

Serum Phosphate
Urinary Calcium
Multiple Myeloma
Hyperthyroidism
Vitamin A Intoxication

Front 92

Serum phosphate in hypercalcemia will be low in what two cases?

Back 92

Hyperparathyroidism
Humoral hypercalcemia of malignancy

Front 93

What cases is serum phosphate in hypercalcemia elevated?

Back 93

Granulomatous disease
Vitamin D intoxication
Milk-Alkali syndrome
Bone Resorption

Front 94

Urinary calcium in hypercalcemia is _______ in thiazide diuretic use, milk alkalai syndrome, or familial hypocaliuric hypercalcemia.

Back 94

Decreased

Front 95

Urinary calcium in hypercalcemia is ____, _____ or _____ in hyperparathyroidism or hypercalcemia of malignancy.

Back 95

High, normal or increased