hypo/hypernatremia

Question 1

osmolality

Answer 1

concentration of particles in a solution

Question 2

tonicity

Answer 2

osmotic agents that cannot freely cross the cell membrane will result in water movement into or out of the cell

Question 3

serum osmolarity formula

Answer 3

2[Na] + BUN /2.8 + glucose/18

Question 4

hyponatremia serum sodium

Answer 4

<135 mEq/L

Question 5

hyponatremia is due to

Answer 5

increased free water

Question 6

appropriate response to hyponatremia should be ______ urine

Answer 6

dilute

Question 7

appropriate response to hypernatremia should be ______ urine

Answer 7

concentrated

Question 8

pseudohyponatremia

Answer 8

lab error due to hyperproteinemia or hypertriglyceridemia altering the plasma water concentration

isotonic

Question 9

isotonic hyponatremia

Answer 9

low measured serum Na and normal serum osmolarity

Question 10

hypotonic hyponatremia has ____serum Na and ____ serum osmolarity

Answer 10

low

low

Question 11

hypertonic hyponatremia has ____serum Na and ____ serum osmolarity

Answer 11

low
high

(translocational hyponatremia)

Question 12

translocational hyponatremia

Answer 12

reflects a movement of water from ICF to ECF due to hyperglycemia
(hypertonic hyponatremia)

Question 13

after determining serum osmolarity, what is the next step in determining the cause of hyponatremia?

Answer 13

determine the patient’s volume status

Question 14

the type of hyponatremia is determined by ____ and _____

Answer 14

serum osmolarity

volume status

Question 15

clinically significant/true hyponatremia

Answer 15

hypotonic hyponatremia

Question 16

hypotonic hyponatremia pathophys

Answer 16

excess of water compared to sodium in the ECF due to either dilution or depletion

Question 17

hypovolemic hypotonic hyponatremia has ____ ECF volume

Answer 17

low

Question 18

euvolemic hypotonic hyponatremia has ____ ECF volume

Answer 18

normal

Question 19

hypervolemic hypotonic hyponatremia has ____ ECF volume

Answer 19

high

Question 20

renal causes of hypovolemic hypotonic hyponatremia

Answer 20

diuretics

mineralocorticoid deficiency

Question 21

extrarenal causes of hypovolemic hypotonic hyponatremia

Answer 21

diarrhea
vomiting
burns
fever
bleeding

Question 22

renal causes of euvolemic hypotonic hyponatremia

Answer 22

SIADH
post-op
stress
drugs
glucocorticoid deficiency
polydipsia
tea and toast/beer potomania

Question 23

tea and toast/beer potomania

Answer 23

reduced solute intake in the setting of normal or elevated free water intake

Question 24

renal causes of hypervolemic hypotonic hyponatremia

Answer 24

acute or chronic kidney injury with low urine output

Question 25

extrarenal causes of hypervolemic hypotonic hyponatremia

Answer 25

CHF cirrhosis nephrotic syndrome

Question 26

urinary sodium concentration due to renal losses

Answer 26

>20 mmol/L

Question 27

urinary sodium concentration due to extra renal causes

Answer 27

< 20 mmol/L

Question 28

hypovolemic hypotonic hyponatremia treatment

Answer 28

volume replacement with normal saline

Question 29

euvolemic hypotonic hyponatremia treatment

Answer 29

water restriction

Question 30

hypervolemic hypotonic hyponatremia treatment

Answer 30

volume removal with diuretics or water and Na restriction

Question 31

most common cause of hyponatremia in hospitalized pts

Answer 31

SIADH

Question 32

causes of SIADH

Answer 32

drugs CNS lesions pulmonary lesions

Question 33

treatment for hyponatremia without symptoms

Answer 33

limit water intake to 1-1.5 L / day`

Question 34

hypervolemia symptoms

Answer 34

peripheral and presacral edema pulmonary edema JVD HTN

Question 35

hypovolemia symptoms

Answer 35

poor skin turgor dry mucous membranes flat neck veins hypotension

Question 36

severe hyponatremia treatment

Answer 36

for Na <115 | IV hypertonic saline

Question 37

general clinical features of hyponatremia

Answer 37

``` confusion lethargy fatigue N/V cramps ```

Question 38

symptoms of severe hyponatremia

Answer 38

*develops acutely seizures coma respiratory failure

Question 39

what is osmotic demyelination

Answer 39

damage to the myelin sheath due to a rapid correction of hyponatremia, typically involves the pons region

Question 40

how much should sodium be raised per hour

Answer 40

0.5 mEq/L

Question 41

possible severe sx of demyelination

Answer 41

nerve palsies quadriplegia locked in syndrome

Question 42

hypernatremia definition based on sodium

Answer 42

increased serum sodium >145 mEq/L

Question 43

hypernatremia is due to (general)

Answer 43

increased free water loss | hypertonic sodium gain

Question 44

hypernatremia serum osmolality is always ______

Answer 44

increased resulting in a hypertonic state

Question 45

in hypovolemic hypernatremia Na is ____ and ECF is _____

Answer 45

high | low

Question 46

in euvolemic hypernatremia Na is ____ and ECF is _____

Answer 46

high | normal

Question 47

in hypervolemic hypernatremia Na is ____ and ECF is _____

Answer 47

high | high

Question 48

renal causes of hypovolemic hypernatremia

Answer 48

diuretics postobstruction intrinsic renal disease

Question 49

when the cause of volume change is renal the serum Na is _____

Answer 49

>20 mmol

Question 50

extrarenal causes of hypovolemic hypernatremia

Answer 50

excess sweating diarrhea burns fistulas

Question 51

renal causes of euvolemic hypernatremia

Answer 51

diabetes insipidus | hypodipsia

Question 52

renal causes of euvolemic hypernatremia

Answer 52

lack of access to/intake of water leads to oliguria

Question 53

renal causes of hypervolemic hypernatremia

Answer 53

primary hyperaldosteronism | Cushings

Question 54

hypernatremia symptoms

Answer 54

``` dehydration on PE thirst confusion lethargy muscle twitching vomiting ```

Question 55

severe hypernatremia sx

Answer 55

seizures coma neuro defects respiratory arrest

Question 56

diabetes insipidus is due to

Answer 56

decreased or inefficient ADH = polyuria

Question 57

when the cause of volume change is renal, the urinary Na is _____

Answer 57

<600 mOsm/kg

Question 58

hypervolemic hypernatremia treatment

Answer 58

loop diuretics and free water replacement so that hypernatremia does not get worse

Question 59

hypovolemic hypernatremia treatment

Answer 59

isotonic fluids to replete volume and then hypotonic fluids (D5W) to correct hypernatremia

Question 60

diabetes insipidus treatment

Answer 60

desmopressin (synthetic ADH)

Question 61

urine osmolality is ___ if extra renal loss , and urine is ___

Answer 61

increased, concentrated

Question 62

urine osmolality is ___ if renal loss , and urine is ___

Answer 62

decreased | dilute

Question 63

pure water and 5% dextrose in water are both

Answer 63

hypotonic fluids