Brainscape's Knowledge GenomeTM

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


See full index

Renal Week 1 > Disorders of Water Balance > Flashcards

Disorders of Water Balance Flashcards

1
Q

what is the equation to estimate the ICF volume?

A

it is inversely related to the effective osmolality

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

how do we estimate the ECF volume?

A

by physical exam…edema means its up…low BP and high heart rate and less capillary flow mean ECF is down

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

what is the ECF volume usually directly related to?

A

sodium balance

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

what are two situations where ECF volume is not directly related to sodium load?

A

dehydration…still have normal sodium

SIADH

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

when you have a hypotonic hyponatremia situation, what must you look at osmolality or tonicity to check to see if levels are low?

A

osmolality

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

in a hypotonic situation should you have ADH or not?

A

NO want to get rid of water

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

in a hypotonic situation…what should be looked at first to let you know if ADH is there or not?

A

urine osmolality

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

in hypotonic situation…what urine osmolality means you have ADH there? is this normal?

A

urine osmolality above 100

NO

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

in a hypotonic situation…what urine osmolality means ADH is not there? is this normal?

A

less than 100 mOsm

normal

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

after figuring out patient is hypotonic hyponatremic and has urine mOsm over 100…what decision is next?

A

volume status…are they hypovolemic/hyper or euvolemic

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

in a hypotonic hyponatremic state…when you are also hypovolemic…why does ADH function?

A

because hypovolemic means you need fluid and that trumps the hypotonic or natremia problems

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

in a hypotonic hyponatremic hypovolemic state…what will concentration of the urine sodium be? why?

A

it will be less than 20 mEq/L
this is because the RAAS system is activated from the hypovolemic state and leads to aldosterone placing more ENaC channels

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

name three common hypovolemic, hyponatremic hypotonic states

A

burns
diarrhea
vomiting

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

what are three causes of a hypervolemic hyponatremic hypotonic state?

A

CHF, cirrhosis and nephrosis

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

why does a hypervolemic state lead to hyponatremia and hypotonicity?

A

RAAS still activated and so is ADH…so you get lots of water absorption and increased Na absorption but higher rate of water absorption

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

why is RAAS and ADH still working in hypervolemic state?

A

decreased effective arterial blood volume

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

what will the urine sodium concentration be in a hypervolemic hyponatremic hypotonic state?

A

less than 20 mEq/L

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

if patient is euvolemic, hyponatremic, and hypotonic what do we consider as the cause?

A

SIADH

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

what is SIADH?

A

syndrome of inappropriate ADH release

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

in hypovolemic or hypervolemic states with hyponatremia and hypotonicity the urine sodium is low at less than 20 mEq, but the urine is still concentrated…what is causing this?

A

the urea that is still in there… cause ADH doesnt get as much urea out as water

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

why does SIADH lead to high urine conc of sodium?

A

because the RAAS system is not activated

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

name the 6 classes of SIADH causes

A 
pulmonary disorder
exercise
drugs
miscellaneous 
tumors
CNS disorders
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what is the drug to remember that causes SIADH?

A

ecstasy

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

name four miscellaneous causes of SIADH

A 
HIV infection 
pain
post op
nausea
stress
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what is the most common tumor that leads to SIADH?

A

small cell lung cancer

26
Q

what is pseudohyponatremia?

A

when it looks like you have hyponatremia but really you don’t

27
Q

what is the usual cause of pseudohyponatremia?

A

high triglycerides or proteins in the blood

28
Q

will pseudohyponatremia be hypotonic, hyper or iso?

A

isotonic

29
Q

what is the cause of hypertonic hyponatremia?

A

increases serum osmolality from another molecule

30
Q

what is the cutoff between chronic versus acute hyponatremia?

A

acute is less than 48 hours and chronic is longer than 48 hours

31
Q

which is worse and more likely to show symptoms…acute or chronic hyponatremia?

A

acute

32
Q

what do you treat acute hyponatremia with?

A

3%saline

33
Q

how to treat hypovolemic hypotonic hyponatremia?

A

give fluids…isotonic saline

34
Q

how to treat hypervolemic hypotonic hyponatremia?

A

treat cause and restrict fluid and Na+

diuretics

35
Q

name three steps to treat SIADH hypotonic hyponatremia?

A

correct cause
fluid restriction
3%saline

36
Q

what happens if you give way too much sodium too fast to try and correct hyponatremia? what is the name of the syndrome?

A

get high conc of Na in the serum and fluid will rush out of cells..in brain this can be especially problematic

causes osmotic demyelination syndrome

37
Q

what is osmotic demyelination syndrome?

A

when myelin cells degenerate because the hypnatremic state was fixed too rapidly with sodium

38
Q

how high is sodium to classify as hypernatremia?

A

145 mEq/L

39
Q

what are the three changes that can lead to hypernatremia?

A

decreased ECF volume with hypotonic fluid loss
pure water loss but normal ECF volume
increased ECF volume with hypertonic fluid increase

40
Q

give two examples of extra renal ECF volume loss that causes hypernatremia

A

vomit/diarrhea without H2O replacement

41
Q

give two examples of renal losses of ECF volume that can cause hypernatremia

A

osmotic or solute diuresis

diuretics

42
Q

explain how solute diuresis can lead to hypernatremia

A

you have excess solute of something that needs to be secreted and the water follows it out, leaving behind lower water levels with same sodium levels so sodium concentration is high

43
Q

what are the two types of pure water loss that can lead to hypernatremia?

A

renal and extra renal losses

44
Q

give two examples of extra renal pure water loss that can lead to hypernatremia

A

skin and lungs

45
Q

in extra renal water loss with hypernatremia…will osmolality of urine be high or low?

A

high

46
Q

renal loss of pure water leading to hypernatremia is often caused by what?

A

diabetes insipidus

47
Q

in diabetes insipidus…what are the two types? what molecule is affected?

A

central or nephrogenic

ADH

48
Q

with pure water loss from renal issue leading to hypernatremia…will the urine osmolality be high or low?

A

low

49
Q

in hypernatremia with increased ECF volume…what are the two possible causes?

A

increased sodium intake

increased mineralocorticoid

50
Q

what mineralocorticoid increases and causes hypernatremia with increased ECF?

A

aldosterone

51
Q

what will hypernatremia from increased sodium intake lead to in a patient?

A

polyuria…trying to pee off the increased sodium

52
Q

how much urine production to be diagnosed with polyuria?

A

over 3 L a day

53
Q

if you have polyuria and urine osmolality is low…what are the two possible causes?

A

diabetes insipidus

primary polydipsia

54
Q

how do we differ between diabetes insidious and primary polydipsia?

A

diabetes insipidus will have hypernatremia

primary polydipsia will have hyponatremia

55
Q

if you have polyuria with high urine osmolality…what is the cause of the polyuria?

A

osmotic or solute diuresis

56
Q

what is a test to do to determine if patient has diabetes inspidus or primary polydipsia?

A

water deprivation test

57
Q

with water deprivation…how does primary polydipsia urine osmolality change?

A

osmolality will increase to above 600

58
Q

with water deprivation…how does diabetes insipidus urine osmolality change?

A

it stays below 200

59
Q

if you find out you have diabetes insipidus…what can you give to determine if it is central or nephrogenic? what are the results of each?

A

desmopressin

central. ..urine osmolarity increases to 600
nephrogenic. ..urine osmolarity stays low around 200

60
Q

if you give rapid correction of hypernatremia…what can occur?

A

cerebral edema

Renal Week 1 (8 decks)

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