6. Fluid and Hemodynamics Flashcards Preview

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Flashcards in 6. Fluid and Hemodynamics Deck (32):
1

What is generally the major determinant of osmolality?

Sodium (you can basically double Na + 10) - glucose sometimes but in general it's mostly sodium

2

Which osmole freely moves from ECF to ICF?

Urea

3

Do sodium and glucose move freely from ECF to ICF?

No - limited to the ECF component

4

What happens to the brain in hypo vs. hypernatremia?

Mental status changes (hyponatremia - swelling of cells, hypernatremia - shrinking of cells)

5

Why is there essentially no glucose, fructose, or galactose in cells?

Gets metabolized instantly

6

What happens to serum sodium when you have hyperglycemia?

Hyponatremia because water leaves cells - dilution effect

7

When we lose isotonic fluid, where does it come from?

ECF

8

When do we get isotonic loss of fluid?

Hemorrhage, diarrhea

9

When do we get isotonic gain of fluid?

Too much saline

10

What is it called when we lose more salt than water?

Loss of hypertonic solution (e.g. when we use diuretics)

11

What is the most common cause of gaining pure water without salt?

SIADH

12

What cancer has SIADH as a paraneoplastic syndrome?

Small cell lung cancer

13

What is the treatment of choice for SIADH?

Free water restriction because you're constantly absorbing pure water

14

When ADH is present do you concentrate or dilute your urine?

Concentrate

15

Serum sodium < 120 - be suspicious of?

SIADH

16

What diabetic medications produce SIADH?

Oral sulfonylureas

17

What compartment is all the total body sodium in?

ECF

18

What clinical sign always accompanies increase in total body sodium?

Pitting edema (because of the increase in sodium in interstitial fluid)

19

What do you call it when we lose pure water?

Diabetes insipidus

20

What should you give an infant with diarrhea?

Hypotonic salt solution because they have hypotonic diarrhea

21

Sodium has to be combined with what to be absorbed in the GI for oral replacement?

Glucose because of cotransport

22

What is the tonicity of sweat?

Hypotonic salt solution

23

What is the sympathetic response to hypovolemia (decreased cardiac output)?

Catecholamines!

1. Venoconstriction - increase return to the right side of the heart
2. Increase HR and contractility
3. Upregulate RAA axis - increase aldosterone to reabsorb salt and water

24

Where are the receptors that sense blood flow in the kidney?

JGA in afferent arteriole

25

What do you give in hypovolemic shock if you don't have blood?

ISOTONIC saline - you need to keep the fluid in ECF (normal saline is basically plasma without the protein)

26

What is the tonicity of the fluid you absorb in the PCT?

Roughly isotonic

27

What is the tonicity of the fluid you absorb via aldosterone?

Roughly isotonic

28

What is the tonicity of the fluid you absorb via ADH?

Pure water (hypotonic)

29

What does ANP do?

Gets rid of salt - only released in volume overloaded states (when right or left atria are dilated)

30

What is the ADH level in central diabetes insipidus?

Low

31

What does skin turgor tell you?

Total body sodium (normal if skin snaps back)

32

What's your nonpharmacologic treatment for any pitting edema state?

Restrict salt and water