Fluids & Electrolytes Potter & Perry Ch 41 (Part I)

Front 1

How does h20 supports physiological processes?

Back 1

1. Transports dissolved nutrients & electrolytes, etc
2. Purification of body fluids
3. Maintains electrolytes & fluid balance
4. Maintain BV & fluids

Front 2

How much water are you composed of?

Back 2

60%

Front 3

How many kilograms of water in 1 liter of water?

Back 3

1 kilogram = 2.2 pounds

Front 4

What are differences in TBW based on age/gender?

Back 4

• Newborn – 75-80%
• One year – 67 %
• By adolescence – approaching adult value
• Adult female – 52-55%
• Adult male – 60%
• Older adult - 45-50%

Front 5

How is body fluid distributed?

Back 5

Intracellular
Extracellular

Front 6

How much intracellular fluid (ICF) makes up TBW?

Back 6

2/3 - 40%
Approx 25 - 30L
*Most stable & fairly resistant to major fluid shifts

Front 7

How much extracellular fluid (ECF) makes up TBW?

Back 7

1/3 - 20%
Approx 15L

Front 8

Where is extracellular fluid found?

Back 8

Interstitial fluid - 15%

Intravascular fluid - 5%

Front 9

Where is interstitial fluid found and what does it do?

Back 9

• Outside/between cells and vessels.
• Baths cells
• Reserve fluids - replaces fluid in cell of blood as needed

Front 10

Where is intravascular fluid found?

Back 10

5% (approx 3L)
Found is plasma & lymph
Least stable - losses & gains in response to fluid intake

Front 11

Where is "other" ECF found?

Back 11

1%
Found in: sweat, urine, transcellular fluids.
Fluids in body spaces - CNS, intestinal, synovial fluids, pleural, peritoneal, pericardial, intraocular

Front 12

Force of water pushing against capillary walls is called ______?

Back 12

Hydrostatic pressure

Front 13

Hydrostatic pressure is _____

Back 13

1. Blood pressure
2. Movement of water from area of higher pressure to lower pressure.
3. In cap beds, determines movement of water.

Front 14

What would cause increase in Hydrostatic pressure?

Back 14

Edema

Front 15

What is osmosis?

Back 15

1. Movement of water from lower solute concentration to higher solute concentration.
2. Major force in body fluid movement & IV therapy

Front 16

What is osmotic pressure?

Back 16

• Process of drawing water - hi concentration of solutes has hi drawing power.
• H20 moves until equilibrium has been reached

Front 17

What is osmolality/osmolarity?

Back 17

Concentration of solute in solvent

Front 18

What is the osmolality of plasma?

Back 18

285

Front 19

What is the normal osmolality range?

Back 19

270 - 300

Front 20

What are the major particles in plasma?

Back 20

NEED TO FIND ANSWER - ALBUMIN? CAN'T REMEMBER

Front 21

What is colloidal oncotic pressure?

Back 21

Pulling force exerted by colloid (protein) w/in vascular space

Front 22

This important protein maintains colloidal oncotic pressure ___________.

Back 22

Albumin

Front 23

Do protein molecules typically cross the blood vessel membrane?

Back 23

No, so plasma levels of protein are usually the same.

Front 24

Water movement between plasma & interstitial fluid

Back 24

• Cap hydrostatic pressure (BP)
• Cap oncotic pressure
• Interstitial hydrostatic pressure
• Interstitial oncotic pressure

Front 25

What is capillary hydrostatic pressure

Back 25

Facilitates the outward movement of h20 from the caps to interstitial space

Front 26

What is capillary oncotic pressure?

Back 26

Osmotically attracts h20 from interstitial space back into caps via protein attraction.

Front 27

What is interstitial hydrostatic pressure?

Back 27

Facilitates the inward movement of h20 from interstitial space into caps

Front 28

What is interstitial oncotic pressure?

Back 28

Osmolality attracts h20 from the caps into interstitial space

Front 29

Net filtration - Starling's Law

Back 29

(forces favoring filtration) minus (forces opposing filtration)

Front 30

Forces favoring filtration

Back 30

• Cap hydrostatic pressure (BP)
• Interstitial oncotic pressure (water-pulling)

Front 31

Forces favoring reabsorption

Back 31

• Plasma oncotic pressure (water-pulling)
• Interstitial hydrostatic pressure

Front 32

What differences causes movement?

Back 32

Cap hydrostatic pressure (BP) and cap oncotic pressure

Front 33

Has low pressures, almost the same; has little effect on fluid movement normally

Back 33

Interstitial hydrostatic pressure & interestitial oncotic pressure

Front 34

On which end is hydrostatic pressure greater?

Back 34

Arterial end

Front 35

Where does fluid from oncotic pressure go?

Back 35

It moves from caps to tissues.

Front 36

Where is hydrostatic pressure lower?

Back 36

Venous end

Front 37

Where does fluid from oncotic pressure go?

Back 37

From tissues to caps

Front 38

What is particle movement called?

Back 38

Diffusion

Front 39

Where is sodium greater/lower?

Back 39

Greater - outside cell
Lower - inside cell
*sodium out/potassium in

Front 40

What could result in fluid movement into the interstitial space?

Back 40

Increase in interstitial oncotic pressure

Front 41

What condition would decrease oncotic pressure in the capillaries?

Back 41

Liver failure - due to low protein

Front 42

What is particle movement called?

Back 42

Diffusion

Front 43

Where is sodium greater/lower?

Back 43

Greater - outside cell
Lower - inside cell
*sodium out/potassium in

Front 44

What could result in fluid movement into the interstitial space?

Back 44

Increase in interstitial oncotic pressure

Front 45

What condition would decrease oncotic pressure in the capillaries?

Back 45

Liver failure - due to low protein

Front 46

Directions of particle movement

Back 46

• Free movement of solute (substance or gas) from hi to lo concentration thru semi-permiable membrane
• Most electrolytes, molecules (O2, CO2), move thru cell membrane
• Glucose CANNOT cross membrane w/o insulin *

Front 47

Active transport

Back 47

• Transfer of a substance across a membrane even though the concentration may be higher on the side to which the movement is taking place

• Requires metabolic activity (ATP in Na-K pump)

• Enables large molecules to pass across cell membrane. Allows cell to maintain higher levels of K in the cell & Na outside the cell

Front 48

Third-Spacing

Back 48

• The shift of fluid from the intravascular compartment into a 3rd, or extra space w/in the extracellular compartment, often a body cavity
• Can result in dehydration

Front 49

What is edema?

Back 49

Excessive accumulation of fluid within the interestitial spaces

Front 50

Causes of edema

Back 50

• Increase in capillary hydrostatic pressure
• Decrease in plasma oncotic pressure
• Increase in cap permeability (damage to vessels)
• Lymph obstruction

Front 51

What is ascites & what is the main cause?

Back 51

Excess fluid in the space between the tissues lining the abdomen and abdominal organs (the peritoneal cavity).
• Usually due to severe liver disease
• Due to high BP of liver vessels
• & lo albumin

Front 52

Application - edema

Back 52

• Increased fluids in the interstitial space increase the distance that nutrients & wastes have to move between capillaries & blood

Front 53

Role of hypothalmus in fluid balance

Back 53

• Thirst reflex (osmoreceptors)
• Increased ECF osmolality stimulates osmoreceptors.
• Requires an alert state*
• Stimulated w/ decreased fluid volumes (hypovalemia)
• Increased tonicity (increased Na) of plasma

Front 54

Regulation of Body Fluids *

Back 54

• Increased in plasma osmolality
• Stim of renin-angio-aldosterone mechanism
• Dryness of oralpharngeal membranes

Front 55

What stimulates osmoreceptors?

Back 55

Decrease of fluid volumes & increase of tonicity

Front 56

Hypovolemia is...

Back 56

Decrease of fluid volumes

Front 57

Thirst-Center is stimulated by...

Back 57

• ↑ plasma osmolality
• Stimulation of renin-angiotensin-aldosterone mechanism
• Dryness of oralpharyngeal membranes

Front 58

How does Antidiuretic Hormone (ADH) work?

Back 58

• Osmoreceptors respond to drop in BP or BV ↑ osmolality
• Stimulates pituitary gland to release ADH

Front 59

What does ADH do?

Back 59

• ↑ reabsorption of Na from distal renal tubules
• Decreases urinary output
• Decreases osmolality

Front 60

What do baroceptors do?

Back 60

• In aortic & carotid sinus send signals to pituitary.
• Lowered plasma plasma pressures stimulate release ADH
• Volume-sensitive receptors stim release of ADH to lo circulating volumes

Front 61

Aldosterone

Back 61

• Released from adrenal cortex
• Low ECF sodium (osmolality)
• High ICF (postassium)
• ↑ osmolality of blood
• Conserves sodium
• Increases Na reabsorption
• Regulates Na+ balance in the distal convoluted tubule
• Resulting in h2O balance
• Part of R-A-A-S loop

Front 62

What does conserving sodium do?

Back 62

Causes kidneys to retain Na & excrete K

Front 63

What triggers the release of aldosterone & what is the response?

Back 63

• Drop in BP, BV, or sodium
• Inc reabsorption of Na+, more K is excreted, lowers serum K.
• H2O moves with Na - aldosterone is a volume regulator

Front 64

What inhibits aldosterone?

Back 64

Rise in Na, BP, BV

Front 65

What happens when more Na is excreted in urine?

Back 65

↑ urine output, decrease BV & increased serum K

Front 66

how do natriuretic hormones work?

Back 66

ANP (atria) BNP (ventricles)
• Respond to stretching of atria & ventricles from ↑ BV & pressure
• Opposes renin - angiotensin system
• Decreases renal reabsorption of Na
• Increases urinary excretion of Na & h2o
• Decreases blood pressure and volume

Front 67

B-type Natriuretic hormone

Back 67

• Normal is <100
• Levels are elevated with heart failure.
• Secreted by ventricles in response to excessive stretching of cardiac muscles.

Front 68

ANP

Back 68

Elevated with ↑ right atrial pressure

Front 69

How Antidiuretic Hormones work

Back 69

• Hypothalmus senses low BV/inc serum osmolality & signals the pituitary glands
• Pituitary gland secretes ADH in blood
• ADH causes kidney to retain h20
• h20 retention boosts BV & decreases serum osmolality

Front 70

Aldosterone Production (the steps)

Back 70

• Blood flow to glom drops
• Juxta secrete renin into bloodstream
• Renin travels to liver
• In liver: Renin > angio
• Angio I travels to lungs
• In lungs: angio I > angio II
• Angio II goes to adrenal glands
• Angio II stims adrenal glands to prod aldosterone

Front 71

How Atrial Natriuretic Pepetide works

Back 71

When BV & BP rise & begin to stretch the atria, the heart's ANP shuts off the RAAS (stabilizing BV & BP)

Front 72

Role of kidney on electrolyte balance

Back 72

Regulate Na & K balance
Excretes K in exchange for Na retention

Front 73

Role of lungs & liver on electrolyte balance

Back 73

Regulates Na & h20 balance & BP

Front 74

Role of heart in electrolyte balance

Back 74

Secretes ANP, causing Na extretion

Front 75

Role of sweat glands on electrolyte balance

Back 75

Excrete Na, K, Chloride & h20 in sweat

Front 76

Role of GI tract in electrolyte balance

Back 76

Absorbs & excretes fluids & electrolytes

Front 77

Role of kidney on electrolyte balance

Back 77

Regulate Na & K balance
Excretes K in exchange for Na retention

Front 78

Role of lungs & liver on electrolyte balance

Back 78

Regulates Na & h20 balance & BP

Front 79

Role of heart in electrolyte balance

Back 79

Secretes ANP, causing Na extretion

Front 80

Role of sweat glands on electrolyte balance

Back 80

Excrete Na, K, Chloride & h20 in sweat

Front 81

Role of GI tract in electrolyte balance

Back 81

Absorbs & excretes fluids & electrolytes

Front 82

Role of parathyroid glands on electrolyte balance

Back 82

Secrete parathyroid hormone, which draws calcium into the blood & helps move phosphorous to kidneys for excretion.

Front 83

Role of thyroid gland on electrolyte balance

Back 83

Secretes calcitonin, which prevents calcium release from the bone

Front 84

How do diuretics upset electrolyte balance?

Back 84

• Treats hypertension, heart failure, electrolyte imbalances & kidney disease
• Increase urine prod
• Cause loss of electrolytes, esp K
• Require careful monitoring of electrolytes