Water, Electrolytes, & pH Flashcards Preview

Anatomy & Physiology > Water, Electrolytes, & pH > Flashcards

Flashcards in Water, Electrolytes, & pH Deck (40):
1

What are the two fluid compartments?

1. intracellular 65%
2. extracellular 35%

2

How does water move?

Osmosis

3

What determines water movement?

concentration of solutes in each compartment

4

What are the two sources of water gain?

1. preformed-in food/drink already
2. Metabolic-produced from chemical reaction

5

What are the three sources of water loss?

1. Sensible=observable (urine/feces/sweat)
2. Insensible=unnoticed (through skin and evaporates, not from sweat)
3. Obligatory=unavoidable (expired air/fecal moisture)

6

How is thirst regulated?

osmoreceptors in hypothalmus

7

What is long term inhibition of thirst?

absorption of H20 from small intestine; >than 30 min for change

8

What is short term inhibition of thirst?

cooling and moistening of mouth; satisfies for 30-45 min

9

How is water output regulated?

Kidneys through urine output

10

What is volume depletion (hypovolemia)?

proportionate amounts of H2O and Na+ are lost without replacement

11

What is fluid deficiency?

fluid output exceeds intake over long period of time

12

What is dehydration?

negative water balance-body eliminates more water than sodium

13

Which electrolytes are cations?

Na+
Ca+
K+
H+

14

What electrolytes are anions?

Cl-
HCO3 (bicarbonate)
PO4 3-

15

What is the function of Sodium? ECF

Muscle contraction
Action potential
Rest membrane potential=ATP pump

16

What is the functions of Potassium? ICF

Muscle contraction
Action potential
Rest membrane potential=ATP pump

17

What is the function of Cl-? ECF

HCl
Chloride shift

18

What is the function of Ca+?

bones
2nd messenger
muscle contractions
Blood clots

19

What is the function of Phosphate?

ATP
Nucleic Acids
Phospholipids

20

Why are we constantly producing acid?

Our metabolism

21

What is a buffer?

mechanism that resists changes in pH; releases H+ to maintain pH

22

Which systems act as physiological buffers?

Urinary & Respiratory

23

What are the three major chemical buffers?

1. Bicarbonate
2. Phosphate
3. Protein Systems

24

When would you give normal saline?

Extensive blood loss

25

When would you give potassium chloride?

Patients w/ALKALOSIS w/renal failure; close monitoring of pH

26

When would you give ringers lactate?

Patients with Acidosis

27

When would you give 5% dextrose?

Patients you cannot eat

28

How do kidneys control pH?

they expel H+ from body

29

What is acidosis?

pH

30

What is alkalosis?

pH > 7.45

31

What causes respiratory acidosis (hypoventilation)?

CO2 accumulation (hypercapnia)

32

What causes respiratory alkalosis (hyperventilation)?

CO2 eliminated faster than produced

33

What happens to CO2 and pH during hyperventilation?

CO2 decreases and pH increases

34

What happens to Co2 and pH during hypoventilation?

Co2 increases and pH decreases

35

What causes metabolic acidosis?

excessive diarrhea, ingestion of acidic drugs, diabetes mellitus

36

What causes metabolic acidosis (very rare)?

1. loss of stomach acid
2. overuse of bicarbonates

37

What system compensates for pH imbalances of respiratory origin?

kidneys

38

What system corrects imbalances in the matabolic origin?

respiratory system

39

Does ADH increase urine and salt?

yes

40

What is sodium responsible for?

resting membrane potential