Chapter 26 (Lecture) Flashcards
1
Q
if the cause of the imbalance is respiratory, often what will try to compensate
A
kidneys
2
Q
if the cause of imbalance is metabolic, what will try to compensate
A
respiratory system
3
Q
- breathing is imparied so PCO2 levels are high and blood pH is low
- if the kidneys are trying to compensate, HCO3- levels will also elevate
A
respiratory alkalosis
4
Q
- breathing rate is increased - PCO2 levels will be lower and pH will be higher
- if the kidneys are trying to compensate HCO3- levels will begin to fall
A
respiratory alkalosis
5
Q
- the is a renal problem-blood pH is lower and blood HCO3- levels are lowered
- respiratory systems compensates by increasing the increasing the rate and depth of breathing–so PCO2 levels go down below normal
A
metabolic acidosis
6
Q
- there is a renal problem–blood pH is higher and blood HCO3- levels are elevated
- respiratory systems compensates by decreasing the rate and depth of breathing–so PCO2 levels go up and pH levels go down
A
metabolic alkalosis
7
Q
- caused by any condition that impairs gas exchange, also shallow breathing can cause it
- most common cause of acidosis
- PCO2 increases and pH decreases
A
respiratory acidosis
8
Q
- hyperventilation, tumor affecting respiratory center
- CO2 is washed out of the body too quickly
- PCO2 decreases and pH increases
A
respiratory alkalosis
9
Q
- severe diarrhea, renal failure, starvation, excessive alcohol intake
- low blood pH and low blood HCO3- levels
- not caused by CO2 fluctuations
A
metabolic acidosis
10
Q
- vomiting or suctioning of acidic gastric contents, excessive bicarbonate intake
- increasing blood pH and increasing HCO3- levels
A
metabolic alkalosis
11
Q
normal pH range of plasma
A
7.35-7.45
12
Q
normal range of PCO2 in plasma
A
35-45 mmHg
13
Q
normal range of HCO3- in plasma
A
22-26 mEq/L
14
Q
- the ultimate acid-base regulatory system
- slowest action, but it is the only system that can get rid of acids generated by metabolism (phosphoric, lactic, ketoic acids)
- kidneys can also conserve and generate new bicarbonate ions as needed
A
renal regulation
15
Q
increased H+ leads to increased CO2 levels and to
A
increased respiration
16
Q
buffer types
A
- physiological (respiratory and renal)
- chemical
17
Q
- 1-2 times stronger than chemical buffers
- acts more slowly than chemical buffers
- works with CO2 levels
- increased H+ leads to increased CO2 levels and to increased respiration
A
respiratory regulation
18
Q
- intracellular proteins are the most powerful ICF buffers in the body
- can bind or release H+ when necessary
A
protein buffer system
19
Q
- does the same as a bicarbonate buffer, but works more in the nephron than in the plasma
- has a more powerful effect on the ICF and nephron
A
phosphate buffer system
NaH2PO4
20
Q
- converts strong acids and bases into weak acids and bases
- primary buffer in the ECF
A
bicarbonate buffer system
H2CO3
21
Q
- one or two molecule systems that resist changes in pH
- bind H+ if pH drops
- release H+ is pH rises
A
chemical buffers
22
Q
types of chemical buffers
A
- bicarbonate
- phosphate
- protein
23
Q
dissociate completely in solution and greatly affect pH
A
strong acids
ex: HCl
24
Q
partially dissociate and act as buffers
A
weak acids
ex: H2CO3
25
whenever pH drops below 7.35
acidosis
26
fluid inside of cells, makes up about 40% or 25L of body weight
intracellular compartment
27
whenever pH rises above 7.45
alkalosis
28
decreased calcium ions in plasma
hypocalcemia
29
causes of hypocalcemia
nutritional, vitamin D deficiencies, burns
30
symptoms of hypocalcemia
* neuromuscular excitability
* tetany
* depressed excitability of the heart
31
increased calcium ions in the plasma
hypercalcemia
32
causes of hypercalcemia
hyperparathyroidism, too much vitamin D
33
symptoms of hypercalcemia
* bone wasting
* fractures
* kidney stones
* cardiac arrhythmias
* depressed respiration
34
total body water =
40L or roughly 60% of total body weight
35
all fluid outside of cells, makes about 20% or 15L of body
extracellular compartment
36
subcompartments within the extracellular fluid
* interstitial fluid
* plasma
* lymph
* CSF
* synovial fluid
37
* different than extracellular composition due to the presence of selectively permeable cell membrane
* most proteins, larger molecules remain in the intracellular fluid
* water moves in and out via osmosis
intracellular compartment composition
38
* fluid and electrolyte intake must equal output by kidneys, liver, and lungs
* substances such as RBC, albumins stay in the blood vessels
extracellular compartment composition
39
water intake should = ....... each day
water ouput
40
average daily water intake/output should equal
2500ml/day
41
water is obtained through
* 60% drinking
* 30% moist food
* 10% internal metabolic pathways
42
water is lost through
* urine = 60%
* feces = 4%
* sweat = 8%
* skin diffusion and lung evaporation (heat) = 28%
43
calcium levels are regulated by which hormone majorly
parathyroid hormone
| smaller extent calcitonin
44
decreased blood calcium =
increased PTH secretion; raises blood calcium
45
PTH targets
bone, kidneys, GI tract
46
increased blood calcium =
decreased calcitonin; lowers blood Ca
47
increased K+ ions in plasma
hyperkalemia
48
causes of hyperkalemia
decreased aldosterone, cell rupture due to burns or other trauma
49
symptoms of hyperkalemia
* restlessness
* neuromuscular irritability followed by fatigue due to overexcitement, which leads to muscular weakness and flaccid paralysis
50
decreased K+ ions in plasma
hypokalemia
51
causes of hypokalemia
too much aldosterone, reduced intake, GI tract problems
52
weak acids that can accept H+ ions if the pH is too acidic, or can release H+ ions if the pH is too alkaline
buffers
53
symptoms of hypokalemia
causes hyperpolarization, leads to muscle weakness and mental confusion
54
decreased ECF K+ =
hyperpolarization of cell membranes
55
increased ECF K+ =
depolarization of cell membranes
56
major ICF cation
K+
57
what does the ICF-ECF concentration of K+ affect
membrane permeability
58
what are exchanged between the compartments
water, nutrients, gas
59
mEq/L
measures of electrical charges per liter
60
Fluid in both the ICF and ECF have a concentration of about
290-300 mOsm
## Footnote
.9%
61
concentration (osmolality) is due to which factors
* amount of solutes present
* amount of water present
62
increasing the number of solutes will do what to the concentration
increase
63
increasing the amount of water will do what to the concentration
lower it
64
pushes fluid into ICF from ECF
hydrostatic pressure
65
draws fluid from ICF into ECF
osmotic (oncotic) pressure
66
the more solutes a solution has, the ______ its osmotic pressure
greater
67
how can you raise osmolality of ECF
* losing water
* ingesting excess electrolytes
68
1. excessive water loss of H2O from ECF
2. ECF osmotic pressure rises
3. cells lose H2O to ECF by osmosis; cells shrink
dehydration
69
1. excessive H2O enters the ECF
2. ECF osmotic pressure falls
3. H2O moves into cells by osmosis; cells swell
hypotonic hydration
70
disorders of water imbalance
* dehydration
* hypotonic hydration
71
results from fluid in the interstitial space
edema
72
major ECF electrolyte
Na+
73
maintained mainly by aldosterone
Na+ homeostasis
74
too much Na+ in the plasma =
dehydration
75
too little Na+ in the plasma =
edema
76
causes of hypernatremia
* too much aldosterone
* hypertonic saline solutions
* dehydration
77
symptoms of hypernatremia
* CNS dehydration leads to confusion and lethargy
* neuromuscular irritability with twitching and convulsions
78
causes of hyponatremia
* vomiting
* diarrha
* burns
* dilution
* increased diuresis
* aldosterone deficiency
79
volume = 40 L, 60% body weight
total body water
80
volume = 25 L, 40% body weight
intracelluular fluid (ICF)
81
volume = 12 L, 80% of ECF
interstitial fluid (IF)
82
volume = 3L, 20% of ECF
plasma
83
what triggers the thirst mechanism
increased osmolality, decreased plasma volume
84
in the hypothalamus near the third ventricle
thirst center
85
causes the sensation of thirst, causes dry mouth
osmoreceptor over activity
86
quenches thirst
drinking
87
inhibits osmoreceptors
drinking, activation of stretch receptors in SI and stomach
88
typical sodium ion value
142 mEq/L
89
typical potassium value
3.7 mEq/L
90
typical calcium value
5 mEq/L
91
causes of edema
* incompetent venous valves
* hypoproteinemia
* liver disease
92
what would occur if there was an increase in plasma osmolality
* thirst
* release of ADH
* concentrated urine
93
what type of tissue is least hydrated
adipose tissue
94
water lost through expired air
insensible water loss
95
promotes net osmosis into tissue cells, causing them to swell as they become abnormally hydrated
hyponatremia
96
diuresis peaks how long after drinking water
one hour
97
what type of individual would have the most body water
infant
98
acts on the kidneys to decrease water excretion
ADH
99
when water output exceeds intake over a period of time
dehydration
100
most water is excreted via
kidneys
101
associated with the swelling of cells
hypotonic hydration
102
least abundant positive electrolyte in ECF
magnesium
103
common stimuli of ADH
* increased ECF osmolality
* decreased BP
* reduced blood volume
* stimulation of baroreceptors
104
what hormone increases sodium excretion
progesterone
105
aldosterone targets what area of the kidney
kidney tubules
106
most important factor that incluences K+ secretion
K+ concentration in ECF
107
what process is most affected by calcium levels
neuromuscular excitability
108
a condition that results from solute loss, water retention, or both
hyponatremia
109
enhances release of calcium from bone
parathyroid hormone
110
what happens when the concentration of Na+ decreases in the ascending limb of the nephron
aldosterone levels increase
111
electrolyte balance in the body usually refers to the balance of
salts
112
most abundant negative electrolyte in ECF
chloride
113
in addison's disease, the adrenal cortex produces too little aldosterone, and so Na+ is lost. people with this disorder often crave
salty foods
114
most important force causing net outward water flow across capillary walls
hydrostatic pressure of capillary blood
115
