Renal Physiology I (Exam V) Flashcards
1
Q
What other organ systems are involved in renal physiology?
A
- nervous system
- endocrine system
- musculoskeletal system
- cardiovascular system
- respiratory system
- digestive system
2
Q
____% of patients with renal insufficiency show oral signs & symptoms in soft hard tissues
A
90%
3
Q
_____ & _____ of body fluid compartments are essential for homeostasis
A
- Constant volume
- Stable composition
4
Q
In order to maintain body fluid homeostatis ____ & ____ in must equal ____ & ____ out
A
Water & electrolytes; water & electrolytes out
5
Q
Fluid distribution in the body influences:
A
Electrolyte concentrations
6
Q
Electrolytes concentrations influence:
A
Fluid distribution in the body
7
Q
What causes water gain?
A
- Food & drink
- Metabolism
8
Q
Where can water be lost?
A
- Skin
- Lungs
- Urine
- Feces
9
Q
Sweat & evaporation leading to water loss occur where:
A
Lungs & skin
10
Q
What is insensible water loss?
What does this mean?
A
Sweat & evaporation; can’t be controlled
11
Q
Urine output is typically ____ but varies to create ____
A
1.5L/day; balance
12
Q
What amount insensible water loss do we have per day?
(70kg man)
A
0.9L/ day
13
Q
How much water is lost through feces per day?
(70kg man)
A
0.1 L/day but varies
14
Q
What amount of water gain brought in through food & drink per day?
(70kg man)
A
2.2 L/day
15
Q
How much water gain does metabolism bring in per day?
(70kg man)
A
0.3L/day
16
Q
We want the extracellular fluid & intracellular fluid volumes to be:
A
Constant
17
Q
Imbalances change vascular & total body volumes:
A
Na+
18
Q
The primary determinant of extracellular fluid osmolarity & tonicity:
A
Na+
19
Q
Any changes in sodium will change water distribution in the body because:
A
Where the salt goes water follows
20
Q
Imbalance alters cardiac & neural functions:
A
K+
21
Q
Potassium plays a role in our:
A
Excitable tissues
22
Q
Imbalances alters skeletal muscle, cardiac, neural function & bone structure:
A
Ca++
23
Q
Necessary for synaptic transmission, skeletal/cardiac/smooth muscle contraction & one of the primary components making up the bone:
A
Ca++
24
Q
H+ comes mainly from:
A
Metabolism
25
Imbalances of this ion alters multiple systems
H+
26
Imbalances in pH impacts multiple systems because pH impacts:
Protein function
27
Extracellular fluid makes up _____% of the body weight in kilograms
Intracellular fluid makes up ____% of the body weight in kilograms
ECF = 20%
ICF = 40%
28
Extracellular fluid breaks down into:
Plasma & interstitial fluid
29
ECF found within the blood vessels:
Plasma
30
ECF found outside of blood vessels & outside of cells:
Interstitial fluid
31
When we consume substances, those substances get added to the:
Plasma
32
Once substances are consumed & added to the plasma, the capillaries immediately exchange that substance with the _____ through the capillary wall
Interstitial fluid
33
What fluid makes up 4-5% of our body weight in kilograms?
Plasma
34
Our is comprised of:
____L of intracellular fluid
____ L of extracellular fluid
The ECF breaks down into
____L of interstitial fluid
____L of plasma
28- ICF
14- ECF
11 IF
3 Plasma
35
Plasma and interstitial fluid are extremely similar in composition, the only thing that cannot move back & forth between these compartments are:
Proteins
36
The _____ is impermeable to proteins:
Capillary membrane
37
In a 70kg adult, total body water volume is _____L, making up____% of body weight (kg)
42L
60%
38
What is the barrier between the ECF & ICF?
Plasma membrane
39
What ions are in a higher level in the extracellular fluid?
1. Na+
2. Ca++
3. Cl-
4. HCO3-
5. Glucose
40
What ions are in a higher level in the intracellular fluid?
1. K+
2. Mg ++
3. H+
4. Amino acids
41
Describe the amount of protein in the inside of the cell relative to the amount of protein on the outside of the cell:
A lot more protein inside the cell than outside, but almost all protein on the outside is found in the plasma
42
Hypervolemia:
Hypovolemia:
Normo/eu-volemia
High blood volume
Low blood volume
Normal blood volume
43
Hypernatremia:
Hypo natiremia:
Normo/eu-natremia:
High blood sodium
Low blood sodium
Normal blood sodium
44
Hyperkalemia:
Hypokalemia:
Normo/eukalemia:
High blood potassium
Low blood potassium
Normal blood potassium
45
Hyercalcemia:
Hypocalcemia:
Normo/eucalcemia:
High blood calcium
Low blood calcium
Normal blood calcium
46
Because the capillary wall is a very leaky barrier ____ & ____ mix rapidly excepting for _____
Plasma & interstitial fluid; proteins
47
What causes the mixing of plasma & interstitial fluids?
Hydrostatic & colloid osmotic pressure vai capillary pores & bulk flow
48
Hydrostatic & colloid osmotic pressure via capillary pores is the main force governing:
Bulk flow
49
Movement of substances between plasma & interstitial fluid occurs via:
Bulk flow
50
Fluid distribution between ICF & ECF is determined by ________ of _____ acting across cell membrane
Osmotic effect of small solutes
51
Water will move down a free water gradient & this free water gradient is determined by the concentration of:
Impermeable substances
52
What adds up to equal around 90% of total ECF osmolarity?
Na+ & Cl- (& other anions)
53
Anytime we have a change in extracellular fluid osmolarity what affect will this have on tonicity? Why?
We will also have a change in tonicity because these substances are impermeable (Na+ & Cl-)
54
What adds up to equal around 90% of total ICF osmolarity?
K+ (& other ions)
55
The cell membrane may also be referred to as:
Plasma membrane
56
Describe the cell membranes permeability to water:
High dependent on where you are in the body
57
Describe the cell membranes permeability to Na+, Cl- & other electrolytes:
Relatively impermeable to small solutes such as these
58
Why would changes in the concentration of Na+, Cl- & other electrolytes change the tonicity & water distribution in the body?
Because the cell membrane is relatively impermeable to these small solutes
59
Cell volume is at the mercy of:
ECF tonicity
60
If a cell is placed in a hypertonic bathing solution, what will happen to the volume of the cell:
Cell will shrink
61
Concentration of impermeable substances in the bathing solution is greater than the concentration of impermeable substances inside the cell: How would you describe this bathing solution?
Hypertonic solution
62
If a cell is placed in an isotonic bathing solution, what will happen to the volume of the cell:
No change in cell volume
63
Concentration of impermeable substances in the bathing solution is equal to the concentration of impermeable substances inside the cell: How would you describe this bathing solution?
Isostonic solution
64
Is there movement of water between the bathing solution and the cell in an isotonic solution?
Yes there is movement, but no net movement
65
Concentration of impermeable substances in the bathing solution is less than the concentration of impermeable substances inside the cell: How would you describe this bathing solution?
Hypotonic solution
66
If a cell is placed in a hypotonic bathing solution, what will happen to the volume of the cell?
Cell swells
67
Composition & volume of ECF change determines composition & volume of:
Fluid replacement
68
_____ & _____ are constantly being challenged in the body:
ECF osmolarity & volume
69
Why can the skin being burned cause such extensive waterloss?
Because the skin a major water-proofing organ
70
If a _____ solution is added into a normal individuals, the ECF volume is increased, the ECF osmolarity is unchanged & the ICF osmolarity & volume are both unchanged
Isotonic
71
If a _____ solution is added into a normal individual, the osmolarity & volume will expand, creating an osmotic gradient for water to move out of the cells into the ECF, further expanding it & reducing the volume in the ICF, raising the ICF osmolarity
Hypertonic
72
If a _____ solution is added into a normal individual, this will lower the ECF osmolarity & raise the ECF volume, creating a gradient causing the water to move into the ICF via osmosis increasing the volumes of both ECF & ICF & decreasing the osmolarities of both ECF & ICF
Hypotonic solution
73
The kidneys regulate body fluid volume & composition by controlling:
ECF volume & ECF composition
74
Too much water in tissues
Edema
75
What are the two types of edema?
Which is more common?
Extracellular & intracellular; extracellular
76
Describe what extracellular edema is:
Too much water in extracellular space
77
Describe what intracellular edema is:
Too much water in intracellular space
78
What are the three causes of intracellular edema?
1. Hyponatremia
2. Decreased metabolism: Na+/K+ pump failure
3. Inflammation
79
How does hyponatremia lead to intracellular edema?
If you don't have enough Na+ you will lower the osmolarity of the ECF (because Na+ is higher in ECF) & this will cause water to rush into the cell = intracellular edema
80
How does decreased metabolism (blood flow): Na+/K+ pump failure lead to intracellular edema?
The Na+/K+atpase typically pumps two K+ into the cell for every three Na+ out of the cell, if this isn't functioning properly Na+ can build up in cell and water will follow
81
How does inflammation (with a cause of things such as infection & burns) lead to hyponatremia?
Inflammation leads to increased membrane permeability & leakage, this would lead to alot of extra ions in the cell and water will follow
82
The most important cation in the body:
Sodium
83
Na+ salts make up >90% of _____ solute in the _____
osmotically active solute; ECF
84
Na+ is highly ______ therefore ECF ______ is highly ____
Regulated; Regulated
85
Too little ECF volume leads to: (3)
1. Volume contraction
2. Hypotension
3. Organ hypoperfusion
86
Too much ECF volume leads to: (4)
1. Edema
2. Ascites
3. Pleural effusion
4. Hypertension
87
What ion do we look at to determine water balance?
Na+
88
When the concentration of Na+ is below normal in the ECF:
Hyponatremia
89
In hyponatremic individuals, what is their sodium level:
Less than 142 mOsm/L
90
Na+ input < Na+ output
or
H2O input > H2O output
These would both lead to:
Hyponatremia
91
Most common electrolier disorder in clinical practice:
Hyponatremia
92
Hyponatremia may account for ______ of hospitalized patients
20-25%
93
What are the three types of hyponatremia?
1. Hyponatremia-dehydration
2. Hyponatremia-overhydration
3. Hyponatremia-low solute intake
94
A type of hyponatremia characterized by increased NaCl loss:
Hyponatremia-dehydration
95
Hyponatremia dehydration may be caused by (5):
1. Vomiting
2. Diarrhea
3. Renal disease
4. Diuretics
5. Addison's disease
96
A type of hyponatremia characterized by excessive H2O retention:
Hyponatremia-overhydration
97
Hyponatremia-overhydration may be caused by (2):
1. Inappropriate ADH secretion
2. H2O toxicity
98
How does Addison's disease lead to hyponatremia-dehydration?
Aldosterone stimulates Na+ reabsorption in the kidneys, so if we don't have enough aldosterone, we won't have enough sodium brought back into the body
99
Drinking too much water too quickly:
H2O toxicity
100
How can inappropriate ADH secretion lead to hyponatremia-overhydration?
ADH causes water retention, so too much ADH will cause too much water to be retained which will dilute the ECF too much leading to hyponatremia
101
A type of hyponatremia characterized by decreased NaCl intake:
Hyponatremia-low solute intake
102
What may be a cause of hyponatremia-low solute intake?
Extreme diets (rare)
103
Characterized by a gradual decrease (can take weeks to months) in Na+ concentration in the ECF:
Chronic hyponatremia
104
Chronic hyponatremia stimulates transport of ___, ____ and ____ (in/out) of the cells
This causes water diffusion (in/out) of the cells
Na+, K+ and organic solutes; out
out
105
With chronic hypotanremia, the brain swelling is attenuated by:
transport of solutes from the cell
106
Why must chronic hyponatremia be fixed slowly?
To avoid osmotic demyelination
107
A rapid decrease in the Na+ concentration of the ECF:
Acute hyponatremia
108
Acute hyponatremia can be caused by: (2)
1. Loss of Na+
2. Excess H2O
109
In acute hyponatremia water rushes (into/out) of the cells
into
110
In acute hyponatremia, what does the water rushing into the cells cause?
Swelling of the brain tissue
111
Not properly hydrating for a marathon leading can cause what type of hyponatremia?
Acute hyponatremia
112
Increased interstitial fluid volume causes:
Extracellular edema
113
What are the common causes of extracellular edema?
1. Increased capillary filtration
2. Lymphedema
1. Increased capillary permeability
2. Increased capillary hydrostatic pressure
3. Decreased capillary colloid osmotic pressure
114
Failure of lymphatics to return interstitial fluid to circulation:
Lymphedema
115
What is the most common reason for extracellular edema?
Increased capillary filtration
116
What is an example of a condition that may cause increased capillary filtration leading to extracellular edema?
Congestive heart failure
117
Determine whether each of the following pressures is a filtration or absorption force:
- Capillary pressure (Pc)
- Interstitial fluid pressure (Pisf)
- Plasma Colloid Osmotic pressure (Pi-c)
- Interstitial colloid osmotic pressure (Pi-isf)
(Pc)- filtration
(Pisf)- absorptive
(Pi-c)- absorptive
(Pi-isf)- filtration
118
K(f) is a constant for:
Membrane permeability
119
K(f) is a function of:
The surface ares & membrane permeability
120
Equation for filtration rate:
Filtration rate=
K(f)((Pc+Pi-if)-(Pif+Pi-c))
121
What does it mean if the filtration rate is a positive value?
What does it mean if the filtration rate is a negative value?
Positive value: overall net filtration out of capillaries
Negative value: overall net absorption into capillaries
122
How does increased capillary permeability lead to extracellular edema?
This allows more water and proteins to escape and if the proteins escape to the interstitial fluid that causes colloid osmotic pressure of the interstitial fluid, this will draw more water out and lead to extracellular edema
123
What are some examples of conditions that make the capillaries more permeable? (3)
1. Inflammation (infection, immune reactions)
2. Burns
3. Ischemia
124
What are some conditions that can cause increased capillary hydrostatic pressure which ultimately leads to extracellular edema? (2)
1. Heart failure
2. Renal disease
125
_____ leads to extracellular edema all over the body, while _____ leads to extracellular edema in pulmonary circulation
Generalized heart failure; left heart failure
126
What can cause decreased capillary colloid osmotic pressure which can ultimately lead to extracellular edema: (2)
1. Renal loss (nephrotic syndrome)
2. Liver disease
127
How can liver disease liver disease cause decreased capillary colloid osmotic pressure?
Bc the liver produces the plasma proteins so if the liver is not functioning we aren't getting enough plasma proteins
128
Describe what happens when someone has nephrotic syndrome:
You start losing proteins in the urine and this decreases colloid osmotic pressure leading to edema
129
The buildup of fluid in other potential spaces like the pleural, pericardial, peritoneal and synovial cavities:
Effusions
130
What are the potential spaces that an effusion may occur in? (4)
1. pleural cavity
2. pericardial cavity
3. peritoneal cavity
4. synovial cavity
131
Effusions can happen, because lining membranes are highly:
Permeable
132
Important for clearing fluids and proteins
Lymphatic drainage
133
A buildup of fluid in the peritoneal space:
Ascites
134
What are the changes in the following variable after giving 2.0L of water I.V.?
- ECF volume
- ECF osmolarity
- ICF volume
- ICF osmolarity
- increase
- decrease
- increase
- decrease
135
The kidneys regulate body fluid volume & composition by controlling: (2)
1. ECF volume
2. ECF composition
