Fluid Compartments & Fluid Shifts- Exam 2 Flashcards
1
Q
What needs to be stable for cells to perform at an optimum level?
A
Stable external environment
2
Q
What must be constant to maintain a stable external environment?
A
Overall volume and composition of the body fluids
3
Q
What organ plays a major role in maintaining the body fluids in terms of volume and composition?
A
Kidneys
4
Q
What is the daily fluid intake?
A
2300 mls/day
5
Q
How much of the daily intake is by oxidation of carbohydrates?
A
200 mls/day
6
Q
How much of the daily intake is by ingested fluids?
A
2100 mls/day
7
Q
What is the fluid loss/output per day?
A
2300 mls/day
8
Q
How much of fluid loss is insensible loss via respiratory tract and skin (not sweat)?
A
700 mls/day
9
Q
How much of fluid loss is sweat?
A
100 mls/day
10
Q
How much of fluid loss is feces?
A
100 mls/day
11
Q
How much of fluid loss is urine?
A
1400 mls/day
12
Q
How much of the body is normally water?
A
Male: 60% body weight
Female: 50% body weight (more fat)
13
Q
How much of body weight is ECF?
A
20%
14
Q
How much of body water is ECF?
A
1/3 total volume
15
Q
How much of ECF is interstitial fluid?
A
75% of ECFV
16
Q
How much of ECF is plasma?
A
25% of ECFV; composition similar to ISF
17
Q
How much of water is transcellular fluid?
A
1 to 2 liters
18
Q
What are some examples of transcellular fluid?
A
Synovial Peritoneal Pericardial Intraocular Cerebrospinal
19
Q
How much of body weight is intracellular fluid?
A
40% of body weight
20
Q
How much of body water is intracellular fluid?
A
2/3 total volume
21
Q
Concentration of the non-electrolytes of the plasma
A
Phospholipids- 280 mg/dl Cholesterol- 150 mg/dl Neutral Fat- 125 mg/dl Glucose- 100 mg/dl Urea- 15 mg/dl Lactic acid- 10mg/dl Uric acid- 3 mg/dl Creatinine- 1.5 mg/dl Bilirubin- 0.5 mg/dl Bile salts- Trace
22
Q
What 4 forces influence distribution between plasma and interstitial compartments?
A
Capillary hydrostatic pressure
Interstitial hydrostatic pressure
Capillary colloid oncotic pressure
Interstitial colloid oncotic pressure
23
Q
What two ions control distribution between intracellular an extracellular compartments across membranes?
A
sodium and chloride
24
Q
What kind of permeability do cell membranes have for water?
A
High permeability
25
What type of permeability do cell membranes have for solute?
Low permeability
26
What moves quickly into or out of the cell to keep ICF isotonic with ECF?
water
27
Osmole
means of measuring total concentration of particles in solution
28
1 osmole is how many moles of particles?
1 mole of particles (6.02 x 10^23 particles)
29
1 mole glucose in 1 liter is how many osm/L?
1 osmole/L of glucose
30
1 mole salt in 1 liter is how many osm/L of sodium and chloride?
2 osm/L of sodium and chloride
31
1 mole sodium sulfate (Na2SO4) in 1 liter is how many osm/L
3 osm/L
32
1mOsm is how many osmoles?
1/1000 osmoles
33
Osmolality
osmoles/kg water
34
Osmolarity
osmoles/L water
35
Plasma Osmolarity
301.8 mOsm/L (plasma protein)
36
Interstitial Osmolarity
300.8 mOsm/L
37
Intracellular Osmolarity
301.2 mOsm/L
38
Each mOsm of solute that cannot cross membrane generates what pressure?
Osmotic pressure of 19.3 mmHg
39
_________ changes in the concentration of impermeable solut will create _______ shifts of water creating large changes in compartment volumes.
Small; large
40
Isotonic solution
```
Same osmolarity (i.e. same concentration of impermeant solutes)
Will not upset osmotic balance between intra and extracellular fluid when administered
0.9% sodium chloride (0.9 grams of NaCl/100mls solution = 9 grams/L)
```
41
Isosmotic
Solutions with same osmolarity as intracellular osmolarity even if some solute is permeable
42
Hypo-osmotic
solutions with lower osmolarity than intracellular fluid even if some solute is permeable
43
Hyperosmotic
solutions with higher osmolarity than intracellular fluid even if some solute is permeable
44
Causes of osmotic imbalance
water ingestion
dehydration
fluid loss from GI tract
abnormal fluid loss by sweating or kidneys
45
What will happen if the osmoliarty of a solution is the same as ECF
No change in ECF osmolarity
| Expand volume of ECF by volume of solution
46
If you add a liter of normal saline....
the liter starts in the plasma of the CBV within 15 minutes 75% will move to the interstitial fluid and 25% will remain i the CBV
47
What is the most common nutrient solution?
Glucose
48
What are nutrient solutions adjusted to?
To or nearly isotonic
49
What happens if a nutrient solution is not adjusted to be isotonic?
Given slowly so it does not upset balance
50
As nutrient solution is metabolized, patient is left with what?
Surplus of water; usually removed by the kidney
51
What is a good measure of plasma osmolarity?
Plasma sodium concentration
52
Sodium and chloride account for what percent of solute in the ECF?
90%
53
What is the normal plasma sodium concentration?
142 mEq/L
54
Hypernatremia
higher than normal osmolarity
55
Hyponatremia
lower than normal osmolarity
56
What is the effect of hyponatremia? (Loss of sodium)
Decrease in plasma [Na+]
Decreased ECFV
Increased ICFV
57
What is hyponatremia?
Loss of sodium from ECF
| Addition of excess water to ECF
58
What causes hyponatremia? (Loss of sodium)
Diarrhea & vomiting
Diuretic overuse (inhibits ability to conserve sodium)
Renal disease that "wastes" sodium
Addison's disease results form decrease secretion of aldosterone
59
What is the effect of hyponatremia? (excess water)
Decrease in plasma [Na+]
Increased ECFV
Increased ICFV
60
What causes hyponatremia? (Excess water)
Excess water retention
| Excessive secretion of ADH
61
What is a major consequence of hyponatremia?
Cell swelling; cerebral edema is a major problem
62
What are some symptoms of hyponatremia?
headache; nausea; lethary; disorientation
63
What concentrations of sodium cause significant problems?
120-115 mEq/L range
64
What does low concentration of sodium cause?
```
Significant brain swlling
Seizures
Coma
Permanent brain damange (if volume increases by 10%)
death
```
65
Brain volume must increase by how much to get permanent brain damage?
10%
66
How does brain attempt to compensate for hyponatremia?
Moving sodium, chloride, potassium, organic solutes from cells out to ECF
67
What is the max rate the brain can compensate for hyponatremia?
10 to 12 mmol/L over 24 hours
68
What is the most common electrolyte disorder?
Hyponatremia
69
What percent of hospitalized patients have hyponatremia?
15-25%
70
What is hypernatremia?
Water loss from the ECF
| Addition of excess sodium into the ECF
71
What is the effect of hypernatremia? (Water loss)
Incraesed plasma [Na+]
Decreased ECFV
Decreased ICFV
72
What causes hypernatremia? (water loss)
inability to secrete ADH (needed for urine concentration)- produce large amounts of dilute urine (diabetes insipidus)
Excessive sweating so output greater than intake
73
What condition produces a large amount of dilute urine?
Diabetes insipidus
74
What are the effects of hypernatremia? (excess sodium)
Increased plasma [Na+]
Increased ECFV
Decreased ICFV
75
What causes hypernatremia? (excess sodium)
excessive secretion of aldosterone
| Resorbs water and sodium
76
What are the consequences of hypernatremia?
Tissue cells shrink
77
What sodium concentration will result in hypernatremia?
158-160 mEq/L
78
Why is hypernatremia not very common?
Results in excessive thirst
79
What disease causes impaired thirst reflex?
Hypothalamic disease
80
What causes intracellular edema?
Hyponatremia
Depression of metabolic systems within cells
Lack of adequate nutrition delivery to cells
Inflammation
81
What causes depression of metabolic systemis within cells?
Sodium-potassium pump- shift of sodium into cell
82
What does inflammation result in?
Increased cellular permeability- shift sodium into cell
83
What causes extracellular edema? (slides)
Abnormal leakage of fluid from plasma to interstitial space across the capillary
Failure of lymphatics to return fluid to vascular system
84
What are the 4 main causes of extracellular edema? (book)
1. Increased capillary edema
2. Decreased plasma proteins
3. Increased capillary permebaility
4 .Blockage of lymph return
85
What can cause increased capillary pressure?
Excessive kidney retention of salt and water
High venous pressure and venous constriction
Decreased arteriolar resistance
86
What can cause excessive kidney retention of salt and water?
Acute or chronic renal failure
| Mineralcorticoid excess
87
What can cause high venous pressure?
Heart failure
Venous obstruction
Failure of venous pumps (paralysis of muscles, immobilization of parts of body, failure of venous valves)
88
What can cause decreased arteriolar resistance?
Excessive body heart
Insufficiency of sympathetic nervous system
Vasodilator drugs
89
What can cause decreased plasma proteins?
loss of proteins in urine (nephrotic syndrome)
| loss of protein from denuded skin areas (burns, wounds)
90
What causes failure to produce proteins?
```
liver disease (cirrhosis)
serious protein or caloric malnutrition
```
91
What causes increased capillary permeability
```
immune rxns that cause release of histamine and other immune products
toxins
bacterial infections
vitamin deficiency, especially vitamin C
prolonged ischemica
burns
```
92
What causes blockage of lymph?
Cancer
infections (filaria nematodes)
surgery
congenital absence or abnormality of lymphatic vessels
