Fluids, acids, & electrolytes Flashcards
(153 cards)
1
Q
a solvent that dissolves and transports body salts, nutrients, and wastes.
A
water
2
Q
What does water regulate?
A
Water regulates body temperature, lubricates joints and membranes, and is the medium for food digestion
3
Q
Total body water is expressed as a percentage (%) of body weight; I litre of water = ??
A
1 litre of water= 1kg (2.2lbs)
4
Q
What is the percentage of water found in each of the following:
Adults
Infants
Older adults
A
Adults: 60%
Infants: 70-80%
Older adults: 45-55%
5
Q
The intracellular fluid accounts for what percentage of body mass?
A
42%
6
Q
What are the two types of extracellular fluid?
A
interstitial
intravascular
7
Q
space between cells and outside blood vessels (15% TBW)
A
interstitial
8
Q
plasma - the fluid component of the blood vessels (5% TBW)
A
Intravascular
9
Q
the extracellular fluid makes up what percentage of body mass?
A
20%
10
Q
What is transcellular fluid?
A
fluid found in the cerebrospinal, gastric, pleural, synovial, peritoneal fluids
11
Q
occurs when too much fluid moves from the intravascular space (blood vessels) into the interstitial or “third” space-the nonfunctional area between cells
A
third spacing
can cause hypotension, edema and reduced cardiac output
12
Q
What is the total daily intake (mL) and totally daily output for water?
A
intake: 2400-3200
output: 2400-3200
13
Q
What are electrolytes?
A
Substances whose molecules dissociate or split when placed in solution
14
Q
What are electrolytes composed of?
A
ions
15
Q
What is an ion?
A
electrically charged particles
16
Q
What is a cation?
A
positively charged ions
17
Q
What are some examples of cations?
A
Sodium (Na+)
Potassium (K+)
Calcium (Ca2+)
Magnesium (Mg2+)
18
Q
What are anions?
A
negavtiely charged ions
19
Q
What are some examples of anions?
A
Bicarbonate (HCO-3)
Chloride (Cl-)
Phosphate (PO3-
20
Q
Most proteins bare what type of charge? What does this classify them as?
A
Negative; anions
21
Q
What is the international standard for measuring electrolytes?
A
Milliemoles (mmo/L)
22
Q
substance that is capable of dissolving a solute(liquid or gas
A
solvent
23
Q
homogenous mixture of solutes dissolved in a solvent
Solute: substance that is dissolved in a solvent
A
solution
24
Q
a substance that is dissolved in a solvent
A
solute
25
What is the most prevalent cation in intracellular fluid?
potassium
26
What is the most prevalent anion in intracellular fluid?
phosphate
27
What is the most prevalent anion in extracellular fluid?
chloride
28
Plasma has a substantial amount of this.
protein
29
all fluid that resides inside the cell is known as?
intracellular fluid
30
all fluid that resides outside the cell is known as?
extracellular fluid
31
In all fluids, which has the greatest amount of protein?
intracellular fluid of ICF
32
What is diffusion?
the movement of molecules from an area of high concentration to an area of low concentration
33
What type of permeability must the membrane have in order for diffusion to occur?
must be permeable
34
What type of energy is required for diffusion?
no energy
35
What is facilitated diffusion?
the movement of molecules from an area of high concentration to an area of low concentration BUT they need carrier molecule to facilitate the rate of diffusion
36
What is active transport?
a process requiring energy in which molecules move against the concentration gradient
37
during active transport, _________ moves out of the cell and _______ moves in the cell to maintain its concentration difference
sodium; potassium
38
what is the energy source for the sodium potassium pump and where is it produced?
Adenosine triphosphate (ATP)
mitochondria
39
What is osmosis?
Movement of water between two compartments separated by a membrane permeable to water but not to solutes
40
In osmosis, water moves from an area of _____ solute to _____ solute
low; high
41
Does osmosis require energy? How does this process stop?
No.
| When the concentration gradient is equal OR hydrostatic pressure is high enough to oppose water movement
42
measures milliosmoles of solute per volume solution. (ie. mOsm/Liter of water) VOLUME
Osmolarity
43
this measurement of solute per volume is used to describe fluids outside the body (IV soln., meds)
osmolarity
44
measures osmotic force in terms of unit of weight of solution (ie. mmol/kg of water) WEIGHT
Osmolality
45
this measurement of force is used to describe fluids inside the body
} Body fluids concentration = individual’s hydration status
} aka - tonicity
osmolality
46
What is osmolality typically test for?
the concentration of proteins, glucose & AMP; lipids in plasma or urine
47
What does osmolality indicate?
indicates the water balance of the body
48
What is the normal plasma osmolality between?
♣ 285 and 295 mmol/kg
49
What are the major determinants of plasma osmolality?
♣ Glucose, sodium, and urea calculate the effective plasma osmolality based on the concentrations of those compounds
50
fluids with the same osmolality as the cell interior
isotonic fluid (same inside and outside cell)
51
fluids with less concentration of solutes (hypo-osmolar) than the cell interior
Hypotonic Fluid (cell expands)
52
fluids with higher concentration of solutes (hyper-osmolar) than the cell interior
hypertonic fluid (cell shrinks)
53
The ECF and the ICF are isotonic or hypotonic to one another? What does this create?
- isotonic
| - zero net movement occurs because it is equal
54
What happens if a cell is surrounded by hypotonic fluid?
♣ Water moves into the cell, causing it to swell with potential to burst
55
What happens if a cell is surrounded by hypertonic fluid?
♣ Water moves out of the cell to dilute the ECF; the cell shrinks and may eventually die
56
Movement of water, nutrients and waste between intravascular and interstitial spaces occurs due to changes in these pressure systems.
```
hydrostatic
osmotic (oncotic) pressure
```
57
What is the major force of hydrostatic pressure?
the pressure of water pushing out of the intravascular system at the capillary level
58
What is the major force of osmotic (oncotic) pressure?
proteins or colloids
59
What is the major colloid in the vascular system that contributes to the total osmotic pressure?
proteins
60
♣ What are protein molecules attracted to and what do they do with it during oncotic pressure?
Water; pull fluid from tissue space to the intravascular space (blood vessels)
61
♣ What causes the movement of fluid to move out of the capillaries to interstitial space?
Capillary hydrostatic pressure (BP)
62
What causes the movement of fluids from the interstitial space into the capillaries?
interstitial hydrostatic pressure
63
What occurs at the arterial end of the capillary?
Hydrostatic (capillary) pressure exceeds osmotic (plasma) pressure and fluid is moved into the interstitium
64
What occurs at the venous end of the capillary?
fluid is drawn back into the capillary by the osmotic pressure created by plasma proteins
65
What is it called when any fluid moves out of the capillaries into interstitial space?
filtration
66
What is it called when any fluid moves into capillaries from the interstitial space?
reabsorption
67
What fluid shifts can cause edema?
- venous hydrostatic pressure rises
- plasma oncotic pressure decreases
- interstitial oncotic pressure rises
68
What occurs when there is an increase of venous hydrostatic pressure?
Increase in the pressure at the venous end of the capillary inhibits fluid movement back into the capillary
Causes: congestive heart failure, liver failure, obstruction of the venous vein return to the heart
69
What occurs when there is a decrease in plasma omostic pressure?
Fluid remains in the interstitium if the plasma oncotic pressure is too low to draw fluid back into the capillaries
♣ Causes: renal disorders, deficient protein synthesis or protein intake
70
What happens when there is increased ECF Osmolality?
water shifts out of cells until the ECF and ICF have similar osmolality; causes cells to shrink
71
What happens when there is decreased ECF Osmolality?
water shifts into cells until the ECF and ICF have similar osmolality; causing cells to swell
72
BODY FLUID EXCESS=
| _______ plasma OSMOLALITY
decreased
73
BODY FLUID DEFICIT=________ PLASMA OSMOLALITY
increased
74
What is fluid spacing?
a term used to describe the distribution of body water
75
What is first spacing?
♣ First spacing; describes the normal distribution of fluid in the ICF and ECF compartments
76
What is second spacing?
♣ Second spacing: an abnormal accumulation of interstitial fluid (edema)
77
What is third spacing?
♣ Third spacing: occurs when fluid accumulates in a portion of the body from which it is not easily exchange with the rest of the ECF, rendering the fluid trapped and unavailable for functional use
78
What are some examples of third spacing?
♣ Ascites, sequestrastion of fluid in the abdominal cavity with peritonitis, and edema associated with burns
79
A fluid deficit or increase in plasma osmolality is sensed by these receptors.
hypothalamic osmoreceptors
80
What do hypothalamic osmoreceptors do?
stimulate thirst and ADH release
81
Where does water reabsorption occur in the kidneys?
♣ Renal distal and collecting tubules
82
What two actions increase free water in the body and decrease plasma osmolality?
ADH and thirst
83
This hormone causes the distal tubule’s in the collecting ducks in the kidneys to regulate water retention by becoming more _________ to water
♣ ADH; permeable
84
Where does water go once absorbed from the tubular filtrate in the kidneys?
the bladder
85
what are some factors that stimulate ADH release?
Plasma osmolality, stress, nausea, nicotine, morphine
86
What is SIADH? Syndrome of inappropriate ADH
Abnormal ADH production in CNS disorders (brain tumors, brain injury), malignancies (small cell lung CA)
87
This disorder is a result from abnormal water retention, decreased plasma osmolality and increased urine osmolality with decreased urine output
SIADH
88
This disease has an abnormal reduction in the release or action of ADH where the renal tubules and collecting ducts do not reabsorb water, resulting in
copious amounts of dilute urine
Diabetes Insipidus
89
These hormones primarily have an anti-inflammatory effect and increase serum glucose levels
Glucocorticoids
90
What is an example of Glucocorticoids?
cortisol
91
These hormones enhances sodium retention and potassium excretion
Mineralocorticoids:
92
Give an example of Mineralocorticoids.
aldosterone
93
What occurs when sodium is re-absorbed in the cells?
Water follows because of osmotic change
94
In large doses, this hormone acts like a mineralocorticoid; when large doses are released in response to stress, they exert Na+ and water retention action.
Cortisol:
95
What is/are the primary organ/s for regulating fluid and electrolyte balance?
kidneys
96
What is serum?
blood plasma not containing fibrinogens
97
What is the result of the release of hormone Atrial Natriuretic factor (ANF) by the atria in response to increased atrial pressure?
decreased blood volume due to vasodilation and increased urinary exertion of Na+
98
What system accounts for mot of the fluid intake?
GI tract
99
What is the invisible evaporation of fluid from the lungs and skin (not sweat from sweat glands – this is sensible perspiration d/t fever, high environmental temperatures)
known as?
insensible water loss
100
What is the normal insensible water loss?
900mL daily
101
Mild fluid and electrolyte imbalances can be corrected with oral rehydration solutions containing these.
water, lytes, glucose
102
What are the three classifications of solutions?
isotonic
hypotonic
hypertonic
103
What Iv solution has the same osmolality or concentration of solutes as ICF or ECF
280-300 mOsm/L (same as serum)
isotonic
104
What IV has a lower concentration of solutes =
more dilute than ICF or ECF
< 280 mOsm/L
Hypotonic Solution:
105
What IV has a higher concentration of solutes = more concentrated than ICF or ECF
> 300 mOsm/L
Hypertonic Solution
106
Isotonic IV solutions expand the ICF or the ECF?
ECF (intravascular, interstitial)
107
What is the indication for using isotonic solutions?
fluid replacement for ECF volume deficit
108
What are the solutions for using an isotonic solution when there is ECF volume deficit?
- lactated ringers
- normal saline (NS-0.9% NaCl)
- dextrose 5% in water (isotonic in the bag, hypotonic in the bloodstream)
109
Where do IV isotonic solutions stay when infused?
they stay where they are infused, in the intravascular space
110
What are the risks associated with isotonic IV solutions?
fluid overload, esp. with older adults, CHF
111
What element manages the osmotic balance of the ECF?
Na+ sodium
112
What element manages the osmotic balance of the ICF?
potassium K+
113
What is hypernatremia?
♣ An electrolyte problem that is defined as a rise in serum sodium concentration to a value exceeding 145 mmol/L.
114
♣ What is the primary protection against the development of hyperosmolality?
Thirst; as plasma osmolality increase, the thirst center in the hypothalamus is sitmluated, and the individual seeks fluid
115
What are other causes of hypernatremia?
- sodium gain (IV administration of hypertonic saline or sodium bicarbonate), deficit in ADH, mannitol, decrease in kidney response to ADH
116
This electrolyte problem is defined as a hyperosmolar or condition caused by a decrease in total water relative to electrolyte content
hypernatremia
117
What is hyponatremia?
♣ An electrolyte problem that results from loss of sodium containing fluids or from water excess
118
What can come from hyponatremia?
extracellular hyposmolality
119
What causes hyponatrmeia?
♣ it can be caused by water excess and inappropriate use of sodium-free or hypotonic IV fluids.
120
What percentage does Potassium is in ICF?
98%
121
♣ The sodium-potassium pump maintaints 140 mmol/L of potassium in the body by pumping ________ into the cell and _________ out of the cell.
o Potassium; sodium
122
♣ What type of osmolality does potassium regulate?
o Intracellular osmolality and promotes cellular growth
123
♣ How do the kidneys regulate the ECF concentrations of sodium?
The kidneys excrete or retain water under the influence of ADH (antidiuretic hormone)
124
What is hyperkalemia?
♣ High serum potassium
125
What causes hyperkalemia?
A massive intake of potassium, impaired renal excretion, shift of potassium from the ICF to the ECF, or a combination of these factors
o
126
What is the most common cause of hyperkalemia?
kidney failure
127
This condition is associated with the shift of potassium ions from the ICF to the ECF as hydrogen ions move into the cell, producing large amounts of acids.
metabolic acidosis
128
What are some clinical complications of metabolic acidosis?
causes membrane depolarization, altering cell excitability. Skeletal muscles become paralyzed or weak
o cramping, leg pain
o ventricular fibrillation or cardiac standstill may occur
o dysrhythmia
129
What are the treatments for someone with metabolic acidosis?
- Treated by illuminating oral and parenteral potassium intake
- The use of diuretics and increased fluid intake
- Force potassium from the ECF to the ICF vi IV insulin
- Administer calcium gluconate intravenously
130
how many moles of sodium are in the body?
135-155 mmol/L
131
how many moles of potassium are in the body?
3.5-5.0 mmol/L
132
What is the primary intracellular cation?
potassium
133
What percentage does potassium make up in the ICF?
98% ((ICF 150-160 mEq/L vs. ECF 3.5-5.0 mEq/L))
134
What is potassium maintained by?
sodium-potassium pumps
135
potassium is primarily excreted by what?
the kidneys
136
What are some functions of potassium?
- Regulates ICF osmolality and fluid balance
- Regulates intracellular neutrality in relation to H+ and Na+
- Deposits glycogen and glucose in the liver and muscles
- Maintains the resting potential in the transmission/conduction of nerve impulses
- Maintains normal cardiac rhythm
- Maintains contraction of skeletal and smooth muscle
137
Serum Ca2+ has an inverse relationship with which element or compound?
PO4- phosphate
138
What are some functions of calcium?
- Transmission of nerve impulses
- Muscle contraction including the myocardium
- Blood clotting
- Formation of teeth and bones
139
What are the three types of serum
Free or ionized Ca2+ – biologically active
Bound to protein - albumin
Complexed with phosphate, citrate, carbonate
140
What are the functions of phosphate?
Essential to function of muscle
- RBCs, nervous system
- Acid-base balance
- Energy production (ATP)
141
What is the second most abundant intracellular cation?
magnesium
142
Where is 50-60% of magnesium stored?
the bones
143
How is magnesium regulated?
by the GI absorption and renal exertion
144
This element influences Mg2+ balance, and the manifestations of these imbalances mimic each other
Ca2+
145
What are some functions of magnesium?
- Assists in metabolism of protein and carbohydrates
- Smooth muscle contraction/relaxation
- Important for cardiac function
146
Sodium has an inverse relationship with what element in the kidneys?
potassium K+
147
What is an inverse relationship?
one in which one molecule decreases the other increases
148
♣ Potassium is critical for many cellular and metabolic functions. What are these fucntions?
o The transmission and conduction of nerve impulses, maintenance of normal cardiac rhythms, and skeletal and smooth muscle contractions
149
this solutions push fluids into the cells and interstitial spaces
Hypotonic solutions
150
this solution pull fluids from the cells and interstitial space into the intravascular space.
hypertonic solutions
151
what are some risks of hypertonic solutions?
fluid overload, cellular dehydration
152
normal sodium levels
135-145 mmol/L
153
normal potassium levels
3.5-5.0 mmol/L
