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2 - Keiser A&P 2 > 0-1 Chapter 24 - water, electrolytes, acid-base balance > Flashcards

0-1 Chapter 24 - water, electrolytes, acid-base balance Flashcards

1
Q

Balance

A

cellular function requires a fluid medium with a carefully controlled composition
•balances maintained by the collective action of the urinary, respiratory, digestive, integumentary, endocrine, nervous, cardiovascular, and lymphatic systems

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2
Q

three types of homeostatic balance

A

water balance
electrolyte balance
acid-base balance

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3
Q

water balance

A

•average daily water intake and loss are equal

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4
Q

electrolyte balance

A

the amount of electrolytes absorbed by the small intestine balance with the amount lost from the body, usually in urine

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5
Q

acid-base balance

A

•the body rids itself of acid (hydrogen ion –H+) at a rate that balances metabolic production

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6
Q

Body Water

A
  • newborn baby‟s body weight is about 75% water
  • young men average 55% -60%
  • women average slightly less
  • obese and elderly people as little as 45% by weight
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7
Q

total body water (TBW)

A

of a 70kg (150 lb) young male make is about 40 liters

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8
Q

major fluid compartments of the body

A

–65% intracellular fluid (ICF)

–35% extracellular fluid (ECF)

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9
Q

–35% extracellular fluid (ECF)

A
  • 25% tissue (interstitial) fluid
  • 8% blood plasma and lymphatic fluid
  • 2% transcellular fluid „catch-all‟ category
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10
Q

transcellular fluid „catch-all‟ category

A

–cerebrospinal, synovial, peritoneal, pleural, and pericardial fluids
–vitreous and aqueous humors of the eye
–bile, and fluids of the digestive, urinary, and reproductive tracts

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11
Q

Water Movement Between Fluid Compartments

A

•fluid continually exchanged between compartments
•water moves by osmosis
•because water moves so easily through plasma membranes, osmotic gradientsnever last for very long
•if imbalance arises, osmosis restores balance within seconds so the intracellular and extracellular osmolarity are equal
–if osmolarity of the tissue fluid rises, water moves out of the cell
–if it falls, water moves in

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12
Q

osmosis from one fluid compartment to another is determined by

A

the relative concentrations of solutes in each compartment
–electrolytes–the most abundant solute particles, by far
–sodium salts in ECF
–potassium salts inICF

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13
Q

electrolytes

A

electrolytesplay the principal role in governing the body‟s water distribution and total water content

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14
Q

fluid balance

A

when daily gains and losses are equal (about 2,500 mL/day)

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15
Q

Water gains come from two sources:

A

–preformed water (2,300 mL/day)
•ingested in food (700 mL/day) and drink (1600 mL/day)
–metabolic water (200 mL/day)
•by-product of aerobic metabolism and dehydration synthesis

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16
Q

sensible water loss

A

is observable
–1,500 mL/ day is in urine
–200 mL/day is in feces
–100 mL/day is sweat in resting adult

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17
Q

insensible water loss

A

is unnoticed
–300 mL/day in expired breath
–400 mL/day is cutaneous transpiration
•diffuses through epidermis and evaporates
–does not come from sweat glands
–loss varies greatly with environment and activity

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18
Q

obligatory water loss

A

output that is relatively unavoidable

•expired air, cutaneous transpiration, sweat, fecal moisture, and urine output

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19
Q

thirst

A

mainly governs fluid intake

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20
Q

dehydration

A

–reduces blood volume and blood pressure

–increases blood osmolarity

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21
Q

osmoreceptors in hypothalamus

A

–respond to angiotensin II produced when BP drops and to rise in osmolarity of ECF with drop in blood volume
–osmoreceptors communicate with the hypothalamus and cerebral cortex

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22
Q

hypothalamus produces

A

antidiuretic hormone

•promotes water conservation

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23
Q

cerebral cortex produces

A

conscious sense of thirst

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24
Q

intense sense of thirst

A

with 2-3% increase in plasma osmolarity or 10-15% blood loss

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25
Q

salivation

A

is inhibited with thirst

•sympathetic signals from thirst center to salivary glands

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26
Q

long term inhibition of thirst

A

–absorption of water from small intestine reduces osmolarity of blood
•stops the osmoreceptor response, promotes capillary filtration, and makes the saliva more abundant and watery
•changes require 30 minutes or longer to take effect

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27
Q

short term inhibition of thirst

A

–cooling and moistening of mouth quenches thirst
–distension of stomach and small intestine
–30 to 45 min of satisfaction
•must be followed by water being absorbed into the bloodstream or thirst returns
–short term response designed to prevent overdrinking

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28
Q

Regulation of Water Output

A

only way to control water output significantly, is through variation in urine volume
–kidneys can‟t replace water or electrolytes
–only slow rate of water and electrolyte loss until water and electrolytes can be ingested

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29
Q

mechanisms:

A

–changes in urine volume linked to adjustments in Na+ reabsorption
•as Na+is reabsorbed or excreted, water follows
–concentrate the urine through action of ADH

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30
Q

ADH secretion stimulated by

A

hypothalamic osmoreceptors in response to dehydration

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31
Q

aquaporins synthesized in response to

A

ADH
–membrane proteins in renal collecting ducts whose job is to channel water back into renal medulla, Na+is still excreted
–slows decrease in water volume and increased osmolarity –concentrates urine

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32
Q

ADH release inhibited when

A

blood volume and pressure is too high or blood osmolarity too low
•effective way to compensate for hypertension

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33
Q

Disorders of Water Balance

A

the body is in a state of fluid imbalance if there is an abnormality of total volume, concentration, or distribution of fluid among the compartments

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34
Q

fluid deficiency

A

fluid output exceeds intake over long period of time

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35
Q

volume depletion

A

(hypovolemia)
–occurs when proportionate amounts of water and sodium are lost without replacement
–total body water declines, but osmolarity remains normal
–hemorrhage, severe burns, chronic vomiting, or diarrhea

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36
Q

hypovolemia

A

volume depletion

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37
Q

dehydration

A

dehydration(negative water balance)
–body eliminates significantly more water than sodium
–total body water declines, osmolarity rises
–lack of drinking water, diabetes, ADH hyposecretion (diabetes insipidus), profuse sweating, overuse of diuretics

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38
Q

infants more vulnerable to dehydration than adults due to

A

high metabolic rate that demands high urine excretion, immature kidneys cannot concentrate urine effectively, greater ratio of body surface to mass

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39
Q

most serious effects

A

circulatory shock due to loss of blood volume, neurological dysfunction due to dehydration of brain cells, infant mortality from diarrhea

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40
Q

Fluid Balance in Cold Weather

A

the body conserves heat by constricting blood vessels of the skin forcing blood to deeper circulation
–raises blood pressure which inhibits secretion of ADH
–increases secretion of atrial natriuretic peptide
–urine output is increased and blood volume reduced

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41
Q

cold air is drier and

A

increases respiratory water loss also reducing blood volume

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42
Q

cold weather respiratory and urinary loses cause

A

a state of reduced blood volume (hypovolemia)
–exercise will dilate vessels in skeletal muscles
–insufficient blood for rest of the body can bring on weakness, fatigue, or fainting (hypovolemic shock)

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43
Q

Dehydration from Excessive Sweating

A

1) water loss from sweating
2) sweat produced by capillary filtration
3) blood volume and pressure drop, osmolarity rises
4) blood absorbs tissue fluid to replace loss
5) tissue fluid pulled from ICF
6) all three compartments lose water
7) 300 mL from tissue fluid and 700 mL from ICF

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44
Q

fluid excess

A

less common than fluid deficiency because the kidneys are highly effective in compensating for excessive intake by excreting more urine
–renal failure can lead to fluid retention

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45
Q

two types of fluid excesses

A

volume excess

hypotonic hydration

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46
Q

volume excess

A
  • both Na+ and water retained
  • ECF remains isotonic
  • caused by aldosterone hypersecretion or renal failure
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47
Q

hypotonic hydration

A

(water intoxication) (positive water balance)
•more water than Na+ retained or ingested
•ECF becomes hypotonic
–can cause cellular swelling
–pulmonary and cerebral edema

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48
Q

fluid sequestration

A

a condition in which excess fluid accumulates in a particular location
•total body water may be normal, but volume of circulating blood may drop to a point causing circulatory shock

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49
Q

most common form

A

edema -abnormal accumulation of fluid in the interstitial spaces, causing swelling of the tissues

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50
Q

hemorrhage

A

another cause of fluid sequestration

•blood that pools in the tissues is lost to circulation

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51
Q

pleural effusion

A

several liters of fluid can accumulate in the pleural cavity

•caused by some lung infections

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52
Q

physiological functions of electrolytes

A

–chemically reactive and participate in metabolism
–determine electrical potential (charge difference) across cell membranes
–strongly affect osmolarity of body fluids
–affect body‟s water content and distribution

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53
Q

major cations

A

–Na+, K+, Ca2+, and H+

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54
Q

major anions

A

–Cl-, HCO3-(bicarbonate), and PO43-

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55
Q

great differences between electrolyte concentrations of

A

blood plasma and intracellular fluid (ICF)

–have the same osmolarity (300 mOsm/L)

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56
Q

concentrations in tissue fluid (ECF) differ only

A

slightly from those in the plasma

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57
Q

sodium

A

principal ions responsible for the resting membrane potentials
–inflow of sodium through membrane gates is an essential event in the depolarization that underlies nerve and muscle function

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58
Q

principal cation in ECF

A

–sodium salts accounts for 90 -95% of osmolarity of ECF

–most significant solute in determining total body water and distribution of water among the fluid compartments

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59
Q

Na+-K+pump

A

–exchanges intracellular Na+ for extracellular K+

–generates body heat

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60
Q

Homeostasis

A

•adult needs about 0.5 g of sodium per day
–typical American diet contains 3 –7 g/day
•primary concern -excretion of excess dietary sodium

61
Q

sodium concentration coordinated by:

A

aldosterone
ADH
ANP
others:

62
Q

aldosterone

A

aldosterone-“salt retaining hormone”
•primary role in adjusting sodium excretion
•hyponatremia and hyperkalemia directly stimulate the adrenal cortex to secrete aldosterone
•hypertension stimulates its secretion by way of the renin-angiotensin-aldosterone mechanism
•aldosterone receptors in ascending limb of nephron loop, the distal convoluted tubule, and cortical part of collecting duct

63
Q

aldosterone, a steroid, binds to nuclear receptors

A

–activates transcription of a gene for the Na+ -K+ pumps
–in 10 –30 minutes enough Na+ -K+ pumps are inserted in the plasma membrane to make a noticeable effect
–tubules reabsorb more sodium and secrete more hydrogen and potassium
–water and chloride passively follow sodium

64
Q

primary effects of aldosterone are that

A

the urine contains less NaCl and more potassium and a lower pH

65
Q

ADH

A

modifies water excretion independently of sodium excretion
•high sodium concentration in the blood stimulate the posterior lobe of the pituitary to release ADH
•kidneys reabsorbs more water
•slows down any further increase in blood sodium concentration
•drop in sodium inhibits ADH release
•more water is excreted, raising the sodium level in the blood

66
Q

ANP

A

(atrial natriuretic peptide)
•inhibit sodium and water reabsorption, and the secretion of renin and ADH
•kidneys eliminate more sodium and water lowering blood pressure

67
Q

estrogen

A

mimics aldosterone and women retain water during pregnancy

68
Q

progesterone

A

reduces sodium reabsorption and has a diuretic effect

69
Q

sodium homeostasis is achieved by regulating salt intake

A

salt cravings in humans and other animals

70
Q

hypernatremia

A

plasma sodium concentration greater than 145 mEq/L
•from administration of IV saline
•water pretension, hypertension and edema

71
Q

hyponatremia

A

plasma sodium concentration less than 130 mEq/L
•person loses large volumes of sweat or urine, replacing it with drinking plain water
•result of excess body water, quickly corrected by excretion of excess water

72
Q

Potassium -Functions

A

most abundant cation of ICF
•greatest determinant of intracellular osmolarity and cell volume
•produces (with sodium) the resting membrane potentials and action potentials of nerve and muscle cells
•Na+-K+pump
–co-transport and thermogenesis
•essential cofactor for protein synthesis and other metabolic processes

73
Q

Homeostasis

A

•potassium homeostasis is closely linked to that of sodium
•90% of K+in glomerular filtrate is reabsorbed by the PCT
–rest excreted in urine
•DCT and cortical portion of collecting duct secrete K+in response to blood levels
•Aldosterone stimulates renal secretion of K+

74
Q

Potassium -Imbalances

A

most dangerous imbalances of electrolytes

75
Q

hyperkalemia

A

effects depend on whether the potassium concentration rises quickly or slowly
–greater than 5.5 mEq/L
–if concentration rises quickly, (crush injury) the sudden increase in extracellular K+makes nerve and muscle cells abnormally excitable
–slow onset, inactivates voltage-regulated Na+channels, nerve and muscle cells become less excitable
•can produce cardiac arrest

76
Q

hypokalemia

A

–less than 3.5 mEq/L
–rarely results from dietary deficiency
–from sweating, chronic vomiting or diarrhea
–nerve and muscle cells less excitable
•muscle weakness, loss of muscle tone, decreased reflexes, and arrhythmias from irregular electrical activity in the heart

77
Q

Chloride -Functions

A

•most abundant anions in ECF
–major contribution to ECF osmolarity
•required for the formation of stomach acid
–hydrochloric acid (HCl)
•chloride shift that accompanies CO2loading and unloading in RBCs
•major role in regulating body pH

78
Q

Chloride -Homeostasis

A

•strong attraction to Na+, K+and Ca2+, which chloride passively follows
•primary homeostasis achieved as an effect of Na+homeostasis
–as sodium is retained, chloride ions passively follow

79
Q

hyperchloremia

A

result of dietary excess or administration of IV saline

80
Q

hypochloremia

A

side effect of hyponatremia
–sometimes from hyperkalemia or acidosis
•primary effects:
–disturbances in acid-base balance

81
Q

Calcium -Functions

A
  • lends strength to the skeleton
  • activates sliding filament mechanism of muscle contraction
  • serves as a second messenger for some hormones and neurotransmitters
  • activates exocytosis of neurotransmitters and other cellular secretions
  • essential factor in blood clotting
82
Q

calcium homeostasis is chiefly regulated by

A

PTH, calcitriol(vitamin D), and calcitonin(in children)
–these hormones affect bone deposition and resorption
–intestinal absorption and urinary excretion

83
Q

calsequestrin

A

proteins that bind Ca2+ and keep it unreactive in Ca2+ storage cells

84
Q

hypercalcemia

A

greater than 5.8 mEq/L
–caused by alkalosis, hyperparathyroidism, hypothyroidism
–reduces membrane Na+permeability, inhibits depolarization of nerve and muscle cells
–concentrations greater than 12 mEq/L causes muscular weakness, depressed reflexes, cardiac arrhythmias

85
Q

hypocalcemia

A

less than 4.5 mEq/L
–caused by vitamin D deficiency, diarrhea, pregnancy, acidosis, lactation, hypoparathyroidism, hyperthyroidism
–increases membrane Na+permeability, causing nervous and muscular systems to be abnormally excitable
–very low levels result in tetanus, laryngospasm, death

86
Q

Phosphates -Functions

A

•relatively concentrated in ICF due to hydrolysis of ATP and other phosphate compounds
•inorganic phosphates (Pi) of the body fluids are an equilibrium mixture of phosphate (PO43-), monohydrogen phosphate (HPO42-), and dihydrogen phosphate (H2PO4-)
•components of:
–nucleic acids, phospholipids, ATP, GTP, cAMP, hydroxyapatite, and creatine phosphate
•activates many metabolic pathways by phosphorylating enzymes and substrates such as glucose
•buffers that help stabilize the pH of body fluids

87
Q

renal control

A

–normally phosphate is continually lost by glomerular filtration
–if plasma concentration drops, renal tubules reabsorb all filtered phosphate

88
Q

parathyroid hormone

A

–increases excretion of phosphate which increases concentration of free calcium in the ECF
–lowering the ECF concentration of phosphate minimizes the formation of calcium phosphate and helps support plasma calcium concentration
•imbalances not as critical
–body can tolerate broad variations in concentration of phosphate

89
Q

Acid-Base Balance

A

one of the most important aspects of homeostasis
–metabolism depends on enzymes, and enzymes are sensitive to pH
–slight deviation from the normal pH can shut down entire metabolic pathways
–slight deviation from normal pH can alter the structure and function of macromolecules
•7.35 to 7.45 is the normal pH range of blood and tissue fluid

90
Q

challenges to acid-base balance:

A

metabolism constantly produces acid

91
Q

lactic acids

A

from anaerobic fermentation

92
Q

phosphoric acid

A

from nucleic acid cataboli

93
Q

fatty acids and ketones

A

from fat catabolism

94
Q

carbonic acid

A

from carbon dioxide

95
Q

pH of a solution is determined solely by

A

its hydrogen ions (H+)

96
Q

acids

A

any chemical that releases H+ in solution

97
Q

strong acids

A

like hydrochloric acid (HCl) ionize freely
•gives up most of its H+
•markedly lower pH of a solution

98
Q

weak acids

A

like carbonic acid (H2CO3) ionize only slightly
•keeps most H+ chemically bound
•does not affect pH as much

99
Q

bases

A

any chemical that accepts H+

100
Q

strong bases

A

like the hydroxide ion (OH-), has a strong tendency to bind H+, markedly raising pH

101
Q

weak bases

A

such as the bicarbonate ion (HCO3-) bind less available H+ and has less effect on pH

102
Q

buffer

A

any mechanism that resists changes in pH

–convert strong acids or bases to weak ones

103
Q

physiological buffer

A

system that controls output of acids, bases, or CO2

104
Q

urinary system

A

buffers greatest quantity of acid or base

•takes several hours to days to exert its effect

105
Q

respiratory system

A

buffers within minutes

•cannot alter pH as much as the urinary system

106
Q

chemical buffer

A

a substance that binds H+ and removes it from solution as its concentration begins to rise, or releases H+ into solution as its concentration falls
–restore normal pH in fractions of a second
–function as mixtures called buffer systems composed of weak acids and weak bases

107
Q

three major chemical buffers

A

bicarbonate, phosphate, and protein systems

108
Q

bicarbonate buffer system

A

a solution of carbonic acid and bicarbonate ions.
•functions best in the lungs and kidneys to constantly remove CO2
–to lower pH, kidneys excrete HCO3-
–to raise pH, kidneys excrete H+and lungs excrete CO2

109
Q

functions best in the lungs and kidneys to

A

constantly remove CO2
–to lower pH, kidneys excrete HCO3-
–to raise pH, kidneys excrete H+and lungs excrete CO2

110
Q

phosphate buffer system

A

-a solution of HPO42-and H2PO4-

111
Q

H2PO4-HPO42-+ H+

A

–as in the bicarbonate system, reactions that proceed to the right liberating H+ and decreasing pH, and those to the left increase pH

112
Q

more important buffering the ICF and renal tubules

A

–where phosphates are more concentrated and function closer to their optimum pH of 6.8
•constant production of metabolic acids creates pH values from 4.5 to 7.4 in the ICF, avg. 7.0

113
Q

proteins

A

are more concentrated than bicarbonate or phosphate systems, especially in the ICF

114
Q

protein buffer system

A

accounts for about three-quarters of all chemical buffering in the body fluids
•protein buffering ability is due to certain side groups of their amino acid residues

115
Q

carboxyl (-COOH) side groups

A

which releases H+ when pH begins to rise

•others have amino (-NH2) side groups that bind H+ when pH gets too low

116
Q

Respiratory Control of pH

A

basis for the strong buffering capacity of the respiratory system
–the addition of CO2to the body fluids raises the H+ concentration and lowers pH
–the removal of CO2has the opposite effects
•neutralizes 2 to 3 times as much acid as chemical buffers

117
Q

CO2 is constantly produced by aerobic metabolism

A

–normally eliminated by the lungs at an equivalent rate
H2CO3HCO3-+ H+
•raises pH by binding H+
•increased CO2and decreased pH stimulate pulmonary ventilation, while an increased pH inhibits pulmonary ventilation

118
Q

Renal Control of pH

A
  • the kidneys can neutralize more acid or base than either the respiratory system or chemical buffers
  • renal tubules secrete H+ into the tubular fluid
119
Q

tubular secretion of H+

A

–continues only with a steep concentration gradient of H+ between tubule cells and tubular fluid
–if H+ concentration increased in tubular fluid, lowering pH to 4.5, secretion of H+ stops –limiting pH

120
Q

bicarbonate system

A

all bicarbonate ions in tubular fluid are consumed neutralizing H+
•so there is no HCO3-in the urine
•the more acid the kidneys secrete, less sodium is in the urine

121
Q

phosphate system

A

dibasic sodium phosphate is contained in glomerular filtrate
•reacts with some of the H+ replacing a Na+in the buffer which passes into the urine
•Na2HPO4+ H+ NaH2PO4 + Na+

122
Q

ammonia

A

(NH3) -from amino acid catabolism acts as a base to neutralize acid
•NH3+ H+ and Cl-NH4Cl (ammonium chloride –a weak acid)

123
Q

acid –base balance

A

depends on bicarbonate buffer system

124
Q

acidosis

A

pH below 7.35
–H+ diffuses into cells and drives out K+, elevating K+ concentration in ECF
•H+ buffered by protein in ICF, causes membrane hyperpolarization, nerve and muscle cells are hard to stimulate; CNS depression may lead to confusion, disorientation, coma, and possibly death

125
Q

alkalosis

A

pH above 7.45
–H+diffuses out of cells and K+ diffuses in, membranes depolarized, nerves overstimulated, muscles causing spasms, tetany, convulsions, respiratory paralysis
–a person cannot live for more than a few hours if the blood pH is below 7.0 or above 7.7

126
Q

acid-base imbalances fall into two categories:

A

respiratory and metabolic

127
Q

respiratory acidosis

A

–occurs when rate of alveolar ventilation fails to keep pace with the body‟s rate of CO2production
–carbon dioxide accumulates in the ECF and lowers its pH
–occurs in emphysema where there is a severe reduction of functional alveoli

128
Q

respiratory alkalosis

A

–results from hyperventilation

–CO2 eliminated faster than it is produced

129
Q

metabolic acidosis

A

–increased production of organic acids such as lactic acid in anaerobic fermentation, and ketone bodies seen in alcoholism, and diabetes mellitus
–ingestion of acidic drugs (aspirin)
–loss of base due to chronic diarrhea, laxative overuse

130
Q

metabolic alkalosis

A

–rare, but can result from:
–overuse of bicarbonates (antacids and IV bicarbonate solutions)
–loss of stomach acid (chronic vomiting)

131
Q

compensated acidosis or alkalosis

A

–either the kidneyscompensate for pH imbalances of respiratory origin, or
–the respiratory system compensates for pH imbalances of metabolic origin

132
Q

uncompensated acidosis or alkalosis

A

–a pH imbalance that the body cannot correct without clinical intervention

133
Q

respiratory compensation

A

changes in pulmonary ventilation to correct changes in pH of body fluids by expelling or retainingCO2

134
Q

hypercapnia

A

(excess CO2) -stimulates pulmonary ventilation eliminating CO2and allowing pH to rise

135
Q

hypocapnia

A

(deficiency of CO2) reduces ventilation and allows CO2 accumulate lowering pH

136
Q

renal compensation

A

an adjustment of pH by changing the rate of H+ secretion by the renal tubules
–slow, but better at restoring a fully normal pH

137
Q

in acidosis

A

urine pH may fall as low as 4.5 due to excess H+

•renal tubules increase rate of H+ secretion elevating pH

138
Q

in alkalosis

A

as high as 8.2 because of excess HCO3-

•renal tubules decrease rate of H+ secretion, and allows neutralization of bicarbonate, lowering pH

139
Q

renal compensation

speed

A

–kidneys cannot act quickly enough to compensate for short-term pH imbalances
–effective at compensating for pH imbalances that lasts for a few days or longer

140
Q

Fluid Replacement Therapy

A

one of the most significant problems in the treatment of seriously ill patients is the restoration and maintenance of proper fluid volume, composition, and distribution among fluid compartments

141
Q

fluids may be administered to:

A

–replenish total body water
–restore blood volume and pressure
–shift water from one fluid compartment to another
–restore and maintain electrolyte and acid-base balance

142
Q

drinking water is the simplest method

A

–does not replace electrolytes

–broths, juices, and sports drinks replace water, carbohydrates, and electrolytes

143
Q

patients who cannot take fluids by mouth

A

–enema –fluid absorbed through the colon
–parenteral routes –fluid administration other than digestive tract
•intravenous (I.V.) route is the most common
•subcutaneous (sub-Q) route
•intramuscular (I.M.) route
•other parenteral routes

144
Q

excessive blood loss

A

–normal saline (isotonic, 0.9% NaCl)
–raises blood volume while maintaining normal osmolarity
•takes 3 to 5 times the normal saline to rebuild normal blood volume because much of the saline escapes blood and enters interstitial fluid compartment
•can induce hypernatremia or hyperchloremia

145
Q

correct pH imbalances

A

–acidosis treated with Ringer‟s lactate

–alkalosis treated with potassium chloride

146
Q

plasma volume expanders

A

hypertonic solutions or colloids that are retained in the bloodstream and draw interstitial water into it by osmosis
–used to combat hypotonic hydration by drawing water out of swollen cells
–can draw several liters of water out of the intracellular compartment within a few minutes

147
Q

patients who cannot eat

A

–isotonic 5% dextrose (glucose) solution
–has protein sparing effect –fasting patients lose as much as 70 to 85 grams of protein per day
•I.V. glucose reduces this by half

148
Q

patients with renal insufficiency

A

–given slowly through I.V. drip

2 - Keiser A&P 2 (15 decks)

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