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APEX > Unit 9 - Fluids & Electrolytes > Flashcards

Unit 9 - Fluids & Electrolytes Flashcards

1
Q

what is the plasma volume of a 70 kg male

A

3 L

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2
Q

total body water of 70 kg male

A

42 L

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3
Q

body water distribution in 70 kg male

A

60/40/20 (15/5)
water = 60 % TBW
ICF = 40% TBW (28 L)
ECF = 20% TBW (14 L)
interstitial fluid = 15% (11L)
plasma fluid = 5% (3L)

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4
Q

components of extracellular fluid

A

interstitial fluid (11L)
plasma (3 L)

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5
Q

major ions of ICF

A

K+, Mg2+, PO42-

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6
Q

major ions of ECF

A

Na+, Ca2+, Cl-, HCO3-

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7
Q

volume of ICF vs ECF

A

ICF = 40% of TBW or 28 L
ECF = 20% of TBW or 14 L

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8
Q

population differences in TBW

A
  • Neonates have higher TBW % by weight
  • Females, the obese, and the elderly have a lower TBW % by weight
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9
Q

what is plasma volume

A

non-cellular fraction of circulating blood volume

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10
Q

what determines net movement of fluid between intravascular & interstitial spaces

A

Starling forces & glycocalyx

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11
Q

what are starling forces

A

dictate passive exchange of water between capillaries and interstitial fluid

forces that move from capillary to interstitial space and vice versa

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12
Q

starling forces: Pc

A

Pc = capillary hydrostatic pressure (pushes fluid out of capillary)

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13
Q

Starling forces: π if

A

π if = interstitial oncotic pressure (pulls fluid out of capillary)

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14
Q

Starling forces: Pif

A

Pif = interstitial hydrostatic pressure (pushes fluid into capillary)

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15
Q

Starling forces: π c

A

π c = capillary oncotic pressure (pulls fluid into capillary)

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16
Q

how do fluids tend to be pulled back into the capillary

A

capillary oncotic pressure

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17
Q

how is fluid pushed out as it enters the capillary

A

capillary hydrostatic pressure

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18
Q

net filtration pressure =

A

(Pc - Pif) - (πc - πif)

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19
Q

NFP > 0 =
NFP < 0 =

A

> 0 = filtration (fluid exits capillary)
< 0 = reabsorption (fluid pulled into capillary)

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20
Q

Gatekeeper that determines what can pass from vessel into interstitial space

A

Glycocalyx

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21
Q

Conditions that impair glycalyx integrity

A

sepsis
ischemia
DM
major vascular surgery

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22
Q

function of glycocalyx

A
  • forms a protective layer on the interior wall of blood vessel
  • determines what can pass from vessel to interstitial space
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23
Q

blood volume =

A

sum of plasma volume and blood cell volume (60% plasma & 40% blood)

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24
Q

what is Hct

A

the fraction of blood volume occupied by erythrocytes

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25
Q

how is Hct increased

A

by increased # RBCs (polycythemia) or decreased plasma volume (hypovolemia)

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26
Q

how is Hct decreased

A

by decreased # RBCs (anemia) or increased plasma volume (hemodilution)

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27
Q

why are erythrocytes considered part of intracellular compartment

A

filled with fluid but considered part of intracellular compartment bc contained by a membrane

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28
Q

what is the interstitium

A

space between cells

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29
Q

what makes up nearly all of interstitial “fluid”

A

gel consisting of fluid & proteoglycan filaments

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30
Q

fluid movement in the interstitium is a function of:

A

diffusion

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31
Q

fluid scavenger that removes fluid, protein, bacteria, & debris that has entered the interstitium

A

Lymphatic System

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32
Q

how does the lymphatic system propel lymph

A

pumping mechanism

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33
Q

how does the lymphatic system affect pressure in interstitial space

A

Produces net negative pressure in interstitial space

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34
Q

what causes edema in regards to the lymphatic system

A

occurs when rate of interstitial fluid accumulation exceeds rate of removal by lymphatic system

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35
Q

how is lymph returned to venous circulation

A

via thoracic duct at juncture of IJ & subclavian

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36
Q

why is left IJ CVL insertion assoc. with greater risk of chylothorax

A

thoracic duct is larger on the left

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37
Q

how do most solutes get across semipermeable membranes separating the body’s compartments

A

carrier proteins transport these solutes from one side to another

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38
Q

what is osmosis

A

net movement of water across a semipermeable membrane (only water, not solute, can pass through membrane)

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39
Q

what drives direction of water movement via osmosis

A

difference in solute concentration on either side of membrane

Water tends to move from areas of lower solute to areas of higher solute concentration

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40
Q

what is diffusion

A

net movement of a substance from area of higher concentration to area of lower concentration across fully permeable membrane

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41
Q

pressure of a solution against a semipermeable membrane, prevents water from diffusing across that membrane

A

Osmotic pressure

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42
Q

what is osmotic pressure a function of

A

the number of osmotically active particles in a solution

NOT a function of molecular weights

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43
Q

number of osmoles per liter of solution

A

osmolarity

mOsm/L of total solution

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44
Q

number of osmoles per liter of solution

A

osmolarity

mOsm/L of total solution

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45
Q

number of osmoles per kg of solution

A

osmolarity

mOsm/kg of H2O

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46
Q

number of osmoles per kg of solution

A

osmolarity

mOsm/kg of H2O

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47
Q

number of osmotically active particles in a solution

A

osmole

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48
Q

normal plasma osmolarity

A

280-290 mOsm/L

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49
Q

Most important determinant of plasma osmolarity

A

Na+

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50
Q

how do hyperglycemia or uremia affect plasma osmolarity

A

can increase

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51
Q

helps us understand how different IV solutions impact volumes of ECF & ICF as well as plasma & cellular osmolarity

A

Dannow-Yannet Diagrams

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52
Q

what happens to cells in hypotonic solutions

A

water enters, cells swell

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53
Q

what happens to cells in hypertonic solutions

A

water exits, cells shrink

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54
Q

it is assumed that addition or loss of fluid occurs where?

A

in ECF

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55
Q

osmolarity of hypotonic solutions vs plasma

A

lower than plasma

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56
Q

how do hypotonic solutions affect ECF, ICF, and plasma osmolarity

A

↑ ECF & ICF volumes
↓ plasma osmolarity

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57
Q

why should a patient with increased ICP never receive a hypotonic solution

A

These fluids are akin to giving free water, which distributes throughout all body compartments

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58
Q

examples of hypotonic solutions

A

D5W
NaCl 0.45%

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59
Q

osmolarity of isotonic solutions vs plasma

A

Osmolarity approximates plasma (or cells)

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60
Q

how do isotonic solutions affect ECF, ICF, plasma volume, and plasma osmolarity

A

expand plasma volume & ECF (ICF and plasma osmolarity stay the same)

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60
Q

how do isotonic solutions affect ECF, ICF, plasma volume, and plasma osmolarity

A

expand plasma volume & ECF (ICF and plasma osmolarity stay the same)

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61
Q

how long do crystalloids tend to remain in intravascular space

A

~30 min

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62
Q

adverse effect of large amounts of NS

A

hyperchloremic metabolic acidosis

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63
Q

how does LR reduce risk of metabolic acidosis

A

Lactate in LR functions as a buffer
Lactate is converted to bicarb by liver & kidneys
Bicarb reduces risk of metabolic acidosis

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64
Q

what fluids can be used to dilute PRBcs

A

NS or Plasmaylte
(LR historically avoided but research shows that LR can be used safely when rapidly infusing PRBCs)

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65
Q

examples of isotonic solutions

A
  • NaCl 0.9%
  • Hespan 6%
  • Plasmalyte A
  • Albumin 5%
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66
Q

osmolarity of hypertonic solutions vs plasma

A

Osmolarity exceeds plasma (or cells)

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67
Q

how do hypertonic solutions affect intravascular volume, ECF, ICF, and plasma osmolarity

A
  • expand intravascular volume by pulling fluid from ICF into ECF
  • ECF & plasma osmolarity ↑
  • ↓ ICF
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68
Q

consequence of increasing serum Na+ too quickly

A

central pontine myelinolysis

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69
Q

examples of hypertonic solutions

A
  • 3% NS
  • D5LR
  • D5NS 0.9%
  • D5NS 0.45%
  • Dextran 10%
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70
Q

blood replacement volume with crystalloids

A

3:1

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71
Q

how long can crystalloids expand plasma volume

A

for 20-30 min

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72
Q

effects of dilution with crystalloids

A

dilutional coagulopathy
dilution of albumin = decreased capillary oncotic pressure

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73
Q

how long can colloids increase plasma volume

A

3-6 hours

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74
Q

effects of dextran 40

A

↓ blood viscosity
improves microcirculatory flow in vascular surgery

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75
Q

FDA black box warning on synthetic colloids

A

risk renal injury

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76
Q

coagulopathy with synthetic colloids

A

dextran > Hetastarch > Hextend

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77
Q

max volume of synthetic colloids

A

max 20 mL/kg

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78
Q

which colloid has the highest anaphylactic potential

A

dextran

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79
Q

synthetic colloid that does not have a problem with coagulopathy

A

Volvuven

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80
Q

only colloid that is derived from human blood products

A

albumin

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81
Q

Vd of albumin

A

approximates plasma volume

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82
Q

electrolyte imbalance possible with albumin

A

hypocalcemia (binds calcium)

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83
Q

normal serum potassium

A

3.5 - 5.5 mEq/L

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84
Q

plasma osmolarity calculation

A
85
Q

conditions that increase osmolarity

A

hypernatremia
hyperglycemia
uremia

86
Q

colloid that impairs ability to cross-match blood

A

dextran

87
Q

which expands ECF - crystalloids or colloids?

A

crystalloids only

88
Q

Most common electrolyte disorder in clinical practice

A

hypokalemia

89
Q

Most abundant intracellular cation

A

K+

90
Q

electrolyte that regulates RMP in nervous tissue, skeletal muscle, and cardiac muscle

A

K+

91
Q

responsible for maintaining intracellular distribution of K+

A

Na-K-ATPase

92
Q

Most important ion during repolarization of neural tissue & muscle cells

A

K+

93
Q

GI losses that can result in hypokalemia

A
  • V/D
  • NG suction
  • Zollinger-Ellison syndrome
  • jejunoileal bypass
  • kayexalate
94
Q

4 etiologies of hypokalemia

A
  1. diet (poor K+ intake)
  2. GI loss
  3. renal loss
  4. redistribution
95
Q

causes of renal loss of K+

A
  • diuretics
  • metabolic alkalosis
  • licorice (can cause pseudo-Conn’s syndrome)
96
Q

causes of hypokalemia from redistribution

(K+ shift intracellular)

A
  • insulin + D50
  • hyperventilation
  • bicarb
  • beta 2 agonists
  • hypokalemic periodic paralysis
97
Q

presentation of hypokalemia

A

skeletal muscle cramps
weakness
paralysis

98
Q

EKG findings with hypokalemia

A
  • long PR
  • long QT
  • flat T wave
  • U wave
99
Q

why is assessing total body K+ with a serum K+ often inaccurate

A

~98% of total body K+ is stored inside cells

100
Q

why is it important to evaluate cause of hypokalemia before treating

A

If due to intracellular redistribution, supplemental K+ could lead to lethal hyperkalemia when cause of redistribution resolves

101
Q

max rate of potassium infusion

A

PIV = 10 mEq/hr
CVL = 20 mEq/L

102
Q

5 etiologies of hyperkalemia

A
  1. increased intake
  2. impaired excretion
  3. redistribution
  4. cellular injury
  5. pseudohyperkalemia
103
Q

causes of impaired K+ excretion that can lead to hyperkalemia

A
  • acute oliguric renal failure
  • hypoaldosteronism
  • drugs that impair K+ excretion (NSAIDs, spironolactone, triamterene)
104
Q

drugs that impair K+ excretion

A

NSAIDs, spironolactone, triamterene

105
Q

causes of K+ redistribution that contribute to hyperkalemia

K+ shifts extracellularly

A
  • acidosis
  • succinylcholine
  • beta blockers
  • hyperkalemic periodic paralysis
106
Q

causes of cellular injury that contribute to hyperkalemia

A
  • tumor lysis
  • hemolysis
  • burns
  • crush injury
  • rhabdo
107
Q

EKG findings with hyperkalemia

A
  • 5.5-6.5 = peaked T waves
  • 6.5-7.5 = flat P wave, prolonged PR
  • 7.0-8.0 = prolonged QRS
  • > 8.5 = QRS - sine wave - V-fib
108
Q

serum K level associated with sine wave

A

8.5 or greater

109
Q

serum K+ assoc. with peaked T waves

A

5.5-6.5 mEq/L

110
Q

treatment of hyperkalemia

A
  • stabilize cardiac membrane with calcium
  • shift K intracellularly (insulin + D50, hyperventilation, bicarb, beta 2 agonist)
  • K+ elimination with K+ wasting diuretics, kayexelate, dialysis
111
Q

normal serum Na+

A

135-145 mEq/L

112
Q

Most abundant extracellular cation

A

Na+

113
Q

Primary determinant of serum osmolarity

A

Na+

114
Q

Plays important role in regulating ECF volume through osmotic forces

A

Na+

115
Q

when is Na+ most important

A

during depolarization of neural tissues and muscle cells

116
Q

how is Na+ homeostasis regulated

A
  • GFR
  • renin-angiotensin-aldosterone system
  • ANP/BNP
117
Q

consider delaying surgery if Na+ is <

A

130

118
Q

the serum Na+ concentration should be corrected no faster than:

A

2 mEq/L/hr

119
Q

consequence of treating hyponatremia too quickly

A
  • causes fluid to shift from ICF to ECF
  • can cause central pontine myelinolysis
120
Q

consequence of treating hypernatremia too quickly

A

causes fluid to shift from ECF to ICV
can cause cerebral edema

121
Q

serum Na+ that defines hyponatremia

A

< 135 mEq/L

122
Q

causes of hyponatremia related to decreased total body Na+ content

A
  • diuretics
  • salt-wasting disease
  • hypoaldosteronism
123
Q

causes of hyponatremia with normal total body Na+ content

A
  • SIADH
  • hypothyroid
  • water intoxication
  • periop stress
124
Q

causes of hyponatremia assoc with increased total body Na+ content

A

CHF
cirrhosis

125
Q

presentation of hyponatremia

A
  • 130-135 = no signs to mild signs
  • 125-129 = N/V, malaise
  • 115-124 = headache, lethargy, altered LOC
  • < 115 (rapid onset) = seizures, coma, cerebral edema, respiratory arrest
126
Q

s/s hyponatremia at 125-129 mEq/L

A

N/V
malaise

127
Q

s/s hyponatremia at 125-129 mEq/L

A

HA
lethargy
altered LOC

128
Q

Na+ level assoc with seizures and cerebral edema

A

< 115 mEq/L

129
Q

hyponatremia treatment

A

goal is to restore Na+ balance by manipulating serum osmolality and fluid balance with H2O restriction, IVF selection based on tonicity, and diuretics

130
Q

serum Na+ in hypernatremia

A

> 145

131
Q

etiologies of hypernatremia assoc with decreased total body Na+ content

A
  • osmotic diuresis
  • N/V
  • adrenal insufficiency
132
Q

causes of hypernatremia assoc with normal total body Na+ content

A

diabetes insipidus
renal failure
diuretics

133
Q

causes of hypernatremia assoc with increased total body Na+ content

A

hyperaldosteronism
↑ intake (3% saline)

134
Q

what determines presentation of hypernatremia

A

serum osmolality

serum Na+ concentration determines presentation with hyponatremia

135
Q

what determines presentation of hypernatremia

A

serum osmolality

serum Na+ concentration determines presentation with hyponatremia

136
Q

presentation of hypernatremia

A

depends on serum osmolality
* 350-375 = headache, agitation, confusion
* 376-400 = weakness, tremors, ataxia
* 401-430 = hyperreflexia, muscle twitching
* > 431 = seizures, coma, death

137
Q

normal total plasma calcium

A

8.5 - 10.5 mg/dL
4.5 - 5.5 mEq/L
or 2.12 - 2.62 mmol/dL

138
Q

normal ionized plasma calcium

A

4.65-5.28 mg/dL
2.2-2.6 mEq/L
or 1.16-1.32 mmol/dL

139
Q

Calcium:
____ % is ionized
____% is bound to albumin
____% is bound with an anion

A

50% is ionized
40% is bound to albumin
10% is bound with an anion

140
Q

Most abundant electrolyte in the body

A

calcium

141
Q

where is nearly all calcium stored

A

in bone

serves as a reservoir for maintaining plasma calcium level

142
Q

where is nearly all calcium stored

A

in bone

serves as a reservoir for maintaining plasma calcium level

143
Q

important functions of calcium

A
  • 2nd messenger systems
  • neurotransmitter release
  • muscular contraction
  • phase 2 of cardiac muscle cell AP
  • factor 4 in coagulation pathway
144
Q

Antagonizes effects of Mg2+ at NMJ

A

calcium

145
Q

how does acidosis affect ionized calcium

A

increases
(albumin binds H+ and displaces Ca2+ into plasma)

146
Q

how does alkalosis affect ionized calcium

A

decreases
(albumin binds Ca2+ and displaces H+ into the plasma)

147
Q

how does parathyroid hormone affect serum calcium

A

increases

148
Q

how does calcitonin affect serum calcium

A

decreases

149
Q

osteoclast activity with increased serum calcium level

A

inhibited

150
Q

what releases calcitonin in response to increased calcium level

A

thyroid

151
Q

parathyroid response to decreased calcium level

A

releases PTH

152
Q

how does the body respond to decreased calcium levels

A
  • parathyroid glands release PTH
  • osteoclasts release calcium from bone
  • calcium reabsorbed by kidneys
  • increased calcium absorption in small intestine (via vitamin D synthesis)
153
Q

etiologies of hypocalcemia

A
  • hypoparathyroidism
  • vitamin D deficiency
  • renal osteodystrophy
  • pancreatitis
  • sepsis
154
Q

presentation of hypocalcemia

A
  • skeletal muscle cramps
  • nerve irritability (paresthesia & tetany)
  • laryngospasm
  • AMS
  • seizures
  • Chvostek sign
  • Trousseau sign
155
Q

what phase of cardiac AP is calcium responsible for

A

phase 2 (plateau)

156
Q

which factor is calcium in the coagulation pathway

A

factor 4

157
Q

EKG findings of hypocalcemia

A

long QT

158
Q

serum calcium in hypocalcemia

A

< 8.5 mg/dL

159
Q

serum calcium in hypercalcemia

A

> 10.5 mg/dL

160
Q

etiologies of hypercalcemia

A

hyperparathyroidism, cancer, thyrotoxicosis, thiazide diuretics, immobilization

161
Q

presentation of hypercalcemia

A
  • nausea
  • abd pain
  • HTN
  • psychosis
  • AMS - seizures
162
Q

Chvostek sign

A

tapping on jaw of facial n./masseter muscle causes ipsilateral facial contraction

163
Q

trousseau sign

A

upper extremity BP cuff inflated above SBP for 3 minutes = decreased blood flow accentuates neuromuscular irritability = muscle spasms of hand and forearm

164
Q

electrolyte imbalance assoc with short QT

A

hypercalcemia

165
Q

hypercalcemia treatment

A

0.9% NaCl, Lasix

166
Q

normal total plasma magnesium level

A

1.7-2.4 mg/dL or 1.5-3 mEq/L

167
Q

where is Mg contained

A

Only 1% of total body Mg resides in ECF (0.3% in plasma)
The rest is contained intracellularly (mostly muscle and bone)

serum Mg may not correlate with total body Mg

168
Q

where is Mg contained

A

Only 1% of total body Mg resides in ECF (0.3% in plasma)
The rest is contained intracellularly (mostly muscle and bone)

serum Mg may not correlate with total body Mg

169
Q

antagonizes effects of calcium

A

Mg

170
Q

Required for DNA synthesis, essential cofactor in many enzymatic functions

A

magnesium

171
Q

where is most Mg reabsorbed

A

renal tubules

172
Q

what hormone raises serum calcium

A

parathyroid hormone

173
Q

what hormone decreases serum calcium

A

calcitonin

174
Q

serum Mg level assoc with loss of DTRs

A

7-12 mg/dL or 5.8-10 mEq/L

175
Q

dose of mag for preeclampsia

A

4g IV load over 10-15 minutes then 1 g/hr for 24 hours

176
Q

clinical uses of mag

A
  • Opioid-sparing techniques (NMDA receptor antagonism)
  • Acute bronchospasm
  • Cardiac rhythm disturbances: symptomatic PVCs or torsades de pointes
177
Q

neonatal risks of magnesium infusion

A

Mg crosses placenta
admin > 48h increases risk of neonatal respiratory depression, hypotension, & lethargy

178
Q

how does magnesium affect NMB

A

Hypermagnesemia can potentiate NMB with succs and nondepolarizers

179
Q

what should you assess in an OB patient receiving mag for preeclampsia

A

loss of DTRs

180
Q

etiologies of hypomagnesemia

A
  • poor intake
  • alcohol abuse
  • diuretics
  • critical illness
  • common with hypokalemia
181
Q

serum Mg that defines hypomagnesemia

A

< 1.8 mg/dL or < 1.5 mEq/L

182
Q

presentation of Mg < 1.2 mg/dL (or < 1 mEq/L)

A
  • tetany
  • sz
  • dysrhythmias
183
Q

s/s Mg 1.2-1.8 mg/dL or 1-1.5 mEq/L

A
  • neuromuscular irritability
  • ↓ K+
  • ↓ Ca2+
184
Q

EKG findings with hypomagnesemia

A

not significant unless very low (long QT)

185
Q

treatment of hypomagnesemia

A

mag sulfate supplementation

186
Q

serum Mg in hypermagnesemia

A

> 2.5 mg/dL or > 2.1 mEq/L

187
Q

etiologies of hypermagnesemia

A
  • excessive admin
  • renal failure
  • adrenal insufficiency
188
Q

s/s hypermagnesemia:
5-7 mg/dL

A

decreased DTRs
lethargy/drowsiness
flushing
N/V

189
Q

s/s hypermagnesemia:
7-12 mg/dL

A
  • loss of DTRs
  • ↓ BP
  • EKG changes
  • somnolent
190
Q

s/s hypermagnesemia:
> 12 mg/dL

A
  • resp depression - apnea
  • complete heart block
  • cardiac arrest
  • coma
  • paralysis
191
Q

magnesium levels assoc with dysrhythmias

A

< 1.2 mg/dL or > 7 mg/dL

192
Q

treatment of hypermagnesemia

A

CaCl or CaGluconate

193
Q

4-2-1 rule for calculating fluid maintenance

A
  • 4 mL/kg/hr for first 10 kg body weight
  • 2 mL/kg/hr for second 10 kg body weight
  • 1 mL/kg/hr for each subsequent kg of body weight

For an adult, can use body weight in kg + 40 mL

194
Q

4-2-1 rule for calculating fluid maintenance

A
  • 4 mL/kg/hr for first 10 kg body weight
  • 2 mL/kg/hr for second 10 kg body weight
  • 1 mL/kg/hr for each subsequent kg of body weight

For an adult, can use body weight in kg + 40 mL

195
Q

calculating fluid deficit

A

fasting hours x calculated hourly IVF rate

196
Q

third space replacement

A
  • Very minimal surgical trauma (ex. orofacial surgery): replace 1-2 mL/kg/hr
  • Minimal surgical trauma (ex. inguinal hernia): replace 2-4 mL/kg/hr
  • Moderate surgical trauma (ex. major nonabdominal surgery): replace 4-6 mL/kg/hr
  • Severe surgical trauma (ex. major abdominal surgery): replace 6-8 mL/kg/hr

existence of third space is controversial

197
Q

why is UOP an unreliable measure of fluid status

A

ADH reduces the kidney’s ability to eliminate fluid

198
Q

fundamental objective of goal directed fluid therapy

A

optimizing O2 delivery

199
Q

how does inadequate or excessive fluid affect O2 delivery

A
  • Inadequate circulating volume reduces CO and O2 delivery
  • Excessive circulating volume promotes microvascular congestion (also impairs O2 delivery)
200
Q

which area of the starling curve best correlates with preload dependence

A

slope (ascending limb)

201
Q

key principle of goal directed fluid therapy

A

admin. of small quantities of fluid (~200-250 mL) to determine the difference between preload dependence and preload interdependence

202
Q

what does plateau of Starling curve suggest

A
  • Suggests an optimal balance between circulating volume and myocardial performance
  • Additional fluid would not be expected to improve hemodynamics or O2 delivery and might cause harm by pushing the patient further right on the curve
203
Q

risks of overshooting the Starling curve

A

CHF
pulmonary edema

204
Q

ERAS was originally designed for what types of surgeries

A

colon

205
Q

3 most important determinants of plasma osmolarity

A
  1. Na+
  2. BUN
  3. glucose
206
Q

consequence of correcting hyponatremia too quickly

A

osmotic demyelination syndrome

more common when hyponatremia persisted > 48 hrs

207
Q

consequence of correcting hyponatremia too quickly

A

osmotic demyelination syndrome

more common when hyponatremia persisted > 48 hrs

208
Q

sodium concentration of solutions containing 0.9% NaCl

includes 5% albumin, NS, D5NS

A

154 mEq/L

209
Q

sodium concentration of 5% albumin

A

154 mEq/L

210
Q

which IVF is most physiologic

A

plasmalyte (Na+ 140)

211
Q

Na+ concentration of LR-containing solutions

A

130 mEq/L

includes LR and D5LR

APEX (54 decks)

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