Lecture 4 Fluid Volume Balance

Question 1

how much of adult body weight is fluid?

Answer 1

60%

Question 2

how much of the body’s fluid is intracellular?

Answer 2

2/3

Question 3

how much of the body’s fluid is extracellular?

Answer 3

1/3

Question 4

what are the components of extracellular fluid?

Answer 4

intravascular
interstitial
transcellular

Question 5

what is osmosis?

Answer 5

• water goes towards higher solute concentration
• passive transport

Question 6

normal urine output

Answer 6

about 1mL/kg/hr
1-2 L per day

Question 7

what triggers RAAS and what does it do?

Answer 7

• triggered by low kidney perfusion
• retains sodium and salt in the body by reabsorption

Question 8

what do natriuretic peptide hormones do?

Answer 8

decrease water and sodium retention

Question 9

what is ADH?

Answer 9

• antidiuretic hormone, causes water reabsorption in the kidneys
• released in response to change in blood osmolality detected by the hypothalamus

Question 10

what indicates fluid status?

Answer 10

• body weight
• creatinine and BUN
• Urine specific gravity
• hemoglobin and hematocrit

Question 11

what does high creatinine and BUN mean?

Answer 11

waste products are not being filtered from the blood effectively, impaired kidney function

Question 12

what does urine specific gravity indicate?

Answer 12

low means more diluted urine
high means more concentrated urine

Question 13

isotonic

Answer 13

fluid that has same solute load as intracellular fluid

Question 14

hypotoic

Answer 14

lower solute load than intracellular fluid
causes cell swelling as water moves towards solutes

Question 15

hypertonic

Answer 15

higher solute load than intracellular fluid
causes cell shrinking as water moves towards solutes

Question 16

crystalloid IV fluid

Answer 16

• has electrolytes
• used to restore fluid volume

Question 17

what is isotonic IV fluid used for?

Answer 17

dehydration
maintaining fluid balance

Question 18

what is hypotonic IV fluid used for?

Answer 18

DKA
promotes fluid into cells

Question 19

what is hypertonic IV fluid used for?

Answer 19

treats cerebral edema
promotes fluid out of cells

Question 20

colloid IV fluid

Answer 20

large insoluble molecules
remains in vascular space for longer
used to treat hypovolemia

Question 21

what are common isotonic IV fluids?

Answer 21

0.9% NaCl (Normal Saline)
Lactated Ringer
D5W

Question 22

what are common hypotonic IV fluids?

Answer 22

0.45% NaCl (½ Normal Saline)
0.33% NaCl

Question 23

what are common hypertonic IV fluids?

Answer 23

3% or 5% NaCl
D5 with 0.45% or 0.9% NaCl

Question 24

what are common colloid IV fluids?

Answer 24

Albumin
Dextran
Plasma

Question 25

what can cause hpovolemia?

Answer 25

vomiting, diarrhea, NG suction
perspiration
hemorrhage
diabetes insipidus
diuretics
third spacing

Question 26

manifestations of hypovolemia

Answer 26

anxiety and confusion
tachycardia
tachypnea
hypotension
pallor
decreased urine output

Question 27

diagnostic findings for hypovolemia

Answer 27

increased urine specific gravity (more concentrated)
increased BUN and creatinine

increased hematocrit = decreased circulating volume
decreased hemoglobin and hematocrit = hemorrhage

Question 28

managing hypovolemia

Answer 28

promote oral fluid intake
Isotonic IV fluids initially
hypotonic IV fluids later - promote fluid into cells
blood products for hemorrhage

Question 29

monitoring response to hypovolemia treatment

Answer 29

strict I/Os
urine output
pulmonary status (pulmonary edema = fluid overload)
neuro status (cerebral edema from isotonic fluids)
vital signs

Question 30

what can cause hypervolemia?

Answer 30

retention of sodium and water
SIADH
heart failure
high salt diet

Question 31

diagnostic findings of hypervolemia

Answer 31

decreased HGB and HCT (blood more diluted by fluid)
decreased serum and urine osmolality
chest x-ray for pulmonary edema

Question 32

clinical manifestations of hypervolemia

Answer 32

headache and confusion
hypertension
tachycardia
JVD
pulmonary edema, dyspnea, crackles, tachypnea
general edema
decreased specific gravity of urine and increased UOP
acute weight gain

Question 33

managing hypervolemia

Answer 33

sodium restriction
fluid restriction
monitor daily weight
diuretics and dialysis
elevate HOB for pulmonary edema
lung sounds