IV fluids

Question 1

Why is it important to learn about IV fluids?

Answer 1

up to 20% patients receiving IV fluids experiencing complications or morbidity

Question 2

Diffusion

Answer 2

movement of solute from high to low concentration

membrane must be solute permeable

Question 3

osmosis

Answer 3

movement of water from high to low concentration

membrane must be solute impermeable

Question 4

osmolarity

Answer 4

all solute concentrations

solute concentration per unit volume of solvent

Question 5

osmolality

Answer 5

solute concentration per unit mass of solvent

Question 6

tonicity

Answer 6

osmotic pressure gradient

solute unable to cross membrane

Question 7

Fluid physiology - 70kg male

Answer 7

42L
2/3 ICF = 28L
1/3 ICF = 14L - 20% (3l) intravascular

Question 8

osmolality in ECF and ICF

Answer 8

285-290mOsm/kg - the same

Question 9

water requirements a day

Answer 9

25-30ml/kg

Question 10

glucose requirement a day

Answer 10

50-100g

Question 11

potassium requirement a day

Answer 11

1mmol/kg

Question 12

sodium requirement a day

Answer 12

1mmol/kg

Question 13

water content of fat

Answer 13

10% water

Question 14

water content of muscle

Answer 14

75%

Question 15

4 main questions with fluid balance

Answer 15

1. patients volume status
2. need IV fluids?
3. how much fluid?
4. what kind of fluid?

Question 16

assessing patients volume status

Answer 16

age, gender, muscle mass, insensible loss, physiology
ABCD
ventilation, SOB (pulmonary oedema)
circulation - raised JVP
mucous membranes, reduced skin turgor, sweat

Question 17

Hypovolaemia characteristics

Answer 17

nauseous - thirsty - flat veins - cool peripheries - low bp - low HR - no sweat - concentrated oliguria

Question 18

Hypovolaemic patient needs?

Answer 18

resuscitation fluids - low bp
rehydration fluids
plug the leak

Question 19

Euvolaemia characteristics

Answer 19

feels well, not thirsty, normal bp and HR, veins well fixed, mild sweat

Question 20

Euvolaemic patient needs?

Answer 20

no fluids unless low bp or electrolyte deplete

Question 21

hypervolaemia characteristics

Answer 21

SOB, veins distended, sweaty, warm and oedematous extremities, high bp and HR, dilute urine

Question 22

hypervolaemic patient needs?

Answer 22

no more fluids
diuretics
haemofiltration if anuric

Question 23

particularly tricky situations

Answer 23

low oncotic pressure - low albumin (oedema)

heart failure

Question 24

How to work out water deficit

Answer 24

catheters - drains - input charts - stool and stoma - sputum pots - vomit bowls

Question 25

Insensible losses volume and areas

Answer 25

400-800ml

sepsis (sweat), ventilation, burns, bleeding, open wounds

Question 26

3 main types of fluids given and what membranes they cross

Answer 26

dextrose - all membranes, crystalloids - stays in ECF, plasma expanders

Question 27

D5W good for

Answer 27

hypernatraemia

Question 28

D5W not good for

Answer 28

resuscitation, low albumin

Question 29

Crystalloids good for

Answer 29

AKI, acute dehydration, resuscitation, sepsis

Question 30

crystalloids not good for

Answer 30

hypernatraemia

Question 31

colloids good for

Answer 31

liver patients, bleeding, intra-op

blood, TPN

Question 32

Resuscitation fluids

Answer 32

IV fluids urgently to restore circulation with hypovolaemia

Question 33

routine maintenance fluids

Answer 33

IV fluids if not taken orally or enterally

Question 34

Replacement fluids

Answer 34

IV additional to maintenance or correct existing deficit or ongoing abnormal external losses eg diarrhoea

Question 35

redistribution fluids

Answer 35

abnormal internal fluid redistribution or fluid handling eg sepsis, liver or renal patients, tissue oedema

Question 36

5th R

Answer 36

reassessment