Anaesthetics- Use of IV fluids

Question 1

What percent of the body is total body water?

Answer 1

60%

Question 2

What is total body water (TBW) divided into?

Answer 2

• Intracellular fluid

* Extracellular fluid

Question 3

How much of TBW does intracellular fluid make up?

Answer 3

40% body weight (28L)

Question 4

How much of TBW does extracellular fluid make up?

Answer 4

20% body weight (14L)

Question 5

What is extracellular fluid divided into

Answer 5

• Interstitial fluid (11L)

* Plasma (3L)

Question 6

What is interstitial fluid?

Answer 6

Fluid in the spaces between cells

Question 7

What is transcellular fluid?

Answer 7

Fluid that fills the cavities in the body e.g. aqueous humour in the eye

Question 8

What is osmosis?

Answer 8

water moves from a dilute solution to a concentrated solution across a semi-permeable membrane

Question 9

What is the role of osmotic pressure?

Answer 9

Stop osmosis occurring, by applying pressure to the concentrated solution

Question 10

What does more particles in solution mean?

Answer 10

Higher the rate of osmosis therefore the higher the osmotic pressure

Question 11

What does hypertonicity cause?

Answer 11

Cellular dehydration

Question 12

What does hypotonicity cause?

Answer 12

Cell swelling

Question 13

What are the symptoms of tonicity changes?

Answer 13

Neurological

Question 14

What neurological symptoms does swelling of cells cause?

Answer 14

Raised icp
Compromised cbf
Herniation

Question 15

What neurological symptoms does Shrinkage of cells cause?

Answer 15

Ich venous sinuous thrombosis

Question 16

What are crystalloids?

Answer 16

Aqueous liquids that are soluble in water

Question 17

What are some examples of crystalloids?

Answer 17

• 5% dextrose
• 0.9% saline
• Hartmann’s solution

Question 18

What are the advantages of crystalloids?

Answer 18

• Cheap

* Non-allergenic

Question 19

What are some disadvantages of crystalloids?

Answer 19

• Ecf expansion

* (oedema/increased vascular pressure)

Question 20

What are colloids?

Answer 20

Aqueous liquids in insoluble in water

Question 21

What are some examples of colloids?

Answer 21

• Gelatins
• Starches
• Dextrans
• Albumin

Question 22

What are the disadvantages of colloids?

Answer 22

• Anaphylaxis
• Coagulopathy
• Renal failure
• rheology

Question 23

What are sensible losses?

Answer 23

Things you can measure

Question 24

What are examples of sensible losses?

Answer 24

Urine

Faeces

Question 25

What are insensible losses?

Answer 25

Things you cant measure

Question 26

What is an example of an insensible loss?

Answer 26

Sweat

Question 27

What is the maximum maintenance fluid you should give someone?

Answer 27

!00ml/hr

Question 28

Why should you not give someone more than 100ml/hr of maintenance fluid?

Answer 28

Risk of hyponatraemia

Question 29

What do you need to subtract when giving someone maintenance fluid?

Answer 29

Other oral intake

Question 30

How is IV maintenance fluid administered?

Answer 30

ml/hr via volumetric pump

Question 31

How should you alter maintenance fluid in the elderly?

Answer 31

Reduce it

Question 32

Which patients should be started on maintenance fluid immediately?

Answer 32

Patients fasting for ≥ 6hours

Question 33

Before giving replacement fluid, what do you need to add up?

Answer 33

Losses in the last 24hrs e.g. bleeding, D & V, drain output, fistulae and give this volume back Remember

Question 34

What is replacement fluid given in addition to?

Answer 34

Maintenance fluids

Question 35

What do you need to remember when giving replacement fluid?

Answer 35

* Urine output is a poor guide to fluid requirements | * Oliguria does not always require fluid therapy

Question 36

What replacement fluid could you give?

Answer 36

• PlasmaLyte 148

Question 37

What fluid would you give for upper GI losses?

Answer 37

0.9% NaCl with KCl

Question 38

How is replacement fluid administered?

Answer 38

Gravity giving set or volumetric pump

Question 39

What is resuscitation fluid used for?

Answer 39

For severe dehydration, sepsis or haemorrhage leading to hypovolaemia & hypotension

Question 40

How much resuscitation fluid should you administer?

Answer 40

Give fluid challenge of 250-500ml over 5-15 mins and reassess

Question 41

What fluid would you give as resuscitation fluid?

Answer 41

PlasmaLyte 148/colloid/blood